Soybean seed field emergence and germination test for planting under drought condition

Study of soybean seed field emergence and germination test for planting under drought condition was conducted at Hat Yai, Songkhla. High, medium, and low quality seeds of CM 60 and SJ 5 with 87-100, 74-85, and 54-67% germination were used. Field emergence was studied under every day watering and simulated drought conditions. Germination percentage, shoot height and shoot dry weight were evaluated at 8 days after planting. Germination test under water limitation was done at room temperature by planting the seed in 1 kg of soil in a plastic basket sized 19×26×6 cm at 1 cm depth and watering at 40 and 50% of plant available water (PAW) every day and every 2 days. Seed germination was evaluated at 5 days after planting. The results showed that field emergence of soybean seeds decreased as seed quality decreased. Field emergence index (FEI) could be used to calculate the field emergence of soybean seed from standard germination because all seed quality levels had nearly the same FEI under each field condition. It was observed that the germination test under every 2 days watering at 50% of PAW gave the same germination percentage as field emergence under drought planting condition.