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31.
畜牧养殖业污染问题是畜牧养殖生产过程中的常见问题,对于养殖业也有一定的影响,直接影响畜牧产品质量及动物疫病防治工作。该文针对畜牧养殖业污染现状进行分析研究,阐述畜牧养殖污染问题现状,并综合新疆地区的畜牧养殖业发展状态,提出畜牧养殖污染问题综合治理的有效对策。  相似文献   
32.
为保护右江流域生态环境,协调郁江乃至珠江上下游各方经济利益,更好的激励上游地区生态环境保护行为,通过分析右江流域水生态现状、存在问题、现有生态补偿政策环境及其在郁江流域、珠江流域中的地位和作用,利用外部性理论,分析提出了右江流域水生态补偿模式。通过对标对表有关生态保护规划和区划成果,立足百色市实际,提出了右江流域水生态补偿内容、补偿主客体、补偿标准和补偿方式,初步构建右江流域水生态补偿机制框架,并提出有针对性的补偿政策建议,为水生态补偿实施提供了参考。  相似文献   
33.
为了建立青蒿的SRAP最佳扩增体系,并筛选出SRAP多态性引物,本研究以青蒿叶片DNA为模板,采用正交试验设计,以Mg^2+、dNTP Mix、Taq DNA聚合酶、引物和DNA模板5种因素5个水平,对青蒿SRAP反应体系进行研究。结果表明,青蒿SRAP-PCR最佳反应体系为:引物0.6μmol/L、Mg^2+2.0 mmol/L、模板DNA 5.1 ng、Taq DNA聚合酶2.0 U、dNTPs 0.25 mmol/L,总体积为25μL。各因素对扩增反应均有不同影响,其中引物浓度的影响最大,dNTPs的影响最小。运用该体系对不同种质资源的青蒿进行验证,证明该体系稳定可靠,并在30个引物组合中筛选出了25对扩增条带清晰,多态性丰富的引物组合。这一结论为今后利用SRAP标记技术进行青蒿分子遗传学研究提供了科学依据。  相似文献   
34.
35.
To investigate the epizootic of swine influenza virus(SIV), 60 nasal swabs were collected from a clinical cases of pig farm in Tai'an City, Shandong Province of China in April 2017. SIV was isolated by inoculating into 10-day-old Special Pathogen Free embryonated eggs and the whole genome was sequenced. An H1N1 subtype SIV was isolated and designated as A/swine/Shandong/TA04/2017(H1N1). Phylogenetic analysis showed that apart from the polymerase A(PA) fragment belonging to the 2009 pandemic H1N1 branch, seven genome segments belonged to avian-like H1N1 influenza virus lineage. The cleavage site sequence of the hemagglutinin(HA) protein was PSIQSR↓G, which is a typical molecular biological characteristic. Five potential N-glycosylation sites(N14, N26, N277, N484 and N543) were found in the HA gene. To further investigate the epidemiology of SIV in this farm, the 995 serum samples were assessed with EAH1N1 2009 pandemic H1N1 and H3 N2 antigens. The results showed that the total positive rate was 65.43%. The positive rates of single virus infection detected by EAH1N1, 2009 pdmH1N1 and H3 N2 for serum HI(Hemagglutination inhibition) were 48.35, 30.85 and 7.47%, respectively. The results showed that SIV in Shandong Province has been reassorted in some segments and the SIV-positive rate was high on the SIV outbreak farm. These data provide evidence of an epizootic of SIV.  相似文献   
36.
Four sets of durum samples were used in this study to further understand the interrelationships among hard vitreous kernels (HVK), protein content, and pigment concentration, with a focus on the interaction and synergistic effects of protein content and vitreousness on durum quality. HVK level increases with higher protein content in the range of 9.5–12.5%, but this relationship is less evident in durum samples with high protein content (12.5–14.5%). Both protein content and kernel vitreousness can significantly affect durum milling quality. White starchy kernels (WSK) in low protein durum have a very detrimental impact on milling and pasta processing quality, but high protein content can mitigate the adverse impact of WSK on durum quality. Although protein content plays a dominant role, higher HVK might contribute positively to pasta firmness. There was no significant difference in yellow pigment content between HVK and WSK. However, pigment loss from semolina to dough was higher for WSK than HVK. Despite the difference in protein content, HVK and WSK have little difference in gluten strength. The monomeric protein was preferentially accumulated in HVK. The glutenin proteins of HVK and WSK were similar in the ratios of 1Bx/1By and HMW/LMW-GS.  相似文献   
37.
Single‐nucleotide polymorphisms (SNPs) are rapid, economical and reliable genotyping tools. Non‐heading Chinese cabbage (Brassica rapa L. subsp. chinensis Makino) is now an economically important vegetable crop worldwide. In this study, 1,167 SNPs were evaluated for 7polymorphism among 70 representative non‐heading Chinese cabbage inbred lines using a Kompetitive Allele Specific PCR (KASP) genotyping assay. On the basis of identified polymorphisms and the results of a principal component analysis, we selected 50 core SNPs that were balanced sufficiently to provide adequate information for genetic identification. The core SNPs were used for construction of a neighbour‐joining dendrogram that separated the 70 inbred lines into four main groups and several subgroups corresponding to Caixin, Heiyebaicai, Huangxinwu, Naibaicai, Taitsai, Pak‐choi, and Wutatsai. This categorization was superior to that achieved using a dataset of 479 polymorphic SNPs. To confirm the utility of the core SNP markers in genetic identification, we tested their stability and resolution using 162 commercial hybrid cultivars. The SNPs, which represent a cost‐effective, accurate marker set for germplasm analysis and cultivar identification, are suitable for molecular marker‐assisted breeding in non‐heading Chinese cabbage.  相似文献   
38.
Rice production needs to increase in the future in order to meet increasing demands. The development of new improved and higher yielding varieties more quickly will be needed to meet this demand. However, most rice breeding programmes in the world have not changed in several decades. In this article, we revisit the evidence in favour of using rapid generation advance (RGA) as a routine breeding method. We describe preliminary activities at the International Rice Research Institute (IRRI) to re-establish RGA on a large scale as the main breeding method for irrigated rice breeding. We also describe experiences from the early adoption at the Bangladesh Rice Research Institute. Evaluation of RGA breeding lines at IRRI for yield, flowering time and plant height indicated transgressive segregation for all traits. Some RGA lines were also higher yielding than the check varieties. The cost advantages of using RGA compared to the pedigree method were also empirically determined by performing an economic analysis. This indicated that RGA is several times more cost effective and advantages will be realized after 1 year even if facilities need to be built. Based on our experience, and previous independent research empirically testing the RGA method in rice, we recommend that this method should be implemented for routine rice breeding in order to improve breeding efficiency.  相似文献   
39.
油菜菌核病是油菜上的重要病害之一,在四川局部地区油菜根肿病时有发生,严重威胁到油菜安全生产。以油菜菌核病和根肿病为防治对象,与华中农业大学合作,利用其筛选的有益生防菌,选择双低和高芥酸油菜品种国豪油8号和绵油309,对其种子进行包衣处理,分别在无和有根肿病史的水旱轮作地,开展田间试验。试验结果表明:有益生防菌包衣处理的菌核病发病率均低于没有包衣处理;包衣处理的不同品种产量均高于没有包衣处理,但品种间有差异;包衣处理过的高芥酸油菜品种绵油309的产量高于包衣处理过的双低油菜品种国豪油8号;在有根肿病史试验田种植的菌核病发病率低于无根肿病史试验田,产量高于无根肿病史试验田。包衣处理对油菜根肿病的防治效果不显著。  相似文献   
40.
脲酶抑制剂与硝化抑制剂对稻田土壤氮素转化的影响   总被引:10,自引:0,他引:10  
【目的】本研究旨在阐明脲酶抑制剂(urease inhibitor,UI)和硝化抑制剂(nitrification inhibitor,NI)对稻田土壤氮素转化的影响,探讨抑制剂提高稻谷产量以及氮肥利用率的机理。【方法】本试验设在我国南方红壤稻田,共5个处理:1)不施氮肥(CK);2)尿素(U);3)尿素+脲酶抑制剂(U+UI);4)尿素+硝化抑制剂(U+NI);5)尿素+脲酶抑制剂+硝化抑制剂(U+UI+NI);脲酶抑制剂采用N-丁基硫代磷酰三胺(NBPT),硝化抑制剂采用3,4-二甲基吡唑磷酸盐(DMPP)。在水稻分蘖期和孕穗期测定土壤脲酶活性、硝酸还原酶活性、土壤铵态氮含量、硝态氮含量以及微生物碳、氮的含量,分析NBPT与DMPP对水稻两个主要生育期土壤氮素供应的影响,比较各处理的产量以及氮肥利用率,通过逐步回归分析研究以上各指标对产量的影响,探明脲酶抑制剂NBPT与硝化抑制剂DMPP在稻田的增效机理。【结果】1)与单施尿素相比,添加NBPT以及NBPT与DMPP配施均显著提高稻谷产量与地上部氮素回收率,两个处理分别增产6.56%与8.24%,氮素回收率提高幅度为19.4%与23.7%。2)与单施尿素相比,添加NBPT以及NBPT与DMPP配施,显著降低水稻分蘖期的土壤脲酶活性和铵态氮含量,显著提高孕穗期的铵态氮含量,而对此时期的脲酶活性无显著影响,所有处理对两个时期的硝态氮含量、硝酸还原酶活性、微生物量碳、氮含量均无显著影响;因此,NBPT对于抑制脲酶活性以及提高铵态氮含量的作用主要在孕穗期之前,而单施DMPP没有显著效应。3)从各项土壤指标与水稻产量相关性的逐步回归分析结果来看,水稻分蘖期与孕穗期稻田土壤中铵态氮含量对水稻产量影响显著,而且孕穗期的影响大于分蘖期,其余指标则对产量无显著影响。【结论】脲酶抑制剂NBPT以及NBPT与硝化抑制剂DMPP配施显著提高孕穗期土壤中的铵态氮含量,显著提高稻谷产量以及地上部氮素回收率,证明了生产上氮肥后移的重要意义。  相似文献   
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