Keywords: Mutation breeding , Indonesia , Soybean , Gamma irradiation
Indonesia’s Ministry of Agriculture last month selected an improved soybean variety developed using nuclear techniques as the basis for its national self-sufficiency plan, which aims to increase food security in the country.
Tempeh, made of fermented soybeans, is a national staple, usually consumed with rice and broth. Due to an increase in population and living standards over the last couple of decades, however, consumption has increased considerably and Indonesia has gradually lost its self-sufficiency in tempeh production. By now it is importing close to 60% of the 2.2 million tons of soybeans consumed each year. As part of its food security plan, the government would like to reverse that trend, and significantly increase domestic production in coming years. That, however, requires a variety suitable for the country’s tropical climate, with high yields and resistance to local pests.
The Ministry of Agriculture has now selected a variety developed by the country’s National Nuclear Energy Agency (BATAN) for mass seed production and distribution among farmers thanks to its favourable traits, said Lukman Hakim, the ministry official in charge of the project. The variety called Mutiara 1 was developed using irradiation, a process often used to generate new and useful traits in crops (see The Science box). The syllable “ra” in its name stands for radiation.
“Farmers prefer variety Mutiara because it is tolerant to flood and submergence, and especially because it has larger seeds than existing varieties,” he said.
The IAEA, in cooperation with the Food and Agriculture Organization of the United Nations (FAO) supports countries, including Indonesia, in the use radiation for agricultural research and development, including the development of enhanced varieties of seeds for improved production.
Higher income for farmers
Mutiara 1 has numerous advantages compared to the traditional soybean variety, said Gatot Gatot, one of 12 farmers in the heart of the country’s soybean growing area in East Java to already use the new variety. “The plants are shorter and stronger, tolerant to wind and resistant to disease,” he said. Even more importantly, the yield – at above 3 tons per hectare – is 25% higher than that of local varieties. The seeds are larger and higher quality, fetching between 6,500 and 7,000 rupiah (40-44 euro cents) per kg, compared to under 6,000 rupiah for the local variety.
“You add up all these advantages, and I am much better off,” Gatot said.
Of the 200 farmers in this village, most would like to plant Mutiara 1, but for now there are not enough seeds to go around, said A. Sidik Tanoyo, an Agriculture Ministry extension officer in the district. “This will now change as a result of the recent government decision.”
In the meantime, BATAN scientists will continue to develop new varieties, further improving their traits. Mutiara 1 does less well during the wet season when its bigger seeds acquire a brownish colour and are less viable, said Azri Kusuma Dewi, a plant breeder at BATAN’s Centre for Isotope and Radiation Application in Jakarta. As a result, it is only recommended for planting in the dry season, with traditional varieties maintained for the other half of the year. “We need to work on further optimizing Mutiara 1 by inducing mutations and breeding another variety for the rainy season,” she said.
THE SCIENCE
Breeding new varieties using nuclear techniques
The Mutiara 1 soybean variety was developed by BATAN scientists through a process known as mutation breeding. Applied since the 1930s to accelerate the process of developing and selecting new valuable agronomic traits, mutation breeding uses a plant’s own genetic make-up, mimicking the natural process of spontaneous mutation. The mutation process generates random genetic variations, resulting in plants with new and useful traits.
BATAN scientists use gamma irradiation to induce mutations in seeds and considerably speed up the natural mutation process. After seed irradiation, they test the new mutant plants for various characteristics, and select those displaying useful traits for further breeding and subsequent distribution to farmers.
