The present investigation was conducted to assess the magnitude of heterosis rabi sorghum (Sorghum bicolor (L.) Moench) developed by crossing four lines and twelve testers (in a line × tester design) produce 48 F1 cross combinations at Sorghum Improvement Project, MPKV., Rahuri, Maharashtra. To identify high-yielding Rabi hybrids, promising hybrids were sorted out based on positive significant ...

Inbreeding avoidance is often invoked to explain observed patterns of dispersal, and theoretical models indeed point to a possibly important role. However, while inbreeding load is usually assumed constant in these models, it is actually bound to vary dynamically under the combined influences of mutation, drift, and selection and thus to evolve jointly with dispersal. Here we report the results...

Work from the 1970s indicated that, relative to either parent species, crosses between red spruce (Picea rubens Sarg.) and black spruce (Picea mariana (Mill.) B.S.P.) were inferior with respect to both growth and photosynthesis. We re-examined the hypothesis that there is negative heterosis in hybrids of red and black spruce using 22-year-old trees in a common garden study planted on two sites....

Monthly weights, heights and condition scores and measurements taken at the time of puberty were utilized to estimate effects of breed-type and heterosis on characters related to growth, size and puberty of second-generation heifers of a five-breed diallel involving Angus, Brahman, Hereford, Holstein and Jersey. One group of heifers was maintained on pasture with supplemental feed; two other gr...

Altering gene dosage through variation in gene copy number is a powerful approach to addressing questions regarding gene regulation, quantitative trait loci, and heterosis, but one that is not easily applied to sexually transmitted species. Elite poplar (Populus spp) varieties are created through interspecific hybridization, followed by clonal propagation. Altered gene dosage relationships are ...

The success of vector control strategies aiming to decrease disease transmission via the release of sterile or genetically-modified male mosquitoes critically depends on mating between laboratory-reared males and wild females. Unfortunately, mosquito colonization, laboratory rearing, and genetic manipulations can all negatively affect male competitiveness. Heterosis is commonly used to produce ...

Italian ryegrass is one of the most important temperate forage grasses on a global basis. Improvement of both dry matter yield and quality of herbage have been major objectives of pasture grass breeding over the last century. F1 and F2 progeny sets derived from controlled pair-crosses between selected Italian ryegrass genotypes have been evaluated for yield and nutritive quality under field con...

number of studies have shown that the manifestation of heterosis may be A dependent on physical and biotic environments. DOBZHANSKY et al. (1955) found that Drosophila pseudoobscura heterozygous for genes on the second chromosome was, in general, superior to homozygotes in viability. The relative viabilities of homozygotes and heterozygotes changed, however, with varying temperatures and with d...

the diallel cross design is frequently utilized to obtain information on genetic effects, estimates of general and specific combining ability (gca and sca) and to identify promising heterotic combinations as well as heterotic patterns. in the present study, heterotic crosses were identified for specific alkaloids in opium poppy (papaver somniferum l.) following yan’s gge biplot model by use of ...

Quality, quantity, and cost of feed resources available for beef production vary from one region of the country to another and within regions, depending upon climatic factors and natural resources available in specific production situations. Diversity among breeds can be exploited by crossbreeding to optimize performance levels and to match genetic resources with the climatic environment, feed ...