1 (2) 2017, NOVEMBER,2017
Studies on combining ability through line × tester analysis in maize
Author: B.V.V. Vara Prasad and D. Shivani
Category: Plant breeding
Combining ability for grain yield and its contributing characters was carried out in maize through line × tester analysis (L x T) of 45 hybrids developed by crossing 15 females and 3 testers along with three checks. The 45 hybrids along with 18 parents and three standard checks were grown in randomized block design with three replications and were evaluated for seed yield and its ten yield contributing characters. The experiments were conducted at Agricultural Research Station farm, Madhira of PJTS Agricultural University, Hyderabad during kharif 2015. The analysis of variance indicated the presence of significant variability among the genotypes for most of the quantitative traits studied. Combing ability analysis reveled the predominant role of non-additive gene action for inheritance of most of the characters studied. For ear length, MRC 1070 x BML 7, MRC 1081 x BML 7, MRC 1095 x BML 5, MRC 1132 x BML 13 and MRC 1157 x BML 13 recorded significant positive sca effects. For number of kernels per row, the lines viz., MRC 1081, MRC 1134, MRC 1148 and MRC 1157 and for test weight, the lines MRC 1058, MRC 1091, MRC 1104, MRC 1117, MRC 1125, MRC 1134 and the BML 13 had significant gca effects. For test weight, five crosses viz., MRC 1095 × BML 5 (L×L), MRC 1125 × BML 5 (H×L), MRC 1081 x BML 7 (LxH), MRC 1134 x BML 7 (HxH) and MRC 1117 x BML 13 (HxL) were identified as top specific combiners showing positive sca effects. Five crosses viz., MRC 1132 x BML 5 (LxL), MRC 1150 x BML 5 (HxL), MRC 1150 x BML 7 (HxL), MRC 1070 x BML 13 (H XH) and MRC 1081 x BML 13 (HxH) showed significant sca effects for grain yield per plant. Further, the promising single cross hybrids having a parental combination of high × high, high × low gca effects could be used for the improvement of parental lines for desired characters by selecting in advanced generations.
Keywords: Combining ability, inbreds, line, tester, yield