Determination of Combining Ability and Hybrid Authentication Using Molecular Markers in Wheat

Abstract

Wheat is one of the most important cereal crop and present study is conducted to explore the potential of experimental material for high grain yield and protein contents through a planned breeding programme. In the proposed study molecular markers have also been planned for the detection of polymorphism as well as hybrid purity assessment for the improvement of yield and quality in wheat. Ten wheat cultivars/ lines were hybridized according to Line × Tester fashion in randomized complete block design with triplicates. Data was recorded for various quantitative and qualitative traits and then it was subjected to biometrical analysis. Significant variability was observed between parents and their hybrids. This study revealed the importance of general combining ability (GCA) as compared to the specific combining ability (SCA). Line WN-146 showed significant positive GCA for number of spikelets per spike, number of grains per spike, grains weight per spike and grain protein contents. Chakwal-86 and Punjab-11 showed significant GCA effects for grain yield per plant among testers. Punjab-11 and WN-146 were found to be the best general combiners among testers and lines for grain yield as well as grain protein contents. Cross combinations WN-146 x Miraj-08, WN-136 x Punjab-11, and WN-64 x Punjab-11 exposed highest positive and significant SCA effects for grain yield per plant. Crosses WN-122 x Miraj-08 and WN-64 x Chakwal-86 had best SCA for grain yield and protein contents. The results of the genetic studies showed that almost all the traits except total soluble sugars showed additive genetic effects with moderate to high heritability. Heterosis studies showed that hybrid vigour existed could be exploited for the commercial production of wheat and selection of enviable crosses is the best option to improve the wheat grain yield. The cross combinations WN-113 x Saher-06, WN-136 x Chakwal-86, WN-64 x Aas-11, WN-64 x Saher-06 and WN-122 x Miraj-08 were the superior hybrids which could be further exploited because of their potential to produce high yield as well as nutrition. Substantial heterosis (23.79%) and heterobeltiosis (20.37%) for grain protein contents was shown by the cross WN-136 x Chakwal-86. Cross combinations WN-64 x Aas-11, WN-64 x Punjab-11, WN-122 x Aas-11 and WN-136 x Saher-06 exposed significantly positive and exploitable heterosis and heterobeltiosis for grain yield per plant. Cross combinations WN-122 x Aas-11 and WN-136 x Saher-06 produced better yield and grain protein contents simultaneously. Grain yield per plant is most important and preferred in wheat breeding that revealed significant positive association with flag leaf area, plant height and number of grains per spike but it had strongly negative correlation with grain protein contents. Simple sequence repeats (SSRs) amplifications showed highest similarity between genotypes WN-146 and WN-146 x Aas-11 (84.73%) while the most diverse genotypes were Chakwal-86 and WN-122 x Saher-06 (68.2%). Genetic diversity between the wheat genotypes ranged from 17.4 to 70.3 percent as revealed by using twenty three (SSRs) markers. Confirmation of twenty five hybrids was also verified using SSRs. The information acquired from these results during the current studies may be used to develop high yielding and more nutritive varieties which can produce economic yield.