Tolerance to paraquat is correlated with the traits associated with water stress tolerance in segregating F2 populations of barley and wheat

To identify scorable marker traits that can be used in cereal breeding programs for selecting drought tolerant individuals, we investigated the correlation among the drought-associated traits in two F-2 populations derived from the crosses made between drought tolerant and sensitive barley and wheat parental genotypes. The parental genotypes of these crosses also differed by at least three other traits - paraquat tolerance, leaf size, and the relative water content. These three traits were scored in two F-2 populations of 80 individuals for each barley and wheat cross. Analysis of results indicated that the enhanced tolerance to paraquat was correlated with reduced leaf size and increased relative water content, two traits associated with water stress phenotypes of the drought tolerant barley and wheat parents. Our results suggested that the selection based on paraquat tolerance is technically less demanding and thus useful for rapid screening of individuals for enhanced drought tolerance in segregating populations.