Varieties of Sweet Potatoes

1. Introduction

Sweet potato is a root crop which originated in Central America but is now grown in many countries. Most of the world production is concentrated in 15 countries which account for almost 97% of total world output (Scott, 1992). China is the world's largest producer of sweet potato with 105 million tons in 1993, representing about 80% of total world production. A rapid growth in population during the 1980s, resulting in severe pressure on farmland, is considered to be a prime factor for the rapid expansion of production in many countries, in particular in Vietnam, Kenya, Rwanda, Burundi, North Korea and Madacasgar. The largest producers in Africa are: Uganda (1.9 million tons), Rwanda (0.7 million tons), Burundi (0.68 million tons) and Kenya (0.63 million tons).

2. Sweet potato varieties

From 1968, seven varieties of sweet potatoes have been introduced in Rwanda. Those varieties are Nyirakayenzi, Rukocoka, Gahungezi, Nyiramujuna, Nsulira, Kigingo na Bukarasa. Later on, other varieties were also introduced: Mugande, Wadada, Karebe,Rusenya, Nsasagatebo, K 51/3261, TIS 2544, Turatugure, na Rutambira. Recently, improved varieties which are rich in Beta carotene have been introduced by the research and are widely disseminated: Ndamirabana, Terimbere, Giramata, Ukerewe, Kabode, Vita, Cacearpedo na Gihingumukungu. Some of these varieties have been introduced from the neighboring countries such as Tanzania, Kenya and Uganda, tried for adaptability in many locations and they were proved to be adapted to the Rwandan conditions..