study of black cumin (nigella sativa l.) germination attributes and seed vigur under salinity stress by osmopriming accelerators pretreatment

soil and water salinity in arid and semi-arid regions, is one of the most important stresses, can severely limit crop production. black cumin (nigella sativa l.) is annual important herbal plant in rununculaceae family that sense to salinity. this study was conducted to evaluate the effects of the priming on seed germination of black cumin under saline stress. the experiment was carried out as factorial based on completely randomized design (crd) with three replications. the experimental factors were salinity stress including: (0, 62.2, 124.2, 186.2 and 248.8 mm) and three levels of priming, seed primed with kno3 (0.2 %, for the period of 72 hours), ga (500 ppm, during 48 hours) and hydro priming (water distiller, during 24 hours). a saline stress level treated by applies of nacl, and for priming of distiller water use hydropriming technique. at the first stage, black cumin seed was treat and dried at 25°c, then subjected to saline stress treatments for two week at room temperature. the results showed that priming technique had a significant effect (p≤0.01) on seedling parameters. among pretreatment, the kno3 had the most positive effect on germination coefficient (gc) and thus ga had the most positive effect on mean germination time (mgt). in order hand, these seeds at the minimum time had the most germination rate. means comparing showed that the most and least rate of germination was obtained by kno3 and hydro priming respectively. so under different level of saline stress, pretreatments of kno3 and hydro priming had useful effect on radical length, more lateral roots and higher proportion of root to plumule, and the most root and plumule fresh weight was obtain by hydro priming pretreatments. so pretreatment of 500 ppm ga reduced number of abnormal seedlings.the simple correlation coefficients showed that radical length with mean germination time (mgt) had significantly negative coefficient (r2=-0.726**), with abnormal seedlings number had no significant coefficient and with other measured attribes had positive significant correlation. so mgt with measured parameter (except for number of abnormal seedlings and proportion of root to plumule dry weight), had significantly, negative coefficient correlation. overall, application of seed priming with kno3 (0.2 %) for the period of 72 hours and ga (500 ppm) during 48 hours suggested for obtain uppermost germination characters.