Determination of sesame (Sesamumindicum L.) genotypes tolerant to water stress and stress tolerance indicators by drip irrigation in semi-arid climate conditions

Abstract

The purpose of this study was to determine the water stress tolerance of sesame genotypes (Arslanbey, Halisbey and H2) grown in water-stress free (SF) (I1 0 0), water-stress (WS) (I7 0) and extreme water stress (EWS) (I3 5) conditions in 2016 and 2017. The experiment was carried out in a split plot design within randomized blocks with three replications. Variance analysis revealed statistically significant (p<0.01) differences between genotypes. The highest yield (HY) (706.56 kg ha- 1) for two-year average in extreme water stress (EWS) treatment was obtained in the interaction of I3 5xArslanbey which had a low plant water stress index (CWSI) (0.56) and a high chlorophyll content (CC) (28.95 spad). The lowest yield (LY) (580.16 kg ha- 1) was obtained in the interaction of I3 5xH2 which had a high CWSI (0.63) and a low CC (27.39 spad). In water stress free (SF) treatment, the HY (1297.07 kg ha- 1) was obtained in the I1 0 0xArslanbey interaction which had a low CWSI (0.16) and high CC (43.83 spad), while the LY (1125.51 kg ha- 1) was determined in the interaction of I1 0 0xH2 which had a high CWSI (0.24) and a low CC (38.60 spad). Significant correlations (p<0.01) were determined among all investigated traits. The results of the study revealed that Arslanbey sesame genotype is a prominent variety in terms of yield both under EWS and SF treatments and optimum efficiency in irrigation water utilization. Therefore, Arslanbey genotype was considered to be tolerant to water stress and can be evaluated in water stress tolerance studies. In addition, the findings of the study indicated that CWSI and CC values of sesame plants can be used as stress screening parameters (tolerance indicator) in breeding studies for the selection of water stress tolerant sesame varieties. © b y PSP