河南省农用大中型拖拉机需求量预测研究

河南省农用大中型拖拉机受国家政策、经济效益、市场需求等多种因素的影响,其需求量是一个复杂的非线性系统。为此,首先在灰色GM（1,1）模型基础上,利用BP神经网络修正残差,建立灰色 BP 神经网络组合预测模型,既克服了数据的非线性关系以及随机波动大对预测精度的影响,也增强了预测的自适应性。为此,对2002-2011年河南省农用大中型拖拉机的拥有量进行了检验预测,结果表明模型具有较高的拟合度。最后,应用该模型预测了河南省2012-2015农用大中型拖拉机的拥有量,并依此测算出河南省农用大中型拖拉机未来4年的需求量,可为河南省农机部门制定农机动力发展规划提供参考。     

Identification and fine mapping of a candidate gene for oil yellow leaf 2 conferring yellow leaf phenotype in maize

Leaf colour is an important agronomic trait for studying molecular mechanisms in chlorophyll biosynthesis and chloroplast development. Here, a novel mutant oil yellow leaf 2 (Oy2) with a typical yellow leaf phenotype at the seedling stage was identified from the mutant population derived from the maize inbred line RP125. Compared with wild type, Oy2 mutant displays decreased chlorophyll content, reduced photosynthetic capacity and impaired chloroplast structure, which is likely controlled by a single recessive gene. The Oy2 locus was then delimited into a 117 kb region on chromosome 5 harbouring four genes, amongst which the gene Zm00001d013013, encoding a magnesium chelatase subunit D, was identified as the only candidate gene associated with Oy2 mutant phenotype. Moreover, the expression levels of candidate gene Oy2 and genes associated with chlorophyll biosynthesis and photosynthesis were tested by RNA‐seq and qRT‐PCR, implying that the causal gene Oy2 playing a critical role in chlorophyll synthesis. Taken together, we propose that the causal gene Oy2 highly associated with the yellow leaf phenotype may be helpful in elucidating photosynthetic pigments biosynthesis and chloroplast development in maize.     

湖北省日本落叶松人工林立地分类及质量评价

研究旨在建立湖北省日本落叶松人工林立地分类及质量评价系统,为湖北省日本落叶松人工林营林造林提供理论指导。以湖北省日本落叶松人工林为研究对象,通过调查测定80块具有代表性的日本落叶松标准地,利用主成分分析法与数量化理论Ⅰ对研究区日本落叶松人工林进行立地分类与立地质量评价。主成分分析结果表明,海拔、土层厚度、坡位、坡度、坡向5个立地因子为影响日本落叶松生长的主导立地因子,累积贡献率所包含的信息占总体信息的84.803%。数量化分析的结果表明,5个主导立地因子与基准变量拟合模型的复相关系数(R)为0.7362,中坡度、厚土层、中海拔、阳坡、中坡位立地条件更有利于日本落叶松的生长。结合因子贡献率对研究区日本落叶松人工林进行立地类型划分,共划分为16个立地类型,并对16个立地类型按照优、良、中、差4个立地等级进行评价,结果表明,研究区有90%的样地立地质量处于中上水平,较适宜日本落叶松的发展。     

花生网斑病化学防治药剂及复配增效配方的筛选

为了筛选防治花生网斑病菌的有效药剂,采用菌丝生长速率法测定12种杀菌剂原药对花生网斑病菌的室内毒力活性,筛选出防效较好的杀菌剂;选取不同类型的杀菌剂进行复配,并对花生网斑病菌进行室内毒力测定试验。结果表明:95%咯菌腈、98.6%嘧菌酯、97%咪鲜胺、95%苯醚甲环唑、95%己唑醇、95%甲基硫菌灵、97%戊唑醇对花生网斑病菌具有较强的抑制作用。87%代森联与97%咪鲜胺按1:9复配时,具有增效作用,EC₅₀值为0.673 μg/mL。室内杀菌剂毒力测定结果显示试验选取的单剂和复配药剂均对花生网斑病菌的菌丝生长具有抑制效果,该结果为花生网斑病的研究提供了理论依据,为下一步田间防效试验奠定基础。     

非洲猪瘟病毒LNA引物PCR检测方法的建立及优化

为了建立一种便捷、快速且精准的非洲猪瘟病毒的检测方法,本研究根据GenBank中公布的ASFV p72基因序列,设计了一对特异性引物,并对引物中的适当碱基进行锁核酸修饰,通过优化退火温度、引物浓度,建立了非洲猪瘟病毒的锁核酸修饰引物PCR检测方法。结果表明,该方法具有良好的敏感性和特异性,检测灵敏度可以达到3×10¹ copies/uL,比常规引物PCR方法的灵敏度提高了100倍,比real-time PCR方法的灵敏度提高了10倍,对猪瘟病毒、猪圆环病毒2型、猪伪狂犬病毒等病原基因组均无扩增,特异性良好。72份临床样品的检测结果与OIE推荐的qPCR方法检测结果一致,符合率为100%。本研究成功建立了非洲猪瘟病毒的LNA引物PCR检测方法,方法的特异性强、敏感性高,操作简单,为非洲猪瘟病毒的检测提供了一种新的、更加敏感的检测技术。     

生态文明视角下乡村休闲渔业发展现状与路径选择——基于对漳州市澳角村的实证研究

基于生态文明视角,采用实地考察、问卷调查、入户访谈等方式,就漳州市澳角村乡村休闲渔业发展现状及发展困境进行实证分析。简要介绍当地休闲渔业发展有利的自然、社会基础以及为推动渔业发展所采取的有效措施,总结当地创新发展的思路和发展困难所在。从拓宽发展渠道,提高村财收入、强化招商引资,推动项目建设、提高宣传意识,吸引游客观光等方面,提出乡村休闲渔业发展的思路,以期为当地适应新环境、新需求,实现"富美乡村"目标提供可行性对策与建议。     

Effects of inoculants on the fermentation characteristics and in vitro digestibility of reed canary grass (Phalaris arundinacea L.) silage on the Qinghai‐Tibetan Plateau

To effectively use local available grass resources to cover the winter feed shortage on the Qinghai‐Tibetan Plateau, direct‐cut and wilted reed canary grass (RCG) silages were prepared by using a rolled‐bale system, and their ensiling characteristics and in vitro digestibility were studied. Silages were treated without (control) or with inoculants including LP (Lactobacillus plantarum), LPLB (L. plantarum, L. buchneri), and LPLBc (L. plantarum, L. buchneri, and cellulase), and were stored at ambient temperature (5.7–14.6°C) for 90 days. Compared with control, the inoculated silages increased (p < .05) lactic acid and acetic acid contents, and reduced (p < .05) final pH value and ammonia‐N ratio of total N. The highest WSC content (41.2 g/kg DM) occurred for LPLB‐inoculated silage, whereas LPLBc‐treated silage displayed the lowest contents of NDF (522.9 g/kg DM) and ADF (275.5 g/kg DM). In addition, LPLBc‐inoculated silage had the highest in vitro gas production (51.0 ml/g DM), in vitro DM digestibility (619.3 g/kg DM), and metabolic energy (9.6 kJ/kg DM). These results confirmed that treatments with inoculants at ensiling could improve silage fermentation and in vitro digestibility of RCG, and this could be a potential winter feed for animals on the Qinghai‐Tibetan Plateau.     

苏云金杆菌H-14对致倦库蚊子_1代的影响

用14×10~3/ml的BtH-14菌液处理亲代第4龄致倦库蚊幼,观察其子_1代生命表特征。经与对照组比较,处理组蚊虫的净生殖率降低16.49％,雌蚊年均产卵量减少33％,世代周期延长约9天。     

贝莱斯芽孢杆菌BP-1对花生网斑病菌的抑菌机制初探

以不同浓度贝莱斯芽孢杆菌BP-1的发酵滤液处理花生网斑病菌孢子,采用显微观察法、电导率测定法和紫外吸收法测定发酵滤液对病菌细胞膜渗透性、麦角甾醇含量、脂质过氧化程度和可溶性蛋白质含量的影响,研究BP-1发酵滤液对花生网斑病菌孢子的抑制作用.结果 表明:BP-1发酵滤液可致花生网斑病菌孢子畸形、破裂;并可导致菌丝体内电解质泄漏,细胞膜上麦角甾醇的合成受阻,脂质过氧化产物(丙二醛)含量明显升高,同时显著抑制菌丝体内蛋白质含量.     

5％吡丙醚漂浮粒剂配方筛选及对蚊幼防治效果

针对目前吡丙醚加工剂型存在有机溶剂污染严重及漂浮、扩散性能差等问题,采用挤压造粒工艺,通过单一变量法筛选载体、润湿剂、分散剂、粘结剂、崩解剂和填料等配方组分,制备5％吡丙醚漂浮粒剂,并测定漂浮粒剂对蚊幼的防治效果.结果 表明:5％吡丙醚漂浮粒剂的优化配方为5％吡丙醚、35％空心玻璃微珠、8％分散剂Dis-201、4％润湿剂Wet-202、5％ PVP、8％尿素和35％硅藻土.所获得的5％吡丙醚漂浮粒剂的悬浮率高,扩散性能较好,对淡色库蚊3龄蚊幼具有较高的致死活性,其LC50为0.1066mg· L-1.这一研究对农药省力化剂型的制备及应用具有一定的借鉴作用.