Effects of Seedling Stage Drought on Seed Yield, Oil Rate and Oil Yield in Safflower (Charthamus tinctorius L.) Genotypes

Objective of this study was to evaluate the responses of safflower genotypes in terms of seed yield, oil content and oil yield against seedling stage (rosette stage) drought occurring in natural conditions in Konya province where spring drought is frequently observed with the help of drought Sensitivity Index (DSI). The study was conducted in 2018 and 2019 with four replications as a randomized blocks, with 6 registered varieties and 17 genotypes obtained by selection. In 2018, the total amount of precipitation in the safflower seedling stage (May) was well above the average for many years, while this value was 10 mm in May 2019, and it was well below the average for many years. Seedling drought conditions occurring in these natural conditions provided an opportunity to evaluate the reactions of safflower genotypes to stressful and stress-free conditions. According to the results of the analysis of variance based on the values of the stress-free (2018) and stressful (2019) values in the study, it was found to be significant compared to 1% for genotype, stress and genotype stress interaction, seed yield, oil content and oil yield characteristics. In terms of seed yield, when the drought sensitivity index values of the genotypes included in the experiment were examined, G1 was determined as the most susceptible to drought (1.50), followed by G6 (1.33) and G8 (1.19). When the drought sensitivity index values of the standard varieties were examined, Dincer (1.19) variety was determined to be the most sensitive variety. The drought sensitivity index was lowest, therefore drought most tolerant genotypes were G13 (0.48), G14 (0.53) and G15 (0.65). Among the registered varieties, Balci ( 0.92) has been identified as the most drought tolerant variety. It has been determined that the effect of seedling stage drought stress occurs differently in each genotype. Although the oil content was significantly affected by drought, this effect was decreasing in some genotypes while it increased in some others. The effect of safflower genotypes on oil yields from seedling drought was similar to seed yield.