DROUGHT TOLERANCE INDICES OF SELECTED LANDRACES AND BREAD WHEAT (TRITICUM AESTIVUM L.) GENOTYPES DERIVED FROM SYNTHETIC WHEATS

The present study was performed to determine performance of selected four synthetic derived bread wheat genotypes, four bread wheat landraces and four modern wheat genotypes under rain-fed and supplemented irrigation experiments based on randomized complete block design with four replications at GAP International Agricultural Research and Training Center, Diyarbakir, Turkey in 2013-2014 and 2014-2015 growing seasons. According to results of pairwise correlation and biplot analysis, significant and positive correlation was observed between grain yield in stress condition (Ys) and stress tolerant index (STI), geometric mean productivity (GMP), mean productivity (MP), harmonic productivity (HM), yield stability index (YSI), yield index (YI), drought resistance index (DI) and stress non-stress production index (SNPI) indicating these indices can be used as parameters for evaluating drought tolerant genotypes. Negative correlation between grain yield in stress (Ys) with SSI and no correlation with TOL indicated that these indices should be used in severe drought conditions for screening genotypes. Number seed in spike (NSS), plant height (PH) and thousand kernel weight (TKW) correlated with grain yield in stress conditions (Ys) according to biplot analysis, also genotypes with lower reduction relating to these traits had higher yield in stress conditions. According to results SEN-DER genotypes G7, G10, landrace group genotype G11 (Sorik) were determined as the most tolerant genotypes to be used to improve drought tolerant varieties, while modern wheat genotypes G4 (Ceyhan-99) and G2 (Tekin) were high productive in irrigation conditions and low productive in rain-fed conditions.