Chromosome Number, Meiosis and Pollen Fertility in Vicia rigidula Royle and V. tenera Grah. from Cold Desert Regions of India

抄録

We have recorded the meiotic chromosome counts in 2 species, Vicia rigidula (n=12) and V. tenera (n=7) from the cold desert region of Kinnaur district of Himachal Pradesh (India). V. rigidula which exists at tetraploid level (x=6) and depicts the phenomenon of cytomixis involving chromatin transfer in 6.52% of the observed pollen mother cells (PMCs) during different meiotic stages. 3.43–12.20% of PMCs also show non-synchronous disjunction of a few bivalents, laggards and chromatin bridges during anaphases/telophases, and micronuclei and included micronuclei in tetrads. Products of such aberrant PMCs result in the formation of sterile/unstained pollen grains and fertile/stained pollen grains of variable sizes. The meiotic course in V. tenera, which is diploid (x=7), depicts normal meiotic behaviour in the majority of the PMCs. Only a few PMCs (0.20–1.20%) depict some meiotic disturbances during anaphases resulting in the formation of 6.00–7.20% sterile/unstained pollen grains.