Drought-tolerant Crops to Contribute to Food Security in Namibia


Farmers in Namibia now have new crop varieties of cowpea and sorghum that are more tolerant to drought and pests planted this year, thanks to nuclear technology provided with the support of the IAEA and the Food and Agriculture Organization of the United Nations (FAO). 

Namibia’s Ministry of Agriculture, Water and Forestry, through an IAEA technical cooperation project which began in 2009, has enhanced existing seed varieties of cowpea and sorghum in its first ever plant breeding programme, released the new varieties in 2018 and facilitated seed multiplication for the 2019 cropping season.

“The achievement in improved crop varieties and quality plays an important role in the production of food and hence ensuring food security,” said Johanna Andowa, Director of Research at the Ministry. “Initially, we only had one sorghum variety and three cowpea varieties, and now with the newly released four sorghum and seven cowpea varieties, farmers have more options to choose from. These varieties are contributing to the national goal of producing high-yielding crops with better tolerance to physical and biological stresses, as well as improved nutritional quality.”

Traditional seed varieties no longer meet the needs of close to 700,000 agricultural households in northern Namibia, where drought and poor soil inhibit crop productivity, Andowa said. “Farmers have reported yield losses and the resulting decrease in productivity is contributing to food insecurity, malnutrition and even famine.”

In response, the IAEA and the FAO have supported Namibia through the transfer of technology and helped to build capabilities in plant breeding and soil and water management.

The new varieties are expected to benefit over 8,000 farmers in the first season, and more farmers will be able to get involved as the seed production increases, Andowa said.

The enhanced cowpea varieties produce higher yields during a shorter growing period, explained Lydia Ndinelao Horn, researcher at the University of Namibia: “They start flowering after 30 days and are fully mature after about two and a half months, while traditional varieties need 60 days just to start flowering.”

Horn highlighted that the new sorghum varieties also have higher yields, as well as increased resistance to the ergot fungus, to which the traditional varieties are susceptible, and which affects yields, also possibly causing serious poisoning if consumed by humans or animals.

To generate the initial batch of seeds, scientists at the Joint FAO-IAEA laboratories in Seibersdorf, Austria, used gamma irradiation on the local seed varieties to induce desired changes in the plants’ DNA. By using radiation to mimic the natural process of spontaneous mutation, scientists can generate varieties with new and useful traits. (see The Science box).

The treated seeds were then shipped back to Namibia, where three crop research stations were involved in the development and examination of new mutant lines for drought and pest tolerance. Farmers then selected best lines during a field trial. As part of this cooperation, the first ever qualified Namibian plant breeder and five plant breeding laboratory technicians were also trained.

In 2018, the improved varieties were given to seed growers for further multiplication, to produce enough seeds for commercial spread. The seeds are currently planted.