Pod shattering incidence in relation to seed dispersal and maximum harvest delay in soybean genotypes

The efforts to minimize the pod shattering incidence in soybean can be done by the use of resistant variety and the determination on the limit of harvest delay. The study aims to evaluate the pod shattering resistance and to determine the maximum limit for harvest delay in soybean. Sixteen soybean genotypes were planted during the dry season 2019. After plants reached the F8 phase, ten randomly sample plants were taken from each plot. The examination for the effect of the harvest delay on the pod shattering incidence was based on the simulation on the pot. The experiment was arranged in a randomized block design with four replications. Pod shattering on each fertile node and seed dispersal were observed for twenty days. The number of fertile nodes, number of pods per fertile node, and pod shattering on the fertile node varied between genotypes. The highest number of pods where found at the third node (7.50a ± 4.26) and fourth node (7.44a ± 4.23) from the lower part of the stem. Pod shattering in the nodes at the lower part of the stem (17 % ± 4.96 %) was higher than in the nodes at the middle (8% ± 6.86%), and upper part of the stem (3% ± 3.79%). The evaluation for pod shattering resistance resulted in two very resistant genotypes, ten resistant, two moderately resistant, one susceptible, and one very susceptible genotype. The seed dispersal of very resistant and resistant genotypes ranged from 0 - 8.55%, the moderately resistant genotypes were 12 – 15%, and the susceptible and very susceptible genotypes were between 23.72 – 48.65%. The harvest delay in resistant or very resistant genotypes could be done 20 days after maturity, meanwhile in susceptible and very susceptible genotypes, the harvest delay should not exceed three days after maturity