微波辐射和浸种对华山松种子生活力和发芽的影响

为了解微波辐射和清水2因素不同水平组合对华山松种子吸水、生活力和种仁发芽率的影响,以及微波辐射结合清水和GA₃溶液浸种3因素对华山松种子发芽率的影响,采用L₉(3⁴)正交设计开展试验实施。结果表明：微波辐射和清水浸种处理组合的种子生活力、种子、种仁和种壳吸水率分别为75.3%～88.0%（CK的为94.7%）、6.63%～10.44%、15.00%～23.80%和0.98%～4.87%,处理组合间种子和种仁吸水率均具有极显著的差异（P < 0.01）;影响生活力的主导因子是微波辐射和清水浸种时间的交互作用,影响种子和种仁吸水率的则是清水浸种时间;测定（TTC法）的和未测定生活力的种仁发芽率分别为4.0%～22.8%和52.7%～90.0%,CK的为4.7%和60.0%,微波辐射是影响种仁发芽率的主导因子。微波辐射结合清水和GA₃溶液浸种的组合,种子场圃发芽率为56.0%～71.6%（CK的为56.0%）,清水和GA₃浸种的交互作用是影响种子场圃发芽率的主导因子。微波辐射和清水浸种的组合降低种子生活力。清水浸种8 h时,种子吸水基本达到饱和;微波辐射15 s,清水浸种12 h后0.05 g/L GA₃溶液浸种,提高华山松种子场圃发芽率,可应用于生产实践。     

Development and application of G1-ELISA for detection of antibodies against bovine ephemeral fever virus

The gene encoding antigenic site G₁ of bovine ephemeral fever virus (BEFV) was highly expressed in the host cell Escherichia coli. An indirect G₁-ELISA with the recombinant protein as the coating antigen was established to detect antibodies against BEFV. The result revealed that the optimal concentration of the coated antigen was 0.5 μg/well and the dilution of serum was 1:20. It was optimal that sera with P/N value  2.2 were considered positive, P/N value  2.0 negative, and between 2.0 and 2.2 ambiguous. The G₁-ELISA method gave a sensitivity of 97.6% and a specificity of 98.6% by testing 590 field serum samples. These results suggest that the G₁-ELISA may be a good alternative tool for seroepidemiological surveys.     

基于超平面构建的高光谱异常目标检测方法

高光谱遥感影像具有光谱分辨率高、图谱合一的特点,影像中的地物组成也多种多样,针对图像数据中目标出现概率较小、检测概率较低等问题,本文提出了基于超平面构建的高光谱数据目标异常检测方法。它通过对高光谱数据的结构分析,构建出高维空间中的背景超平面算子,以待测像元在其正交子空间的投影值来表征异常程度的大小。通过OMIS和AVIRIS实测数据验证,并与RX算法相比较,基于超平面构建的高光谱异常检测算法能够在多种背景环境下检测出纯度高、光谱差异大的异常像元,并具有较高的检测率和较低的虚警率,因此具备了有效性和较好的实用性。     

利用家蚕蛹人工繁殖自蛾周氏啮小蜂的研究

初步研究了利用家蚕蛹大量繁殖白蛾周氏啮小蜂的可行性。观察了白蛾周氏啮小蜂在家蚕蛹上的发育历期,子代蜂的寿命及飞行能力,认为繁蜂的最佳蜂蛹比为15～20∶1;4次接蜂结果显示,周氏啮小蜂可以利用家蚕蛹连续繁殖,单蛹出蜂量及单雌产卵量均较高;利用家蚕蛹繁殖的白蛾周氏啮小蜂对国槐尺蛾蛹寄生率为76.7%,表明利用家蚕蛹繁殖的子代蜂对其他寄主具有较强的寄生能力。     

4种实蝇线粒体DNA全序列测定

橘小实蝇(Bactrocera dorsalis)、木瓜实蝇(Bactrocera papayae)、杨桃实蝇(Bactrocera carambolae)和菲律宾实蝇(Bactrocera philippinensis)的成虫和幼虫的形态特征十分相近,难以区分.本文对4种实蝇的线粒体DNA全序列进行测定,序列在GenBank上登录(登录号分别为:DQ917577,DQ917578,EF014414,DQ995281),并对4个种的线粒体DNA全序列进行序列分析,为建立基于线粒体DNA序列分析的快速鉴定方法提供基础.     

三唑酰草胺在不同类型土壤中的降解特性

为科学评价除草剂三唑酰草胺在土壤环境中的生态风险,采用室内模拟方法,研究了三唑酰草胺在吉林黑土、江西红土和安徽水稻土中的降解特性。结果表明:三唑酰草胺在土壤中的降解符合一级动力学方程。好氧条件下三唑酰草胺在3种土壤中的降解半衰期分别为86.5、106和91.4 d;厌氧条件下半衰期分别为106、130和127 d;水稻田厌氧条件下半衰期分别为162、219和188 d。研究表明,三唑酰草胺在水稻田厌氧条件下的降解速率明显慢于其他2种试验条件下。     

苍耳不同分离物对害虫的拒食和忌避活性

为跟踪分离苍耳的活性成分,对苍耳叶和果实的甲醇提取物进行了液-液萃取分离,测试各萃取分离物对小菜蛾(Plutella xylostella)、菜青虫(Pieris rapae)和桃蚜(Myzus persicae)的拒食、忌避(或产卵忌避)活性以及对其化蛹和羽化的影响。结果显示,苍耳的乙酸乙酯分离物较之于甲醇水分离物具有更高的活性。在0.05 g/mL处理浓度下,苍耳叶乙酸乙酯分离物对菜青虫和小菜蛾幼虫选择性拒食率高达100%和44.13%,对菜青虫非选择性拒食率为94%,对小菜蛾的选择性产卵忌避率都在50%以上,对桃蚜的选择性忌避率高于70%;同时,苍耳果实乙酸乙酯分离物处理叶片后,菜青虫幼虫无一化蛹,小菜蛾高龄幼虫发育为成虫的比率仅为对照的13.80%。以上结果提示,苍耳的有效活性成分主要存在于乙酸乙酯分离相中,对菜青虫的作用效果好于小菜蛾。     

川西北牦牛新孢子虫感染血清流行病学调查

目的 了解川西北牦牛新孢子虫的感染情况.方法 采用间接ELISA方法对川西北阿坝州8个县1 070份待屠宰牦牛血清中新孢子虫抗体进行检测.结果 被检1 070份血清样品中65份血清新孢子虫抗体呈阳性,样品来源的8个县都检测到了新孢子虫抗体,被检牦牛的血清抗体平均阳性率为6.1％,其中理县(12.2％)的抗体阳性率显著高于平均水平(p＜0.01),马尔康的最低为2.7％.结论 川西北阿坝州各县广泛存在牦牛新孢子虫感染.     

Risk-based surveillance for avian influenza control along poultry market chains in South China: The value of social network analysis

Over the past two decades, the poultry sector in China went through a phase of tremendous growth as well as rapid intensification and concentration. Highly pathogenic avian influenza virus (HPAIV) subtype H5N1 was first detected in 1996 in Guangdong province, South China and started spreading throughout Asia in early 2004. Since then, control of the disease in China has relied heavily on wide-scale preventive vaccination combined with movement control, quarantine and stamping out. This strategy has been successful in drastically reducing the number of outbreaks during the past 5years. However, HPAIV H5N1 is still circulating and is regularly isolated in traditional live bird markets (LBMs) where viral infection can persist, which represent a public health hazard for people visiting them. The use of social network analysis in combination with epidemiological surveillance in South China has identified areas where the success of current strategies for HPAI control in the poultry production sector may benefit from better knowledge of poultry trading patterns and the LBM network configuration as well as their capacity for maintaining HPAIV H5N1 infection. We produced a set of LBM network maps and estimated the associated risk of HPAIV H5N1 within LBMs and along poultry market chains, providing new insights into how live poultry trade and infection are intertwined. More specifically, our study provides evidence that several biosecurity factors such as daily cage cleaning, daily cage disinfection or manure processing contribute to a reduction in HPAIV H5N1 presence in LBMs. Of significant importance is that the results of our study also show the association between social network indicators and the presence of HPAIV H5N1 in specific network configurations such as the one represented by the counties of origin of the birds traded in LBMs. This new information could be used to develop more targeted and effective control interventions.     

湘研十五号辣椒的选育

湘研十五号辣椒是以６４２４为母本,８２１５为父本配制一代杂种,植株生长势强,株型紧凑,丰产、稳产,抗病性强,一般６６７ｍ＾２产量３０００ｋｇ左右,比湘研五号增产１５．３６％。