Relationship between hybrid performance and AFLP based genetic distance in highland maize inbred lines

Abstract

The objectives of this study were to determine the crossing performance of highland maize inbred lines for grain yield, days to silk and plant height; estimate genetic distance (GD) among the inbred lines and in association with tester parents, and to investigate the relationship of GD with hybrid performance and midparent heterosis (MPH). A total of 26 inbred lines were crossed with six (population and line) testers in a factorial-mating scheme. The F 1' s and the parents were evaluated at five locations in Ethiopia. Nine amplified fragment length polymorphism (AFLP) primer pairs were used to genotype all the parents. The F 1' s were found to vary widely for grain yield and other traits measured. Yield superiority of more than 30% over the best hybrid check was obtained for some testcross hybrids. Midparent heterosis on average was moderate for grain yield and, plant height. And for days to silking, MPH values were mostly negative. Mean GD values determined from the inbred lines by population tester (0.680) and line tester (0.661) combinations were not significantly different. Cluster analysis separated the tester parents from the corresponding inbred lines. AFLP grouping of the inbred lines was in agreement with their pedigree records. Genetic distances derived from the inbred lines × all testers and from the population testers' sub-group were not positively correlated with hybrid performance and MPH for most traits. In contrast, correlations of GDs involving the line testers' sub-group with F 1' s and MPH were significantly positive but with low magnitude to be of predictive value.Abbreviations AFLP Amplified fragment length polymorphism -GD Genetic distance -MPH Midparent heterosis

Bayesian analysis of the genetic structure of a Brazilian popcorn germplasm using data from simple sequence repeats (SSR)

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Phylogenetic Relationships Among Teosinte, Maize and Its Hybrids

“…The relationship between molecular marker distance and heterosis remains unclear. Some of the reports state significant association (Lanza et al, 1997;Amorim et al, 2006;Srdic et al, 2007) whereas, the others state non-significant or no association between markers based GD and heterosis (Shieh and Thseng, 2002;Legesse et al, 2008;Devi and Singh, 2011).…”

Concept of Heterotic Group and its Exploitation in Hybrid Breeding

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