Abstract only

Over the last decade wheat has become an important food crop in Kenya with demand increasing to 6% annually; however, the annual production increases have remained below 1% leading to imports of 0.6 million tonnes each year. The slow growth could be attributed to a number of constraints such as drought, diseases and changed land use. Stem rust and yellow rust are rated as the most important biotic constraints in Kenya, and Kenyan wheat farmers have been fighting the Ug99 race group of the stem rust fungus since 2001. KARI, together with CIMMYT and other institutions, accepted the challenge, joined BGRI and established the critical screening facility at Njoro where over 300,000 wheat accessions from more than 20 countries/institutions were introduced and evaluated since 2005. The initial attempt in Kenya to address the challenge posed by Ug99 through deployment of effective race specific genes was not successful as the deployed gene Sr24 was defeated by a variant of Ug99 that caused widespread losses. The introduction of adult plant resistance (APR), largely based on the ?Sr2-complex? present in some of the CIMMYT and old Kenyan varieties, into breeding materials has resulted in a few adapted wheat lines which resist Ug99 in the Kenyan environment. The first Ug99 resistant varieties, Robin and Eagle 10, were released in 2009, and since then six more resistant varieties were released for commercial production with diverse combinations of race-specific and APR genes. Seed was multiplied and supplied to farmers through seed companies and individual farmers, and seed multiplication of new varieties is currently underway. In the future, breeding for rust resistance will focus on combining both major and minor genes for maximum protection and durability. The use of molecular markers to increase efficiency will aid selection of complex resistances. KARI is collaborating with CIMMYT and the National Institute of Agricultural Botany (NIAB) in a BBSRC funed project to improve molecular laboratory facilities in Kenya so as to implement marker assisted breeding strategies. Training courses organized at KARI every year under the DRRW project are designed to train wheat breeders from the public and private sectors n Africa, the Middle East and Central and South Asia, who wish to learn about stem rust, valuation of germplasm, and standardization of note taking, as well as to update themselves h the global knowledge and innovative techniques that can enhance progress and efficiency in their breeding activities. The interaction of Kenyan scientists with the international wheat research community has increased our capacity to handle the wheat rust problem by facilitating testing and rapid release of Ug99 resistant varieties not only in Kenya but also in different wheat growing regions of the world.

Global Wheat Program

English

Lucia Segura

INT0610

CIMMYT Staff Publications Collection