The effect of seed size and seeding date on the phenological, morphological and agronomic characteristics of faba bean under rainfed conditions in Gorgan

This experiment was carried out to study of the effects of seed size and seeding date on phenological, morphological and agronomic characteristics of faba bean under rainfed conditions in Gorgan. The experiment was conducted using Barakat cultivar at the research field of Gorgan University of Agricultural Sciences in 2013-2014 growing season. The experimental design was a split plot in a randomized complete block design with four replications. Planting dates (26 Nov., 19 Dec., 2013 and 11 Feb. and 10 Mar., 2014) and seed size (small, medium, large) were arranged in main- and sub-plots, respectively. According to the results, emergence rate of seeds planted in 26 Nov. and 10 Mar. was higher than the other two planting dates, and the emergence rate of small and medium seeds was more than large seeds. Also, time to maturity was 190 days on November planting date. Time to maturity was decreased with delay in planting date, and reduced to 86 days on March planting. The results showed a significant reduction of the number of branches per plant, number of pods per plant, number of seeds per pod and 100-seed weight which led to reduction in green pod and grain yield with delay in planting, respectively. Based on the results of this experiment, to achieve further yields of faba bean under rainfed conditions in Gorgan, early planting and use of larger seeds for planting is recommended.