Two scientists with a long history of collaboration with CIAT have been honored for contributions towards the world’s most widely grown cassava variety – now grown by 60 to 75 percent of all cassava farmers in Thailand and Vietnam – and a key food security crop and source of income throughout Southeast Asia.
At the week-long World Congress on Root and Tuber Crops in Nanning, China this week, Dr. Chareinsuk Rojanaridpiched, formerly of Kasetsart University in Thailand, and CIAT emeritus Dr. Reinhardt Howeler, a soil scientist with more than 20 years of experience in Asia, received the Golden Cassava Award.
Dr. Chareinsuk Rojanaridpiched recived the award for developing the cassava variety Kasetsart 50 (KU 50), cultivated on more than 1 million hectares in Thailand and Vietnam, as well as in large areas of Indonesia, Cambodia, the Philippines and Lao PDR.
Dr. Reinhardt Howeler was recognized for his contributions towards improving soil management practices. He worked directly with farmers throughout the region to ensure widespread adoption of new varieties including KU 50, as well as better crop and soil management, leading to higher yields and farm income.
“I have been very lucky to have worked with researchers and extension workers and farmers who worked hard to adopt new varieties and improved practices, resulting in higher yields and considerable improvements in farmers’ livelihoods,” said Dr. Reinhardt.
The story of cassava in Asia, from root to riches
Cassava (Manihot esculenta) is a carbohydrate source for more than 500 million people globally. It ranks sixth among crops for calorific contribution and is produced as a staple crop in Africa, Asia and South America – accounting for 53%, 33% and 14% of global production, respectively.
Today in Southeast Asia, the crop supports an estimated 40 million mostly poor farmers with less than five hectares. The crop tolerates stress, drought, heat, and can grow in poor soil in marginal upland environments with minimal investment.
During the 1990s, cassava production stagnated largely due to a downward spiral in demand in European animal feed markets for cassava chips and pellets. Cassava yields also stagnated or declined, and attempts to improve local varieties were not successful as a result of lacking cassava genetic diversity in Asia.
Despite the fact that cassava is a vital source of calories and food security in Southeast Asia, especially among poor ethnic minorities, many researchers neglected cassava improvement in favor of other staples such as rice and maize.
Yet, Dr. Chareinsuk Rojanaridpiched and colleagues at Kasetsart University and the Department of Agriculture in Thailand, persevered to develop the highly successful cassava variety KU 50, released in 1992. They used a very well adapted local Thai cassava variety, crossed with one with a genetic background from CIAT’s genebank in Colombia – the largest cassava germplasm collection in the world – to achieve this, drawing on local breeding expertise.
Tapping this diversity of germplasm in Latin America, the researchers evaluated, made many crosses and exchanged germplasm with CIAT’s genebank, where a total of 6,592 accessions from 28 countries, including 883 genotypes of wild species, are conserved using in vitro techniques.
They improved varieties with potential to meet demands in Asia: higher fresh root yields and starch content; improved disease resistance and environmental adaptability. By 2002, Asian breeders had released more than 50 improved varieties including KU 50 in nine countries, with considerable benefits for cassava growers, almost doubling fresh root yields.
In parallel, Dr. Reinhardt Howeler worked with researchers, extension agents and farmers in China, Vietnam, Indonesia, Thailand, Cambodia, Lao PDR and East Timor, to improve soil fertility management and erosion control practices for cassava and enhance the adoption by farmers of improved varieties.
This involved conducting simple trials with farmers in their fields, with local researchers and extension workers, to select and manage practices for their own conditions. Thousands of farmers learned about new, more efficient practices of cultivating cassava through participation in field days, training courses and cross visits, as well as from brochures, and from radio and television interviews.
The work led to widespread adoption of improved varieties and new soil and crop management practices, contributing significantly to rapid yield increases in Asia in the last 15 years. Estimated increases in annual gross income of cassava farmers in Asia due to higher cassava yields in 2009, compared to 1994, were estimated at more than US$1.75 billion.
Asia is today’s leading cassava trader
Thailand and Vietnam are now the world’s leading cassava exporters, with Thailand and Indonesia the region’s biggest producers. With rapid population growth and urban expansion, use of cassava also extends into niche markets, for example in low fat and gluten-free products – a huge opportunity for smallholder farmers, who supply most cassava.
It’s estimated that income accumulated by cassava growers in Thailand from KU 50, between 1993 and 2011, totaled US$1.56 billion dollars. The national economic benefits of investment in cassava production and export continue to improve. In Vietnam alone, cassava currently fetches between 1.3-1.5 billion US$ annually in exports.
Today, 48 CIAT-related cassava varieties in national breeding programs are planted on more than 40 percent of the region’s total cassava-growing area. According to 2015 estimates, the adoption of improved varieties resulting from research involving CIAT and national partners has reached nearly 100% in Thailand and over 90% in Vietnam.