猪繁殖与呼吸综合征病毒新疆株ORF3基因的克隆与测序

根据GenBank中已发表的猪繁殖与呼吸综合征病毒ORF3基因序列,设计合成了1对特异性引物,扩增出病毒ORF3结构基因。将该基因克隆到pMD18-T,构建了重组质粒pMD18-ORF3,并对筛选出的阳性质粒进行测序。应用序列分析软件对测序结果分析可知,克隆得到的ORF3基因组全长812 bp。通过DNAman对所测ORF3基因核苷酸序列与GenBank中登录的国内外PRRSV毒株核苷酸序列进行同源性比较。序列分析结果显示,XJPRRSV1/03与参考毒株VR2332、LV、CH-1a的核苷酸同源性分别为95.8%,89.8%,92.7%,氨基酸同源性分别为96.6%,88.5%,93.2%。XJPRRSV1/03与VR2332同源性最高。     

2BMMD-4型夏棉精量免耕播种机的设计与试验

鉴于黄淮海麦棉轮作区土层深厚和根茬量大、韧性强的特点,以及免耕播种机作业要求,设计了2BMMD-4型棉花精量免耕播种机,能一次实现破茬、开沟、防堵、施肥、播种、覆土及镇压等功能。该机具具有独特的苗带清理及作业防堵、播种深度调节以及作业仿形功能。同时,利用SolidWorks以及ANSYS软件对2BMMD-4型免耕播种机的苗带浅旋装置进行了模态分析。结果表明,该机刀轴在设计转速下对应的频率远小于各阶固有频率,不容易发生共振。田间试验表明,该播种机作业性能达到了设计要求。     

《林业科学》1997～2001年论文及作者统计分析

该文用文献计量学的原理与方法,以《林业科学》1997-2001年5年间发表的论文及作者作为统计对象,分别就发文量、论文选题、作者的合作废和合著率、作者系统及地区分布、多产作者与多产单位及作者增复量等方面进行了统计分析,从一个侧面反映了我国林业科学研究的一些规律。     

杉木大径材优树选择与主要经济性状变异分析

以胸径为选择指标,对杉木初级种子园23年生子代林大径材优树（胸径≥26cm）进行选择,共有38个优良单株入选,结果表明：优树胸径现实增益值均超过56％;树高、胸径、单株材积、树皮比率、木材基本密度和木材吸水性等主要经济性状在优树间变异较为广泛,变异系数在10％以上;树高、胸径、单株材积、木材吸水性间呈正相关关系,且达显著或极显著水平,而树皮比率与胸径及单株材积间、木材基本密度与各生长性状及木材吸水性间则为负相关关系,达显著或极显著水平。对大径材优树有效材积（去皮后单株材积）一木材基本密度类型作初步划分发现,共17株优树有效材积值大于优树群体均值,其中优树S14、S18、S22、S25木材基本密度大于优树群体均值。     

Normative Analysis and Strategy Research on Harmonized Development of Modern Industrialization,Urbanization, Agricultural Modernization and IT Application

我国的现代化建设必须要坚持走中国特色的新型工业化、信息化、城镇化、农业现代化（以下简称“四化”）同步发展的道路。文章阐述了“四化”同步发展的科学内涵,并对“四化”之间的相关系系做了论证,在对我国“四化”存在问题分析的基础上。提出了加快信息化进程,实现“四化”同步发展的对策措旋。     

巢湖烔炀河水质空间分布特征及其改善策略

研究巢湖入湖河流炯炀河营养物质(N、P)和化学需氧量(CODcr)的空间分布特征,采用基于主成分分析(PCA)构造的多指标综合评价体系表征了河流水质空间变化趋势.炯炀河各段水质受到流域人类活动和河流自净功能的双重影响.上游炯河段污染最重,其F因子均值为1.03(范围0.05～1.64),主要是由炯炀镇生活污水排放、沿河固体废弃物堆积、农业面源污染等人类活动所致.炀河段水质相对较好,其F因子均值为-0.03(范围-0.08～0.04).炯河、炀河汇合后的炯炀河段水质自上游至下游总体上呈现先变差、后变好的趋势,其F因子均值为-0.30(范围-0.66～0.28),沿途农业面源污染对河水水质产生了显著影响.采用PCA分析对河流各项水质因子载荷大小比较后得出N、P是炯炀河水质的主控因子,第一主成分氮磷营养因子解释了河流水质空间变异的约60％.提出了炯炀河水质改善策略,为炯炀河生态型小流域规划与建设提供可行方案,为巢湖水环境治理决策提供科学依据.     

水稻杂种直链淀粉含量的遗传分析

本试验在单粒测定直链淀粉含量的条件下,对水稻杂种F_1,F_2、F_3种子进行直链淀粉含量遗传模式的探讨。结果表明:基因剂量效应仅存在部分组合。在高、中直链淀粉含量籼稻/低直链淀粉含量籼稻正反交组合中,高、中直链淀粉含量对低直链淀粉含量表现为完全显性,F_2为3:1分离,受一对基因控制。部分超亲分离表明可能还受修饰基因的影响。     

High HEV presence in four different wild boar populations in East and West Germany

Swine Hepatitis E virus (HEV) can be transmitted from pigs to humans causing hepatitis. A high prevalence of HEV in wild boar populations is reported for several European countries, but actual data for Germany are missing. During the hunting season from October to December 2007 liver, bile and blood samples were collected from wild boars in four different German regions. The samples were tested for HEV RNA by quantitative PCR (qPCR) and anti-HEV IgG antibodies by two different ELISAs and a Line immunoassay. A seroprevalence of 29.9% using ELISA and 26.2% in the Line immunoassay was determined. The seroprevalence rate varied greatly within the analyzed regions. However, qPCR analysis revealed a higher prevalence of 68.2% positive animals with regional differences. Surprisingly, also adult wild sows and wild boars were highly HEV positive by qPCR. Compared to liver and serum samples, bile samples showed a higher rate of positive qPCR results. Sequencing and phylogenetic analysis of a 969 nt fragment within ORF 2 revealed that all isolates clustered within genotype 3 but differed in the subtype depending on the hunting spot. Isolates clustered within genotypes 3i, 3h, 3f and 3e. Within one population HEV isolates were closely related, but social groups of animals in close proximity might be infected with different subtypes. Two full-length genomes of subtypes 3i and 3e from two different geographic regions were generated. The wild boar is discussed as one of the main sources of human autochthonous infections in Germany.     

Herd characteristics influence farmers’ preferences for trait improvements in Danish Red and Danish Jersey cows

The aim of this study was to characterize preferences of farmers for breeding goal traits with Danish Red (DR) or Danish Jersey (DJ) cows. A breed-specific survey was established to characterize farmers’ preferences for improvements in 10 traits, by means of pairwise rankings using the online software 1000Minds. These pairwise rankings were based on equal economic worth of trait improvements. The DR survey was filled in by 87 farmers and the DJ survey by 76 farmers. Both DR and DJ farmers gave the highest preference to improvements in mastitis, and the lowest to calving difficulty. By means of a cluster analysis, three distinct clusters of farmers were identified per breed. Comparisons of herd characteristics between clusters suggest that farmers choose to improve traits that are problematic in their herds. This study shows that heterogeneity exists in farmers’ preferences for trait improvements and that herd characteristics influence these preferences in DR and DJ.     

油菜育种亲本主要性状相关性及主成分分析

为了有效评价油菜不同亲本材料,筛选获得可用于油菜育种的优良亲本,并对油菜性状基本遗传规律进行探讨。以国内外18个油菜育种亲本为材料,对油菜11个主要农艺性状进行了相关性和主成分分析。油菜亲本间主要农艺性状的表型差异较大,不同性状的变异系数介于0.09~0.31之间,其中单株产量的变化最大,株高的变化最小;油菜主要农艺性状的相关性差异明显,角果数相关性状与单株产量的相关性表现较好,而不同部位分枝间距与其他性状的相关性均较差;在获得的4个主成分中,除第1主成分主要由角果数和单株产量构成外,其余3个主成分均以不同部位分枝间距为主。油菜育种实践中应同时注重对主要目标性状及其相关性状的有效改良,本研究将为油菜种质有效利用和油菜性状改良提供一定的科学依据。