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A key aspect of selective breeding programs is whether the traits of interest respond similarly in different environments. The magnitude of the genotype by environment (G × E) interaction and heritability are responsible for this aspect. Commercial hatcheries in northern China supply batches of seed to oyster farmers each year, which are cultivated in a wide range of growing sites. However, the extent to which G × E interactions affect the ability to identify quality oyster lines has not been measured. Therefore, the objective of this study was to estimate the genetic parameters and G × E interactions for harvest traits in C. gigas cultured in northern China. Oysters from 40 mostly full-sib families (the offspring of 36 sires and 40 dams) were tested at three major commercial cultivation sites: Rushan, Hungdao and Rongchceng. We recorded shell height (SH), shell length (SL), shell width (SW), individual weight (IW), survival rate (SR), wet meat weight (WMW), meat ratio (MR) and shell shape (SS) at harvest. Compared with control line, selected line exhibited high superiority in survival rate at three sites. Heritability estimates for the harvest traits were low to high across different sites (0.55–0.75 for SH, 0.25–0.49 for SL, 0.20–0.33 for SW, 0.37–0.71 for IW, 0.10–0.12 for SR, 0.40–0.52 for WMW, 0.14–0.34 for MR and 0.18–0.30 for SS). Genetic correlations among growth traits were medium to high and positive, ranging between 0.52 ± 0.15 (between SH and SW at Huangdao) to 0.90 ± 0.04 (between SH and IW at Rongcheng). Nevertheless, we found significantly negative genetic correlations between growth traits and shell shape, an index that takes into account growth traits and shell shape should be developed to improve both simultaneously. Since it is not possible to disentangle this result from the correlation that mathematically determined alone, this result requires further study. Notably, genetic correlations between growth traits and survival were low, ranging from − 0.31 ± 0.17 (between SL and SS at Huangdao) to 0.14 ± 0.19 (between SW and SS at Rongcheng). G × E interactions were estimated as genetic correlations between the same trait measured on different oysters at three sites. Moderate G × E interactions were found for growth traits (0.45–0.87), meat yield traits (0.40–0.73) and shell shape (0.22–0.69), and weak G × E interaction was found for survival at harvest (0.80–0.86). This study reveals the presence of weak to high re-ranking of genotypes for harvest traits in C. gigas cultured in different commercial sites, suggesting that G × E interactions should be considered in oyster breeding program servicing multiple sites. [ABSTRACT FROM AUTHOR]

Abstract: The domestication of crops in the Fertile Crescent began approximately 10,000 years ago indicating a change from a hunter‐gatherer lifestyle to a sedentary, agriculture‐based existence. The exploitation of wild plants changed during this transition, such that a small number of crops were domesticated from the broader range of species gathered from the wild. However, the reasons for this change are unclear. Previous studies have shown unexpectedly that crop progenitors are not consistently higher yielding than related wild grass species, when growing without competition. In this study, we replicate more closely natural competition within wild stands, using two greenhouse experiments to investigate whether cereal progenitors exhibit a greater seed yield per unit area than related wild species that were not domesticated. Stands of cereal progenitors do not provide a greater total seed yield per unit ground area than related wild species, but these crop progenitors do have greater reproductive efficiency than closely related wild species, with nearly twice the harvest index (the ratio of harvested seeds to total shoot dry mass). These differences arise because the progenitors have greater seed yield per tiller than closely related wild species, due to larger individual seed size but no reduction in seed number per tiller. The harvest characteristics of cereal progenitors may have made them a more attractive prospect than closely related wild species for the early cultivators who first planted these species, or could suggest an ecological filtering mechanism. Synthesis. Overall, we show that the maintenance of a high harvest index under competition, the packaging of seed in large tillers, and large seeds, consistently distinguish crop progenitors from closely related wild grass species. However, the archaeological significance of these findings remains unclear, since a number of more distantly related species, including wild oats, have an equally high or higher harvest index and yield than some of the progenitor species. Domestication of the earliest cereal crops from the pool of wild species available cannot therefore be explained solely by species differences in yield and harvest characteristics, and must also consider other plant traits. [ABSTRACT FROM AUTHOR]

During the origin of agriculture in the Fertile Crescent, the broad spectrum of wild plant species exploited by hunter-gatherers narrowed dramatically. The mechanisms responsible for this specialization and the associated domestication of plants are intensely debated. We investigated why some species were domesticated rather than others, and which traits they shared., We tested whether the progenitors of cereal and pulse crops, grown individually, produced a higher yield and less chaff than other wild grasses and legumes, thereby maximizing the return per seed planted and minimizing processing time. We compared harvest traits of species originating from the Fertile Crescent, including those for which there is archaeological evidence of deliberate collection., Unexpectedly, wild crop progenitors in both families had neither higher grain yield nor, in grasses, less chaff, although they did have larger seeds. Moreover, small-seeded grasses actually returned a higher yield relative to the mass of seeds sown. However, cereal progenitors had threefold fewer seeds per plant, representing a major difference in how seeds are packaged on plants., These data suggest that there was no intrinsic yield advantage to adopting large-seeded progenitor species as crops. Explaining why Neolithic agriculture was founded on these species, therefore, remains an important unresolved challenge. [ABSTRACT FROM AUTHOR]

Genetic variation in performance and quality traits measured at harvest has previously been demonstrated in Atlantic salmon aquaculture populations. To map major loci underlying this variation, we utilized data from 10 families from a commercial breeding programme. Significant QTL were detected affecting harvest weight and length traits on linkage group 1, and affecting waste weight on linkage group 5. In total, 11 of the 29 linkage groups examined showed at least suggestive evidence for a QTL. These data suggest that major loci affecting economically important harvest characteristics are segregating in commercial salmon populations. [ABSTRACT FROM AUTHOR]