Investigations into Causes of Sterility

III. Gametocide-induced male-sterile Vicia faba L

Abstract

Meiosis in 2, 2-dichloropropionic acid-induced male-sterile plants of Vicia faba L. has been studied. Meiosis was regular in nearly 70 per cent of total pollen mother cells studied. The remaining cells were characterized by varying degrees of stickiness, which resulted in multiple chromosome associations and in extreme cases clumping of entire complement at prophase and metaphase I. Disjunction of chromosomes in such cells was characterized by bridges and laggards. Bridges some times persisted upto sporad stage. Multipolar spindles were observed at both the divisions of meiosis. In some cells, a wall was laid soon after the completion of first nuclear division, thereby resulting in the formation of dyads. Dyads did not undergo a second division.
All these abnormalities resulted in the formation of 30 per cent polyads with 2-10 microspores. Some of the pollen mother cells at various stages of division, exhibited the phenomenon of “cytomixis”.