1 Pepper Research Station, Kerala Agricultural University, Kanhirankad P.O., Kannur 670 142.
2 National Res. Centre for DNA Fingerprinting, National Bureau of Plant Genetic Resources, New Delhi 110 012.
3 National Research Centre for Plant Biotechnology, Indian Agricultural Research Institute, New Delhi 110 012.
A study was undertaken to differentiate photoperiod sensitive and photoperiod insensitive rice varieties and to identify putative RAPD marker(s) associated with the trait. The genetic diversity analysis among photoperiod sensitive and photoperiod insensitive rice varieties using different DNA amplicons, grouped 40 varieties into two major clusters and nine sub-clusters. Sixty five per cent of photo sensitive varieties and 60% photo insensitive varieties were grouped in distinct clusters. The result indicated that response to photoperiod had played a major role in the pattern of clustering. The most distant pairs of rice varieties revealed from genetic distance are Bhagya and Ptb 12, Bhagya and Ptb 7, Sagara and Bhagya, and Dhanya and Bhagya. These distant varieties can be utilized in future breeding programmes as parents to get promising recombinants.
Rice, photoperiod sensitivity, molecular markers, RAPD, Jaccard's similarity index, cluster analysis
