Pollen dimorphism in soybean.

Microspores of soybean plants ( Glycine max (L.) Meer.) of four cultivars were cytologically analysed. The pollen grains showed a clear dimorphism when stained with propionic-carmine from binucleate stage onwards. The majority of the grains are large, deeply stained and with asymmetric division ('normal type') while the remainder grains are smaller, lightly stained, uninucleate or with two similar nuclei ('P-pollen'). The different frequencies of 'P-pollen' on the four cultivars suggest a genotype effect of microspore dimorphism. [ABSTRACT FROM AUTHOR]