Heterosis, molecular diversity, combining ability and their interrelationships in short duration maize (Zea mays L.) across the environments

Abstract

Five inbred lines, 10 single cross maize (Zea mays L.) hybrids and two standard cultivars as check were used to study the combining abilities and heterosis under three environmental conditions. Random amplified polymorphic DNAs (RAPDs) markers were used to study the genetic diversity (GD) and further to analyze relationship of RAPDs based GD with combining ability and heterosis in short duration maize. Spearman's rank correlation coefficients and linear regressions were analyzed to identify the most important factor determining heterosis and per se performance of the hybrids. Variances due to general combining ability (GCA), specific combining ability (SCA) and their interactions with environment were found to be significant. Twenty random primers generated 179 RAPD fragments. Of these, 102 RAPD fragments were polymorphic. GD was determined using Jaccard's similarity coefficient, and a dendogram was constructed by UPGMA cluster analysis. The RAPDs based GD exhibited non-significant negative or positive association, non-significant linear regression along with very low coefficient of determination (R 2 ) with SCA, high and mid parent heterosis (HP and MP) and per se performance of the hybrids. Significant positive correlations and regressions along with high coefficients of determination were recorded for SCA with HP, MP and per se performance of the hybrids. The HP and MP also established significant positive association and linear regression along with high coefficient of determination with per se performance of hybrids whereas the parental mean did not establish any significant correlations with the GD, HPH, MPH and grain yield of F 1 s. The present investigation, therefore, did not find any role of RAPDs based GD in determining hybrid heterosis and hybrid performance in short duration sub-tropical maize. The SCA, however, has emerged as the most important factor in determination of heterosis as well as per se performance of the hybrids in short duration maize.

Phylogenetic Relationships Among Teosinte, Maize and Its Hybrids

“…GD mor had highly significant positive correlation with plant height of maize par-ents and reciprocal hybrids with values 0.968 and 0.908, respectively. These results corroborate with previous studies (Lee et al, 2007;Devi and Singh, 2011). The ability to predict heterosis levels using genetic distance between the parents varied for the different traits.…”

“…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).…”

Combining ability, heterosis, genetic distance and their intercorrelations for waterlogging tolerance traits in chrysanthemum

“…Betrán et al (2003) reported a highly significant correlation between GD and SCA effects (r = 0.8) in maize under stress and non-stress conditions. Devi and Singh (2011) demonstrated that SCA could emerge as an important factor in the determination of heterosis and per se performance of the hybrids. However, Ceballos et al (2016) observed weak associations between the GD and SCA effects, which presented r 2 values ranging from 0.00 to 0.28.…”

Determining behaviour of maize genotypes and growing environments using AMMI statistics

“…Inbred parents performance, combining ability and genetic diversity among them are considered to be important factors determining success of single cross hybrid development programme (Devi and Singh, 2011). Due to involvement of only two parents, the adaptability of single cross hybrids to the existing environmental conditions due to global climate change has been questioned.…”