A Note on The Effect of Different Patterns of Drought Stress on Productivity and Stomatal Conductance in Some Sorghum (Sorghum bicolor) Genotypes

Abstract

Drought stress is one of the major abiotic stresses in agriculture worldwide. Crops demonstrate various morphological, physiological, biochemical, and molecular responses to tackle drought stress. This study was carried out to investigate the effect of two types of drought stress (pre- and post- flowering) on productivity and stomatal conductance in six sorghum genotypes under field experiment for one season (2015-2016). The experiment was laid out in a split plot design with three replicates. Pre-flowering drought stress was applied after 35 days of sowing by withholding water from the stressed plots for three weeks then irrigation was continued regularly until end of season, while post-flowering drought stress was applied after 60 days of sowing by withholding water from the plots until end of season. Significant differences were detected just in head length parameter among the tested sorghum genotypes under pre- and post-stress, while there were no significant differences in other reproductive, yield and stomatal conductance. The genotypes Wad Ahmed, ArfaGadamak and Red Mugud showed more tolerance compared with other genotypes. This information should be important for selection of drought-resistant genotypes for production under diverse environments.