We know that all living organisms need food.Food supplies proteins, carbohydrates, fats,vitamins and minerals, all of which we requirefor body development, growth and health.Both plants and animals are major sourcesof food for us. We obtain most of this foodfrom agriculture and animal husbandry.

We read in newspapers that efforts arealways being made to improve productionfrom agriculture and animal husbandry. Whyis this necessary? Why we cannot make dowith the current levels of production?

India is a very populous country. Ourpopulation is more than one billion people,and it is still growing. As food for this growingpopulation, we will soon need more than aquarter of a billion tonnes of grain every year.This can be done by farming on more land.But India is already intensively cultivated. Asa result, we do not have any major scope forincreasing the area of land under cultivation.Therefore, it is necessary to increase ourproduction efficiency for both crops andlivestock.

Efforts to meet the food demand byincreasing food production have led to somesuccesses so far. We have had the greenrevolution, which contributed to increasedfood-grain production. We have also had thewhite revolution, which has led to better andmore efficient use as well as availability of milk.

However, these revolutions mean that ournatural resources are getting used moreintensively. As a result, there are morechances of causing damage to our naturalresources to the point of destroying theirbalance completely. Therefore, it is importantthat we should increase food productionwithout degrading our environment anddisturbing the balances maintaining it.

Hence, there is a need for sustainablepractices in agriculture and animalhusbandry.

Also, simply increasing grain productionfor storage in warehouses cannot solve theproblem of malnutrition and hunger. Peopleshould have money to purchase food. Foodsecurity depends on both availability of foodand access to it. The majority of ourpopulation depends on agriculture for theirlivelihood. Increasing the incomes of peopleworking in agriculture is therefore necessaryto combat the problem of hunger. Scientificmanagement practices should be undertakento obtain high yields from farms. Forsustained livelihood, one should undertakemixed farming, intercropping, and integratedfarming practices, for example, combineagriculture with livestock/poultry/fisheries/bee-keeping.

The question thus becomes how do weincrease the yields of crops and livestock?

15.1 Improvement in Crop YieldsCereals such as wheat, rice, maize, milletsand sorghum provide us carbohydrate forenergy requirement. Pulses like gram (chana),pea (matar), black gram (urad), green gram(moong), pigeon pea (arhar), lentil (masoor),provide us with protein. And oil seedsincluding soyabean, ground nut, sesame,castor, mustard, linseed and sunflowerprovide us with necessary fats (Fig. 15.1).Vegetables, spices and fruits provide a rangeof vitamins and minerals in addition to smallamounts of proteins, carbohydrates and fats.In addition to these food crops, fodder cropslike berseem, oats or sudan grass are raisedas food for the livestock.

15IIIIIMPROVEMENTMPROVEMENTMPROVEMENTMPROVEMENTMPROVEMENT INININININ F F F F FOODOODOODOODOOD R R R R RESOURCESESOURCESESOURCESESOURCESESOURCES

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the kharif season from the month of June toOctober, and some of the crops are grown inthe winter season, called the rabi season fromNovember to April. Paddy, soyabean, pigeonpea, maize, cotton, green gram and blackgram are kharif crops, whereas wheat, gram,peas, mustard, linseed are rabi crops.

In India there has been a four timesincrease in the production of food grains from1952 to 2010 with only 25% increase in thecultivable land area. How has this increasein production been achieved? If we think ofthe practices involved in farming, we can seethat we can divide it into three stages. Thefirst is the choice of seeds for planting. Thesecond is the nurturing of the crop plants.The third is the protection of the growing andharvested crops from loss. Thus, the majorgroups of activities for improving crop yieldscan be classified as:

Crop variety improvement Crop production improvement Crop protection management.

15.1.1 CROP VARIETY IMPROVEMENTThis approach depends on finding a cropvariety that can give a good yield. Varieties orstrains of crops can be selected by breedingfor various useful characteristics such asdisease resistance, response to fertilisers,product quality and high yields. One way ofincorporating desirable characters into cropvarieties is by hybridisation. Hybridisationrefers to crossing between geneticallydissimilar plants. This crossing may beintervarietal (between different varieties),interspecific (between two different species ofthe same genus) or intergeneric (betweendifferent genera). Another way of improvingthe crop is by introducing a gene that wouldprovide the desired characteristic. Thisresults in genetically modified crops.

For new varieties of crops to be accepted,it is necessary that the variety produces highyields under different conditions that arefound in different areas. Farmers would needto be provided with good quality seeds of aparticular variety, that is, the seeds should

Fig. 15.1: Different types of crops

uestion1. What do we get from cereals,

pulses, fruits and vegetables?

Different crops require different climaticconditions, temperature and photoperiods fortheir growth and completion of their life cycle.Photoperiods are related to the duration ofsunlight. Growth of plants and flowering aredependent on sunlight. As we all know, plantsmanufacture their food in sunlight by theprocess of photosynthesis. There are somecrops, which are grown in rainy season, called

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all be of the same variety and germinate underthe same conditions.

Cultivation practices and crop yield arerelated to weather, soil quality and availabilityof water. Since weather conditions such asdrought and flood situations areunpredictable, varieties that can be grown indiverse climatic conditions are useful.Similarly, varieties tolerant to high soil salinityhave been developed. Some of the factors forwhich variety improvement is done are:

Higher yield: To increase theproductivity of the crop per acre.

Improved quality: Qualityconsiderations of crop products varyfrom crop to crop. Baking quality isimportant in wheat, protein quality inpulses, oil quality in oilseeds andpreserving quality in fruits andvegetables.

Biotic and abiotic resistance: Cropsproduction can go down due to biotic(diseases, insects and nematodes) andabiotic (drought, salinity, waterlogging, heat, cold and frost) stressesunder different situations. Varietiesresistant to these stresses can improvecrop production.

Change in maturity duration: Theshorter the duration of the crop fromsowing to harvesting, the moreeconomical is the variety. Such shortdurations allow farmers to growmultiple rounds of crops in a year.Short duration also reduces the costof crop production. Uniform maturitymakes the harvesting process easyand reduces losses during harvesting.

Wider adaptability: Developingvarieties for wider adaptability willhelp in stabilising the crop productionunder different environmentalconditions. One variety can then begrown under dif ferent climaticconditions in different areas.

Desirable agronomic characteristics:Tallness and profuse branching aredesirable characters for fodder crops.Dwarfness is desired in cereals, so

that less nutrients are consumed bythese crops. Thus developing varietiesof desired agronomic characters helpgive higher productivity.

uestions1. How do biotic and abiotic factors

affect crop production?2. What are the desirable agronomic

characteristics for cropimprovements?

15.1.2 CROP PRODUCTION MANAGEMENTIn India, as in many other agriculture-basedcountries, farming ranges from small to verylarge farms. Different farmers thus have moreor less land, money and access to informationand technologies. In short, it is the money orfinancial conditions that allow farmers to takeup different far ming practices andagricultural technologies. There is acorrelation between higher inputs and yields.Thus, the farmers purchasing capacity forinputs decides cropping system andproduction practices. Therefore, productionpractices can be at different levels. Theyinclude no cost production, low costproduction and high cost productionpractices.

15.1.2 (i) NUTRIENT MANAGEMENTJust as we need food for development, growthand well-being, plants also require nutrientsfor growth. Nutrients are supplied to plantsby air, water and soil. There are sixteennutrients which are essential for plants. Airsupplies carbon and oxygen, hydrogen comesfrom water, and soil supplies the otherthirteen nutrients to plants. Amongst thesethirteen nutrients, six are required in largequantities and are therefore called macro-nutrients. The other seven nutrients are usedby plants in small quantities and are thereforecalled micro-nutrients (Table 15.1).

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our environment from excessive use offertilizers. Using biological waste material isalso a way of recycling farm waste. Based onthe kind of biological material used, manurecan be classified as:

(i) Compost and vermi-compost: Theprocess in which farm waste materiallike livestock excreta (cow dung etc.),vegetable waste, animal refuse,domestic waste, sewage waste, straw,eradicated weeds etc. is decomposedin pits is known as composting. Thecompost is rich in organic matter andnutrients. Compost is also preparedby using earthworms to hasten theprocess of decomposition of plant andanimal refuse. This is called vermi-compost.

(ii) Green manure: Prior to the sowing ofthe crop seeds, some plants like sunhemp or guar are grown and thenmulched by ploughing them into thesoil. These green plants thus turn intogreen manure which helps inenriching the soil in nitrogen andphosphorus.

FERTILIZERSFertilizers are commercially produced plantnutrients. Fertilizers supply nitrogen,phosphorus and potassium. They are usedto ensure good vegetative growth (leaves,branches and flowers), giving rise to healthyplants. Fertilizers are a factor in the higheryields of high-cost farming.

Fertilizers should be applied carefully interms of proper dose, time, and observing pre-and post-application precautions for theircomplete utilisation. For example, sometimesfertilizers get washed away due to excessiveirrigation and are not fully absorbed by theplants. This excess fertilizer then leads towater pollution.

Also, as we have seen in the previouschapter, continuous use of fertilizers in anarea can destroy soil fertility because theorganic matter in the soil is not replenishedand micro-organisms in the soil are harmedby the fertilizers used. Short-term benefits ofusing fertilizers and long-term benefits of

Deficiency of these nutrients affectsphysiological processes in plants includingreproduction, growth and susceptibility todiseases. To increase the yield, the soil canbe enriched by supplying these nutrients inthe form of manure and fertilizers.

uestions1. What are macro-nutrients and

why are they called macro-nutrients?

2. How do plants get nutrients?

MANUREManure contains large quantities of organicmatter and also supplies small quantities ofnutrients to the soil. Manure is prepared bythe decomposition of animal excreta and plantwaste. Manure helps in enriching soil withnutrients and organic matter and increasingsoil fertility. The bulk of organic matter inmanure helps in improving the soil structure.This involves increasing the water holdingcapacity in sandy soils. In clayey soils, thelarge quantities of organic matter help indrainage and in avoiding water logging.

In using manure we use biological wastematerial, which is advantageous in protecting

Table 15.1: Nutrients suppliedby air, water and soil

Source Nutrients

Air carbon, oxygen

Water hydrogen, oxygen

Soil (i) Macronutrients:nitrogen, phosphorus,potassium, calcium,magnesium, sulphur

(ii) Micronutrients:iron, manganese, boron,zinc, copper,molybdenum, chlorine

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India has a wide variety of water resourcesand a highly varied climate. Under suchconditions, several different kinds of irrigationsystems are adopted to supply water toagricultural lands depending on the kinds ofwater resources available. These includewells, canals, rivers and tanks.

Wells: There are two types of wells,namely dug wells and tube wells. In adug well, water is collected from waterbearing strata. Tube wells can tapwater from the deeper strata. Fromthese wells, water is lifted by pumpsfor irrigation.

Canals: This is usually an elaborateand extensive irrigation system. In thissystem canals receive water from oneor more reservoirs or from rivers. Themain canal is divided into branchcanals having further distributaries toirrigate fields.

River Lift Systems: In areas wherecanal flow is insufficient or irregulardue to inadequate reservoir release,the lift system is more rational. Wateris directly drawn from the rivers forsupplementing irrigation in areasclose to rivers.

Tanks: These ar e small storagereservoirs, which intercept and storethe run-of f of smaller catchmentareas.

Fresh initiatives for increasing the wateravailable for agriculture include rainwaterharvesting and watershed management. Thisinvolves building small check-dams whichlead to an increase in ground water levels.The check-dams stop the rainwater fromflowing away and also reduce soil erosion.

15.1.2 (iii) CROPPING PATTERNSDifferent ways of growing crops can be usedto give maximum benefit.

Mixed cropping is growing two or morecrops simultaneously on the same piece ofland, for example, wheat + gram, or wheat +mustard, or groundnut + sunflower. Thisreduces risk and gives some insuranceagainst failure of one of the crops.

using manure for maintaining soil fertility haveto be considered while aiming for optimumyields in crop production.

uestion1. Compare the use of manure and

fertilizers in maintaining soilfertility.

Organic farming is a farming system withminimal or no use of chemicals as fertilizers,herbicides, pesticides etc. and with amaximum input of organic manures, recycledfarm-wastes (straw and livestock excreta), useof bio-agents such as culture of blue greenalgae in preparation of biofertilizers, neemleaves or turmeric specifically in grain storageas bio-pesticides, with healthy croppingsystems [mixed cropping, inter-cropping andcrop rotation as discussed below in15.1.2.(iii)]. These cropping systems arebeneficial in insect, pest and wheat controlbesides providing nutrients.

15.1.2 (ii) IRRIGATIONMost agriculture in India is rain-fed, that is,the success of crops in most areas isdependent on timely monsoons and sufficientrainfall spread through most of the growingseason. Hence, poor monsoons cause cropfailure. Ensuring that the crops get water atthe right stages during their growing seasoncan increase the expected yields of any crop.Therefore, many measures are used to bringmore and more agricultural land underirrigation.

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Droughts occur because of scarcity orirregular distribution of rains. Droughtposes a threat to rain-fed farmingareas, where farmers do not useirrigation for crop production anddepend only on rain. Light soils haveless water retention capacity. In areaswith light soils, crops get adverselyaf fected by drought conditions.Scientists have developed some cropvarieties which can tolerate droughtconditions.

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Inter-cropping is growing two or morecrops simultaneously on the same field in adefinite pattern (Fig.15.2). A few rows of onecrop alternate with a few rows of a secondcrop, for example, soyabean + maize, or fingermillet (bajra) + cowpea ( lobia). The crops areselected such that their nutrientrequirements are different. This ensuresmaximum utilisation of the nutrientssupplied, and also prevents pests anddiseases from spreading to all the plantsbelonging to one crop in a field. This way,both crops can give better returns.

(gokhroo), Parthenium (gajar ghas ),Cyperinus rotundus (motha ). They competefor food, space and light. Weeds take upnutrients and reduce the growth of the crop.Therefore, removal of weeds from cultivatedfields during the early stages of crop growth isessential for a good harvest.

Generally insect pests attack the plantsin three ways: (i) they cut the root, stem andleaf, (ii) they suck the cell sap from variousparts of the plant, and (iii) they bore into stemand fruits. They thus affect the health of thecrop and reduce yields.

Diseases in plants are caused bypathogens such as bacteria, fungi and viruses.These pathogens can be present in andtransmitted through the soil, water and air.

Weeds, insects and diseases can becontrolled by various methods. One of themost commonly used methods is the use ofpesticides, which include herbicides,insecticides and fungicides. These chemicalsare sprayed on crop plants or used for treatingseeds and soil. However, excessive use ofthese chemicals creates problems, since theycan be poisonous to many plant and animalspecies and cause environmental pollution.

Weed control methods also includemechanical removal. Preventive methodssuch as proper seed bed preparation, timelysowing of crops, intercropping and croprotation also help in weed control. Some otherpreventive measures against pests are the useof resistant varieties, and summer ploughing,in which fields are ploughed deep in summersto destroy weeds and pests.

uestion1. Which of the following conditions

will give the most benefits? Why?(a) Farmers use high-quality

seeds, do not adoptirrigation or use fertilizers.

(b) Farmers use ordinaryseeds, adopt irrigation anduse fertilizer.

(c) Farmers use quality seeds,adopt irrigation, usefertilizer and use cropprotection measures.

QFig. 15.2 : Intercropping

The growing of different crops on a pieceof land in a pre-planned succession is knownas crop rotation. Depending upon theduration, crop rotation is done for differentcrop combinations. The availability ofmoisture and irrigation facilities decide thechoice of the crop to be cultivated after oneharvest. If crop rotation is done properly thentwo or three crops can be grown in a yearwith good harvests.

15.1.3 CROP PROTECTION MANAGEMENTField crops are infested by a large number ofweeds, insect pests and diseases. If weeds andpests are not controlled at the appropriatetime then they can damage the crops so muchthat most of the crop is lost.

Weeds are unwanted plants in thecultivated field, for example, Xanthium

IMPROVEMENT IN FOOD RESOURCES 209

Activity _____________15.1 Visit a weed-infested field in the month

of July or August and make a list ofthe weeds and insect pests in the field.

STORAGE OF GRAINSStorage losses in agricultural produce can bevery high. Factors responsible for such lossesare biotic insects, rodents, fungi, mites andbacteria, and abiotic inappropriatemoisture and temperatures in the place ofstorage. These factors cause degradation inquality, loss in weight, poor germinability,discolouration of produce, all leading to poormarketability. These factors can be controlledby proper treatment and by systematicmanagement of warehouses.

Preventive and control measures are usedbefore grains are stored for future use. Theyinclude strict cleaning of the produce beforestorage, proper drying of the produce first insunlight and then in shade, and fumigationusing chemicals that can kill pests.

uestions1. Why should preventive measures

and biological control methods bepreferred for protecting crops?

2. What factors may be responsiblefor losses of grains duringstorage?

Activity _____________15.2 Make a herbarium of cereals, pulses

and oil seeds and identify the seasonsof their sowing and harvesting.

15.2 Animal HusbandryAnimal husbandry is the scientificmanagement of animal livestock. It includesvarious aspects such as feeding, breeding anddisease control. Animal-based farmingincludes cattle, goat, sheep, poultry and fishfarming. As the population increases and asliving standards increase, the demand formilk, eggs and meat is also going up. Also,the growing awareness of the need forhumane treatment of livestock has broughtin new limitations in livestock farming. Thus,livestock production also needs to beimproved.

15.2.1 CATTLE FARMING

Cattle husbandry is done for two purposesmilk and draught labour for agricultural worksuch as tilling, irrigation and carting. Indiancattle belong to two different species, Bosindicus, cows, and Bos bubalis, buffaloes.Milk-producing females are called milchanimals (dairy animals), while the ones usedfor farm labour are called draught animals.

Milk production depends, to some extent,on the duration of the lactation period,meaning the period of milk production after

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Table 15.2: Nutritional values of animal products

AnimalProducts

Fat Protein Sugar Minerals Water Vitamins

Milk (Cow) 3.60 4.00 4.50 0.70 87.20 B1, B2, B12, D, E

Egg 12.00 13.00 * 1.00 74.00 B2, D

Meat 3.60 21.10 * 1.10 74.20 B2, B12

Fish 2.50 19.00 * 1.30 77.20 Niacin, D, A

*Present in very small amounts

Per cent (%) Nutrients

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the birth of a calf. So, milk production can beincreased by increasing the lactation period.Exotic or foreign breeds (for example, Jersey,Brown Swiss) are selected for long lactationperiods, while local breeds (for example, RedSindhi, Sahiwal) show excellent resistance todiseases. The two can be cross-bred to getanimals with both the desired qualities.

uestion1. Which method is commonly used

for improving cattle breeds andwhy?

Activity _____________15.3 Visit a livestock farm. Note the

following:(1) Number of cattle and number of

different breeds.(2) The amount of daily milk production

from the different breeds.

Proper cleaning and shelter facilities forcows and buffaloes are required for humanefarming, for the health of the animals andfor production of clean milk as well. Animalsrequire regular brushing to remove dirt and

loose hair. They should be sheltered underwell-ventilated roofed sheds that protect themfrom rain, heat and cold. The floor of the cattleshed needs to be sloping so as to stay dryand to facilitate cleaning.

The food requirements of dairy animalsare of two types: (a) maintenancerequirement, which is the food required tosupport the animal to live a healthy life, and(b) milk producing requirement, which is thetype of food required during the lactationperiod. Animal feed includes: (a) roughage,which is largely fibre, and (b) concentrates,which are low in fibre and contain relativelyhigh levels of proteins and other nutrients.Cattle need balanced rations containing allnutrients in proportionate amounts. Besidessuch nutritious food material, certain feedadditives containing micronutrients promotethe health and milk output of dairy animals.

Cattle suffer from a number of diseases.The diseases, besides causing death, reducemilk production. A healthy animal feedsregularly and has a normal posture. Theparasites of cattle may be both externalparasites and internal parasites. The externalparasites live on the skin and mainly causeskin diseases. The internal parasites likeworms, affect stomach and intestine whileflukes damage the liver. Infectious diseasesare also caused by bacteria and viruses.Vaccinations are given to farm animalsagainst many major viral and bacterialdiseases.

15.2.2 POULTRY FARMINGPoultry farming is undertaken to raisedomestic fowl for egg production and chickenmeat. Therefore, improved poultry breeds aredeveloped and farmed to produce layers foreggs and broilers for meat.

The cross-breeding programmes betweenIndian (indigenous, for example, Aseel) andforeign (exotic, for example, Leghorn) breedsfor variety improvement are focused on todevelop new varieties for the followingdesirable traits

(i) number and quality of chicks;

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Fig. 15.3: Indigenous milch breed of cattle

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(ii) dwarf broiler parent for commercialchick production;

(iii) summer adaptation capacity/tolerance to high temperature;

(iv) low maintenance requirements;(v) reduction in the size of the egg-laying

bird with ability to utilise morefibrous cheaper diets formulatedusing agricultural by-products.

The ration (daily food requirement) for broilersis protein rich with adequate fat. The level ofvitamins A and K is kept high in the poultryfeeds.

Poultry fowl suffer from a number ofdiseases caused by virus, bacteria, fungi,parasites, as well as from nutritionaldeficiencies. These necessitate propercleaning, sanitation, and spraying ofdisinfectants at regular intervals. Appropriatevaccination can prevent the occurrence ofinfectious diseases and reduce loss of poultryduring an outbreak of disease.

uestions1. What management practices are

common in dairy and poultryfarming?

2. What are the differences betweenbroilers and layers and in theirmanagement?

Activity _____________15.4 Visit a local poultry farm. Observe types

of breeds and note the type of ration,housing and lighting facilities given tothem. Identify the growers, layers andbroilers.

15.2.3 FISH PRODUCTIONFish is a cheap source of animal protein forour food. Fish production includes the finnedtrue fish as well as shellfish such as prawnsand molluscs. There are two ways of obtainingfish. One is from natural resources, which iscalled capture fishing. The other way is byfish farming, which is called culture fishery.

The water source of the fish can be eitherseawater or fresh water, such as in rivers andponds. Fishing can thus be done both bycapture and culture of fish in marine andfreshwater ecosystems.

15.2.3 (i) MARINE FISHERIESIndias marine fishery resources include7500 km of coastline and the deep seas

Fig. 15.4

Aseel Leghorn

uestion1. Discuss the implications of the

following statement:It is interesting to note thatpoultry is Indias most efficientconverter of low fibre food stuff(which is unfit for humanconsumption) into highlynutritious animal protein food.

EGG AND BROILER PRODUCTIONBroiler chickens are fed with vitamin-richsupplementary feed for good growth rate andbetter feed efficiency. Care is taken to avoidmortality and to maintain feathering andcarcass quality. They are produced as broilersand sent to market for meat purposes.

For good production of poultry birds, goodmanagement practices are important. Theseinclude maintenance of temperature andhygienic conditions in housing and poultryfeed, as well as prevention and control ofdiseases and pests.

The housing, nutritional andenvironmental requirements of broilers aresomewhat different from those of egg layers.

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beyond it. Popular marine fish varietiesinclude pomphret, mackerel, tuna, sardines,and Bombay duck. Marine fish are caughtusing many kinds of fishing nets from fishingboats. Yields are increased by locating largeschools of fish in the open sea using satellitesand echo-sounders.

Some marine fish of high economic valueare also farmed in seawater. This includesfinned fishes like mullets, bhetki, and pearlspots, shellfish such as prawns (Fig. 15.5),mussels and oysters as well as seaweed.Oysters are also cultivated for the pearlsthey make.

Macrobrachium rosenbergii(fresh water)

Peneaus monodon(marine)

Fig. 15.5 : Fresh water and marine prawns

As marine fish stocks get further depleted,the demand for more fish can only be met bysuch culture fisheries, a practice calledmariculture.

15.2.3 (ii) INLAND FISHERIESFresh water resources include canals, ponds,reservoirs and rivers. Brackish waterresources, where seawater and fresh watermix together, such as estuaries and lagoonsare also important fish reservoirs. Whilecapture fishing is also done in such inlandwater bodies, the yield is not high. Most fishproduction from these resources is throughaquaculture.

Fish culture is sometimes done incombination with a rice crop, so that fish aregrown in the water in the paddy field. Moreintensive fish farming can be done incomposite fish culture systems. Both localand imported fish species are used in suchsystems.

In such a system, a combination of five orsix fish species is used in a single fishpond.These species are selected so that they donot compete for food among them havingdifferent types of food habits. As a result, thefood available in all the parts of the pond isused. As Catlas are surface feeders, Rohusfeed in the middle-zone of the pond, Mrigalsand Common Carps are bottom feeders, andGrass Carps feed on the weeds, together thesespecies (Fig. 15.6) can use all the food in thepond without competing with each other. Thisincreases the fish yield from the pond.

(a)(b)

(c)(d)

Fig. 15.6: (a) Catla (b) Silver carp (c) Rohu (d) GrassCarp (e) Mrigal (f) Common Carp

(e)

(f)

One problem with such composite fishculture is that many of these fish breed onlyduring monsoon. Even if fish seed is collectedfrom the wild, it can be mixed with that ofother species as well. So, a major problem infish farming is the lack of availability of good-quality seed. To overcome this problem, wayshave now been worked out to breed these fishin ponds using hormonal stimulation. Thishas ensured the supply of pure fish seed indesired quantities.

IMPROVEMENT IN FOOD RESOURCES 213

uestions1. How are fish obtained?2. What are the advantages of

composite fish culture?

Activity _____________15.5 Visit a fish farm in fish breeding

season and note the following:(1) Varieties of fish in the ponds(2) Types of ponds(3) Feed ingredients being used in

the farm(4) Find out what the production

capacity of the farm is

15.2.4 BEE-KEEPINGHoney is widely used and therefore bee-keeping for making honey has become anagricultural enterprise. Since bee-keepingneeds low investments, farmers use it as anadditional income generating activity. Inaddition to honey, the beehives are a sourceof wax which is used in various medicinalpreparations.

The local varieties of bees used forcommercial honey production are Apis ceranaindica, commonly known as the Indian bee,A. dorsata, the rock bee and A. florae, thelittle bee. An Italian bee variety, A. mellifera,has also been brought in to increase yield ofhoney. This is the variety commonly used forcommercial honey production.

The Italian bees have high honey collectioncapacity. They sting somewhat less. They stayin a given beehive for long periods, and breedvery well. For commercial honey production,bee farms or apiaries are established.

The value or quality of honey dependsupon the pasturage, or the flowers availableto the bees for nectar and pollen collection.In addition to adequate quantity of pasturage,the kind of flowers available will determinethe taste of the honey.

uestions1. What are the desirable

characters of bee varietiessuitable for honey production?

2. What is pasturage and how is itrelated to honey production?

Q(a) (b)

Fig. 15.7: (a) Arrangement of beehive in an apiary(b) honey extractor

QWhatyou havelearnt There are thirteen nutrients essential for crops. Of these, six

are required in large quantities and are known as macro-nutrients whereas seven nutrients are required in smallquantities and are known as micro-nutrients.

Manure and fertilizers are the main sources of nutrient supplyto crops.

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Organic farming is a farming system with minimal or nouse of chemicals as fertilizers, herbicides, pesticides etc.and with a maximum input of organic manures, recyledfarm wastes, and bio-agents, with healthy cropping systems.

Mixed farming is a system of farming on a particular farmwhich includes crop production, raising of livestock etc.

Mixed cropping is growing of two or more crops simultaneouslyon the same piece of land.

Growing two or more crops in definite row patterns is knownas inter-cropping.

The growing of different crops on a piece of land in pre-plannedsuccession is called crop rotation.

Varietal improvement is required for higher yield, good quality,biotic and abiotic resistance, shortening the maturity duration,wider adaptability and desirable agronomic characteristics.

Farm animals require proper care and management such asshelter, feeding, breeding and disease control. This is calledanimal husbandry.

Poultry farming is done to raise domestic fowls. Poultryproduction includes egg production and broiler production forpoultry meat.

To enhance poultry production, cross breeding is done betweenIndian and exotic breeds for variety improvement.

Fish may be obtained from marine resources as well as inlandresources.

To increase production of fish, they can be cultured in marineand inland ecosystems.

Marine fish capture is done by fishing nets guided by echo-sounders and satellites.

Composite fish culture system is commonly used for fishfarming.

Bee-keeping is done to get honey and wax.

Exercises1. Explain any one method of crop production which ensures

high yield.

2. Why are manure and fertilizers used in fields?

3. What are the advantages of inter-cropping and crop rotation?

4. What is genetic manipulation? How is it useful in agriculturalpractices?

IMPROVEMENT IN FOOD RESOURCES 215

5. How do storage grain losses occur?

6. How do good animal husbandry practices benefit farmers?

7. What are the benefits of cattle farming?

8. For increasing production, what is common in poultry, fisheriesand bee-keeping?

9. How do you differentiate between capture fishing, maricultureand aquaculture?