Hybridization and pollen germination in soybeans

Abstract

Anthesis insoybeans was found to occur at between 7.00 a.m. and 8.00 a.m. in south-eastem Queensland. A successful hybridization technique involving high relative humidity is described. The effects of humidity were involved with stigmatic receptivity, rather than with limitations on pollen germination and growth under low relative humidities. Greater pollen germination was obtained at 26.5°C than at 21°C, but germination was suppressed at 33°C. Applications of gibberellic acid stimulated pollen grain germination, and a dual application of gibberellic acid and certain growth substances was slightly more effective than gibberellic acid alone. Individual growth substances had little influence on pollen grain germination.