Evaluation and Selection of Safflower (Carthamus tinctorius L) Genotypes Under Salinity Stress Conditions

To evaluate safflower genotypes under saline conditions and select tolerant genotype(s), 18 safflower genotypes obtained from Dryland Agricultural Research Institute, Iran, were planted at three salinity levels (2, 6, and 12 dS m-1) as main plot and genotypes randomized in subplots using split plots arrangements in randomized complete block design with three replications in Sadough salinity research station, Yazd, Iran, in 2016-17 and 2017-18 growing seasons. Gentypes were selected based on their performance at different salinity levels as well as using stress tolerance indices. The mean reduction in seed yield in the first and second growing season at 12 dS m-1 salinity level relative to control was 36% and 51%, respectively. The STI, MP, GMP, HM, Yis, Yip and MSTI1 indices were highly correlated with seed yield in three environments. Using principal component analysis the first component designated stress tolerance and the second component was salinity stress susceptibility. The results of cluster analysis using stress tolerance indices that had high correlations with seed yield showed that genotypes 4, 26, 34 and 35 were superior to control (cv. Faraman) and grouped in one group, however, genotype 6 performed the same as control. Selected genotypes had higher seed yield in three salinity conditions. In conclusion, LRV-57-57, 26-S6-58-11, Local Kurdistan, Isfahan 4 and PI-537682 with average seed yield of 172, 120, 152, 155 and 141 g m-2, at 12 dS m-1 salinity level, respectively, were selected as salinity tolerant genotypes.