EFFECT OF DROUGHT STRESS BY USING PEG 6000 ON GERMINATION AND EARLY SEEDLING GROWTH OF Brassica juncea Var. Ensabi

To study on effect of PEG 6000 stress on germination and early seedling growth of B. juncea (L.) Czern. var. Ensabi an experiment was conducted in the laboratories of Institute of Biological Sciences, University of Malaya, Malaysia. Seed germination and final germination rate of B. juncea var. Ensabi significantly affected by PEG 6000 concentration. By increasing osmotic potential of PEG 6000, seed germination and final germination were decreased. In distilled water, percentage of seed germination was highest. The higher amount of PEG 6000 concentration in this research (10 and 12 MPa) completely inhibited seed germination. Signs of germination for control and low PEG 600 osmotic potential occurred between 24 and 48 hours after sowing but at higher PEG 6000 osmotic solution it was being later. Most complete germination occurred at 25 o -30 o C. In PEG 6000 solution, the hypocotyl lengths of seedlings decreased with an increase in water stress. Shoots elongation significantly decreased by concentration of 2-8 MPa whereas no hypocotyl elongation at concentration of 10 and 12 MPa and shoot elongation completely inhibited. Keyword: Ensabi, germination, temperature, PEG 6000 concentration, hypocotyls.