基于S基因序列分析新型猪流行性腹泻病毒的遗传演化     

周昱行  胡承哲  周群  王何欣  董沙沙  刘娟  张丹丹  任玉鹏  张斌 《畜牧兽医学报》2020,51(1):109-119

最近，笔者实验室在青藏高原地区发现两种新亚型藏猪源猪流行性腹泻病毒（PEDV），为进一步调查新型PEDV是否在四川腹泻猪群中存在或流行，对实验室2018-2019年保存的116份猪腹泻粪便或肠组织样本进行PEDV的检测及其纤突蛋白基因（spike）分子特征研究。结果表明：腹泻样本的PEDV检出率为42.2%（49/116，95% CI=33.1%~51.8%），并获得了13条完整的S基因序列，全长为4 149~4 170 bp，序列相似性为94.2%~99.9%，其中SWUN-H3-CH-SCYA-2019的S基因与藏猪源新G1亚群PEDV的序列相似性高达97.0%~98.6%。遗传演化研究结果表明13株PEDV S基因划分为G1和G2大群，其中SWUN-H3-CH-SCYA-2019位于藏猪源新G1亚群；SWUN-19-CH-SCZY-2018、SWUN-4-CH-SCXC-2018、SWUN-1-CH-SCNJ-2019和SWUN-3CH-CH-SCZG-2019位于G2亚群中一个独立的分支，且与藏猪源新G2亚群毒株有着较近的亲缘关系。为了进一步研究13株PEDV的演化过程，以贝叶斯进化分析软件包（BEAST）进行分歧时间估算，结果表明SWUN-H3-CH-SCYA-2019的分歧时间约为2012.3年，早于藏猪源新G1亚群其余毒株的最早分歧时间（2015.7年）；SWUN-4-CH-SCXC-2018、SWUN-19-CH-SCZY-2018和SWUN-3CH-CH-SCZG-2019的分歧时间约为2014.2年，早于G2亚群的藏猪源毒株2014.7年，所有藏猪源PEDV的分歧时间均晚于四川毒株。本研究在四川地区首次发现了藏猪源PEDV，并且从毒株的分歧时间推断青藏高原的藏猪源PEDV来源于四川，为新型PEDV分子遗传进化的监测提供了依据。  相似文献   

基于B/S的农业气象自动化观测系统国家级平台设计与应用     

沈超 《现代农业科技》2019,(20)

农业气象自动化观测系统国家级平台是依托中国气象局组织的农业气象自动化观测试点工作而设计开发,平台的搭建采用B/S架构实现多级用户、跨平台登录,采用XML及JSON等数据传输格式实现国家级、省级、台站级用户信息交互,实现农业气象观测XML数据传输状态的监控、台站端设备状态的评估以及数据内容的实时查询。  相似文献   

微生物菌群培养组学在动物医学中的应用     

彭娜  彭先启  乐敏 《畜牧兽医学报》2020,51(12):2942-2953

实验室条件下可培养的微生物约占自然界中微生物总数的1%，这限制了人们对99%未知微生物的认识和利用，而研究表明，那些“不可培养的微生物”是可以被开发和利用的，未能被纯培养的微生物才是未知微生物的主体。微生物培养组学探索利用多种培养条件和长时间的培养，结合基质辅助激光解吸电离飞行时间质谱法（MALDI-TOF-MS）和16S核糖体RNA（rRNA）测序可以大规模鉴定各种微生物，同时利用全基因组测序和宏基因组测序手段对未知微生物进行深入分析。本文综述了国内外近年来微生物菌群培养组学在反刍动物胃肠道、禽类盲肠及家畜鼻腔微生物菌群研究中的最新进展，探讨将动物体内菌群培养组学方法应用于动物疾病防治领域的可行性。作为一个新兴的研究方法，尽管该培养组学还存在一些不够成熟的方面，但它的发展前景十分广阔，微生物菌群培养组学方法和其他研究方法的互补已经逐渐成为发展兽医微生物学新的突破口。  相似文献   

海南兰科植物新记录     

叶康 《热带作物学报》2019,40(11):2261-2263

本文报道了海南兰科植物3新记录种,分别是全唇叉柱兰[Cheirostylis takeoi (Hayata) Schltr]、兰屿芋兰（Nervilia lanyuensis S. S. Ying）和台湾隐柱兰（Cryptostylis taiwaniana Masam）。凭证标本存于上海辰山植物园标本馆（CSH）。  相似文献   

高丹草种子萌发和幼苗生长对模拟盐碱互作胁迫的响应     

田 祺张会慧  孙广玉 《安徽农业科学》2014,(6):1707-1710,1736

为限制盐碱地高丹草种子萌发和幼苗生长的主导影响因素,将2种中性盐(NaCl、Na2SO4)和2种碱性盐(NaHCO3、Na2CO3)按照不同比例混合,模拟出16种盐碱互作条件,研究盐碱互作胁迫对高丹草种子萌发和幼苗生长的影响。结果表明,高丹草种子萌发及幼苗生长参数与总盐浓度、pH以及CO2-3和HCO-3浓度的影响较大,而CO2-3和HCO-3浓度又是影响pH的主要因素,总盐浓度和pH可作为影响高丹草种子萌发及幼苗生长的主导因素。但是,反映种子萌发参数的发芽率(Gr)、发芽势(Gp)、发芽指数(Gi)等指标以及反映幼苗生长参数的芽长(GL)、根长(RL)和侧根数(LRN)等指标对盐浓度和pH胁迫的敏感性不同,在相同等盐浓度下,随着pH的增加,GL、RL和LRN降低幅度较Gr、Gp、Gi等参数的降低幅度更为明显,盐害系数之间也存在明显的差异,说明盐浓度对高丹草种子萌发的影响较大,而高pH胁迫则主要影响其幼苗生长。因此,盐碱地高丹草的种植过程中不仅要考虑土壤含盐量的因素,而且要考虑pH的影响。  相似文献   

中、美学校体育课程设置比较分析*     

袁〓勇  毛伟琴  张〓鹏 《上海交通大学学报(农业科学版)》2014,(5):5-9

运用比较分析等方法，对宾夕法尼亚州和上海市学校体育课程设置进行比较分析发现，美国学校体育课程设置内容广泛，重视个体全面发展、注重人文关怀、注重各级学校体育课程衔接；提出上海市学校体育课程设置要提高衔接性、体育课程设置应该重视人文关怀，关注残疾人体育、充分利用体制优势，促进学生养成良好体育锻炼习惯、加强学校、家庭和社区的联动，构建完整体育活动圈等建议。以期为学校体育课程改革提供些许有益的参考，从而进一步促进学生身心健康。  相似文献   

邓州市耕地有效态硫元素丰缺状况分析、产生原因及应变对策     

张有成 《农业科学与技术》2014,(8):1348-1350

该文通过对邓州市2006~2007连续两年所分析的4700个土样有效硫（S）化验结果整理分析发现，邓州市目前近30%耕地中有效态硫含量对禾谷类作物而言是缺乏的，有近60%的耕地中有效态硫含量对于种植十字花科、百合科、豆科等需硫较多的作物来说，属于潜在缺硫耕地；同时从施肥结构、种植结构变化详细分析了其产生的原因，并依据硫在植物体内移动状况、硫肥性状等因素提出相应对策。  相似文献   

基于XML的科研管理信息系统研究   总被引：1，自引：0，他引：1  

余少云 《江西农业学报》2011,23(2)

该文在分析农业科研单位科研管理现状的基础上,提出了一种基于XML技术的科研管理信息系统,并进一步介绍了系统采用的B/C/S结构模型,阐述了系统的功能模块和系统实现的部分关键技术。得出该系统能降低对客户端的要求,减少系统的通讯量,使得数据的呈现、交互更加容易,从而提高了科研管理工作的效率。  相似文献   

Vineyard soil bacterial diversity and composition revealed by 16S rRNA genes: Differentiation by geographic features     

《Soil biology & biochemistry》2015

Here, we examine soil-borne microbial biogeography as a function of the features that define an American Viticultural Area (AVA), a geographically delimited American wine grape-growing region, defined for its distinguishing features of climate, geology, soils, physical features (topography and water), and elevation. In doing so, we lay a foundation upon which to link the terroir of wine back to the soil-borne microbial communities. The objective of this study is to elucidate the hierarchy of drivers of soil bacterial community structure in wine grape vineyards in Napa Valley, California. We measured differences in the soil bacterial and archaeal community composition and diversity by sequencing the fourth variable region of the small subunit ribosomal RNA gene (16S V4 rDNA). Soil bacterial communities were structured with respect to soil properties and AVA, demonstrating the complexity of soil microbial biogeography at the landscape scale and within the single land-use type. Location and edaphic variables that distinguish AVAs were the strongest explanatory factors for soil microbial community structure. Notably, the relationship with TC and TN of the <53 μm and 53–250 μm soil fractions offers support for the role of bacterial community structure rather than individual taxa on fine soil organic matter content. We reason that AVA, climate, and topography each affect soil microbial communities through their suite of impacts on soil properties. The identification of distinctive soil microbial communities associated with a given AVA lends support to the idea that soil microbial communities form a key in linking wine terroir back to the biotic components of the soil environment, suggesting that the relationship between soil microbial communities and wine terroir should be examined further.  相似文献   

Establishment of macro-aggregates and organic matter turnover by microbial communities in long-term incubated artificial soils     

《Soil biology & biochemistry》2014

The study of interactions between minerals, organic matter (OM) and microorganisms is essential for the understanding of soil functions such as OM turnover. Here, we present an interdisciplinary approach using artificial soils to study the establishment of the microbial community and the formation of macro-aggregates as a function of the mineral composition by using artificial soils. The defined composition of a model system enables to directly relate the development of microbial communities and soil structure to the presence of specific constituents. Five different artificial soil compositions were produced with two types of clay minerals (illite, montmorillonite), metal oxides (ferrihydrite, boehmite) and charcoal incubated with sterile manure and a microbial community derived from a natural soil. We used the artificial soils to analyse the response of these model soil systems to additional sterile manure supply (after 562 days). The artificial soils were subjected to a prolonged incubation period of more than two years (842 days) in order to take temporally dynamic processes into account. In our model systems with varying mineralogy, we expected a changing microbial community composition and an effect on macro-aggregation after OM addition, as the input of fresh substrate will re-activate the artificial soils. The abundance and structure of 16S rRNA gene and internal transcribed spacer (ITS) fragments amplified from total community DNA were studied by quantitative real-time PCR (qPCR) and denaturing gradient gel electrophoresis (DGGE), respectively. The formation of macro-aggregates (>2 mm), the total organic carbon (OC) and nitrogen (N) contents, the OC and N contents in particle size fractions and the CO₂ respiration were determined. The second manure input resulted in higher CO₂ respiration rates, 16S rRNA gene and ITS copy numbers, indicating a stronger response of the microbial community in the matured soil-like system. The type of clay minerals was identified as the most important factor determining the composition of the bacterial communities established. The additional OM and longer incubation time led to a re-formation of macro-aggregates which was significantly higher when montmorillonite was present. Thus, the type of clay mineral was decisive for both microbial community composition as well as macro-aggregation, whereas the addition of other components had a minor effect. Even though different bacterial communities were established depending on the artificial soil composition, the amount and quality of the OM did not show significant differences supporting the concept of functional redundancy.  相似文献