Root and Tuber Crops in the Tropics Cassava

Root and Tuber Crops in the Tropics Cassava Cocoyam Potato Sweet Potato Taro Yam

Definitions z Root (cassava, sweet potato) y. No leaves or reproductive organs z Tuber (potato, yams) y. Fleshy underground stem y. Minute scale leaves with buds (eyes) z Corm (aroids, cocoyam and taro) y. Short, bulblike underground upright stem y. With scale leaves Tropical Horticulture - Texas A&M University

World Production of Root and Tuber Crops (106 mt) FAOSTAT, 2003 About half of the potato production is in the temperate zone Tropical Horticulture - Texas A&M University

Food Utilization of Root and Tuber Crops (1996 data) Tropical Horticulture - Texas A&M University

Feed Utilization of Root and Tuber Crops (1996 data) Tropical Horticulture - Texas A&M University

Origins of Major Root and Tuber Crops Yam Cocoyam Sweet Potato Cassava Taro Potato Tropical Horticulture - Texas A&M University

Cassava - Manihot esculenta Yuca, Mandioca, Tapioca z Plant y. Slender shrub, 5 m y. Enlarged roots x. Sweet to bitter x. White to yellow y. Palmate leaves z Propagation y. Stem cuttings Tropical Horticulture - Texas A&M University

Cassava - Manihot esculenta z Origin y. South America z Distribution y. Tropics and subtropics z Staple food in many tropical regions y. Excellent carbohydrate source Tropical Horticulture - Texas A&M University

Cocoyam - Xanthosoma sagittifolium Malanga, Tannia, Elephant’s Ear z Plant y. Perennial herb y. Corms and cormels z Propagation y. Harvest same plant multiple times y. Portions of central corm Tropical Horticulture - Texas A&M University

Cocoyam - Xanthosoma sagittifolium Malanga, Tannia, Elephant’s Ear z Origin y. West Indies and northern S. America z Distribution y. Tropical regions y. Common in Indonesia z Adaptation y. Lowland tropics Tropical Horticulture - Texas A&M University

Potato - Solanum tuberosum z Plant y. Herbaceous y. Subterannean stems y. Leaves z Propagation y. Eyes from tubers z Important staple crop Tropical Horticulture - Texas A&M University

Potato - Solanum tuberosum z Origin y. Highlands of South America z Distribution y. Widely cultivated from highland tropics to temperate zones z Adaptation y. Cool climate adaptation Tropical Horticulture - Texas A&M University

Sweet potato - Ipomoea batatas z Plant y. Creeping herb y. Enlarged roots vary in shape and color y. Leaves variable in size, shape, color z Propagation y. Young stem cuttings z Important carbohydrate source Tropical Horticulture - Texas A&M University

Sweet potato - Ipomoea batatas z Origin y. Central America z Distribution y. Widely cultivated both in tropics and subtropics z Adaptation y. Tropics to subtropics y. Below 2200 m altitude Tropical Horticulture - Texas A&M University

Taro - Colocasia esculenta z Plant y. Perennial herb y. Subterraneous stem x. Calcium oxalate crystals y. Heart shaped leaves z Propagation y. Suckers y. Corm apices with leaf Tropical Horticulture - Texas A&M University

Taro - Colocasia esculenta z Origin y. Southeast Asia z Distribution y. West Africa y. Caribbean y. Pacific islands z Staple food Tropical Horticulture - Texas A&M University

Yam Dioscorea alata, cayenensis and rotundata (Sixty species cultivated for food and pharmaceuticals) z Plant y. Climbing vine, 10 m y. Tubers vary in shape y. Leaves ovate with cordate base z Propagation y. Tubers z Staple food in arid regions of Africa Tropical Horticulture - Texas A&M University

Yam Dioscorea alata, cayenensis and rotundata (Sixty species cultivated for food and pharmaceuticals) z Origin y. Asia and West Africa z Production y. Mainly Africa z Adaptation y. Lowland tropics y. Drought tolerant Tropical Horticulture - Texas A&M University

Plant Characteristics Tropical Horticulture - Texas A&M University

Plant Adaptation Tropical Horticulture - Texas A&M University

Plant Soil Adaptation Tropical Horticulture - Texas A&M University

Plant Storage Duration Tropical Horticulture - Texas A&M University

Crops compared for Edible Energy Production Tropical Horticulture - Texas A&M University

Crops compared for Edible Protein Production Tropical Horticulture - Texas A&M University

Nutritional aspects of root and tuber crops FW = fresh weight Tropical Horticulture - Texas A&M University

Nutritional Composition of 100 g of Food Tropical Horticulture - Texas A&M University

Importance of Root and Tuber Crops z Important source food and income for the most food insecure households z Why? y. High energy production per ha/day y. Yield better under adverse conditions than other crops Tropical Horticulture - Texas A&M University

Future Trends for Root and Tuber Crops z Increased regional production concentration x. Sub Saharan Africa, 60% cassava production x. West Africa, 90% yam production x. China, 82% of sweet potato production z Increased specialization of End Use x. Increase of processed forms of food x. Increased use of root/tubers for feed and starch derived products z Relative importance remain same y 10. 5% of agricultural value Tropical Horticulture - Texas A&M University

International Research Centers involved with Root and Tuber Crops z CIAT (Colombia) y. Cassava for Americas and Asia z CIP (Peru) y. Potato y. Sweet potato y. Andean roots and tubers z IITA (Nigeria) y. Cassava for Africa y. Yam for Africa Tropical Horticulture - Texas A&M University

International Research Centers involved with Root and Tuber Crops CIAT IITA CIP Tropical Horticulture - Texas A&M University

Any Questions? Tropical Horticulture - Texas A&M University