The following is extracted from the BGRI Newsletter Special Edition, 3rd April 2015:
Kenyan Variety Robin Overcome by Two New Ug99 Variants
A popular wheat cultivar, Robin, sustained severe damage in some farmers’ fields by stem rust in the 2014 crop season in Kenya. Robin became popular because of high yield potential and resistance to previously known Ug99 races. The resistance was conferred by stem rust gene SrTmp, which was effective to the previous races of the Ug99 race group. KALRO scientists collected several samples from various field sites, including the stem rust resistance screening nurseries at Njoro, and race analyses conducted by CDL and GRRC identified two new variants in the Ug99 race group, both of which were virulent to SrTmp. One of the two new variants was also detected in the 2014 samples from neighboring countries. The detection of these new races is a result of worldwide efforts in recent years on stem rust surveillance to detect and monitor Ug99 and other significant races that pose a continuous threat to wheat production. During the past years KALRO has released several stem rust resistant wheat varieties and others are at advanced stages of testing in national variety registration trials. Varieties such as ‘Kingbird’, ‘Kenya Tai’, ‘Eagle 10’, ‘Kenya Sunbird’ and ‘Kenya Hawk 10’ continue to be resistant to the new SrTmp virulent variants.