Salinity-tolerant rice variety set to boost rice yield in stress prone areas in Kenya

Millions of hectares of land suited to rice production in Asia and Africa are not currently used because of their high salt content. Extremely high salt stress circumstances cause the plant to die, while moderate to low salt stress conditions impact the plant growth rate. This presents a challenge to ensuring food sustainability while facing the impact of climate change, such as in the case of coastal and northeastern regions in Kenya where sodic soil with high levels of sodium is widely distributed.

The International Rice Research Institute (IRRI) in collaboration with the Kenya Agricultural and Livestock Research Organization (KALRO) launched the CSR 36, a salinity-tolerant and high-yielding variety for cultivation in both irrigated and rainfed areas on 18 January in Kiarukungu village in the Hola irrigation scheme, Tana-River County. This new variety is being offered to Kenyan farmers along with other recently-released high-yielding and climate-resilient rice varieties in the country such as 08FAN10 (Mkombozi) and IR05N221 (Komboka) also co-developed by IRRI and KALRO.

During the Field Day in Hola, 47 key rice value chain stakeholders  and policymakers including local and national government officials, National Irrigation Authority (NIA), and the Rice Promotion Program (RIPP) representatives and 84 farmers (39 of whom are women) attended to witness the launch of CSR 36.

Results from on-farm validation trials across multiple sites in Kenya showed that CSR 36 could yield up to 5.5–6.0 tons per hectare under sodic soil conditions. This includes high soil pH levels of up to 9.8 and electrical conductivities of 6–10 dS/m, and about 6 tons per hectare in non-saline soils with an ideal pH range of 5.5–6.6. In contrast, Basmati 370, a popular local variety, only yields 2.4 – 3.8 tons per hectare under similar stressful environments. These findings show that the variety is tolerant to these sodic soil conditions. Other than its salinity tolerance, CSR 36 is also medium-maturing, aromatic, has long and thin grains, softens when cooked, is non-sticky, and has ratooning ability. These characteristics closely reflect the preferences of farmers and consumers as determined by the national product concepts which was developed in consultation with the national agricultural research and extension systems (NARES) and IRRI. Hence, it is anticipated that if demonstrated and positioned well, the variety will be extensively grown in the nation. This follows a similar adoption trend in Komboka, where  there was a significant growth in the variety's area of cultivation from roughly 40 to 4,435 acres across the country from 2019-2021.

Dr. Ajay Panchbhai, Regional Breeding and Seed Systems Lead for Africa expressed that Kenya continues to import millions of tons of rice to meet the local consumption whereas its potential for rice production is enormous. ″I recognized the huge amount of time and resources that go into the development of any new variety; thus if the new varieties meet the market demands, I strongly urge farmers to adopt the new, climate-resilient, and high-yielding varieties that IRRI and its collaborators in the region released,"  said Dr. Panchbhai. Participants were also encouraged to use good-quality seeds, fertilizers and other good agronomic practices in combination with the new climate-resilient varieties to maximize their productivity. IRRI is currently supporting local partners in the country, including the NARES, non-governmental organizations, farmers’ cooperatives, and women groups to ensure quality seeds of the new varieties are available as part of an ongoing Accelerated Genetic Gain in Rice (AGGRi)  Alliance initiative funded by the Bill and Melinda Gates Foundation (BMGF). Commenced in 2019, AGGRi Alliance has made a significant contribution in unifying and modernizing rice breeding and seed systems efforts in South Asia and Sub-Saharan Africa. The efforts of strengthening rice seed systems in East and Southern Africa are also aptly complimented through OneCGIAR Seed Equal initiative.

On behalf of KALRO’s  Director General, Dr. Eliud Kireger,  Mr. Finyange Pole, who is the Director Industrial Crops Research Institute, emphasized among the participants the need to embrace new technologies, particularly new high-yielding, climate-resilient rice varieties to strengthen the rice sector in Kenya.

Currently, there are only about 5,000 acres under rice cultivation in the two irrigation schemes; this is partly attributed to a lack of suitable varieties adapted to the soil conditions in the area. The launch of CSR 36 is expected to contribute to the expansion of rice cultivation area particularly in the Bura and Hola irrigation schemes, which have a combined area of 24,000 acres and are largely characterized by sodic soils.

Other irrigation schemes such as Rahole in Garissa, Kimorigho, and Kitobo in Taita-Taveta counties, which are also affected by soil salinity could also benefit from these salinity-tolerant varieties.