Cytological Studies on Saccharum spontaneum L. accessions from Kerala, India

Abstract

Cytological studies on 45 accessions of Saccharum spontaneum collected from the state of Kerala, India showed the predominance of 2n=64 types in the state. Barring one clone IND99-902 which recorded 2n=72, the chromosome number of rest of the clones was found to be 2n=64, which is the most common cytotype in the country. It is likely that the 2n=72 form has originated from hybridization between 2n=64 and 80 types, both of which have been reported from the region. The karyotype of 5 of the clones studied conformed to 1a, 2a or 2b type of Stebbins. Satellite chromosomes were present in 4 clones. Meiosis was largely regular in all the 2n=64 types with predominant bivalent formation. Univalents were few in the range of 0 to 5.6. The clone IND99-902 (2n=72) showed meiotic abnormalities in the form of univalents, laggards and bridges. The 2n=64 types showed high pollen fertility while the 2n=72 type was found to be nearly pollen sterile.