Imperial Valley conditions limit Karnal bunt in wheat

Abstract

The amount of disease occurring in any given area depends on the presence of the pathogen in sufficient abundance, susceptible hosts and favorable climatic conditions. Each of these factors were severely limiting to the establishment of Karnal bunt (KB) in the Imperial Valley during the 1996 growing season, and none of the 1,476 fields (106,592 acres) tested was shown to be infected with KB. Karnal bunt does not appear to be a threat to wheat production in the Imperial Valley because desert conditions are unfavorable for its development. However, this does not rule out the possibility that low levels of disease may occur occasionally. Assuming that current growing conditions continue and that KB-free seed is planted, the Imperial Valley is at low risk for a KB outbreak.