【摘要】Background: Gossypium arboreum is a diploid species cultivated in the Old World. It possesses favorable characters that are valuable for developing superior cotton cultivars. Method: A set of 197 Gossypium arboreum accessions were genotyped using 80 genome-wide SSR markers to establish patterns of the genetic diversity and population structure. These accessions were collected from three major G. arboreum growing areas in China. A total of 255 alleles across 80 markers were identified in the genetic diversity analysis. Results: Three subgroups were found using the population structure analysis, corresponding to the Yangtze River Valley, North China, and Southwest China zones of G.arboreum growing areas in China. Average genetic distance and Polymorphic information content value of G. arboreum population were 0.34 and 0.47, respectively, indicating high genetic diversity in the G. arboreum germplasm pool. The Phylogenetic analysis results concurred with the subgroups identified by Structure analysis with a few exceptions. Variations among and within three groups were observed to be 13.61% and 86.39%, respectively. Conclusion: The information regarding genetic diversity and population structure from this study is useful for genetic and genomic analysis and systematic utilization of economically important traits in G. arboreum.
《棉花研究（英文）》 | 2018年3期 | JIA Yinhua
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【摘要】[Objective] The paper was to clarify the sensitivity and resistance of Pseudoperonospora cubensis to cymoxanil. [Method] A total of 69 strains were collected from 13 major cucumber producing areas in eight provinces and cities of Guangdong, Hubei, Jiangsu, Shandong, Beijing, Liaoning, Jilin and Heilongjiang from 2012 to 2016, and their sensitivity and resistance to cymoxanil was determined using leaf disc floating method. [Result] The EC50 of cymoxanil to P. cubensis were 0.006 8-0.134 1 （xg/mL and the average EC50 was 0.062 4（xg/mL. The sensitivity of P. cubensis to cymoxanil presented a single-peak curve, which was approximately normal distribution, and no strains with decreased sensitivity were found. The average EC50 (0.062 4（xg/mL) could be used as the sensitivity baseline of P. cubensis to cymoxanil. Among the 69 strains, 16 were low-resistance strains, accounting for 23.19% of the total strains; 53 were sensitive strains, accounting for 76.81%, which were dominant populations; and no medium-resistance and high resistance strains were found. The resistance of P. cubensis to cymoxanil ranged from 0.11 to 2.15 times, and the average resistant level was 1.00 times. [Conclusion] Cymoxanil showed strong inhibitory effect against P. cubensis.
《Plant Diseases and Pests》 | 2019年3期 | Zhang Yanju
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【摘要】Antimicrobial resistance is an urgent global health challenge in human and veterinary medicine. Wild animals are not directly exposed to clinically relevant antibiotics; however, antibacterial resistance in wild animals has been increasingly reported worldwide in parallel to the situation in human and veterinary medicine. This underlies the complexity of bacterial resistance in wild animals and the possible interspecies transmission between humans, domestic animals, the environment, and wildlife. This review summarizes the current data on expanded- spectrum p-lactamase (ESBL), AmpC p-lactamase, carbapenemase, and colistin resistance genes in Enterobacteriaceae isolates of wildlife origin. The aim of this review is to better understand the important role of wild animals as reservoirs and vectors in the global dissemination of crucial clinical antibacterial resistance. In this regard, continued surveillance is urgently needed worldwide.
《动物学研究》 | 2017年2期 | Jing Wang
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【摘要】<p>The United States is a country of immigrants with</p><p>more than 100 other ethnic peoples，thus forming its own immigrant</p><p>culture. However，during this process of integration，each ethnic</p><p>group has kept its own ethnicity and culture while cultivating a</p><p>mixed culture called American culture. From the perspective of</p><p>inclusiveness and integration of immigrant culture，the United States</p><p>is like a melting pot in some ways and a mosaic in other ways. This</p><p>paper tries to analyze the process of integrating and disintegrating</p><p>and its significance in the age of globalization</p><p><br/></p>
《东方教育》 | 2015年22期 | 刘 晴
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【摘要】Soybean cyst nematode (SCN), Heterodera glycine, is one of the important diseases affecting the yield of soybean (Glycine max} worldwide. Host-plant resistance is the most economically effective way to control SCN. Identification of DNA markers linked to SCN resistance genes is one of the important steps in the marker-assisted selection (MAS) for nematode resistance breeding. Quantitative trait loci (QTLs) controlled by multiple resistance genes plays a powerful role in MAS-breeding program. In this paper, we reviewed genetic resistance of SCN, molecular markers of resistance gene and Genome-Wide Associated Study (GWAS) of QTLs linked to SCN resistance, explored the present problems of genetic resistance, and prospected the future of QTL analysis.
《Plant Diseases and Pests》 | 2019年1期 | Wang Gongli
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【摘要】Small populations with low genetic diversity areprone to extinction. Knowledge on the geneticdiversity and structure of small populations and theirgenetic response to anthropogenic effects are ofcritical importance for conservation management. Inthis study, samples of Ancherythroculter nigrocauda,an endemic cyprinid fish from the upper reaches ofYangtze River, were collected from five sites toanalyze their genetic diversity and populationstructure using mitochondrial cytochrome b geneand 14 microsatellite loci. Haplotype diversity,nucleotide diversity, and expected heterozygosityindicated that the A. nigrocauda populations had lowgenetic diversity, and decreased heavily from 2001to 2016. Significant genetic differentiation was foundamong different populations in the cyt b gene andSSR markers based on the genetic differentiationindex （FST）， whereas no differentiation was found in2001. Haplotype genealogy showed that eight out of15 haplotypes were private to one population. TheSSR STRUCTURE analysis showed that there werefour genetic clusters in the A. nigrocauda samples,with each population forming a single cluster, exceptfor the Chishui River （CSR） and Mudong River（MDR） populations, which formed a common cluster. Therefore, loss of genetic diversity and increasedgenetic differentiation were found in the A. nigrocauda populations, which could be attributed todam construction, overfishing, and water pollution inthe upper Yangtze River. It is therefore recommended that the government should ban fishing, control water pollution, increase riverconnectivity, and establish artificial breeding andstocking.
《动物学研究》 | 2019年5期 | Dong-Dong Zhai1
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【摘要】<p>In the traditional teaching，English teaching is affected by</p><p>examination-oriented education ideas ， classroom teaching is used of</p><p>non-computer majors and cramming methods.Adjust the emotion and</p><p>strategy during the learning process，to form a positive learning attitude and</p><p>improve language practical application ability.Cooperative learning is based</p><p>on the requirement of new curriculum reform to arise at the historic</p><p>moment of new classroom teaching mode.</p><p><br/></p>
《东方教育》 | 2015年6期 | 彭 欣
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【摘要】<p>Transformation from planned economy system to market economy system is not only the</p><p>reason for the success of Reform and Opening-up in China, itself is also the most important results.</p><p>However, "planning" has been a basic feature of higher education system during more than 30 years</p><p>since the Reform and Opening-up. Planned education system has become an integral part of the political</p><p>system in our country, owing to the consistency of the education system and the national system.</p><p>Dominated by political and administrative power, planned education system is essentially anti-competitive,</p><p>but in the meantime the abnormal competition under the planned education system is fierce for some</p><p>institutional reasons. Indeed, the competition is often not the spontaneous result of higher education or</p><p>university, but guided by some government calls and aims at being brought into the educational plan.</p><p><br/></p>
《大学教育科学》 | 2016年6期 | WANG Jian-hua
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