Lecture 7 - Cassava, Sweet Potato, Yam Flashcards
Other names for cassava
tapioca, manioc, mandioca, yuca
cassava is the _____ source of calories after rice, sugar, and maize
4th
what is cassava mainly used for
food
cassava scientific name
manihot esculenta
cassava ploidy
2n=2x=36
what is the cassava plant
dicotyledonous short-lived perennial tuberous shrub grown as an annual or biennial
cassava plant height
1-5 m
Africa produces ___ of the world’s cassava
1/2
where was cassava domesticated
tropical brazil
adaptation of cassava to tropics
17-20C no freezes
1000 to 1500mm rainfall
tolerant of drought
how is cassava propagated
by stem cuttings with at least 3 nodes
how is cassava harvested
by hand or tractors where the roots are pulled out of the ground
how is cassava prepared
cooked boils, roasted, fried, or sundried. Must be detoxified by soaking/boiling
Biofortified yellow cassava
high pro-vitamin A
What institute produces yellow cassava
the international institute of tropical agriculture in Ibadan, Nigeria
Sweet potato scientific name
Ipomoea batatas Convolvulaceae
sweet potato ploidy
2n=6x=90 polyploid
does sweet potato self cross
no, it outcrosses
how to tell the difference between yam and sweet potato
yam = dry, starchy flesh that looks like bark
sweet potato = moist flesh with smooth skin
sweet potato is a ______ crop
root
difference between root crop and tuber crop
root crop = structure of typical roots with no nodes, internodes, or buds
tuber crop = modified stem that thickens for storage that includes nodes and internodes
how can sweet potato vary
vary in skin and flesh colour, tastes, and textures
sweet potato is the _____ most important food crop
7th
different uses of sweet potato
food, industrial (dye, starch), and animal feed
benefit of growing sweet potato
income for farmers
multiple food sources (root, vine, leaves)
nutrition of sweet potato
nigh nutrition in vitamin A, C, E, B, iron, zinc, potassium, fiber
Subsistence Production
used as an element in intercropping
what climate does sweet potato prefer
warm 23-32C (susceptible to chilling)
Sandy, light soils
2 methods of propagating sweet potato
- propagated from previous crop using cuttings
- rooted slips from sprouted roots
how is sweet potato harvested
hand harvested
how is sweet potato stored
cure at 27-30C degrees, store at 12 degrees and with good air flow
important pests and diseases of sweet potato
sweet potato weevil
black rot
sweet potato virus
how to control sweet potato weevil
deep hilling
deep rooted varieties
timing harvest
where was yam domesticated
SE Asia, Japan, Africa, and tropical America with different species
yam species domesticated in china
Dioscorea batatas (chinese yam)
yam species domesticated in SE Asia
Dioscorea esculenta and D. alata
yam species domesticated in Africa
Dioscorea bulbifera and D. rotunda
yam species domesticated in tropical america
Dioscorea trifida (cush-cush yam)
What is yam a staple crop in
Africa
what is yam high in
starch
how is yam propagated
using head of tubers from previous crop
how is yam harvested
hand harvested
yam had ______ natural pests
few
