1. Vegetable Crops –PLSC 451/55 Lecture 13, Taro, Yam
Instructor:
Dr. Stephen L. Love
Aberdeen R & E Center
1693 S 2700 W
Aberdeen, ID
Phone: Fax:

3. Taro field

4. L to R: taro, yam, sweet potato, cassava

5. Taro
Also Known As:
Dasheen
Cocoyam
Kolocasi
Ocumo
Dalo

6. Taro plant (Dasheen)

7. Taro Domestication Probably originated in India or Southeast Asia
Taken to China and Japan AD
Spread to Africa and South Pacific AD
Came to the Western Hemisphere with slaves

9. 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

10. Taro plant

11. Taro corm

12. Taro Production – Climate and soils Tropical Warm-season, very tender
Tolerates heavy, clay soils
Needs abundant water
Can withstand waterlogged soils
Optimal pH
Tolerates salty water, quick storm recovery

13. Taro Production Systems Very few large producers
(Partially mechanized)
Virtually no organic production
Most production on subsistence and small market farms

14. Taro Production System - Dryland Not ponded
Irrigated or planted in the dry season
Often intercropped in subsistence production
Herbicides commonly employed for weed control

15. Taro Production System - Wetland Ponded or flooded
Requires cheap, surplus water
Monoculture
Herbicides not required

16. Taro Propagation Often propagated from a “huli”
Propagules commercially unavailable
Nurseries co-produced
Hand-planted or machine assisted

17. Taro Harvest Maturity indicated by leaf drop and yellowing
Harvest usually by hand
No post-harvest curing necessary
Store at degrees
Can be stored for 18 weeks, 2 day shelf-life

18. Harvested taro, ready for market

19. Major Producing Countries
China 1,320 mt
Nigeria 1,300
Ghana 1,240
Japan
Papua New Guinea
Considered to be a staple crop in Africa

20. Taro Consumer use Fresh market Boiled or baked Processed
Chips, canned, frozen, dehydrated flour used for noodles, cakes and baby food

21. Making poi by mashing taro root

22. Poi made from taro root

23. Taro boiled with fish

24. Boiled taro in coconut milk

25. Thai desert made from taro, beans, and egg yolks

26. Taro Taxonomy Monocotyledon Family: Araceae
Genus and species: Colocasia esculenta
Related species: calamus, Jack-in-the-pulpit

28. Yam (D. batatas)

29. Yam plant

30. Yam tubers

31. Yam Taxonomy Monocotyledon Family: Dioscoraceae
Genus and species: Dioscorea (species)
Related species: 250 species of wild yams

32. 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

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

34. Africa
Dioscorea rotunda (Yellow yam) – greatest production

35. China
Dioscorea batatas (Chinese yam)

36. China
Dioscorea batatas (Chinese yam)

37. SE Asia
Dioscorea esculenta
(Lesser yam)

38. Africa
Dioscorea bulbifera (Aerial yam)

39. Tropical America
Dioscorea trifida (Cush-cush yam)

40. Major Producing Countries
Nigeria 27 mil mt
Ghana 4
Ivory Coast 3
Benin 2
Togo
Colombia

41. 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

42. 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

43. 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)

44. 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

45. 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

46. Yam
Production
Propagated using “head” of tubers from the previous crop
Six mo to 2 yr growing season
Vines are staked and trained

47. 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

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

49. Yam
Production – Diseases and Pests
Has very few natural pests

50. Yam Production – Harvest and storage Mostly hand harvested
Stored at degrees
Chilling injury at <50 degrees
Ventilation essential
Stored for 6-8 months (ambient)

51. Yam storage

53. Jerusalem artichoke flower

54. Jerusalem artichoke tubers

55. 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)

56. 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

57. Jerusalem Artichoke Production Production in specialty market gardens
Planted using tuber pieces
Planted in fall or very early spring
Relative easy to grow

58. Jerusalem Artichoke Production - Misc. Volunteers become weedy
Harvested by hand or machine
Careful handling necessary if stored
Store at degrees
Can be stored for several months

59. Jerusalem artichoke field