Investigations into causes of sterility IV. Gametocide-induced male-sterilePhaseolus aureus Roxb.

Abstract

Phaseolus aureus Roxn, cultivar T₅₁ was treated with aqueous foliar sprays of 0.01, 0.025% and 0.05% 2,2-dichloropropionic acid (DPA) just before the initiation of floral buds when the plants were 25 days old. Flower buds were fixed 10 days after treatment. The plants in the two latter treatments were 100% pollen sterile. Meiosis in these treatments was characterized by multivalent associations at diakinesis and metaphase I. These associations were found to be due to stickiness, produced by agglutination of chromatin. Both the divisions of meiosis were characterized by sticky chromosome bridges and laggards, resulting in the formation of micronuclei and consequently polysporads. Histology of anthers revealed a vagary in the behaviour of the tapetum.