Cytomorphological Studies on a Saccharum spontaneum L. Clone from the Car-Nicobar Island, India

The Andaman-Nicobar group of Islands is located in the Bay of Bengal between the Indian subcontinental and the Thailand-Malaysia-Indonesia region. A Saccharum spontaneum L. clone was collected from the Car-Nicobar Island during a germplasm-exploration conducted in the Island in March 2003. This is the first collection of S. spontaneum from the Island. The chromosome number of this clone was examined in relation to the distribution of different cytotypes of S. spontaneum in the region. The somatic chromosome number of the clone was found to be 2n=88, which is not a common cytotype in the neighbouring areas including the Indian subcontinent and the Indonesian archipelago. The possibility of its origin through the natural hybridisation between 2n=80 and 96 forms of S. spontaneum is discussed. Cytotypes with 2n=80, 96 and 88 chromosomes are present in Thailand and it is likely that this clone originated in Thailand and spread to Car-Nicobar subsequently.