Iranian Journal of Seed Research

In order to study, the effects of hydropriming and osmopriming on germination characteristics of Nigella sativa L. under salt stress an experiment was conducted in factorial laid out in completely randomized design with four replications at Research Laboratory, Faculty of Agriculture, Mashhad Branch, Islamic Azad University-Mashhad Iran, in 2014. Factors were included of priming treatment in six levels [control (Non-priming), hydropriming with distilled water, osmopriming with KNO3, KCl, CaCl2 and NaCl] and salinity treatment in four levels [0, 50, 100 and 150 Mmol]. Analysis of variance showed that the effects of salinity and seed priming on all measured indices and interaction between two factors on germination percentage and rate, radicle and plumule length and seed vigor were significant at the probability level of 1%. The results showed that with increasing salt concentration all measured traits were decreased. This decreasing started from the 50 Mmol concentration. Under salt stress condition, osmopriming with KNO3 and then hydropriming and osmopriming with KCl improved all germination indices compared with control.

In order to study the seed germination behavior and dormancy breaking methods of three weed species (i.e., Chenopodium album, Convolvulus arvensis and Setariaviridis) of pistachio orchards in Rafsanjan, Iran, three separate factorial experiments (with 2 factors) were conducted based on a completely randomized design with four replications, at the Faculty of Agriculture, Vali-E-Asr University of Rafsanjan, Iran, in 2014. Weed seeds were collected from five different regions of Rafsanjan, such as Markazi, Anar, Koshkoiyeh, Kabotarkhan and Nogh. Dormancy breaking treatments for Chenopodium album involved distilled water (control), KNO₃ (at 500 and 1000 ppm), chemical scarification by sulfuric acid (for 5 and 10 min), and cold stratification (for 1, 3 and 5 weeks). Treatments for Convolvulus arvensis involved distilled water (control), scarification by sandpaper, chemical scarification by sulfuric acid (20 and 30 min), and boiling water (for 15 and 30 min). Treatments for Setaria viridis involved distilled water (control), gibberellic acid (250, 500 and 1000 ppm), KNO₃ (500 and 1000 ppm), and cold stratification (for 1, 3 and 5 weeks). The results showed that seed germination percentage (SGP) and mean germination time (MGT) of three weed species were significantly different among weed populations and dormancy breaking methods. For Chenopodium album, cold stratification of 5 weeks resulted in highest SGP (97%) in Nogh population. For Convolvulus arvensis and Setaria viridis, the highest SGP was obtained after scarification by sandpaper (98% in Kabotarkhan population) and using 1000 ppm gibberellic acid (60% in Kabotarkhan population), respectively. In addition, increasing the weight of 1000 seeds in the three weed species in question increased SGP.