Characterization of genetic variability in different rice lines using DNA markers

Rice is one of the important staple food crop in the world. Which has been extensively studied both the genetic and molecular level. New technique based on DNA profiling provides novel approaches to varietal characterization which offer advantage over traditional morphological comparisons. Identification of plant varieties/ cultivars and determination of their genetic variability through direct DNA analysis not only help to identify molecular marker across the chromosome for mapping purpose, it also help in gene tagging as well as molecular marker aided selection (MAS), because of several advantages of the molecular method over the biochemical or morphological methods to identify, characterize and determine genetic variability among rice lines, an attempt has been made to characterize different rice lines containing known genes of blast resistance and some of local cultivar with an objective to study the level of DNA polymorphism among different rice lines using PCR based DNA marker and to estimate the genetic variability among 23 rice lines during the year 2003 at NRCPB, New Delhi. PCR based Random Amplified Polymorphic DNA (RAPD), UPR, ISSR and STMS markers were used for characterization of genetic variability among 23 rice lines. Total 83 primers were used, out of which 30 primers gave polymorphism. A total 1276 number products amplified. Dendrogram was constructed on the basis of the result obtained through PCR. It showed that 23 lines were clustered in to 7 groups. The first group contains 2 isogenic blast resistant lines, second group contains four isolines having different genes of P14. The third cluster contains three rice lines which all contains different genes of PiK, HPU-741 which is local variety, distinguished from the other three variety they having 55 similarity in cluster 4. Three japonica type lines were grouped in cluster five. Cluster 6 having two rice lines which are japonica type having dark nature. Cluster 7 having two varieties which are susceptible for blast.