Study of Genetic Diversity by RAPD Markers and Identification of Informative Markers for Grain Yield and its Components in Hulless Barley Genotypes

Abstract

Twenty hulless barley genotypes were assessed by 85 RAPD markers having 10 bps. Thirty five markers (41%) had suitable polymorphism using 227 amplified markers. The average number of amplified segments was 6.48. The size of amplified products varied from 400 to 2700 kb. Primer 540 had the highest and primers 498, 559, 577 and MT9 had the lowest amplified segments. Jacard similarity coefficient ranged from 0.3770 to 0.8. The highest similarity was observed between genotypes no. 15 and 16 (0.8) and also between no. 2 and 3 (0.759). The cluster analysis based on Jacard similarity and complete linkage method classified hulless barley genotypes into three groups. The results of the cluster analysis corresponded with the pedigree of the genotypes and the genotypes with the similar pedigree were grouped mostly in one cluster. This suggests the efficiency of RAPD markers in detecting genetic diversity of hulless barley germplasm. Principal coordinates analysis showed that five coordinates accounted for only 42.58% of variation which indicated the proper distribution of markers in the hulless barley genome because of relatively low percentage determined by the five first coordinates. Diversity of hulless barley genotypes was also evaluated by 25 agronomic characters using the range of every trait as a percent of mean. The results showed the existence of considerable variability among the genotypes for most of characters. Analysis of regression showed that 20, 19, 18, 14, 11 and 10 markers were informative for spike length, number of grains per plant, grain yield per plant, number of effective tillers, heading date and 1000 grain weight, respectively. From 18 informative markers for grain yield eight were similar with the markers informative for the number of grains per plant which suggests that from molecular view point this character could be regarded as the most important component of grain yield per plant in hulless barley