Application of hydrotime model to predict seed lots emergence of wheat

Hydrotime analysis of seed lots allows them to be ranked them according to their potential for successful emergence. An experiment was done on 10 wheat seed lots (N-80-19 cv) to evaluate water potential for determining seed vigor by hydrotime analysis in research field and seed research laboratory on the Gorgan University of Agricultural Sciences and Natural Resources. Seed lots were planted in complete block design whit three replications in field. Water potential was created with PEG6000 at seven levels (0, -0.3, -0.6, -0.9, -1.2, -1.5, and -1.8 MPa). Maximum germination percent for all seed lots were same. Because there were significant differences in maximum emergence percent in field for seed lots it was demonstrated that seed lots vigor were significantly different. According to hydrotime model's parameters, the seed lots that had more emergence their hydrotime constant (θH) were lower, but their base water potential (Ψb(50)) were higher. Uniformity constant (σψb) for all seed lots were same. Unlike the maximum germination percent result, the hydrotime model output results showed that there is difference in terms of seed lots vigor among this study's seed lots. This study results demonstrate that hydrotime model has a great ability in determining wheat seed lots vigor. This model can predict emergence percentage in stressful situations.