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
Nigeria
Ghana
Japan
Papua New Guinea
1,320 mt
1,300
1,240
330
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
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