FRESENIUS ENVIRONMENTAL BULLETIN, cilt.27, sa.4, ss.2476-2482, 2018 (SCI-Expanded)
Maize production in all over the world is influenced unusually due to continuous global climate change. Considering the important issue, the present study was designed to evaluate the response of maize hybrids to drought tolerance in relation to grain weight at grain filling sage. The experimental materials were comprised seven maize hybrids viz., 'Sancia', 'Indaco', '71 May 69', 'Aaccel', 'Calgary', '70 May 82' and '72 May 80'. These hybrids were evaluated at grain filling stage under two moisture levels (normal irrigation and water deficit condition). Different drought tolerance indices including stress susceptibility index (SSI), stress tolerance index (STI), geometric mean productivity (GMP), tolerance index (TOL), mean production (MP), yield index (YI), yield stability index (YSI), drought resistance index (DI), yield stability index (YSI) and stress susceptibility percentage (SSP) were calculated to evaluate the maize hybrids that are tolerance to drought stress in relation to grain weight. Two years experimental results revealed that yield traits of maize hybrids adversely affected by water stress (drought) conditions due to the reduction in grain weight. However, for increasing yield of maize hybrids under drought conditions can be achieved by selection of maize hybrids according to grain weight. In case of stress tolerance indices, genotypes with high values of STI, GMP, YI, YSI, DI, HM and MP can be recognized as drought tolerant genotypes. Among the tested maize hybrids, '70 May 80', Aaccel' and 'Indaco' were selected as drought tolerant genotypes on the basis of STI, GMP, YI, YSI, DI, HM and MP. However, lower value of SSI and TOL can be selected as tolerant genotypes to stress. While, genotypes, 'Sancia', '71May 69', 'Indaco' and 'Calgary' were identified as drought resistant genotypes and desirable for stress condition on the basis of SSI and TOL. Interestingly, positive and strong relationship between stress indices, SSI, TOL, STI, GMP, YI, YSI, DI, HM, MP and SSP, and grain weight could be used as selection criteria for maize hybrids responses to drought stress.