Genetic diversity among barley (Hordeum vulgare L.) Landraces from southern ethiopia

Abstract

Barley landraces are the major genetic resources of cultivated barley in Ethiopia. Lack of adequate information on extent of landraces diversity hinders conservation efforts and proper utilization of genetic resource. A field experiment was conducted in order to assess the extent of genetic diversity of barley landraces collection from southern Ethiopia. A total of 105 genotypes were evaluated during 2018 main cropping season using augmented design at Alarigata, substation of Bonga Agricultural Research Center. Data were recorded for twelve quantitative and seven qualitative characters. Analysis of variance indicated highly significant variation (p<0.01) among 105 genotypes for all traits except awn length. Genotypic coefficient of variations (GCV) varied from 4.36% for biological yield to 13.22% for number of fertile tillers per plant and phenotypic coefficient of variations (PCV) varied from 6.40% for plant height to 16.27% for spike length. Estimate of broad sense heritability varied from 38.75 % for spike length to 78.13 for grain yield. Estimates of genetic advance as percent of mean ranged from 7.61% for plant height to 23.01% for number of fertile tillers per plant. Phenotypic and genotypic correlation analysis indicated that grain yield had positive and significant phenotypic and genotypic correlation with days to maturity, grain filling period, and plant height, number of fertile tillers per plant, thousand seed weight, harvest index and biological yield. Path analysis revealed that plant height, thousand seed weight and number of fertile tillers per plant showed positive and highest direct effect on grain yield. Cluster analysis grouped 105 genotypes into five groups and one genotype remains ungrouped. Principal component analysis revealed that the variance of 31,15,12,10 and 9 % were extracted for first five PCs respectively, which contributed 78% of total variation among genotypes. Estimate of Shannon -Weaver diversity index H’ varied from 0.09 for hoodedness to 0.97 for kernel row number. Pooled over all traits with in each zone, H’ value ranged from 0.48 for Sidama to 0.69 for South Omo and individual trait showed different levels of diversity across different zones. In general, the result indicated the existence of wider diversity among the barley collection, showing opportunity to improve important traits of the crop and need to conserve the diversity. As future line work further investigation with inclusion of informative molecular markers and covering different producing area of the region will allow to provide the complete picture of existing diversity.