Induced Desynapsis in Grain Sorghum

Desynapsis with reduced pollen and seed fertility was observed in two mutagen treated plants in intervarietal hybrid progenies of Sorghum bicolor (L.) Meonch. These plants showed apparently normal pairing at pachytene except for occasional unpaired distal regions in 1 to 3 bivalents. Variable number of univalents and increased number of rod bivalents were found at diakinesis and metaphase I. Anaphase I and II bridges recorded appear to be due to chromosome stickiness. The degree of desynapsis, however, differed in the two plants as measured by the univalent and laggard formation. It is suggested that two different mutant genes designated tentatively as as5 and as6 are involved.