Abstract
Harvest of immature soybean (Glycine max (I.) Mem] seed is used in breeding nurseries to reduce generation length. Individual pods are harvested and usually dried intact at ambient conditions. Number of days after flowering (DAF) has been shown to be a good criterion to determine the appropriate time to harvest, but the method is time consuming on a large number of genotypes. The objective of this study was to identify a visual indicator of the appropriate stage for harvest of immature viable seeds. Two indeterminate cultivars, Lakota from Maturity Group (MG) I and BSR 301 from MG III, were planted in three environments at Isabela, PR. Harvest of pods began 28 DAF and continued every 3 days until 46 DAF. Field emergence, fresh and dry seed weights, seed width, seed length, seed thickness, pod angle, pod color and reproductive stage of individual plants were recorded. Results pointed out that the best visual indicator for the harvest of immature seed obtained from green pods was a combination of pod angle, seed dimensions, and reproductive stage of the plant. In general, field emergences of 70% or better were obtained with immature seed of green pods that could be bent no more than 30° before rupturing and that contained seeds at or near their maximum width, length, and thickness. These pods were harvested from plants that had reached reproductive stage R6.