Yield component analysis and recombinative heterosis of complex characters in QPM maize

• Main Author: A.Thanga Hemavathy, N.Subbaraman, S.M.Ibrahim and K.Balaji
• Format: Article
• Language: English
• Published: Indian Society of Plant Breeders 2010-12-01
• Series: Electronic Journal of Plant Breeding
• Subjects: Maize; QPM; component analysis; progeny prediction
• Online Access: http://sites.google.com/site/ejpb10/vol-1-6/Vol-1-6-1474-1479.pdf?attredirects=0

Component analysis is the analysis of variation of complex character based on the variation of its components. For assessing the variation,components should be arranged in ontogenetical order. This allows determination of the mutually independent contributions of the components tothe variation of complex character. Component analysis provides the necessary data for the exploitation of recombinative heterosis in plantbreeding. Recombinative heterosis is the phenomenon where in, the progeny value of a complex character exceeds the mid parental value as aresult of the multiplicative relationship between the complex character and its component traits. It is suggested that this form of heterosis may bean important cause of specific combining ability. As such, it may be involved in the heterosis of complex characters in F1 hybrids and in thehybrid- vigor encountered in interspecific hybrid populations. It is demonstrated how recombinative heterosis may be explained by a quantitativegenetical model involving additive inheritance of the component traits. Current study was focused to predict progeny performance for thecomplex character from parental data for the component traits. This requires regression of individual components on the preceding primarycharacters. The contribution of the coefficient for yield component C3 (single seed weight) to variance of log yield was maximum in the parentsCML 189, UMI 814, CML 145, UMI 524, CML 141 followed by the coefficient C2 (number of kernels per row) which was maximum in theparents UMI 427 and UMI 814. In the present investigation, 35 hybrid combinations were tested for progeny prediction value. Application of thisprocedure revealed that among the 35 crosses, five crosses exceeded the predicted mid parental value. The predicted values can serve as a basisfor the selection of promising combinations. The crosses that exhibited higher values for grain yield per plant was predicted in the combination ofCML 142 x UMI 426, CML 143 x UMI 427, CML144 x UMI 189, CML 144 x UMI 426 and CML 147 x UMI 426.