Combining ability, gene action and heterosis was studied for no. of days to 50% tasseling, no. of days to 50% silking, flag leaf area, plant height, no. of rows/ear, no. of grains/row, 300-grain weight and grain yield/plant in a Factorial Mating in Randomized Completely Randomized Design conducted separately in spring and autumn sowing dates, 2013 through hybridization between three parents of ...

Parental selection is crucial for hybrid breeding, but the methods available for such a selection are not very effective. In this study, a 6×6 incomplete diallel cross was designed using 12 rapeseed germplasms, and a total of 36 hybrids together with their parental lines were planted in 4 environments. Four yield-related traits and seed oil content (OC) were evaluated. Genetic distance (GD) was...

Randomized complete block design was used, with three replications. Heterosis for yield and fruit quality characteristics studied, expressed as Relative heterosis, heterobeltiosis Standard heterosis. It would be expected, according to the dominance model, that heterosis recorded after crossing recombinant lines, having only a small portion of recessive deleterious alleles, minimal. The results ...

Despite its importance to agriculture, the genetic basis of heterosis is still not well understood. The main competing hypotheses include dominance, overdominance, and epistasis. NC design III is an experimental design that has been used for estimating the average degree of dominance of quantitative trait loci (QTL) and also for studying heterosis. In this study, we first develop a multiple-int...

If genetic variation for fitness traits in natural populations ("standing" variation) is maintained by recurrent mutation, then quantitative-genetic properties of standing variation should resemble those of newly arisen mutations. One well-known property of standing variation for fitness traits is inbreeding depression, with its converse of heterosis or hybrid vigor. We measured heterosis for t...

An incomplete diallel cross study comprising of seven bread wheat (Triticum aestivum L.) cultivars was carried out with parents and F1 progeny to determine heterosis, combining ability, gene action, and correlations for plant height and its components. The results showed that heterosis and heterobeltiosis occurred in plant height, spike length, peduncle length, length of the second internode fr...

Primary causes of heterosis are still unknown. Our goal was to investigate the extent and underlying genetic causes of heterosis for five biomass-related traits in Arabidopsis thaliana. We (i) investigated the relative contribution of dominance and epistatic effects to heterosis in the hybrid C24 x Col-0 by generation means analysis and estimates of variance components based on a triple testcro...

Heterosis is defined as the increased vigour of hybrids in comparison to their parents. We investigated 24 F(1) hybrid lines of Arabidopsis thaliana generated by reciprocally crossing either C24 or Col with six other parental accessions (Can, Co, Cvi, Ler, Rsch, Te) that differ widely in their freezing tolerance. The crosses differed in the degree of heterosis for freezing tolerance, both in th...

Juvenile growth and bud set phenology were analyzed to study the biological basis of heterosis (hybrid vigor) in interspecific hybrids of Populus tremuloides Michx. (T) and P. tremula L. (Ta). Growth, measured as seedling volume index, was significantly higher for each of the two reciprocal interspecific crosses, T x Ta and Ta x T, than for the T x T intraspecific cross. Broad-sense heritabilit...