The Effect of Drought Stress on some Rapeseed Genotypes under Tissue ‎Culture and Field Conditions ‎

Rapeseed (Brassica napus) is recognized as one of the most important oilseed crops worldwide and its development of cultivation has received attention due to the importance of importing oil. The current study aimed to investigate the effect of drought stress on some Rapeseed genotypes under tissue culture and field conditions and to identify stable genotypes in the field. The possible responses of 14 different canola genotypes to Callus induction resulting from Hypocotyl cultivation and evaluation their drought tolerance were studied using Polyethylene Glycol 6000 (PEG 6000) at five different levels, including zero (as control), 10%, 20%, 30%, and 40% PEG concentrations based on a completely randomized design (CRD) with three replications. Measured traits included relative growth rate, growth rate, relative water content, and proline content of the Callus. Furthermore, in the field sector, the genotypes were investigated in four environments (two consecutive years in 2016-2018 under rainfed and irrigated conditions) based on randomized complete block design with three replications. According to the Callus culture results, the assessed traits, except the Proline content of Callus, decreased with increasing stress level. In laboratory conditions, genotype number seven (Dante) was introduced as the superior genotype. The results of Additive Main effects and Multiplicative Interaction (AMMI) analysis showed the significance of both additive effects of genotype and environment and the multiplicative effect of genotype × environment interaction. The results of cumulative additive effects (decomposition of variance) and multiplicative interaction effects (decomposition into principal components) showed that the first two components explained 53.02 and 33.65% of the variance of the interaction effect for oil yield. Dante and SLM-046 genotypes were introduced as stable genotypes.