The year was 1993 when the groundnut variety Tissa, a product of mutation breeding, was released in Sri Lanka. As far as plant breeding is concerned, 25-year-old varieties are often ancient history – part of the past. Usually, new varieties are well received when they are released but as plant breeders continue to develop new improved varieties to meet new needs, the farming community also moves on. However, for the 1993 Tissa groundnut, it’s a different story. It remains by far the most popular groundnut variety among Sri Lankan farmers, who chose it for 80 percent of their groundnut plantings, consider it a cash crop and have seen their groundnut income increase 5 percent. Sri Lanka started its mutation breeding programme in the late 1960s with the help of the Joint FAO/IAEA Division that has continued to provide equipment and training. To breeders, Tissa was such a success that they now use it to breed new and even better groundnut varieties.
In Sri Lanka, where agriculture is the most important sector of the economy, nearly 82 percent of the population lives in rural areas and agriculture accounts for 30 percent of national employment. Although rice is by far the major crop for the country, about 5 percent of the farm families in Sri Lanka earn extra income growing and selling groundnuts. While not a main ingredient of Sri Lankan cuisine, groundnuts are often found in curries and fried rice, or roasted to be eaten as snacks. Farmers also benefit from a trend towards production of value-added groundnut products in the confection and snack industries, while still taking advantage of their traditional markets which include selling their groundnuts as an oil crop and as animal feed.
For the past 25 years, farmers in Sri Lanka have overwhelmingly chosen Tissa, a groundnut variety developed in the 1990s through irradiation of a Viet Nam groundnut. One element of this success undoubtedly stems from a survey that the breeders performed to determine what characteristics groundnut farmers and consumers would want from an improved groundnut variety. Based on input from farmers, they selected for disease resistant, drought tolerant and high-yield lines, and with the Tissa variety, they also selected a lower shell ratio and a 40 percent oil content. Tissa also has a short growing season, which means that it can be planted as an extra crop, often between rice seasons, with minimal land preparation and few inputs.
