vegetable crops –plsc 451/55 lecture 13, taro, yam instructor: dr. stephen l. love aberdeen r...
TRANSCRIPT
Vegetable Crops –PLSC 451/55 Lecture 13, Taro, Yam
Instructor:Dr. Stephen L. LoveAberdeen R & E Center1693 S 2700 WAberdeen, ID 83210Phone: 397-4181 Fax: 397-4311Email: [email protected]
Taro field
L to R: taro, yam, sweet potato, cassava
Taro
Also Known As:
Dasheen
Cocoyam
Kolocasi
Ocumo
Dalo
Taro plant (Dasheen)
Taro
Domestication
Probably originated in India or Southeast Asia
Taken to China and Japan - 2000 AD
Spread to Africa and South Pacific - 500 AD
Came to the Western Hemisphere with slaves
Yautia (Taro relative)
Domestication
Also called Tannia
Yautia is a related Arum species and is replacing Taro in many African countries
Native of tropical America
Species name: Xanthosoma sagittifolium
Very similar in appearance, culture, use
Taro plant
Taro corm
Taro
Production – Climate and soils
Tropical
Warm-season, very tender
Tolerates heavy, clay soils
Needs abundant water
Can withstand waterlogged soils
Optimal pH 6.0-7.0
Tolerates salty water, quick storm recovery
Taro
Production Systems
Very few large producers
(Partially mechanized)
Virtually no organic production
Most production on subsistence and small market farms
Taro
Production System - Dryland
Not ponded
Irrigated or planted in the dry season
Often intercropped in subsistence production
Herbicides commonly employed for weed control
Taro
Production System - Wetland
Ponded or flooded
Requires cheap, surplus water
Monoculture
Herbicides not required
TaroPropagation
Often propagated from a “huli”
Propagules commercially unavailable
Nurseries co-produced
Hand-planted or machine assisted
Taro
Harvest
Maturity indicated by leaf drop and yellowing
Harvest usually by hand
No post-harvest curing necessary
Store at 45-50 degrees
Can be stored for 18 weeks, 2 day shelf-life
Harvested taro, ready for market
Major Producing CountriesChina 1,320 mtNigeria 1,300Ghana 1,240Japan 330Papua New Guinea 220
Considered to be a staple crop in Africa
Taro
Consumer use
Fresh market
Boiled or baked
Processed
Chips, canned, frozen, dehydrated flour used for noodles, cakes and baby food
Making poi by mashing taro root
Poi made from taro root
Taro boiled with fish
Boiled taro in coconut milk
Thai desert made from taro, beans, and egg yolks
Taro
Taxonomy
Monocotyledon
Family: Araceae
Genus and species: Colocasia esculenta
Related species: calamus, Jack-in-the-pulpit
Yam (D. batatas)
Yam plant
Yam tubers
Yam
Taxonomy
Monocotyledon
Family: Dioscoraceae
Genus and species: Dioscorea (species)
Related species: 250 species of wild yams
Yam
Species used for cultivation
D. alata (greater yam) – SE Asia
D. batatas (Chinese yam) – China
D. rotunda (yellow yam) – Africa
D. esculenta (lesser yam) – SE Asia
D. bulbifera (aerial yam) – Africa
D. trifida (cush-cush) – Tropical America
Dioscorea alata (Greater yam) – most widely distributed
SE Asia
Dioscorea rotunda (Yellow yam) – greatest production
Africa
Dioscorea batatas (Chinese yam)
China
Dioscorea batatas (Chinese yam)
China
Dioscorea esculenta
(Lesser yam)
SE Asia
Dioscorea bulbifera (Aerial yam)
Africa
Dioscorea trifida (Cush-cush yam)
Tropical America
Major Producing Countries
Nigeria 27 mil mt
Ghana 4
Ivory Coast 3
Benin 2
Togo 0.5
Colombia 0.3
Yam
Domestication
Used for food in West Africa (probable area of origin) >50,000 years ago
Cultivated 3000 BC in West Africa and SE Asia
Yam
Use and importance
Important staple crop in Africa
Subsistence production systems
Considered to be an under-utilized crop
Very high in starch, protein, minerals
Yam
Consumer use
Fresh marketBaked, boiled, pounded, fried, dried and ground into flour
(Some types must be heavily processed -boiled, pounded and leached - to eliminate alkaloids)
African peanut and yam soup
Yam
Unusual compounds
Dioscorine – alkaloid in D. hispida and other yams, very poisonous (used as a pest poison)
Sapogenin – steroidal alkaloid used in the production of cortisone, progesterone, and other drugs
Yam
Production – Climate and soils
Tropical
Warm-season, very tender
Will not grow in temps <70 degrees
Needs abundant water
Requires a well-drained soil
Yam
Production
Propagated using “head” of tubers from the previous crop
Six mo to 2 yr growing seasonVines are staked and trained
Yam
Production constraints:
Quantity of tubers for seed (30% of production)
Quantity of labor to plant, stake, and harvest
Tubers are deep and harvest difficult
Influence on local culture
Celebration of harvest, rites to invoke success of a new crop year
Vanatu vine jumpers
Yam
Production – Diseases and Pests
Has very few natural pests
Yam
Production – Harvest and storage
Mostly hand harvested
Stored at 55-60 degrees
Chilling injury at <50 degrees
Ventilation essential
Stored for 6-8 months (ambient)
Yam storage
Jerusalem artichoke flower
Jerusalem artichoke tubers
Jerusalem Artichoke
Domestication
Native of North America – found wild in the midwest and northeast
Cultivated by the Indians prior to European migration
Taken to Europe where it is grown in dry climatesName derived from Italian girasole articocco
(sunflower edible)
Jerusalem Artichoke
Use and importance
Similar in appearance and size to Irish potato
Very limited usage
Storage carbohydrate in inulin (polymer of fructose), useful for diabetics
Cooked and eaten in similar manner to potato
Jerusalem Artichoke
Production
Production in specialty market gardens
Planted using tuber pieces
Planted in fall or very early spring
Relative easy to grow
Jerusalem Artichoke
Production - Misc.
Volunteers become weedyHarvested by hand or machineCareful handling necessary if storedStore at 32-36 degreesCan be stored for several months
Jerusalem artichoke field