Differences between two grain sorghum genotypes in adaptation to drought stress. II. Root water uptake and water use

Abstract

A study of two sorghum hybrids, E-57 and TX-671, indicated that differences in grain yield under conditions of low rainfall were associated with increased extraction of soil water at depth. E-57 used less water before anthesis than did TX-671, which was more than compensated for by increased water use after anthesis. As soil water declined in a drying cycle, TX-671 tended to restrict its water use at a higher water content than E-57. The implication of these results is discussed.