Vegetable Crops –PLSC 451/55 Lecture 13, Taro, Yam Instructor: Dr. Stephen L. Love Aberdeen R & E Center 1693 S 2700 W Aberdeen, ID 83210 Phone: 397-4181 Fax: 397-4311 Email: slove@uidaho.edu

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

Taro Propagation 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 Countries China 1,320 mt Nigeria 1,300 Ghana 1,240 Japan 330 Papua 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

SE Asia Dioscorea alata (Greater yam) – most widely distributed

Africa Dioscorea rotunda (Yellow yam) – greatest production

China Dioscorea batatas (Chinese yam)

China Dioscorea batatas (Chinese yam)

SE Asia Dioscorea esculenta (Lesser yam)

Africa Dioscorea bulbifera (Aerial yam)

Tropical America Dioscorea trifida (Cush-cush yam)

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 market African peanut and yam soup Consumer use Fresh market Baked, boiled, pounded, fried, dried and ground into flour (Some types must be heavily processed -boiled, pounded and leached - to eliminate alkaloids)

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 season Vines 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

Vanatu vine jumpers Influence on local culture Celebration of harvest, rites to invoke success of a new crop year

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 climates Name 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 weedy Harvested by hand or machine Careful handling necessary if stored Store at 32-36 degrees Can be stored for several months

Jerusalem artichoke field