1

BAITING FOR ACOUSHI ANT CONTROL

Baiting is the recommended method of control for acoushi ants. It exploits the insects feeding behavior. Like the vegetation which is cut and carried back to the nests, bait picked up by the ants is taken back to the nest to be used as substrate for the fungus which is the ants only food (Figure 3). Bait consists of a toxicant or poison and a carrier which is usually Fig. 3- Bait being picked a material that the insects find attractive. The material must be up by Ants attractive (Figure 4) since this determines the degree of acceptance of the bait by the insects.

A C O U S H I A N T

Fig. 4 - Acoushi Ant Bait

The Acoushi ant bait is recommended to control the pineapple ants. This bait must be crushed in the bag to break the pellets into smaller pieces. Before the crushed bait is placed in the field, the area should be weeded so the nests present are exposed. During the rainy weather, the bait should be placed in a glass jar or aluminum foil packets to prevent wetting. Nests which are away from the plant should be disturbed and the bait placed close to, but not in the nests. Ant nests which are on the plant should be disturbed to agitate the ants and the crushed bait placed at the base of the plant. The ants will then take the bait back to their nests where control will occur.

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PRECAUTIONS

i.

Do not store bait for more than three months after the production date (date is stamped on packet). ii. Use all the bait once the packet has been opened. iii. Store bait in a cool, dry place. iv. Store bait out of the reach of children.

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Introduction The Avocado ( Persea Americana Miller) is an evergreen tree of the family Lauraceae with seedling plants reaching 67ft (20m) in height with small large, single seeded fruits having yellow to yellowish green butter-like flesh. Mature fruit vary in colour and may be green, yellow, purple or red. Cultivation There is always a great demand for Avocado plants and the NARI Plant Nurseries are finding it difficult to keep up with this demand. Consequently, the availability of plants at the Plant Nurseries cannot be guaranteed at any time. Although there are seedling trees around, Avocado plants are commonly grafted as this reduces the time taken for bearing, combines the best characteristics of varieties and improves resistance/tolerance to diseases. Fruits are collected from healthy, vigorous, mature trees and deseeded; the seeds are washed, dried and sown individually in black plastic bags, broad side down and covered with not more than 1 inch (2.5cm) of soil. Grafting is done when plants have attained a height of about 1.5ft (0.5m). Wedge grafting is the type commonly used. The scions for grafting are collected from healthy, vigorous, mature trees having desirable traits e.g. fruit size, flavour and shape. The graft is wrapped securely and covered with clear plastic until it catches. This is seen if graft remains green and buds start to burst into leaf after 2-3 weeks. During this entire process the plants should be protected from severe sunlight and receive adequate water until transplanting in field. Avocado plants are ready for planting out in the field approximately 6-9 months after grafting. Site Selection Avocado can be grown on a variety of soils but it does not thrive on the coastland. Nevertheless, wherever the avocado is planted there is need for good drainage since its shallow root system makes it sensitive to poor drainage and water logging. Selection of Varieties There are numerous varieties of Avocados but they all have either of two flowering patterns: A or B. The A type flowers are those which show receptive female parts in the morning and receptive male parts in the afternoon of the following day. The B type flowers show receptive female parts in the afternoon and receptive male parts in the morning of the following day. With this mechanism the female parts of the A type flowers are thus receptive to pollen from the B type flowers in the mornings, whilst the female parts of the B type flowers are receptive to pollen form the A type flowers in the afternoon. Avocado is not commonly self-pollinated, therefore it is important to encourage crosspollination by having A and B type trees in the orchard or backyard.

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Sandy Soil - the above is to b e used at the higher rate as well as 9:27:9 +FTE at the rate of 1/41b (112 g) to 1/21b (225 g) per plant once per year. PEST MANAGEMENT There are no major pest problems in Avocado. The most serious are Mites (Figure 1) and Scale Insects and these could be controlled by the use of Danitol (Fenpropathrin) or Rogor (Dimethoate) at 0. 02 pts per gallon (10 mls/4L). It should be noted that the occurrence of any unusual pest or disease must be reported to the Crop Protection Section at NARI for investigation.

A A V V O O C C A A D D O O

Mite Mite damage Fig 1. Mite and damage caused DISEASE MANAGEMENT Three main fungal diseases affect avocado: Avocado root rot (Phytophthora spp.) Anthracnose (Colletotrichum gloeosporiodes) Scab (Elsinoe perseae) 1. Avocado Root Rot (Phythophthora spp.)

Fig 2. Symptoms of Avocado root rot.

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3. Scab (Elsinoe perseae)

Fig 4. Scab on fruit and leaf

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Fig 5. Scab on fruit Symptoms Raised cream coloured to pale brown / orange warts are seen on the fruit and leaf surface (Figures 4 and 5). Control Pruning to increase air-flow within the canopy of the tree may be done to reduce the incidence of this disease. Harvest Maturity Indices The flowering period in avocados ranges from about 4 to 14 weeks, depending on cultivar and environmental conditions. Therefore, fruits from the same tree will vary in maturity dates. Determination of the correct harvest time is important because it affects the fruit quality and market life. It is important to pick the fruit when mature, as immature fruits will shrivel and not ripen properly. Determining the appropriate harvest maturity may be difficult and experience is important. Fruit of some avocado cultivars, particularly of the West Indian race, fall from the tree when physiologically mature and must be picked prior to fruit drop. In cultivars from the Guatemalan race and its hybrids, the fruits remain attached to the tree for as long as three or four months after physiological maturity has been reached. Avocados generally do not ripen while they are attached to the tree. Fruits are still hard when mature and ripen only after being picked.

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Since all cultivars are susceptible, anthracnose control depends on good orchard sanitation and control of other diseases (especially Cercospora spot) and avoidance of cuts and bruises to the fruit in handling. Fruits showing any sign of anthracnose should not be packed in cartons with healthy fruit. Dipping the fruit in a 500 ppm solution of thiabendazole may also reduce the incidence of anthracnose. Cooling the fruit to 13C (55.5F) and maintaining that temperature during marketing will minimize anthracnose development. Harvesting fruits in an immature condition can contribute to anthracnose appearance since the fungus may infect immature fruit and remain dormant, with subsequent invasion of the flesh through small cracks made during ripening or postharvest handling. Stem End Rot Stem end rot is caused by two different fungal organisms, Botryodiplodia theobromae and Dothiorella gregaria. Symptoms appears as an initial dark brown to black discolouration beginning at the stem end and advancing toward the blossom end, finally covering the entire fruit (Figure 7). Decay develops rapidly as the fruit softens. Stem end rot is usually only a problem with immature harvested fruit and can be prevented by harvesting fruit at the proper stage of maturity. Control measures used for anthracnose will also help minimize stem end rot. Fusarium Rot Fusarium rot is caused by several species of Fusarium. Infection usually takes place via the stem end or through injuries in the skin (Figure 8). This fungal disease accelerates the rate of softening and ripening. Recommended control measures are similar to those used for combating anthracnose.Fig 7. Stem end rot of avocado fruit.

A A V V O O C C A A D D O O

Rhizopus Rot Rhizopus rot is caused by the fungus Rhizopus stolonifer. It is characterized by rapid decay of ripe avocados with the formation Fig 8. Fusarium rot of of avocado. a coarse white mold on the fruit surface. Liquid may leak from the fruit and the odour is unpleasant. Infection is associated with wounds and can be significantly reduced by careful harvest and postharvest handling to minimize mechanical injuries. Chilling Injury Guyanese avocados are susceptible to chilling injury when kept at temperatures below 10C (50F). External symptoms of chilling injury include browning or blackening of the skin, pitting, and sunken lesions. Internal symptoms include browning around the vascular bundles and/or a general grayish-brown discolouration of the flesh (Figure11). Chilling injured fruit fail to ripen normally, develop off-flavours, and are highly susceptible to pathogen attack. The amount of chilling injury damage depends on the storage temperature, duration of exposure to chilling temperatures, Fig 9. Internal flesh darkening cultivar, production area, and maturity-ripeness stage.of chilling injured avocados.

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INTRODUCTION Bora (Vigna sesquipedalis) also known as long bean or yard long bean is a popular crop and is grown throughout Guyana. The dark green pods can be used raw as in salads or cooked in stews, etc. The plant can be grown in a variety of soils but does best on fertile, well drained, loose soils with high organic matter content. CULTIVATION VARIETIES There are a number of bora varieties cultivated in Guyana. These include the Yars Long, Long Green, Cabbage Bora, ect. The typical characteristics of some of the common varieties cultivated in Guyana are shown below: Bora type Yard Long Indeterminate local variety. Pods 120cm long. Plants bushy; pods medium in diameter. Long Green Indeterminate local variety. Pods 76cm long. Coarse in diameter. Cabbage Bora Indeterminate. Pods are about 30cm, pods fine in diameter. String Bora Plant is not bushy. Pods are very fine and long. Fat Bora Intermediate pods (50cm long); very fat in diameter. Thread Bora Medium sized plant. Pods about 40-50cm long; pods fine. Land Preparation Clay soils should be ploughed and harrowed to produce a good tilth. To enhance drainage on these soils, ridges should be made about 60cm apart. Sandy soils should be raked and rows made 60cm apart. Planting A seed rate of 10-15 kg/ha should be used. Seeds should be inoculated with the Rhizobium bacteria before planting, especially if bora is produced on the soil for the first time. Inoculation helps the plant to utilize atmospheric nitrogen from the air and reduces the amount of nitrogenous fertilizers necessary. To apply inoculum, first dampen the seeds with water, mix thoroughly with the inoculum using approximately 14 grams inoculum to 1kg of seeds. On clay soils when ridges are used plant about two seeds for each hole 30cm apart and 2.5cm, deep. On sandy soils sow two seeds per hole 30cm apart and 60cm, between rows. Staking Plants should be staked to enable them to make maximum use of the sunlight. There is no hard and fast method for staking and the method most suited to the farmer could be adopted. Fertilizer Recommendations It is desirable to have the soil tested before applying fertilizers. A soil test will inform you about the nutrient status of your soil and will help you to use fertilizers wisely. However, where soil test data are not available the following can be used as a guide. (a) Clay soil Limestone broadcast approximately 3t/ha evenly over the soil surface and work it into the soil to a depth of 15cm. This should be repeated every 3 years. Alternatively, apply about 100 gram into the soil at each planting hole and mix thoroughly. All the limestone should be applied at least 4 weeks before planting. About 10-14 days after planting apply

B O R A

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Proper land preparation serves to control weeds, diseases, and soil insects, and also helps in the destruction of large soil clods, which act as hiding places for cricket. Integrated Pest Management

Chemical Control Any approved soil insecticide at the recommended rate may be applied, such as Basudin 60% E.C (Diazinon) or Vydate L 40%E.C at the rate of 10 mls to 4500 mls water, to seed beds and cultivated areas of cropping. Cut worm Agrotis spp. (Lepidoptera: Noctuidae) These are the caterpillars of various species of moth. They have a greasy appearance, are grey to brown in colour with faint seedlings at or slightly above the soil surface. Evidence of cutworm presence will be greenish-black excreta pellets below seedling. Most of its lifecycle is spent below the soil which goes through a period of approximately. 21-28 days. CONTROL Cultural Control Good field sanitation- rid the field of weeds and plant residues from previous crops. The areas where vegetables are grown should receive full sunlight; kept clean of weeds and all crop residues should be removed and burnt. Proper land preparation serves to control weeds, diseases, Fig 2. Larva & adult and soil insects, and also helps in the destruction of large soil clods,of cutwormas hiding which acts places for cutworms. Integrated Pest Management

B O R A

Chemical Control Any approved soil insecticide at the recommended rate may be applied, such as Basudin 60% E.C (Diazinon) or Vydate L 40%E.C at the rate of 10 mls to 4500 mls water, to seed beds and cultivated areas of cropping. Aphids Aphis cracsivora (Homoptera: Aphididae) This pest attacks all vegetables. They are commonly known as plant lice or nit and are small, yellow, green or black pinhead-size insects (Figure 3). They are soft bodied, slow moving and multiply rapidly within a short time span. These insects attack plants at all stages of growth and are usually found in dense clusters on the under surface of the young leaves and also on young tender stems and growing point. They suck plant sap and make the plant weak; some also act as vectors of plant diseases. Seedlings are weakened and killed when the infestation is high, and growth of older infested plants is retarded. Infested leaves curl, shrivel and may turn brown and die. Aphids secrete a sweet substance known as honey dew while they feed. This substance attracts ants and serves as a substrate for sooty mould (black fungus) thus impairing photosynthesis. Lifecycle ranges between 21-28 days. 17 17

Chemical Control Several new generation insecticides are now available for the effective control of white flies. Targeting both nymphs and adults with soap based products, should be applied very early in the morning or late in the evening. Other chemicals which may be used include Admire, Pegasus and or Basudin/ Vydate L at 10 mls to 4500 mls water. Mites Tetranychus spp. (Acarina: Tetranychidae) Mites are arachnids and are not insects. (Adults have four pairs of legs and two pairs of eyes.) They are extremely tiny and appear as dust- like particles on the underside of leaves (Figure 5). Their colour ranges from red, translucent fawn to green. Eggs are laid on the underside of leaves and hatch beneath a web; which is spun by the adults. Both immature and mature stages suck plant sap resulting in leaves becoming yellow and eventually turning reddish. Fruits may also be affected especially by the rust mite. CONTROL Cultural Control Good field sanitation- rid the field of weeds and Fig 5. Egg and adult of mites plant residues from previous crops. Integrated Pest Management Chemical Control During severe infestations chemical control may become necessary. Any miticide may be used for their control such as Abamectin, Newmectin, and Vertimec at 5mls to 4500mls water. Thrips Frankiniella sp. (Thysanoptera: Thripidae) Thrips are yellow, tiny, elongated insects about 1mm in length and can be found on the upper and lower surfaces of leaves (Figure 6). Infestations are more severe in the dry season. Both young and adult suck the sap from leaves and cause them to loose their colour. If attack occurs early the young leaves becomes distorted. Older tissues become blotched and appear silvery or leathery in affected areas thus hindering photosynthesis. Flowers and fruits are also affected thus yields are reduced. Infected fruits are discolored, distorted and hardened. Thrips are also vectors or major virus disease. Lifecycle maybe completed in about 14-21 days.

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Fig 6. Thrips and damage caused 19 19

CONTROL Cultural Control Field sanitation is an important tool in the management of this pest. The removal and destruction of residue from previous crops will greatly reduce adult populations thus lowering Fig 8. Damage due to the potential infestation of the next crop. The removal of alternate hosts through weed management leaf miner also helps in lowering adult population. Integrated Pest Management

Chemical Control

B O R A

Several chemicals are now available for the management of this pest; among them are Trigard, Admire, Pilarking, Vertimec, Abamectin and Newmectin. Use the lower to middle range of the dosage recommended on the labels.

Bean beetle Cerotoma arcuata Diabrotica sp. Coleoptera: Chrysomelidae The bean beetle (Figure 9) may affect the plant throughout its life; however, its attack immediately after germination is most important since this can cause the death of plants or retardation of growth. The insect eats leaves causing shot holes; additionally it is a vector of the cowpea mosaic virus. CONTROL Cultural Control Chemical Control Pod Borer Maruca testulalis Lepidoptera :Pyralidae Egg the eggs are laid individually or in small batches on flowers or flower buds, sometimes partly covered with scales, and also on terminal shoots of young plants. The egg period lasts an average of 3 days (Figure 10). Several first-instar larvae may be found together among flowers, thereafter they disperse singly, moving from one flower to another so that each larva damages 4-6 flowers. Young larvae may feed on any part of the flowers or foliage, but later-instar larvae are more common in the pods. The pupal stage lasts an average of 6-7 days. 21 21 Any contact insecticide with some residual properties can give effective control of this pest e.g. Malathion, Karate, Fastac or Sevin. Fig 9. Bean beetle Field sanitation is an important tool in the management of this pest. The removal and destruction of residue from previous crops will greatly reduce adult population thus lowering the potential infestation of the next crop. The removal of alternate hosts through weed management also helps in lowering adult population. Integrated Pest Management

Chemical Control Use appropriate bactericides-Banrot, Mankocide. CERCOSPORA LEAF SPOT (Cercospora spp.) Symptoms Lower foliage becomes marked by irregular tan spots (Figure 12). Severe infection causes defoliation and plant stunting. Infection is most severe during periods of extended rainfall and high humidity. Cultural Control Use an integrated crop ma nagement approach. No resistance exists among varieties. Chemical Control Fungicide sprays should begin at first sign of disease.

B O R AFig 12. Symptoms of cercospora leaf spot

TARGET SPOT (Corynespora cassiicola) Symptoms Survives on leaves and pods Conidia produced on infested leaves cause primary infections (Figure 13). Conidial dispersal can be restricted within the crop during the growing season. This disease is somewhat slower than other common leaf spots and certainly much slower than the epidemics of rusts that are commonly encountered; this may have important implications for disease control. Cultural Control Fig 13. symptoms of target spot Use an integrated crop management approach. Chemical Control Copper based fungicide sprays should begin at first sign of disease. ROOT ROT (Rhizoctonia solani) Symptoms Bora seed may rot in soil or the young seedling may become stunted (Figure 14). A reddish-brown canker is formed on the stem. Cankers may completely girdle the stem or may only partially girdle it, causing severe stunting. Cultural Control Field sanitation; Bora should be planted in the dry season; Crop rotation bora should follow forage crop; and/ or Use an integrated crop management approach Chemical Control Banrot, Manzeb or Dithane M 45 are recommended.

Fig 13. symptoms of target spot

Fig 14. Symptoms of root rot

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SEEDLING DAMPING-OFF (Pythium sp.) This pathogen affects a wide range of plants in the seedling stage. Symptoms: Pythium sp. occurs in most cultivated soils. Infected seedlings appear water soaked at the soil level (Figure 18). This disease is favoured by high humidity and overcrowding. Results of Infection: Seedlings topple over, often when the leaves are still green. Fig 18. Symptoms of seedling Cultural Control damping-off Use an integrated crop management approach. The use of good quality seed and plants. Sowing or planting under optimum conditions is essential to reduce infection. Avoid overcrowding and over watering. Use seeds coated with Captan or Thiram. Soil sterilization also reduces infection. Chemical Control Spray with approved fungicides Dithane M45 or Captan. ROOT KNOT DISEASE (Meloidogyne javanica) Symptoms: The nematodes stimulate the formation of root galls, which interfere with the plants water supply, resulting in stunted and chlorotic growth, poor fruit setting and yellowing (Figure 19). The females lay several hundred eggs which are released into the soil. They enter the plant tissues, such as the root tips and stimulate the formation of galls. Cultural Control Use an integrated crop management approach. Resistant cultivars can limit the spread of the infection. Crop rotation is sometimes successful. Insects can be treated with hot water to kill larvae. Bury the residues of infected plants, to reduce the level of infection. Chemical Control Spray with approved nematicide-Nemacur FUSARIUM WILT (Fusarium oxysporium) This pathogen infects many crops. Acid soils and high temperature encourages this disease to spread. This is a soil-borne disease, often invading plants through roots or wound. The vascular system is infected, toxins are produced and the xylem turns brown (Figure 20). Seedlings may rot, leaves turn yellow and wilt. Plants may eventually die.

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Cultural Control Losses can be reduced by growing resistant varieties and following an approved aphid control program. Use resistant varieties.

Chemical Control Pesticides can be used to control the vectors of the various viruses.

Harvest Maturity Indices Bora is harvested at an immature stage, prior to full development of the seeds and pod. The initial harvest maturity can be estimated by counting the number of weeks after planting. Bora requires about 7 weeks from seeding until the start of harvest, depending on cultivar and environmental conditions. The harvest period typically continues over a period of about 6 to 8 weeks. Pod length and pod diameter are the two principal indices of harvest maturity. Pod diameter is more closely related to edible quality than length. Bora is typically harvested when the pods have reached a minimum length of 38 cm (15 inches). However, some markets prefer longer pods of up to 76 cm (30 inches). Pod length is significantly influenced by vigor of the plant and cultivar. Highly vigorous plants may produce pods of 90 cm (35 inches) in length. Highest quality pods are straight, crisp, and uniform in colour (Figure 22). The most popular cultivars have a green colour, although specialty markets may prefer cultivars which produce a reddish-coloured pod (Figure 23).Figure 22. Long, straight dark green bora ready for harvest. Figure 23. Purple coloured bora pods for specialty markets.

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Pod diameter enlarges with maturity and bora should be harvested when the pods have reached about 1 cm (0.4 inches) in diameter. At this diameter the immature seeds will be slightly protruding or bulging outward (Figure 24). Bora should be harvested before the seeds fill out the pods. Pod diameter should not exceed 1.25 cm (0.5 inches). Overmature pods are tough and unsuitable for eating. Harvest Methods Bora should be harvested by pinching the stem with the thumbnail pressed against the index finger. A short section of the stem should remain attached to the pod. If done carefully, twisting of the pod off the plant can be done provided the stem remains attached to the pod. Pickers should be careful not to tear or pull the pods off the plant. The pod should never be severed below the stem, as this creates an open wound in the pod which would be a likely site for decay establishment. Rough handling of the pods during harvest should be avoided as this will result in tissue damage and subsequent decay. In addition, harvested pods should never be packed tightly into the harvest container or allowed to remain in the sun for extended periods. Do not put damaged, diseased, or culled pods in the same harvest container as the marketable pods. 27 27

Generally, bora should not be washed because of the likelihood of spreading decay organisms. However, the Barbados export market requires a postharvest wash treatment for phytosanitary reasons (Figure 27). In this case, bora should be submerged in clean water adjusted to a pH of 6.5 and sanitized with 150 ppm hypochlorous acid. Household bleach is the most convenient source of hypochlorous acid and is widely available in a 5.25% solution. Following the washing treatment, the bora pods should be air dried on a clean, flat surface before sorting and grading (Figure 28).Figure 27. Cleaning of bora in properly sanitized wash water for the Barbados market. Figure 28. Fan used to speed up air drying of bora prior to grading and packing.

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Sorting/Grading There are no established grade standards for bora, but the pods should be sorted according to length, maturity, and external appearance. The length and thickness of the harvested bora pods is often quite variable. Uniform length and diameter of the bora pods in each bundle and carton is critical for market acceptance. Pod colour should be bright and typical of the cultivar. Each pod should be free of blemishes. Pods displaying rusty brown spots or other blemishes indicate disease, injury, or the possibility of deterioration and should be discarded. The pods should be well-formed and straight, uniform in colour with a fresh appearance, and tender but firm (Figure 29). They should snap easily when bent. Freshness is indicated by a distinct, audible snap when the pod is broken. Buyers prefer bora with no bulge or only a slight bulge, which indicates the pods are tender with immature seeds. Overmature bora with bulging pods are tough and fibrous. On the other hand, too immature pods are highly susceptible to wilting. Packing Bora is typically wrapped in bunches for marketing (Figure 30). Exporters prefer to purchase bora in larger bunches of 350 individual pods, while domestic markets prefer smaller bunches.

Figure 29. High quality pods are long and straight with a uniform green colour.

Figure 30. Bora wrapped in small bunches (foreground) for domestic marketing.

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Relative Humidity Harvested bora is highly susceptible to water loss and wilting. Pod shriveling and loss of crispness will soon occur if the postharvest relative humidity (RH) is low. About 5% weight loss is needed before shriveling and limpiness are observed. After 10% to 12% weight loss, the bora is no longer marketable. The rate of water loss from immature pods is higher than from more mature pods. In order to minimize wilting and quality loss, bora should be held at 95% RH. This may be obtained by the use of a supplemental humidifier or water vaporizer in the cooling and storage area. Packaging materials that allow for the establishment of a high RH microenvironment should also be used. Principal Postharvest Diseases Bora is a highly perishable vegetable crop subject to various fungal and bacterial decays. The principal postharvest fungal diseases of bora include cottony leak, rhizopus rot, gray mould, watery soft rot, and anthracnose. The principal postharvest bacterial disease is soft rot. Cottony Leak Cottony leak, caused by the soil-borne fungus Pythium, is a common postharvest decay of bora. Infection begins in the field and the decay progresses after harvest. The incidence of cottony leak is higher during the rainy season. The first symptoms of cottony leak are dark lesions of irregular shape, which enlarge rapidly at ambient temperatures. Under humid conditions, a white cottony mould may cover the pod and liquid may leak from the rotting tissue (Figure 33). Mould from infected pods will spread to adjacent healthy pods, forming nests of decay in packed cartons. In order to minimize cottonly leak, bora should always be harvested when dry and handled with care to avoid wounding of the pod surface. In addition, the pods should be cooled to 5C (41F) immediately after harvest.Figure 33. White mould associated with cottony leak.

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Rhizopus Rot Rhizopus rot, caused by the fungus Rhizopus, is another common postharvest disease of bora. Injury predisposes the pods to infection, which occurs under warm, moist conditions. Initially, small watersoaked spots form on the pod surface. The decayed tissue becomes soft and watery, with considerable leakage of fluid. Grayish-white masses of mould develop over the infected area (Figure 34). In contrast to cottony leak, Rhizopus rot is characterized by the formation of coarse strands of white mould and round black spore heads. A distinctive sour odour may accompany the decay. Nests of mould and decaying pods form within a carton of packed bora. The main ways to control Rhizopus rot are to harvest when the pods are completely dry, avoid injury to the pods during harvest and handling, and cool the pods to 5C (41F) immediately after harvest. Moisture condensation on the pod surface should also be avoided during transport to market.

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Bacterial Soft Rot Bacterial soft rot, caused by Erwinia carotovora, is the main postharvest bacterial disease of bora. The bacteria is a secondary decay organism and attacks tissue weakened by injury, sunscald, chilling injury, or fungal attack. Soft rot rapidly develops in warm, moist storage environments. Pods become soft, slimy, and foul smelling (Figure 38). Control of this disease is obtained by careful harvesting and handling practices to prevent wounding of the tissue, avoiding postharvest fungal growth, and maintenance of the pods at 5C during transport and distribution to market.Figure 38. Slimy rot symptoms of bacterial soft rot.

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Halo Blight Halo blight, caused by Pseudomonas syringae, is another bacterial disease that may infect bora. The disease is most commonly observed on pods harvested during the rainy season. Symptoms first appear as tiny, water-soaked pinpricks on the surface. These gradually enlarge and appear as small greasy spots scattered on the pod (Figure 39). The spots eventually darken, appear sunken, and sometimes a whitish ooze is emitted from the center. Development of halo blight is rapid under ambient temperatures. Control of this disease is obtained by planting disease-free seed, avoiding harvest when the pods are wet, and holding the bora at 5C(41F). Figure 39. Severe infection of halo Postharvest Disorders Chilling Injury Storage of bora at temperatures less than 4C (42F) will result in chilling injury (CI) to the pod. Symptoms appear as surface pitting, brown streaks, a general dullness of the pod colour, and increased susceptibility to decay. Injury may be induced within several days, although cultivars differ in sensitivity. Furthermore, symptoms may not become apparent until the pods have been returned to ambient temperature for a few days. The presence of free moisture on the surface of the pod aggravates the effects of CI.blight.

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INTRODUCTION Boulanger (Solanum melongena) belongs to family Solanacea. It is one of the leading vegetable crops grown in Guyana and is used mainly as a cooked vegetable. VARIETIES The most popular cultivars in Guyana are long fruited, purple skinned, and are egg- shaped to elongate, (i.e. Black Beauty, Suriname Long). Pink, white, and green skinned types are also produced with miniature size fruit. All the varieties are open pollinated. A brief description of the common varieties grow in Guyana is shown below: Pink & White May be 2-3 types: fruit are long or short and fat. Pink & white in colour. Colouation varies from more pink than white to more white than pink. Long Purple May be 2 types: fruit is long and smooth, and segmented. Deep purple in colour. Black Beauty Three types: short with large diameter located at (type 1), (type 2) or 1/3 (types 3) the fruit length. Segmented at the base. Black Boulanger Similar to Black Beauty; no segmented base; short shelf-life Corentyne Purple Fruit long, segmented, skin rough; light purple in colour. Short shelf-life. CULTIVATION The seed is initially sown in seed trays or seedbeds, and then transplanted four weeks after germination. It is grown on a wide range of soil types, but preferably suited to clay soil rich in organic matter. It grows well within a pH range of 5.5 6.5. If the pH is lower then appropriate quantities of limestone should be applied four six weeks before transplanting (based on soil test recommendations). Transplanting is best carried out in the afternoon or anytime during a cool day so as to resist transplanting shock. The recommended spacing should be 90cm between rows and 60cm along rows (a plant population of 18,500 plants/hectare). After transplanting, irrigation should be done once daily. Appropriate irrigation systems should be then practiced. FERTILIZER USE A soil test should be done to determine the fertilizer requirements. In the absence of a soil test, the following recommendation is provided as a guide: Urea 272 kg/ha - 30% at transplanting (4.4g/plant) - 40% at flowering (5.9g/plant) - 30% at Fruit set (4.4g/plant) TSP MoP 108 kg/ha 136kg/ha All at transplanting (5.8g/plant)

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50% at transplanting (3.7g/plant) 50% at flowering (3.7g/plant) If organic manure is to applied as well, then the synthetic fertilizer rate should be lowered appropriately. 35 35

Cultural control: The areas where vegetables are grown should receive full sunlight, kept clean of weeds and all crop residues should be removed and burnt. Proper land preparation serves to control weeds, diseases, and soil insects, and also helps in the destruction of large soil clods, which act as hiding places for crickets. Chemical control: Any approved soil insecticide at the recommended rate may be applied, such as Basudin 60% E.C (Diazinon) or Vydate L 40%E.C at the rate of 10 mls to 4500 mls water to seed beds and cultivated areas of cropping.

2. Cut wormAgrotis spp. (Lepidoptera: Noctuidae) These are the caterpillars of various species of moth (Figure 2 & 3). They have a greasy appearance, are grey to brown in colour with faint lightercolored strips, and when fully grown are usually the colour of the soil in which they live. They can be found on the soil surface, beneath leaves and under large soil clods. Cutworms are surface feeders, and cut seedlings at or slightly above the soil surface. Evidence of cutworm presence will be greenish-black excreta pellets below the seedling. Most of its lifecycle is spent below the soil which lasts for a period of approximately 21-28 days. CONTROL Good field sanitation- rid the field of weeds and plant residues from previous crops. Cultural control: The areas where vegetables are grown should receive full sunlight; kept clean of weeds and all crop residues should be removed and burnt. Proper land preparation serves to control weeds, diseases, and soil insects, and also helps in the destruction of large soil clods, which act as hiding places for cutworms.

Fig 2. Cutworm in the early stages

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Fig 3. Adult cutworm

Chemical control: Any approved soil insecticide at the recommended rate may be applied, such as Basudin 60% E.C (Diazinon) or Vydate L 40%E.C at the rate of 10 mls to 4500 mls water to seed beds and cultivated areas of cropping.

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Eggs are laid in the soil near the roots of the plant. These hatch in 5-7 days and the slender white larvae feed on the roots for 14-21 days. Because of the small sizes, feeding does not interfere with plant growth and development. Adult beetles emerge approximately 28 days from the soil. During a severe adult infestation, leaves appear scorched. Such an infestation can result in substantial yield loss and plants may be killed in one to three days. Control: Good field sanitation- rid the field of weeds and plant residues from previous crops. Chemical control: When the infestation level is high chemical control is recommended. Insecticides such as Decis, Fastac or Karate (6 mls to 4500 mls water), Sevin (85% W.P at 10gms to 4500 mls water), Sumithion (50% E.C. at 5mls to 4500 mls water) are recommended.

5. Lace wing bugsCroythaica cyathicollis: (Hemiptera: Tingidae) Lace wing bugs are usually found in clusters on the under surface of leaves. Adults are about 1.5 -3 mm in length and have characteristic lacy patterned wings (Figure 6). Their sucking action results in leaf mottling. The mottled areas eventually become necrotic and this leads to premature abscission of leaves. The life cycle lasts for approximately 28-35 days. Control: Good field sanitation- rid the field of weeds and plant residues from previous crops.

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Fig 6. Lace wing bugs

Chemical control: Decis, Karate or Fastac at 6 mls to 4500 mls water Sevin or Padan at 5gms to 4500 water are recommended.

6. Pin wormKeiferia lycopersicella: (Lepidoptera: Gelechiidae) Pin worm is a common pest of Boulanger. It is the caterpillar of a moth, which feeds on leaf surfaces, making blotch mines in the leaves. Leaves are often rolled or folded, such that the larvae are protected from natural enemies. In severe infestations, leaf surfaces are destroyed causing leaves to wither and die. The larvae can also mine in stems and feed on Fig 7. Pinworm flowers, thus reducing yields. The larvae can also invade fruits and destroy them. The adult is a grey moth about 5mm long (Figure 7). The larvae, which at first are light-orange in colour become purplish-black at maturity and are about 5mm long. Eggs are laid primarily on the underside of leaves and hatch within 5-7 days. Pupation may occur in the soil, or in folded leaves. The lifecycle may be completed in 21-35 days.

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Control: Good field sanitation- rid the field of weeds and plant residues from previous crops.

Chemical control: During severe infestations chemical control may become necessary. Any miticide may be used for their control such as Abamectin, Newmectinor, Vertimec at 5mls to 4500mls water.

9. ThripsFrankiniella sp. (Thysanoptera: Thripidae) Thrips are yellow, tiny, elongated insects (Figure 10) about 1mm in length and can be found on the upper and lower surfaces of leaves. Infestations are more severe in the dry season. Both young and adult suck the sap from leaves and cause them to loose their colour. If attack occurs early the young leaves becomes distorted (Figure 11). Older tissues become blotched and appear silvery or leathery in affected areas thus hindering photosynthesis. Flowers and fruits are also affected, thus yields are reduced. Infected fruits are discoloured, distorted and hardened. Thrips are also vectors for major viral disease. The lifecycle may be completed in about 14-21 days.

Control: Good field sanitation- rid the field of weeds and residue of all previous crops.

Fig 10. Adult thrips

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Cultural control: Crop rotation- cultivation of crops (vegetables) which is not a host to the pest. e.g. Cabbage can followed by Boulanger. Overhead irrigation will help in reducing populations of thrips during the dry season. An integrated approach is recommended for the management of thrips.

Fig 11. Damage caused by thrips

Chemical control: Among the insecticides which may be used are Regent (Fipronil), Admire, Abamectin and Vydate L at 5 mls to 4500 mls water, to both surfaces of leaves for effective control N.B. Spray should be directed to both surfaces of leaves for effective control.

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Major Diseases of Boulanger (Solanum melongena L.) and Management Strategies 1. FRUIT ROTFruit rot is a fungal diseases caused by Phomopsis vexans Symptoms: This fungus forms pycnidia on stems and diseased fruit. The fungus also causes blight in mature plants and damping off of seedlings. The fruits may show small, dull sunken spots, which enlarge in size and cover a major portion of the fruit, and rotting ensues (Figure 15). In severe cases, the entire fruit may be damaged.

Control: The use of resistant varieties or chemical treatment with Benomyl is recommended for control of fruit rot.

Fig 15. Fruit rot in boulanger

2. BACTERIAL WILTThe causal agent is (Ralstonia solanacearum) This is a serious bacterial disease which affects solanaceous crops. Warm wet weather encourages the spreadof the disease. Symptoms: Pathogen exists in the soil and infects plants through the roots, invading the vascular system. The xylem is discoloured and becomes only partially effective. Results of Infection: Affected plants are usually stunted and susceptible to water stress. They finally wilt and die (Figure 16). Control: Rotate with non-susceptible crops, or use resistant cultivars. Grafting onto resistant rootstocks is practiced with tomato and boulanger. Fig 16. Symptoms of bacterial wilt

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Control: Resistant cultivars can limit the spread of the infection. Crop rotation is sometimes successful. Insects can be treated with hot water to kill the larvae. The residues of some plants, when buried in the soil, reduce the level of infection.

6. FUSARIUM WILTThe causal agent is (Fusarium oxysporium) This pathogen infects many crops. Acid soils and high temperatures encourage the spread the disease. Symptoms: This is a soil-borne disease, often invading plants through roots or wounds. The vascular system is infected, toxins are produced and the xylem turns brown (Figure 20). Results of Infection: Seedlings may rot and the leaves turn yellow and wilt. Plants may eventually die. Fig 20. Typical symptoms of fusarium wilt

Control: The control measure recommended are crop rotation, planting in disease free soil and the use of clean planting material. Burning of crop debris and the planting of resistant cultivars are also recommended

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7. PHYTOPHTHORA FRUIT ROTThe causal agent is (Phytophthora parasitica) This is a wide spread disease of Solanaceous plants. Symptoms: Dark circular lesions, with a watery appearance, develop on the fruits and stems. In wet weather, white mycelial growth develops on the crop debris. Results of Infection: Mature fruits turn brown and often rot within a few days. Control: Provide adequate spacing to reduce humidity within the crop. Remove and burn infected fruits and crop debris and spray with copper fungicides.

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Weeds of Boulanger (Solanum melongena L.) and their Management StrategiesCompetition with weeds causes significant reductions in Boulanger crop yields and quality. Weed - crop competition is effected by both, the critical period of weed interference, that is the period where it is essential to maintain a weed-free environment to prevent yield losses and secondly the weed thresholds, that is the weed density that causes unacceptable yield loss. Weed management in Boulanger in Guyana currently relies on only a few herbicides along with cultural practices, such as hand weeding and hoeing. Since it is uneconomical to hire labour for hand weeding and hoeing, herbicides are widely used. Harvest Maturity Indices Boulanger is harvested at a range of maturity stages, depending on market demand. Days from flowering can be used as a harvest maturity index, and range from about 10 days for small fruit to about 4 weeks for large fruit. Large fruit should weigh in the range of 0.34 kg to 0.5 kg (0.75 lb to 1 lb). Elongated type fruit should weigh 136 g to 226 g (0.3 lb to 0.5 lb). Optimum maturity is best judged by size, and the fruits should be relatively heavy in relation to their size. The ideal harvest size for Black Beauty is when the fruit reaches a diameter of 10 cm to 15 cm (4 in to 6 in) and a minimum length of 10 cm, while Surinam Long should be harvested when fruit length is at least 5 cm (2 in) in diameter and 23 cm (9 in) in length. Boulanger fruit is typically harvested at an immature stage, before the seeds begin to enlarge and harden. As the fruit matures, the flesh softens and becomes spongy. Boulanger becomes pithy and bitter when they are over-mature. Boulanger is over-mature if an indentation remains after pressing the tissue with the thumb. Over-mature fruit have a dull external appearance and the seeds turn brown. Fruit should be harvested when it is firm, fully formed, glistening, and the seeds and pulp are white. Purple-skinned fruit should be harvested when it reaches a dark, glossy, uniform, purpleblack colour. The fruit should be firm and non-wrinkled. Frequent pickings will result in higher yields. Harvest Method Fruits of marketable size should be harvested by cutting the tough stem of the fruit with a sharp clippers (Figure 22) rather than tearing it off the plant. The calyx or cap should be fresh and green in appearance and left attached to the fruit. The length of the stem should be cut short ( 2.5 cm or 1 in) to avoid puncturing of adjacent fruit. Cotton gloves should be worn during harvest to protect the pickers hands against injury from spines on the calyx and to minimize fruit damage. Deformed, sunburned, insect damaged, and diseased fruit should be removed from the plant and discarded. Harvest frequency is typically once per week.

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Waxing A thin coating of wax can be applied to boulanger to enhance the appearance and shine of the skin surface and to reduce postharvest shriveling (Figure 24). Waxing also reduces chafing and abrasion injury from the rubbing of adjacent fruit during transport. Application of a liquid carnauba-based food grade wax is recommended. It can be applied by manually rubbing it over the surface of the skin or by using a soft bristled brush. Packing Boulanger should be handled and packed carefully to avoid damage to the skin. Strong, well-ventilated fiberboard cartons should be used for export, with a minimum carton bursting strength of 275 lb/in. Package weight is typically 9 to 11 kg (20 to 23 lb), containing 18 to 24 fruit per carton. The fruit should be laid flat and oriented horizontally along the same plane inside the carton (Figure 25). This will prevent the stem from puncturing adjacent fruit.

Fig 24. Waxing the surface adds shine to the ruit.

Fig 25. Packing the fruit parallel in the same container will avoid fruit puncture.

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Boulanger can also be individually wrapped in paper, and carefully packed into containers to prevent stems from puncturing adjacent fruits. Boulanger is packed in different sized containers, depending on the export market destination. North American markets generally require boulanger to be packed in 1 1/9-bushel (16 kg or 35 lb) or 5/9bushel cartons (8 kg or 18 lb). A 1 1/9-bushel carton will typically contain 18, 24, or 30-count sized boulanger. Temperature Management Boulanger does not have a long storage life and should be marketed immediately after harvest. For maximum postharvest life, boulanger should be held at 10C (50F). At this temperature, boulanger will typically have a 10 day market life. Boulanger stored for too long or at too high a temperature will have a dull and shriveled skin along with a dry and brown calyx (Figure 26). Once the colour of the skin begins to dull, the seeds darken and the flesh becomes spongy and bitter.Fig 26. Brown calyx and shriveled skin of eggplant stored for 2 weeks.

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Insect Pests of Cabbage in Guyana1. Cricket Gryllotalpa spp. (Orthoptera: Gryllotalpidae) Acheta spp. (Orthoptera: Gryllidae) Cricket attacks seedlings of all vegetables. Fully grown crickets are brown in colour and are about 2.5 3.5 cm long (Figure 1). The various species of these insects usually live either in the soil, bushes and under decaying crop residues and vegetation. Mole crickets, which have heavily sclerotised front legs that are adapted for digging, are usually common in sandy soils. All crickets are nocturnal, feeding at night and secluded by day, under the soil. They feed at or slightly below the soil surface, and can cause considerable damage before being discovered. Seedlings may be denuded of leaves or cut below the soil surface without any trace of insects on them. Fig 1. Adult cricket Crickets spend their entire life cycle below the soil, which may go through a period of approximately 28 -35 days. They are termed soil insects. Control

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Good field sanitation- rid the field of weeds and plant residues from previous crops.

Cultural control: The areas where vegetables are grown should receive full sunlight, kept clean of weeds and all crop residues should be removed and burnt. Proper land preparation serves to control weeds, diseases, and soil insects, and also helps in the destruction of large soil clods, which act as hiding places for cricket. Chemical control: Any approved soil insecticide at the recommended rate may be applied, such as Basudin 60% E.C (Diazinon) or Vydate L 40%E.C at the rate of 10 mls to 4500 mls water, to seed beds and cultivated areas of cropping.

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Control

Good field sanitation- rid the field of weeds and plant residues from previous crops.

Biological control: The natural predator lady bird beetles frequently feed on aphids. When aphid population is low and lady bird beetles are present, there is no need for chemical control. Chemical control: This may be applied when the population is high. A contact or stomach insecticide may be used such as: Fastac, Decis or Karate at 6mls to 4500mls water, Sevin 85% W.P. (Carbaryl) at 6g to 4500 mls water or Malathion 57% E.C. at 15 mls to 4500 mls water. . N.B. Sprays should be directed to underside/surfaces of leaves when Sevin or Malathion is used. Do not harvest crops until 7 -10 days after application of chemical. In the case of Fastac, Decis or Karate, crops can be harvested within 3-5 days after chemical application. 4. White flies Bemisia tabaci (Homoptera: Aleyrodidae) These insects are in fact bugs. The adults are white, moth-like insects that fly upwards from the plant when disturbed. They are about 2 mm in length and their wings are covered with a white waxy powder (Figure 3). The pinhead size nymphs are oval and flattened, and are attached to the leaf surface until maturity. All stages of this pest can be found on the underside of leaves. Nymphs and adults feed by sucking plant sap, resulting in leaves becoming mottled, yellow and brown before dying. Feeding whiteflies excrete honey dew on the leaf surface which encourages the growth of sooty mould thus hampering photosynthesis. Ants are also attracted to the Fig 3. Nymph and adult honey dew. This pest is also a vector of viral diseases. whitefly The life cycle may be completed in about 28-35 days. Control Cultural practices: Do not plant a new crop next to one which is mature: The common practice of having mature crops adjacent to newly planted ones makes management of the pest very difficult since the cycle of the pest is never broken. An integrated control strategy is necessary for the effective management of this pest. Chemical control: Several new generation insecticides are now available for the effective control of white flies. Targeting both nymphs and adults with soap based products which should be applied very early in the morning or late in the evening is effective. Other chemicals which may be used include Admire, Pegasus and or Basudin/ Vydate L at 10 mls to 4500 mls water.

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6. Budworm Hellula phidilealis (Lepidoptera:Pyralidae) Budworms are caterpillars (Figure 5), which feed on the young innermost leaves and then bore into the midribs or axils of leaves or into the growing point . The burrowing of the caterpillars into the growing point may result in retarded growth and frequently in the death of the plants. Cabbages often fail to produce heads when the growing point is damaged. Instead lateral buds may develop. The several heads formed from the lateral buds of a plant are very small and unmarketable. Fig 5. Budworm Control Crop rotation Crop rotation usually helps in breaking the cycle of a pests development through the absence of host plants. The repeated planting of any one crop type ensures the availability of host material for development of the pest. Chemical control Decis 2.5% EC-1.5 g/litre water, Ambush 5% EC-1 ml/litre water, Karate 2.5% EC-1.5 ml/litre water, Neem water extract, Dipel-3.5 g/litre water,Agree-3.5 g/litre water, Regent (Fipronil)10ml/18 litre water are recommended for the control of the cabbage budworm. 7. Cabbage Butterfly Pieres phileta (Lepidoptera: Pieridae)

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Larva

Fig 6. Larva and adult cabbage butterfly

Adult

8. Armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae)

Larva Fig 7. Larva and adult armyworm

Adult

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2. Fusarium Yellow (Fusarium oxysporum) The first indication of the disease is the yellowish-green color of the foliage. Plants appear wilted and stunted (Figure 10). The fungus can live in the soil for a number of years without a host plant. It infects plants through wounds caused by transplanting or insects. The disease is checked by very cold or very hot soil temperature. Control Use resistant varieties Crop rotation will avoid crop loss.

Chemical control Use any of the following as directed on the label: Carbendazine, Cuprasan, Captan, Kocide, and Mankocide. 3. Alternaria Leaf Spot (Alternaria brassicae) The first symptom is a minute dark spot on seedling stems and on the leaves. These spots enlarge and are marked with concentric rings, giving a bulls eye appearance (Figure 11). Spores are disseminated by wind or water. Control Use resistant varieties Hot water treatment, as recommended for black rot, will rid the Fig 11. Symptoms of seed of this organism. alternaria leaf spot Fungicide application will prevent the fungus from developing in the field.

Fig 10. Cabbage infected with fusarium wilt.

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Chemical control Use any of the following as directed on the label: Carbendazine, Cuprasan, Captan, Kocide, and Mankocide. 4. Soft Rot (Erwinia carotovora) Soft rot occurs most commonly when fields become water saturated. Stems become decayed and have a foul odor (Figure 12). During storage and transit, a slimy decay with a foul odor develops. The disease begins in areas that have been bruised, particularly during periods of high temperature and humidity prevail. Control Crop rotation Plant on raised beds in well drained soil to prevent field infections. Fig 12. Symptoms of soft rot

Chemical control Use any of the following as directed on the label: Mankocide, Rizolex and Banrot.

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Size is the principal indicator of harvest maturity and this is largely based on market demand. Pak choi should have wellformed upright petioles tightly adhering together (Figure 16). Pak choi should always be picked when leaves are fresh and crisp and before the outer leaves turn yellow. Harvest Methods Cabbage is harvested by hand by bending the head (or stalk in the case of pak choi) to one side and cutting it with a sharp knife or small machete. The cutting instruments should be Fig 16. Ideal harvest stage sharpened frequently to reduce harvesting effort and lessen picker fatigue. for pak choi. The head should not be removed by snapping or twisting it, as this practice damages the head and results in jagged appearing stems which extend too far out from the base of the head. Broken stems are also more susceptible to decay. The stalk should be cut flat and as close to the head as possible, yet long enough to retain two to four wrapper leaves. Extra leaves act as cushions during handling and may be desired in certain markets. Yellowed, damaged, or diseased wrapper leaves should be removed. Heads with insect damage and other defects should be discarded. In the case of pak choi types, any damaged or dead leaves should be removed and the base should be trimmed flush with the first petiole. Cabbage should be put in baskets or well-ventilated picking containers and taken out of the field immediately after harvest. Cabbage put in non-ventilated field sacks will heat up due to tissue respiration and start to wilt. It is recommended that harvesting be conducted during the coolest time of the day, preferably in the morning when the head is most turgid. It is essential that heads not harvested be left undamaged because fields may be harvested as many as three times for maximum yield. Preparation for Market Harvested cabbage is particularly susceptible to wilting and should be removed from the field and direct sunlight as soon as possible. The cabbage should be taken to a wellventilated shaded area for packing and transport to market (Figure 17). When there is a delay of more than an hour or two between harvest and packing, a spray of clean water to the leaves can help prevent dehydration. A simple field packing station can be constructed from wooden poles and a sheet of polyethylene. Thatch over the roof will provide shade and keep the station cool. The structure should be oriented so that the roof overhang keeps out the majority of the suns rays.

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Fig 17. Harvested cabbage should be taken to a shaded, wellventilated packing area.

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Sorting Cabbage should be sorted according to size, shape, and compactness of the head. There are 3 established size categories (small, medium, large) for domestic marketing of cabbage, based on the weight of the head. Small sized heads weigh 0.8 kg (1.7 lb) or less, medium sized heads weigh between 0.9 kg and 1.4 kg (1.7 lb and 3 lb), and large sized cabbage heads weigh 1.5 kg (3 lb) or more. Only the cabbage with crisp and turgid leaves should be packed for market. The heads should be a colour typical of the cultivar (i.e. green, red, or pale yellow-green), firm, heavy for the size and free of insect, decay, seed stalk development and other defects. Packing Heading-type cabbages are generally packed in fiberboard cartons, wooden or wire-bound crates, or mesh bags holding about 23 kg (50 lb). Uniformity of head size and the proper count per carton are important. Normally 18 to 22 heads are packed in a 23 kg (50 lb) container. Cartons and crates are easier to stack and load and provide considerably more protection to the cabbage than mesh bags (Figure 21). Pak choi cabbage should be packed in fiberboard cartons usually Fig 21. Uniform sized cabbage packed in strong well-ventilated holding between 10 kg to 18 kg (22 lb to 40 lb), depending upon wooden crates. market preference. Pak choi may be bunched into groups of 3 to 5 plants using a string or rubber band. Care must be taken as plants bruise easily. Temperature Control The optimal storage temperature for all cabbage types is 0C (32F). This maintains a very low respiratory activity in the cabbage and greatly inhibits decay. Chinese cabbage is much more perishable than heading types and should be cooled within several hours after harvest and held as close to the ideal postharvest temperature of 0C (32F) as possible. The maximum market life of pak choi under ideal conditions is 2 weeks. At ambient temperatures the pak choi leaves will rapidly wilt and become unmarketable after only 1 to 2 days. The need for immediate cooling after harvest is not as necessary for heading types of cabbage. However, for maximum storage life, heading types should be cooled within a day after harvest. Market life at 0C will be 4 to 6 weeks. Deterioration of cabbage is accelerated under non-refrigerated temperatures and is associated with discolouration of the stem end, leaf wilting, loss of fresh green colour, and postharvest decay. Storing cabbage at ambient temperature will require extensive trimming of the leaves to maintain a marketable head. Relative Humidity Control Cabbage is a leafy vegetable susceptible to significant moisture loss and wilting after harvest. The high surface area and numerous openings in the leaf surface (stomates) make an easy route for tissue water loss. In order to minimize the loss of crispness and wilting of the leaves it is very important to maintain a high relative humidity (RH) in the storage atmosphere. The optimal RH for cabbage is 95%. Pak choi can be stored at 0 C (32F) for several weeks, as long as the relative humidity is greater than 85%.

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INTRODUCTION Cassava (Manihot esculenta Crantz) reportedly has two geographical centres of specialization. One area is in western and southern Mexico and parts of Guatemala and the other is in north eastern Brazil. Presently, cassava is grown through out the tropics. Guyana is one of these tropical countries in which cassava is cultivated.This crop is produced in all ten Regions of Guyana. The Regions of highest production are Regions 1, 8 and 9. In Guyana, cassava is used mainly for food. Nutritionally, cassava is primarily an energy source since it is an excellent supplier of calories. The roots also contain quantities of vitamin C, thiamine, riboflavin and niavcin. It should be noted, however, that boiling reduces vitamin C content by 50 to 70 percent. Processing into such products as farine reduces it by 75 percent or more. In terms or food preparation in Guyana, the simplest is boiling of the tubers. Cassava is also processed into farine, cassava bread and casareep. An industrial use of cassava, in Guyana, is as the raw material in starch production. There are several other uses of cassava. One of these is as animal feed. Its starch has uses in the food industry, for paper making, as a lubricant in oil wells and in the textile industry.

VARIETIES There are several cassava varieties under cultivation in Guyana. Some of these are Four Month, Brancha Butterstick, Uncle Mack, M Mex 59, Mex 52 and Bad Woman.ENVIRONMENTAL REQUIREMENTS Cassava is well adapted to rainfall ranging between 1000 and 3000 millimeters per year but it requires good drainage. One day of flooding on heavy soils can destroy the crop. Cassava is, however, highly tolerant of drought. The plant becomes dormant in the dry weather. When rains resume, it draws on its carbohydrate reserve to produce new leaves and the plant again becomes productive. This crop is grown on a range of soils but it needs light, deep soils that will enhance tuber development. In Guyana, cassava is grown mainly on soils rich in organic matter, on loamy soils and on sandy soils. CULTIVATION LAND PREPARATION Land preparation should be deep enough to accommodate the tubers of cassava. Since the crop cannot withstand water logged conditions, there should be adequate drainage. Soils should be ploughed and harrowed and adequate drains should be made. For lighter soils flat planting can be done. In heavier soils, however, ridging may be necessary to facilitate drainage.

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Insect Pests of Cassava in GuyanaCassava crops are grown mainly from stem cuttings in Guyana. Planted cuttings start to root from the soil-covered nodes, at the base of the axillarys buds and the stipule scars, some five days after planting. Two to four months after planting, storage roots start to develop by secondary thickening of a number of the adventitious roots. Economical damage by diseases, pests and weeds of cassava is relatively moderate, although white flies can be a menace in some regions, if the problem is not identified early, and remedial action not implemented in a timely manner. Correct identification of the pest and an understanding of its behaviour, including its most vulnerable stages would provide insights into its management. Care must be then taken if pesticide application is contemplated, since there is the likelihood of high residual levels remaining in the product after harvest if an inappropriate formulation is used. The following provide a detailed description of the pests and the nature of the damage caused by the pests. Appropriate management strategies that may be employed are also provided.

1. Cassava Mealybug(Phenococcus manihoti) (Homoptera:Pseudococcidae) In cassava and on Manihot spp, the pest causes leaf loss and weakens the stem planting material (Figure 1). Symptoms: Whole plant: dieback; dwarfing; seedling blight. Leaves: abnormal colours; abnormal forms; abnormal leaf fall; wilting; yellowed or dead; honeydew or sooty mould; leaves rolled or folded. Stems: witches broom; stunting or rosetting; dieback; distortion. Roots: reduced root system. Growing points: dieback; distortion. Cultural Control: Integrated Pest Management Field sanitation Crop rotation

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Fig 1. Symptom of cassava mealybug Biological Control: Use natural enemies such as predators, parasitoids and parasites e.g. ladybirds

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Cultural Control: Good field sanitation- rid the field of weeds and plant residues from previous crops. Integrated Pest Management Biological Control: The natural predator, lady bird beetle frequently feeds on aphids. When aphid population is low and lady bird beetles are present, there is no need for chemical control. Fig 3. Nymph and adult aphid Chemical Control: This may be applied when the population is high. A contact or stomach insecticide may be used such as: Fastac, Decis or Karate at 6mls to 4500mls water, Sevin 85% W.P. (Carbaryl) at 6grms to 4500 mls water or Malathion 57% E.C. at 15 mls to 4500 mls water. N.B. Sprays should be directed to underside/surfaces of leaves. When Sevin or Malathion is used, crops should not be harvested until 7 -10 days after application of the chemicals. In the case of Fastac, Decis or Karate, crops can be harvested within 3-5 days after chemical 4. Thripsapplication. (Frankliniella williamsi) (Thysanoptera: Thripidae) Symptoms Thrips are yellow, tiny, elongated insects about 1mm in length and can be found on the upper and lower surfaces of leaves (Fig 4). Infestations are more severe in the dry season. Both young and adult suck the sap from leaves and cause them to loose their colour (Figure 5). If attack occurs early, the young leaves become distorted. Older tissues become blotched and appear silvery or leathery in affected areas, thus hindering photosynthesis. Flowers and fruits are also affected. Infected fruits are discoloured, distorted and hardened. Thrips are also vectors of major viral diseas. The lifecycle maybe completed in about 14-21 days. Cultural Control: Good field sanitation- rid the field Fig 4. Adult thrips Fig 5. Damage caused of weeds and residues of all previous crops. by thrips Crop rotation- cultivation of crops (vegetables) which are not host to the pest. Overhead irrigation will help in reducing population of infestation during the dry season. An integrated approach is recommended for the management of thrips Chemical Control: Among the insecticides which may be used are Regent (Fipronil), Admire, Abamectin and Vydate L at 5 mls to 4500 mls water, to both surfaces of leaves for effective control. N.B. Spray should be directed to both surfaces of leaves for effective control.

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7. Gall Midge (Latrophobia brasiliensis) Diptera:CecidopmyiidaeSymptoms The gall midges are tiny flying insects (Figure 8). The name is derived from their inciting gall formation by plants, attacked by larvae of some species. Most are plant feeders but some are carnivores. They feed on flowers/flower buds, fruit, developing seed and decaying material. Galls are mostly found on leaves, buds and stems. A large number also feed on fungi (and is sometimes beneficial to agriculture).

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Fig 8. Larva & adult gall midge Cultural Control: Where possible, plant in dry areas. Establish fields in open locations and space plants to allow adequate ventilation. Control weeds beneath and around plants. Remove all fallen leaves from fields, bury or burn. Colour traps present a potential tactic for monitoring or mating disruption. Along with bio-control and other tactics, they form the basis of an IPM programme.

Chemical Control: Insecticides: Sevin, Trigard, Diazinon, Admire, Malathion Fungicides: Manzeb, Maneb, Ridomil Herbicides: Fusillade, Roundup, Gramoxone, Nabu-S

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9. Acoushi Ant (Atta sp.)

Acoushi ants are social insects, living in colonies (Figure 10), whose size may range, depending on the species, between a dozen individuals and several millions of individuals. There are at least three morphologically different forms: queens (fertile females), males and workers. Acoushi ants display various major feeding strategies. Leaves are cut and transferred to the nest (Fig 11). Fungus growers consume fungi that are cultured in special nest chambers on leaf parts collected by workers. Cultural Control: Integrated pest Management Chemical Control: Baiting is the recommended method for Acoushi ant control (Bait is formulated and packaged by NARI).

Fig 10. Active acoushi ant nest

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Fig 11. Leaf cutting in progress

Managment of Common Cassava Diseases in Guyana 1. Cassava Mosaic Disease (African Mosaic Virus)Cassava mosaic disease is caused by a virus which occurs inside cassava leaves and stems. Damage symptoms: The leaves of cassava plants with the disease are discolored with patches of normal green color mixed with light green, yellow, and white areas (Figure 12). This discoloration is known as chlorosis. When cassava mosaic attack is severe, the leaves are very small and distorted and the plants are stunted. The disease symptoms are more pronounced on younger plants.

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Method of spread: The main sources of the bacteria which causes cassava bacterial blight are cassava plants with the disease. The bacterium enters cassava plants through wounds and scratches on the stems and leaves. Insects can also transfer the pathogen to healthy plants. It multiplies and occurs in large numbers in the leaves and stems. Cassava bacterial blight is therefore spread by planting stem cuttings from plants with the disease symptoms. Dead cassava stems and leaves with the bacterium also serve as sources of the disease if they are not destroyed after root harvest. Control: Cultural Integrated Crop Management Field sanitation Crop rotation Use of disease free planting material

Chemical Control: Farm tools that are used to cut infected cassava plants should be cleaned with a bleach solution after use to prevent the bacterium on them from spreading to other plants. Use for vector control Fastac, Decis or Karate

Fig 13. Symptom of cassava Bacterial Blight

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3. Cassava Bud NecrosisCassava bud necrosis is caused by a fungus which occurs on the surface of stems and leaves. Damage symptoms: The disease appears as patches of a brown or grey fungal covering of the stem. The fungal matter covers buds which reduces their sprouting ability (Figure 14). Cultural Control: Integrated Crop Management Field sanitation Crop rotation Use of disease free planting material Chemical Control: Spray a fungal solution for fungus control Fig 14. Cassava bud necrosis Farm tools that are used to cut infected cassava plants should be cleaned with a bleach solution after use to prevent the fungus from spreading to other plants.

4. Leaf Spot Diseases

Cassava leaf spot diseases are caused by fungi. There are three different types, namely white leaf spot, brown leaf spot, and leaf blight. Damage symptoms: Cassava white leaf spot (Cercospora caribaea) disease appears as circular white or brownish-yellow spots on the upper leaf surfaces (Figure 15). Cassava brown leaf spot (Cercospora henningsii) disease appears as small brown spots with dark borders on the upper leaf surfaces. Under severe attack the infected leaves become yellow, dry, and die prematurely (Figure 15).

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Method of spread: The important sources of cassava root rot fungi are soils, cassava root and stem debris contaminated with the fungi. The fungi enter cassava plant through wounds caused by pests or farming tools. Cultural Control: Cassava plant debris in farms with the disease should be destroyed by burning. Integrated Crop Management Field sanitation Crop rotation Use of disease free planting material Chemical Control: Farm tillage tools used in cassava farms with the disease should be cleaned after use with a bleach solution. Spray a fungal solution.

Harvest Maturity IndicesTime after planting is a commonly used index for determining when to harvest cassava. Roots are typically sufficiently well-developed beginning 6 to 7 months after planting. Harvest maturity is based on the root size desired by the market. Harvest may be delayed until market, processing, or weather conditions are favourable. However, as the roots age beyond a year, they become woody and fibrous. Several randomly selected plants, representative of the entire field, should be harvested beginning 6 months after planting to determine the average root size. Foliage senescence and lower leaf yellowing can also be used as an indication of harvest maturity. When the lower foliage is distinctly yellow and some leaves have dried up, it is likely the plants are mature enough for the roots to be harvested. Harvest Methods Harvesting cassava roots is usually done by hand and is easier when the soil is moist. Harvesting is also easier if planting is on ridges or in beds and in loose or sandy soils, rather than on flat ground and in clay or heavy soils. To facilitate lifting of the roots out of the ground, the main stem of the plant is usually cut back to a height of 30 cm to 50 cm (12 in to 20 in). The stem is used as a handle to lift the roots out of the ground (Figure 17). In light soils, the roots are slowly drawn from the soil by pulling the stems or with the help of a kind of crowbar. In heavier soils or during the dry season, harvesting usually requires digging around the roots to free them prior to lifting the plant. While lifting, care should be taken not to break the roots or split the skin. Wounded tissue is an entry point for decay causing micro-organisms.Fig 17. A short section of the stem is used to lift cassava roots out of the ground.

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Storage The simplest means of preserving cassava is to delay harvesting and allow the roots to remain in the ground. However, cassava roots will become fibrous and woody with prolonged in-ground storage time and flavour may be impaired. Also, the longer the roots remain in the ground the more risk there is of insect, disease, or rodent attack. Harvested roots can also be stored in the ground buried in trenches or holes filled with a sand/soil mix at 15% moisture. It is necessary to keep these in-ground storage areas protected from heavy rain. Roots will typically lose about 20% of their original starch content after 2 months stored underground. Above-ground clamp silos are low-cost structures that generally work well for cassava storage. Roots are piled up on a layer of straw in conical heaps weighing between 300 kg to 500 kg (600 lb to .5 tons). The pile is covered with straw and soil and openings should be left for ventilation. It is possible to store cassava for up to 4 weeks without significant weight loss or decay (Figure 20). Another method of storing cassava is to place them in wooden crates containing damp sawdust. However, if the sawdust is too moist it promotes fungal growth and if it is too dry the roots deteriorate quickly. Lining the crates with perforated plastic prevents dehydration of the sawdust, resulting in a storage life of about 1 month.Fig 20. Cleaning and weed removalaround cassava storage structure.

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Cassava roots treated with the fungicide thiabendazole can be stored for 3 weeks inside perforated plastic bags at ambient temperatures. Keeping the roots inside plastic bags also reduces the incidence of vascular streaking. Various types of above-ground storage structures can be built for extending cassava postharvest life. The structures should be located in shaded areas free from standing water during heavy rains. A simple storage facility can be constructed from unfinished wooden planks painted white to reduce heat accumulation and covered with a thatched roof for protection against the sun and rain. The structure has a large door on one side for loading and unloading. It is designed for holding between 1 to 2 tons (1000 kg to 2000 kg) of cassava. A brick or concrete floor is recommended for permanent storage buildings and the structure should have a large door for loading and unloading. A tin or shingled roof is ideal, and the structure should have good ventilation. The doors should be secured against rodent entry and theft. Postharvest Temperature Refrigerated storage may not be an economical, viable method for extending the postharvest life of domestically marketed cassava, but is typically necessary for roots intended for high-value export markets. Fresh cassava roots are highly perishable at normal air temperatures, often becoming unmarketable after several days to a week.

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Soils It is possible to grow West Indian cherries in a wide range of soil types. However, highest yields are obtained from trees growing on well drained soils with more or less neutral reaction i.e. neither acid (sour) or alkaline (sweet). Given that most of the soils in Guyana are acid in reaction, a significant response can be expected from liming, which is the main way of reducing soil acidity. In sandy soils, the plant may be affected by nematodes which live in the soil. The recommended practice to overcome this is treatment of the soil with a nematicide. However, liming and the use of mulches will also be helpful. Field layout, land shaping, drainage systems, planting hole preparation, plant spacing and time of planting depend on the area where the planting will be done. The characteristics of cultivars to be planted (upright and open or spreading and bushy canopy) and the type of planting material (rooted cuttings or seedlings) are also important considerations.. Wide inter row spacing, narrow cambered beds, deep drains, raised mounds, are some of the possible measures that may be adopted for overcoming adverse field conditions. Planting just before the onset of the rainy season is the recommended practice. It may be possible to plant continuously, if supplementary irrigation is available during the drier seasons. Planting Cherry seedlings are ready for planting out in the field when they are about 46 cm (18 ins) high. Planting should be conducted during the wet season while there is still moisture in the topsoil. The recommended spacing for pure stand cultivation is 4.5 m x 4.5 m (15 x 15) giving a population of 500 plants per hectare (200 plants per acre). For mixed stands or intercropping systems, a lower plant population may be necessary, Planting holes are dug to a size to accommodate the plant in the bag but usually around 30 cm (1 ft.) in length, width and depth. The topsoil removed in digging the plant hole could be mixed with rotted pen manure, compost or some phosphate fertiliser. Some of this mixed soil is then returned to the planting hole before putting the plant. The plant bags in which plants are usually supplied should be carefully removed so as to keep the root ball intact. The plants are then placed in the holes following which the balance of the topsoil is returned to fill the holes and thoroughly compressed. If conditions are dry the plants should be watered. As part of their cultivation system, growers need to consider Intercropping Closer spacing & subsequent thinning out to the required spacing.

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Harvest The Cherry plant usually comes into fruiting about 2-3 years after transplanting depending on the size of the plants after transplanting. Rooted cuttings can produce much earlier with the first important crop produced 18 -24 months after planting. Successive annual yields increase, peaking at 4-5 years after planting. Healthy 6-year old trees have been reported to yield 15 kg per tree per annum. This soft fruit is harvested by hand picking. However, systems of using tractor hauled hydraulic shakers with fruits being collected on tarpaulin or plastic sheeting spread under the trees have been tried elsewhere. In some large operations, all fruits are picked at the same time. This has several advantages, especially for the management of labour, timing and standardization of field operations; and optimising yield potential by reducing damage to new flowers. It also improves Vitamin C content since green fruits have a higher concentration of ascorbic acid than ripe fruits. Post Harvest Handling High losses are to be expected if sufficient care is not taken when picking and handling. This may be of minor importance if the fruits are to be used shortly after harvesting. If fruits are to be stored for longer periods before use, then refrigeration (for 3-5 days storage) or freezing (for more than 7 days storage) are recommended. In all cases, it is important to store in the shade because exposure to direct sunlight lowers ascorbic acid content, alters flavour and leads to undesirable colour changes. Fruits should be stored in open crates or baskets, which provide good ventilation. Bags provide poor ventilation and storage in bags should be avoided.

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Introduction Chive is a member of the Allium family (Alliaceae) which includes other crops such as eschallot, onion, garlic, leek and bunching onion. The chive is the most widely distributed of the Allium species. The crop is a perennial, but in Guyana it is cultivated as an annual where the entire plant is harvested after an eight week growing cycle. Compared to onions and other alliums, chives have a strong tillering habit, forming dense clumps without well-formed bulbs.

Chives are grown mainly to satisfy the domestic market in Guyana. The herb has culinary and medicinal properties. The fresh leaves are used for making herbal butters and vinegar as well as a flavouring in salads, soups and soft cheeses. The oils (leaf extract) of the plant are known to lower blood levels of low-density lipoproteins. Chives contain some iron and vitamins and can be used as mild antibiotics and laxative. The plants can also be grown for their attractive pinkish to mauve fragrant flowers.

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Cultivation Soil Chives are tolerant to a wide range of soil conditions but fertile, well-drained medium loams with a pH of 6.0 - 7.0 are generally considered most suitable. Sandy soils can also be used if organic matter (30-40 tons/ha) is incorporated. Clay soils need good drainage as well as organic matter (well-rotted pen manure) to improve the soil structure and fertility.

Land preparation Chive is a shallow rooted crop (25-30 cm), so land preparation should not be deep. For virgin lands, plough the land twice down and across the field, to a depth of 20-25 cm, and harrow to obtain a fine tilth. Form beds 120 cm wide and 20 cm high. For continuously cultivated lands, fork and rake the land before planting. If nut grass, Cyperus rotundus, is present at land preparation, use Roundup at 3-4 tbs/gal 7-14 days before planting. The chemical is most effective when the weeds are actively growing.

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Irrigation Chives respond well to regular irrigation, especially in the dry seasons. Watering in the morning is highly recommended.

Weed Control Chive is poor competitor with weeds for water and soil nutrients - due to its shallow fibrous root system and the lack of an aerial canopy to shade out other vegetation. Chive is affected by many weeds but Hog bhagee, Portulaca oleracea L. is of major economic importance. It affects the plant from a very early stage; it grows vigorously competing with the plant and if not controlled, especially during the first three weeks of crop growth, it will smother the plants. P. oleracea can be controlled effectively with the broadleaf-specific chemical, Runstar at15 ml/2-3 gal water. Since this chemical does not affect straight vein weeds such as grasses, the most suitable method of control is removal by hand.

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Insect Pests and Their Control Chive is subject to pest attacks like any other crop. Daily inspection is recommended for insect pests. This should be done in the early morning or late afternoon. Apply insecticides only when the pests are present at levels that can reduce returns of the crop.

1. Leafminer, Liriomyza sp.

Economically, this is the most important pest affecting chive cultivation on the coast. The larvae of the leafminer feed between the leaf surfaces leaving irregular patterns of greenish-white mines on the leaves. This pest occurs year-round and it indiscriminately attacks plants of all stages of the crop cycle. Serious infestation causes yellowing, and subsequently browning of infected leaves.

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Control Apply any one of the following: a) Leaf Guard (IGR) 75%. Mix 7g/18 litres water. For high insect population, repeat every seven days, for normal levels repeat every 14 to 21 days. Pre-harvest interval is seven to ten days. b) Padan 50 WSP. Mix 15 g in 4 to5 litres of water. Ensure a seven day interval between applications. Pre-harvest interval is ten days. c) Trigard 75% WP. Mix 2 g/3.8 litres water. It is advisable to alternate these chemicals to prevent the pest from developing resistance to the chemicals.

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2. Crickets Mole crickets, Scapteriscus spp. are present year-round and attack the crop indiscriminately. Crickets bite through the pseudostem of the chive destroying the entire plant. This is common during the first two weeks of planting. Control A bait comprising 0.9 kg (2 lb) freshly grated coconut and 3 ounces malathion and small handful of sugar or 2 tablespoons of molasses can be used to control crickets. This mixture is applied in the evening and evidence of control can be noticed the morning after. This method is highly effective in controlling the pest and one application is necessary per crop cycle.

The pest can also be controlled by any of the following: Diazinon (Contact) Fastac (Contact) Admire (Systemic) Fendona (Contact) 1-2 tbsp/4.5 L 1-2 tsp/4.5 L (1-2 tbsp/gal) (1-2 tsp/gal)

28.4-85.2 g/4.5 L (1-3 oz/gal) 28.4-113.1 g/4.5 L (1-4 oz/gal) (2-3 tsp/gal)

Padan (Contact - ingestion) 2-3 tsp/4.5 L

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Post-harvest Management Chive is a highly perishable crop and should therefore reach the market within 24 hours of harvesting. If refrigerated conditions are available, this can extend to 48 hours. Storing at 0-1oC at 95-100% relative humidity can extend the shelf life of chives for 7-14 days.

Flow Diagram of Post-Harvest Handling System For Chives

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In the main, Rootstocks are chosen for resistance to diseases, adaptability to soil type, quality and yield of fruit. Nowadays, the primary selection of rootstocks is made for resistance to Tristeza, which is considered the most destructive virus disease of citrus. The Tristeza-resistant rootstocks which are suitable for conditions in Guyana are Carizzo Citrange, Cleopatra Mandarin, Rangpur Lime, Rough Lemon, Swingle Citrumelo and Volkameriana Lemon. However, as each of the rootstocks varies regarding resistance to additional virus diseases as well as to the other factors mentioned, it is recommended that every estate should have plants on more than one type of rootstock. A limited amount of budded Citrus plants primarily on Rough Lemon rootstock, are usually available from the NARI Nurseries, Also, plans are in place to produce Tristeza-free plants in the not to distant future. However, growers of large areas are encouraged to produce their own plants. Seeds are extracted from the fruit of the selected rootstock (e.g. Rough Lemon washed to remove slime, dried at room temperature, soak for 10 minutes at 49-52OC then treated with a fungicide (e.g.) Captan) and stored moist in polythene bag at 4OC, 40OF for not too excessive a time un