摘要：Four lines and three barley testers were used to estimate resistance to net blotch disease and produc- tivity under normal condition. Through this study, general (GCA) and specific (SCA) combining abili- ties and heritability in both broad and narrow senses were estimated for days to maturity, plant height. spike length, no. of grains/spike, no. of spikes/plant. 100-grain weight, grain yield/plant and net blotch disease resistance. Data revealed that, most of the variances due to the lines, testers and lines x testers were highly significant for most studied traits. The estimates of GCA effects indicated that, line-1 and line-3 were good combiners for net blotch disease. Tester-l was a good combiner for grain yield/plant. Significant or highly significant values in desirable direction for SCA estimates were obtained for net blotch resistance in crosses no. 2, 3, 4. 9 and 12, days to maturity in cross no. 9 and grain yield in cross no. 5. Heritability in broad sense (H2) showed high esti- mates for the studied traits ranged from 91.77% for grain yield/plant to 96.37% for 100-grain weight. Heritability in narrow sense (h2) percentages varied from 10.43% for plant height to 37.94% for net blotch resistance. Expected genetic advance from se- lection (%) ranged from 0.81% for days to maturityto 39.33% for net blotch resistance. The principal component analysis revealed that four components could be described while they recorded 61.7% of to-tal variances. Cluster analysis divided all studied genotypes into two clusters. Overall, results of agro- nomic parameters and those related to the biotic and abiotic stresses will be used for better identifying for these genotypes and better directing studies of ge- netic improvement.
关键词：Hordeum valgare L;Line x Tester;Heritability;Principal component analysis;Genetic advance;Net blotch
