Adoption estimates of improved cassava varieties in nine countries in South and Southeast Asia indicate that 2.7 million hectares are grown using CIAT-related varieties

STORY FOR COMMUNICATION USE

The International Center for Tropical Agriculture (CIAT) collaborated with research and development partners in nine countries in South and Southeast Asia to document the adoption of different cassava varieties. These efforts were part of the broader initiative funded by the Standing Panel of Impact Assessment of the CGIAR (SPIA) and Michigan State University. Cassava experts from Vietnam, Thailand, Cambodia, Laos, Myanmar, The Philippines, Indonesia, China and India got together in country workshops to discuss the use of different cassava varieties and estimated the adoption of these varieties at major production zones and national levels. A follow-up study in Vietnam used DNA fingerprinting on a representative household survey to confirm the extent of adoption of improved cassava varieties.

Adoption estimates indicate that cassava production in the studied countries is dominated by improved cassava varieties that cover 82.7% of the total cassava production areas (4.1 million hectares). The acreage cultivated with local varieties or land races only reaches 17.3% of the total area. Since 1975, CIAT has participated in most of the development of cassava varieties released in Asia and 2.7 million hectares (65% of the area with improved material) is planted with CIAT related cassava varieties. There is however a large variability in terms of adoption of improved cassava varieties across countries. The study in Vietnam found 85 different improved varieties being extensively used in over 90% of production areas, with the remaining acreage being covered by landrace varieties and provided more accurate results on varietal distribution.

In countries were cassava is mainly targeted to satisfy the growing demand of cassava starch and other industrial purposes, the use of improved varieties reached almost 100% of the total cassava acreage. The efforts made by CIAT and its partners are providing evidence of the large payoffs that cassava genetic improvement can provide. The DNA fingerprinting adoption study in Vietnam evidenced large returns on breeding investments with specific varieties. The highest adoption rates were achieved by varieties KM419 that covered 38.73% of the total cassava production acreage and KM94 that covered 31.6%. Other varieties developed by regional breeding programs are also generating large returns to investment.

ELABORATION OF IMPACT STATEMENT

Since 1975, CIAT established long-term collaborations with many cassava breeding programs in Asia and  contributed in the development of improved cassava varieties. At the beginning a large number of cassava researchers from many Asian countries were trained in CIAT headquarters in Cali, Colombia. But since 1983, with the establishment of CIAT regional office in Bangkok, CIAT was able to establish a closer and more productive collaboration with the Thai and other national cassava programs.

The Thai cassava program was the main beneficiary of the collaboration of CIAT in the region, CIAT had a role to facilitate the access to the Latin-American collection of cassava accessions that together with the Thai collection and other regional collections increased the genetic variability needed to establish the regional breeding program. The cassava genetic improvement program started to focus on breeding for high yielding and high starch content, responding to the raising demand coming from the cassava indus try.

The breeding efforts resulted in a large number of advance material that has been broadly tested and that resulted in the release of many of today’s very well use cassava varieties. Thus Rayong 60 was released in 1987, Rayong 90 in 1991, well the well-known Kasetsar 50 (KU-50) was released in 1992. Later other varieties, like Rayong 5 (1994) and Rayong 72 (1999) became available to Thai cassava growers. Due to the success on the uptake of this varieties and their impact on cassava yields and starch yields, all these varieties where disseminated rapidly into neighboring countries.

In addition of becoming the center of distribution of highly demanded varieties in the southeast region, many of these Thai bred varieties became part of the breeding programs in many other countries in the region and have originated new and productive varieties that are available for cassava growers in many regions. The most recent cases could consider the varieties Huay Bong 60 and Huay Bong 80 in Thailand, and the varieties KM 140, KM 98-5 and KM 419 in Vietnam.

Currently, 2.7 million hectares are reported to be planted with CIAT-related material across the nine countries, with large variability in adoption of improved cassava varieties between countries.  In Vietnam for example, the study on DNA fingerprinting found 85 different improved varieties being extensively used in over 90% of production areas, with the rest using landrace varieties.