The effect of sowing date on peanut seed vigor and yield

Determination of proper time for planting and harvesting has special importance. For determination of proper time of maturity with high vigor and yield, an experiment was conducted in two crop years in complete block design in research station of Gorgan University of Agricultural Sciences and Natural Resources (GUASNR). In first and second year the study was performed in five and two planting dates respectively. The Sampling repeats weekly when seed developed in pods and were transferred immediately to the laboratory. Seed germination and moisture content was determined and electrical conductivity test was measured after drying the seeds. Results showed that seed moisture content in final stage, germination percentage, electrical conductivity, seeds filling rate, seed filling period and seedling vigor were significantly affected by planting date. Seeds which planted early had lower moisture content in harvest time and higher germination percentage than seeds which planted late. Different sowing date significantly affected seed yield in the first year, while in the second year delay sowing had no significant effect on total seed yield. Reduce seed filling period in late planting date of first year and facing this period with the end of season rainfall led to significant decrease in seed vigor and quality. results suggested between weather parameters, temperature and rainfall during seed filling period had significant effects on peanut seed vigor and yield. So adjusting planting date according to location weather condition could results high quality and vigor seeds in harvest time.