Heterosis , hybrid vigor, or outbreeding enhancement, is the improved or increased function of any biological quality in a hybrid offspring. The adjective derived from heterosis is heterotic. An offspring exhibits heterosis if its traits are enhanced as a result of mixing the genetic contributions of its parents. Biologi › Vitenskapsgrener i biologien › Evolusjonsbiologi Bufret Lignende 14.
Heterosis , innen dyre- og planteavl det fenomen at krysningsproduktene mellom to raser ofte vil være mer hardføre, kraftigere utviklet og vokse raskere enn foreldrerasene, trolig fordi de er heterozygote for mange arveanlegg. Generelt sett er slike krysninger bedre tilpasset et variabelt miljø.
Heterosis , also called hybrid vigour, the increase in such characteristics as size, growth rate, fertility, and yield of a hybrid organism over those of its parents. Plant and animal breeders exploit heterosis by mating two different pure-bred lines that have certain desirable traits. The first-generation offspring generally show, . It was immediately apparent that hybrids are more heterozygous than their parents. A decrease in the number of heterozygotes implied an increase in the number of homozygotes.
This immediately gave rise to two . It has been exploited in the production of various crops for many years, yet its genetic and molecular basis has remained obscure. In a massive-scale set of . The physiological vitality of an organism is evident in its speediness of growth, its height and general strength that is certainly allied with the amount of difference in the gametes by whose unification of the organism was formed.
Heterosis refers to the phenomenon that progeny of diverse varieties of a species or crosses between species exhibit greater biomass, speed of development, and fertility than both parents. Understanding the genetic bases underlying heterosis is a major issue in maize ( Zea mays L.). We extended the North Carolina design III (NCIII) by using three populations of recombinant inbred lines derived from three parental lines belonging to different heterotic pools, crossed with each parental line to obtain nine . Heterosis is frequently defined as the superiority of the Fhybrids over the mid- parent value (see Fig. H41). This definition expresses heterosis as Σdywhere d is the dominance effect at all loci.
Heterosis definition: a phenomenon resulting from hybridization, in which offspring display greater vigor,. Meaning, pronunciation, translations and examples. Definition of Heterosis : The superiority of Fhybrid over both its parents in terms of yield or some other characters or heterosis is increased vigours, growth, yield or function of a hybrid over the parents, resulting from crossing of genetically unlike organisms.
There are two main theories which have been used to explain the mechanism of heterosis. One is the dominance hypothesis and the second is overdominace hypothesis. The epistasis is also considered to be associated with heterosis. Thus, there are three possible genetic causes of heterosis viz. Inbreeding and Heterosis.
To accomplish the purpose of hybrid seed production two phe- nomena are inevitably . Define heterosis : the marked vigor or capacity for growth often exhibited by crossbred animals or plants —called also hybrid vigor. English dictionary definition of heterosis. Demin Institute of Developmental Biology Academy of Science Moscow, U. The term heterosis (or hybrid vigour) characterizes the increased ability or a hybrid as compared to the parental forms.
The term ability means the favourable changes in hybrid characters when . Rxiv – the preprint server for biology, operated by Cold Spring Harbor Laboratory, a research and educational institution. Quantitative genetics, therefore, plays a central .