In order to better promote the development of grassland husbandry in the Bijie experimental area and promote industrial poverty alleviation and rural revitalization strategies,the development status of grassland agric...In order to better promote the development of grassland husbandry in the Bijie experimental area and promote industrial poverty alleviation and rural revitalization strategies,the development status of grassland agriculture in developed countries( USA,Netherlands and France) and China is summarized. By learning from the successful experience of grassland agricultural development at home and abroad,combined with the survey results of grassland agriculture in Dafang County of Bijie experimental area,the development of grassland agriculture in Dafang County of Bijie experimental area is analyzed,and corresponding development strategies are put forward.展开更多
Many paleognaths(ratites and tinamous) have a pair of homomorphic ZW sex chromosomes in contrast to the highly differentiated sex chromosomes of most other birds. To understand the evolutionary causes for the differen...Many paleognaths(ratites and tinamous) have a pair of homomorphic ZW sex chromosomes in contrast to the highly differentiated sex chromosomes of most other birds. To understand the evolutionary causes for the different tempos of sex chromosome evolution, we produced female genomes of 12 paleognathous species and reconstructed the phylogeny and the evolutionary history of paleognathous sex chromosomes.We uncovered that Palaeognathae sex chromosomes had undergone stepwise recombination suppression and formed a pattern of “evolutionary strata”. Nine of the 15 studied species’ sex chromosomes have maintained homologous recombination in their long pseudoautosomal regions extending more than half of the entire chromosome length. We found that in the older strata, the W chromosome suffered more serious functional gene loss. Their homologous Z-linked regions, compared with other genomic regions, have produced an excess of species-specific autosomal duplicated genes that evolved female-specific expression, in contrast to their broadly expressed progenitors. We speculate such “defeminization” of Z chromosome with underrepresentation of female-biased genes and slow divergence of sex chromosomes of paleognaths might be related to their distinctive mode of sexual selection targeting females rather than males, which evolved in their common ancestors.展开更多
基金Supported by Science and Technology Innovation Project of Guizhou Academy of Agricultural Sciences(Qian Nong Ke Yuan Ke Ji Chuang Xin(2017)01)Key Research Topic of Bijie City(BSDY-1083)Science and Technology Achievements Transformation Project of Guizhou Province(Qian Ke He Cheng Guo(2019)4209)
文摘In order to better promote the development of grassland husbandry in the Bijie experimental area and promote industrial poverty alleviation and rural revitalization strategies,the development status of grassland agriculture in developed countries( USA,Netherlands and France) and China is summarized. By learning from the successful experience of grassland agricultural development at home and abroad,combined with the survey results of grassland agriculture in Dafang County of Bijie experimental area,the development of grassland agriculture in Dafang County of Bijie experimental area is analyzed,and corresponding development strategies are put forward.
基金supported by the National Natural Science Foundation of China (32061130208, 32170415)the Natural Science Foundation of Zhejiang Province (LD19C190001)+4 种基金the European Research Council Starting Grant (grant agreement 677696)supported by Strategic Priority Research Program of the Chinese Academy of Sciences (XDB31020000, XDB13000000)International Partnership Program of Chinese Academy of Sciences (152453KYSB20170002)Carlsberg foundation (CF16-0663)Villum Foundation (25900)。
文摘Many paleognaths(ratites and tinamous) have a pair of homomorphic ZW sex chromosomes in contrast to the highly differentiated sex chromosomes of most other birds. To understand the evolutionary causes for the different tempos of sex chromosome evolution, we produced female genomes of 12 paleognathous species and reconstructed the phylogeny and the evolutionary history of paleognathous sex chromosomes.We uncovered that Palaeognathae sex chromosomes had undergone stepwise recombination suppression and formed a pattern of “evolutionary strata”. Nine of the 15 studied species’ sex chromosomes have maintained homologous recombination in their long pseudoautosomal regions extending more than half of the entire chromosome length. We found that in the older strata, the W chromosome suffered more serious functional gene loss. Their homologous Z-linked regions, compared with other genomic regions, have produced an excess of species-specific autosomal duplicated genes that evolved female-specific expression, in contrast to their broadly expressed progenitors. We speculate such “defeminization” of Z chromosome with underrepresentation of female-biased genes and slow divergence of sex chromosomes of paleognaths might be related to their distinctive mode of sexual selection targeting females rather than males, which evolved in their common ancestors.
