ence of Maturity Stages and Drying on Germination, vigor and Leachate of Soybean Seeds During Storage

Abstract

Harvesting seeds at physiological maturity (PM) and drying in the shade offers an effective mean for maintenance of seed quality in soybean [Glycine max (L.) Merr.]. The present study was conducted to evaluate the effects of maturity stages and desiccation on germination, vigor and leachate of soybean seeds during storage. The seeds growing at Lansak District, Uthaitani, during rainy season in 1999 were harvested either at PM or at field maturity (FM) and allowed to air-dry in intact pods either showly under shade in the laboratory or rapidly in full sunlight. The seeds were hand shelled when seed moisture content of 14-15% was achieved and futher dried until moisture content of 8-9% was obtained. Seed at PM with sun drying showed decline in vigor at 120 days of storage. Instead of no change in germination, deterioration appeared by reduction of TZ1 and increased of TZ3 to TZ5. However, such changes were small in seed at PM with shade drying. Seed at FM with sun drying showed apparent leachate at early imbibition through storage period up to 90 days, whereas seed at PM with sun drying showed leachate at 120 days of storage. The results suggested that harvested seeds at PM and drying in the shade could maintain seed quality in storage. This would be a practical method for the farmers to harves earlier and avoid from field weathering.