Meiotic Abnormalities in Intergeneric Hybrids between Saccharum spontaneumand Erianthus arundinaceus (Gramineae)

Abstract

Cytological studies were made in hybrids between S. spontaneum L clone Iritty-2 (2n=64) and Erianthus arundinaceus (Retz.) Jesweit clone IK 76-99 (2n=60). The chromosome number of 19 hybrids ranged from 2n=78 to 86. Predominantly bivalent formation was observed at diakinesis and metaphase I stages in pollen mother cells of all the hybrids. At later meiotic stages abnormalities such as lagging chromosomes, multipolar spindles, abnormal planes of cytokinesis and micronuclei were present. In one hybrid CYM 04-391 with chromosome number 2n=80, the pollen mother cells had cytomixis and syncyte formation in the prophase stage. Certain syncytes had very high number of chromosomes in the form of bivalents at diakinesis and metaphase I, with nearly 80 to more than 600 bivalents. Fertile pollen was observed in few anthers of CYM 04-391 and the pollen size variation was high in it compared to that in the other similar hybrids.