Gene Effects for Agronomic Traits in Safflower (Carthamus tinctorius L.) under Drought Stress

The mode of agronomic traits inheritance was investigated in safflower (Carthamus tinctorius L.) in drought stress as a new report. Five generation including P1, P2, F1, F2 and F3 that derived from the cross of IL.111 (drought sensitive) ×Mex.22-191 (drought tolerance) were used in a randomized complete block design with two replications. Generation mean analysis was used to estimate genetic parameters. The additive model [d] was fitted for seed-weight, dry weight/plant and number of seeds/plant. The simple additive-dominance model [d, h] was fitted for number of seeds/ capsule. Additive-dominance model was not adequate for plant height, number of branches per plant and number of capsules per plant. Hence, dominance× dominance epistasis [l] was added to fit the model as [d, h, l] for these traits. So, the genetic control of mentioned traits was under additive, dominance and dominance× dominance gene effects. Obtained results could be suitable for designing of breeding strategies to improve seed yield of safflower in drought stress. The highest value for broad-sense (0.94) and narrow-sense (0.9) heritability were denoted to seeds/capsule.