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The Betta fish displays a remarkable variety of phenotypes selected during domestication. However, the genetic basis underlying these traits remains largely unexplored. Here, we report a high-quality genome assembly and resequencing of 727 individuals representing diverse morphotypes of the Betta fish. We show that current breeds have a complex domestication history with extensive introgression with wild species. Using a genome-wide association study, we identify the genetic basis of multiple traits, including coloration patterns, the "Dumbo" phenotype with pectoral fin outgrowth, extraordinary enlargement of body size that we map to a major locus on chromosome 8, the sex determination locus that we map to

The Betta fish displays a remarkable variety of phenotypes selected during domestication. However, the genetic basis underlying these traits remains largely unexplored. Here, we report a high-quality genome assembly and resequencing of 727 individuals representing diverse morphotypes of the Betta fish. We show that current breeds have a complex domestication history with extensive introgression with wild species. Using a genome-wide association study, we identify the genetic basis of multiple traits, including coloration patterns, the “Dumbo” phenotype with pectoral fin outgrowth, extraordinary enlargement of body size that we map to a major locus on chromosome 8, the sex determination locus that we map to dmrt1 , and the long-fin phenotype that maps to the locus containing kcnj15 . We also identify a polygenic signal related to aggression, involving multiple neural system-related genes such as esyt2 , apbb2 , and pank2 . Our study provides a resource for developing the Betta fish as a genetic model for morphological and behavioral research in vertebrates.

In this study, soil and rice samples from 85 sites in six cities in Hunan Province were analyzed for Cu, Zn, Pb, Cd, Hg, Mn, and Co (total and bioavailable concentrations for soil) in July 2014. The results indicated that the total concentrations of Cu, Zn, Pb, Cd, and Hg in soil had increased significantly compared with the 1980s, and were correlated with their bioavailable concentrations in soil positively. The total concentrations of Cd and Co in soil were correlated with those in rice. Bioavailable concentrations of Cd, Mn, Co, Pb, and Cu represented 64.4%, 33.2%, 12.0%, 11.6%, and 6.1% of the total soil concentrations, respectively. The bioavailable concentrations of Cd and Co in soil had a extremely significant (p &lt, 0.01) positive correlation with those in rice, suggesting that bioavailable concentrations was a better indicator for soil potentially toxic elements contamination. The pH values had a significant influence on the bioavailability of Cd and Cu and the amounts taken up by rice. The Cd contamination in 27.0% rice samples exceeded World Health Organization recommended thresholds. The results added basic pollution distribution data, further revealing the relationships of metals in soil and crops and would offer great help to the metallic pollution control in these areas.

The concentrations, chemical availability, distribution, and sources of potentially toxic elements (PTEs) in the soil of Xiangjiang Basin in Hunan Province, China were investigated at 85 sites. The highest mean concentrations of Cd, Cu, Zn, As, and Pb were observed in Hengyang, whereas those for Mn, Co, and Hg were observed in Changde. The pollution index values followed the order: Cd &gt, Hg &gt, Cu &gt, Zn &gt, As &gt, Pb, the mean geo-accumulation index values were in the order: Cd &gt, Pb &gt, Co &gt, Mn. Cd was associated with moderate contaminated level, Hg and Pb were associated with moderate contaminated to uncontaminated level, and Cu, Zn, As, Co, and Mn were associated with uncontaminated level of pollution. Furthermore, 64.5% of Cd was water-soluble and exhibited exchangeable fractions, its chemical availability posed a risk to the ecosystem. Spatial analysis, principal component analysis, and a positive matrix factorization model were used to assess the PTE sources. Four principal components contributed to 88.8% of the 8 PTEs concentrations. Mining, smelting, industrial, and agricultural activities, alongside sewage irrigation, the use of agrochemicals, and vehicular emissions are the possible anthropogenic sources that pollute agricultural products and threaten human health in the Xiangjiang Basin.

Intestinal microbiota plays crucial roles in host health. Unlike oxidized fish oil, taurine supplementation shows positive effects on intestinal health, whereas their impacts on intestinal microbiota remain unclear. Therefore, our goal of the present study was to understand the homeostasis mechanism and function of intestinal microbiota in rice field eel (Monopterus albus) fed with 5 experimental diets including basal diet (Control group), diets containing 100 (POV100 group) and 600 (POV600 group) meq/kg oxidized fish oil, and 600 meq/kg diet with supplementation of 0.1% (Ta1 group) and 0.2% (Ta2 group) taurine, respectively. Our results suggested that Clostridia, Fusobacteriia, and Gammaproteobacteria were three predominant microflora in the gut of eels. However, oxidized fish oil diet decreased the number of species and species richness together with a reduction in intestinal microbial diversity, and reduced the relative abundance of Clostridia caused by a significant increase in Fusobacteriia (classified as Cetobacterium). Nevertheless, 600 meq/kg oxidized fish oil diet with supplementation of taurine could reinstate the number of species and species richness, and the microbial diversity become higher compared to Control group. Oxidized fish oil induced microbial dysbiosis through the restriction of ecological network by declining the average connectivity and the total number of generalists, whereas taurine supplementation could reduce the negative impacts of oxidized fish oil and maintain the stability of intestinal microbiota. Furthermore, the increasing level of oxidized fish oil intensified the difference in microbial function from that in Control group, whereas 0.2% taurine supplementation restored its function to a similar level as that in Control group. These results suggested that the oxidized fish oil diet could disturb the stability of microbial community and cause microbial dysfunctions, whereas taurine supplementation helped the intestinal microbiota homeostasis and restored its function.

Long-term records are essential for evaluating recent glacier fluctuation and its linkage to climate change. Moraines of two glaciers (Gawalong glacier and Xincuo glacier) in the southeastern Tibetan Plateau were dated. Germination date of the oldest tree yields a minimum age before 1760s for the outermost lateral moraine of Gawalong glacier in southern Bomi. A tilted tree indicated that the glacier readvanced to its maximum position since the early 20th century at around 1987e1992. Xincuo glacier in eastern Gongbujiangda reached its Little Ice Age (LIA) maximum before 1876. The difference implies that detailed dating of moraines is necessary for studying LIA glacier response to climate change in the study area. Trees growing on LIA glacier deposits proved to be very useful for deriving age estimates of historic glacier fluctuations in the southeastern Tibetan Plateau.