RAPD-based genetic diversity analysis of aromatic rice (oryza sativa. L)

Abstract

Genetic diversity of a total 38 aromatic rice lines and two non-aromatic controls were assessed using the randomly amplified polymorphic DNA (RAPD) technique. Based on their history of collection and pedigree, the rice genotypes were grouped as traditional Basmati (TB), evolved Basmati (EB), exotic aromatic (EA), indigenous aromatic (IA) and non-aromatic (NA) checks. Five RAPD primers, previously used in rice, amplified a total of 44 DNA bands from the set of 40 rice lines ranging from 500bp to 3.5kb in size. Of the 44 DNA bands 41 were polymorphic. Polymorphism information content (PIC) value of each RAPD primer was computed. Similarity coefficients were calculated from the polymorphism between all pairs of the rice lines and a dendrogram obtained using the unweighted pair group with arithmetic mean (UPGMA) method. The analysis indicate that: (1) there is considerable amount of genetic diversity within the genotypes assessed; (2) with a singular exception, the Basmati genotypes are confined to two clusters; (3) a core group of eight TB genotypes show the least amount of variation while rest of the lines, including the other TB, are more variable; (4) the five RAPD primer-generated polymorphism clearly identified each of the 40 rice genotypes distinctively.