Sharma, HemlataSapna2017-10-022017-10-022016Sapna and Sharma, 2016http://krishikosh.egranth.ac.in/handle/1/5810032016Heterosis and Combining Ability Analysis for Yield and its Contributing Traits in Indian Mustard [Brassica juncea (L.) Czern & Coss]Heterosis and Combining Ability Analysis for Yield and its Contributing Traits in Indian Mustard [Brassica juncea (L.) Czern & Coss] The present investigation consisted of 76 entries including 56 hybrids along with 18 parents and 2 checks viz., NRCHB-506 and DMH-1 were evaluated during Rabi 2015-16 in randomized block design with three replications. The data were recorded for conclusion it was 14 traits to study the magnitude of relative heterosis (RH), heterobeltiosis (HB), economic heterosis (EH) and general and specific combining ability effects. The analysis of variance revealed that the mean square due to genotypes, parents, crosses and parents v/s crosses were significant for all the traits. The per se performance indicated that the inbred line L5 exhibited maximum mean values for grain yield per plant, and biological yield per plant . While the line L11 exhibited maximum mean values for number of siliquae per plant, number of seed per siliqua and harvest index. Line L8 exhibited maximum mean values for length of main branch and 1000 seed weight. Line L7 exhibited maximum mean values for number of primary branches per plant. Line L3 exhibited maximum mean values for number of secondary branches per plant. Line L10 exhibited maximum mean values for length of siliqua. Line L7 exhibited minimum mean values for days to 50 % flowering, days to maturity and plant height. The Line L10 or L5 depicted highest mean values for oil content. Five crosses L3 x T2, L4 x T4, L6 x T3, L10 x T1 and L8 x T1 depicted positive significant economic heterosis ranged from 13.81 to 23.08 for seed yield per plant over the best check DMH-1. In addition to this cross L14 x T2 also shows significant positive economic heterosis for oil content over the best check NRCHB-506. Similarly maximum heterobeltiosis exhibited by cross L4 x T4 and maximum relative heterosis exhibited by the cross L3 x T2 for seed yield per plant. Majority of the crosses exhibited significant negative relative heterosis for maturity traits and plant height indicated that for these traits the genes with negative effects were dominant.. . The analysis of variance for combining ability indicated that the mean squares due to crosses, lines and testers were significant for all the traits, except for the Plant height in line and number of seeds per siliqua , seed yield per plant (g), 1000 seed weight, biological yield per plant and harvest index in tester. Besides this, the ratio of  2 sca /  2 gca was greater than one fo the traits viz; plant height, length of main branch, number of siliquae per plant, length of siliqua, 1000 seed weight, biological yield per plant and harvest index. This indicated role the preponderance of non-additive gene effects in the expression of these traits. Parental line L3 and L8 has been found good general combiner for majority of traits. Crosses L3 x T2, L4 x T4, L6 x T3, L8 x T1 and L10 x T1 showed high positive sca effects along with good per se performance and positive significant economic heterosis for seed yield per plant.Thus, a close relationship among sca effects, economic heterosis and per se performance for grain yield per plant and oil content was observed among these crosses. These crosses could be recommended for multi locational trial and lines L3, L8 and L10 be used to develop a variety by utilizing additive gene effects.ennullThesis