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 QTL and also for studying heterosis. In this study, we first develop a multiple interval mapping model (MIM) f...

BACKGROUND Hybrids represent a cornerstone in the success story of breeding programs. The fundamental principle underlying this success is the phenomenon of hybrid vigour, or heterosis. It describes an advantage of the offspring as compared to the two parental lines with respect to parameters such as growth and resistance against abiotic or biotic stress. Dominance, overdominance or epistasis b...

Three strains of brook trout Salvelinus fontinalis (domestic [D], Laval [L], and Rupert [R]) and their reciprocal hybrids were reared from 7 to 21 months of age in three different environments (indoor, constant temperature conditions; indoor, seasonal temperature variations; and outdoor, seasonal temperature variations) to test for the occurrence of heterosis in important life history traits of...

Cotton is one of the most important commercial crops in India, playing a key role in national economy. Short duration and high yielding varieties are always required for better quality and lint production. Early maturing crops avoid disease and pest epidemics due to which plant breeders have positioned adequate pressure on the development of early maturing crop plants (Singh, 2004). Term earlin...

The objective of the present study was to correlate the genetic distances (GD) of single cross hybrids with yield, heterosis and specific combining ability (SCA) in the double cross hybrid synthesis. For this, 10 single cross commercial hybrids were used from different companies, and all the possible double hybrids were synthesized by a complete dialell. The hybrids were assessed in 15 location...

Biological invasions are often associated with multiple introductions and genetic admixture of previously isolated populations. In addition to enhanced evolutionary potential through increased genetic variation, admixed genotypes may benefit from heterosis, which could contribute to their increased performance and invasiveness. To deepen our understanding of the mechanisms and management strate...

European water frog hybrids Rana esculenta (Rana ridibunda x Rana lessonae) reproduce hemiclonally, transmitting only their ridibunda genome to gametes. We compared fitness-related larval life-history traits of natural R. esculenta from Poland with those of the two sympatric parental species and of newly generated F1 hybrids. Compared with either parental species, F1 hybrid offspring had higher...

Heterosis is widely used in breeding, but the genetic basis of this biological phenomenon has not been elucidated. We postulate that additive and dominance genetic effects as well as two-locus interactions estimated in classical QTL analyses are not sufficient for quantifying the contributions of QTL to heterosis. A general theoretical framework for determining the contributions of different ty...

HE phenomenon of heterosis has generally been studied in relation to some Tarbitrarily selected trait such as size, weight, or yield. Heterosis is then regarded as being manifested by an increase in the chosen trait. Although various definitions have been proposed ( GOWEN 1952), heterosis is most commonly and most meaningfully defined as an increase in the chosen trait in crossbred individuals ...