Abstract
The CIAT cassava program in Colombia has been introducing advanced cassava breeding materials to national cassava breeding programs in the world for the past 20 years and the CIAT Asian cassava program has done the same to national cassava programs in Asia for the past eight years. The total genetic diversity thus transfered may for outweight all the genetic variation previously brought to Asia from Latin America and Africa through traditional means. The primary objective of offering useful breeding materials to national programs is to increase the possibility of producing better cultivars; yet, this often leads to the strengthening of the breeding program per se by working together in the actual breeding process. This scheme has steadily improved the breeding program capacities in Thailand, Indonesia, China, Vietnam, Philippines and Malaysia and the basic yielding capacity of breeding populations has been much enhanced in these countries. Yet, it is in Vietnam where the improvement of the breeding population in terms of yield and root dry matter content took place in a most dramatic manner. Summarizing these evaluation/selection operations, I conclude that national cassava breeding programs are selecting superior genotypes in virtually all the major cassava growing environments in Asia, making good use of CIAT breeding materials. The CIAT/Thai materials are particularly useful especially in the semi-arid lowland and seasonally dry lowland tropics.
