Grain yield and drought tolerance indices of maize hybrids

Abstract

Drought is one of the major abiotic stress factors limiting crops production in Oltenia area, Romania. In order to study the response of six maize hybrids to drought stress, the trials were conducted in research field of ARDS Simnic – Craiova, during 2017-2018 (non-stressed conditions) and 2018-2019 (drought stress). Six tolerance indices including: abiotic tolerance index (ATI), stress susceptibility percentage index (SSPI), Stress tolerance index (STI), mean productivity (MP), relative drought index (RDI) and golden mean (GM), were utilized on the basis of grain yield. Results from analysis of variance showed that there is a significant difference in 1% of probability level among hybrids in terms of grain yield and tolerance indices. The yield in non-stress conditions (Yp) showed significant positive correlations with ATI, SSPI, STI and MP, and negative correlation with RDI and GM. The yield  in drought conditions (Ys) showed significant positive correlation with RDI and GM, and negative correlation with ATI and SSPI. None of the tolerance indices used could identify the high yielding hybrids under drought and non-stress conditions. Based on the ranking method, the hybrids ‘Felix’ and ‘P 9903’ were the most droughts tolerant. Therefore, they hybrids are recommended to be grown under drought prone areas and to be used as parents for breeding of drought tolerance in other cultivars.