Abstract

Increased drought incidence due to global warming has been affecting agriculture and wheat production in particular. Insufficient water during germination stage is one of the main constraints for crops which cause reduction in seedling emergence and establishment. At this point of view, this study was carried out to investigate the effect of priming with gibberellic acid GA3 on wheat seed germination (Slemani-2 cultivar) under drought stress. The experimental design was completely randomized design with three GA3 concentrations (0, 100 and 200 ppm), and four stress levels (0, -0.35, -0.70 and -1.40 MPa) of polyethylene glycol PEG 6000 with three replications. The response to drought and priming effect was measured based on some germination (germination rate, mean germination time and germination index) and growth (seedling vigor I and II, radicle and plumule; length, fresh and dry weight) parameters. The results show that increasing PEG concentrations affects most of the parameters. The low dose of GA3 pre-treatments had significant effects on the germination and growth parameters of Slemani-2 cultivar, the best results were obtained from the 0 and 100 ppm GA3, under 0 and -0.35 MPa PEG applications.

Keywords: Gibberellic acid GA3; Drought stress; Polyethylene glycol PEG 6000; Seed germination