GENETIC DIVERSITY AND DNA FINGERPRINTING OF SOME MODERN INDICA AND JAPONICA RICE

摘要

The genetic diversity of 22 indica rice (Oryza saliva L.) cultivars, including 12 Bangladeshi modern varieties and near-isogenic lines, and three japonica rice cultivars was determined through DNA fingerprinting using five microsatellite marker loci (RM1, RM3, RM168, RM226, and OSR19) amplified by polymerase chain reaction (PCR). The number of alleles detected in the 25 rice cultivars for these loci varied from 2 to 4 with an average 2.8. The highest number of alleles (4.0) was detected in the locusRM1 and the lowest number of alleles (2.0) was detected on each of locus RM3 and OSR19. The genetic diversity (GD) of these five loci ranged from 0.2496 to 0.6336. The highest GD (0.6336) was detected in locus RM168 and the lowest (0.2496) on locus OSR19. Average GD was 0.4446, indicating a moderate level of genetic diversity existing among the tested cultivars. DNA fingerprinting of the 12 Bangladeshi varieties showed multiple banding in most of the loci which indicated that natural cross pollination might be occurring in farmers' fields and causing heterogeneity in the population and, consequently, yield decline in these rice cultivars in Bangladesh.