大棚黄瓜光合作用日变化及环境因素对光合作用的影响

以长春密刺黄瓜为试材,对大棚黄瓜的光合作用规律进行了探讨。大棚黄瓜存在的明显的光合“午休”现象,中午叶温升高,大气湿度下降造成气孔导度下降是形成光合“休午”的外部原因。温度和光量子通道密度明显影响黄瓜的光合作用,其中光合适温为２８～３５℃光饱和点为１８００μｍｏｌ．ｍ＾－２．ｓ＾－１,补偿点为４５．７７６μｍｏｌ．ｍ＾－２．ｓ＾－１老叶的光饱和点补偿点均比健壮叶片低。适当提高白天棚温度,尽量增加加     

黄瓜对不同温度逆境的抗性研究

研究和比较了黄瓜幼苗对温度逆境的抗性。耐低温能力较强的自交系耐高温能力亦较强;而耐低温能力较差的自交系耐高温能力也较差,说明部分品种的黄瓜幼苗对不同温度逆境抗性之间存在一定的相关性。高温和低温对黄瓜种子的发芽能力影响不同,低温对发芽率的影响不大,仅延缓了发芽的速度;高温显著降低抗性较弱品系的发芽率。温度逆境胁迫使叶绿素含量明显降低,而且以叶绿素a下降为主。温度逆境胁迫后,Gs下降,但Ls显著降低,AQE和CE降低,Ci上升,说明叶片的光合机制遭到了明显破坏,非气孔因素是Pn降低的主要原因。结果表明,黄瓜幼苗对不同温度逆境在某些抗性方面存在一定的相关性,其机理尚待进一步探讨。     

Identification of novel immunogenic proteins of Vibrio alginolyticus by immunoproteomic methodologies

Vibrio alginolyticus is one of the most serious diseases in cultured marine and freshwater fish and shellfish. The absence of suitable vaccine or virulent marker can be the bottleneck to control V. alginolyticus infection. In this study, immunoproteomic approaches were undertaken to study the immunogenicity of the whole‐cell protein of V. alginolyticus HY9901. The whole‐cell proteins were analysed by two‐dimensional gel electrophoresis and subsequent immunoblotting using the rabbit anti‐V. alginolyticus HY9901 serum. A total of 55 immunogenic proteins were identified by immunoproteomic analysis. Of the 55 proteins, 51 are specific immunoreactive proteins and four are nonspecific immunoreactive proteins. Furthermore, outer membrane protein N (spot 2) was used as immunogens to immunize Epinephelus coioides for investigation of protective abilities and activities. The E. coioides immunized with OmpN has abilities to fight against infections caused by V. alginolyticus. The other novel immunogenic proteins may be developed as alternative antigens for further study of V. alginolyticus vaccine and diagnostics. These data show that immunoproteomics methods can be successfully applied in identifying immunogenic proteins of V. alginolyticus, which helps to search for the protective antigens in future.     

六种检疫性储粮豆象防治研究进展

近年来,在进口货物上截获到很多的豆象,防治困难.本文介绍了莱豆象、巴西豆象、灰豆象、鹰嘴豆象、四纹豆象、绿豆象等几种检疫性豆象防治的研究进展.     

贝类派琴虫和折光马尔太虫二重PCR方法的建立

根据基因库中派琴虫和折光马尔太虫的基因序列,分别设计了二对特异性引物,通过对二重PCR扩增条件的优化,研究建立了可同时检测鉴别这二种原虫的多重PCR。该技术对同一样品中的派琴虫和折光马尔太虫模板进行扩增,结果均同时得到2条大小与实验设计相符的596bp（派琴虫）和478bp（折光马尔太虫）的特异性扩增带,而对单孢子虫、嗜水气单胞菌、荧光假单胞菌、副溶血弧菌、溶藻弧菌、河弧菌和拟态弧菌等病原体的扩增,结果全为阴性。敏感性试验结果表明,该技术最低能检测到10Pg的派琴虫和折光马尔太虫DNA。用该二重PCR对广西沿海的119份牡蛎样品进行检测,结果派琴虫和折光马尔太虫的阳性率分别为9．24％和1．68％,提示了中国南方沿海的养殖贝类中存在派琴虫和折光马尔太虫的感染。     

Isolation of avian influenza virus (H9N2) from emu in China

This is the first reported isolation of avian influenza virus (AIV) from emu in China. An outbreak of AIV infection occurred at an emu farm that housed 40 four-month-old birds. Various degrees of haemorrhage were discovered in the tissues of affected emus. Cell degeneration and necrosis were observed microscopically. Electron microscopy revealed round or oval virions with a diameter of 80 nm to 120 nm, surrounded by an envelope with spikes. The virus was classified as low pathogenic AIV (LPAIV), according to OIE standards. It was named A/Emu/HeNen/14/2004(H9N2)(Emu/HN/2004). The HA gene (1683bp) was amplified by RT-PCR and it was compared with other animal H9N2 AIV sequences in GenBank, the US National Institutes of Health genetic sequence database. The results suggested that Emu/HN/2004 may have come from an avian influenza virus (H9N2) from Southern China.     

雏鸡在感染IBDV后红细胞免疫功能变化的研究

在经ＩＢＤ弱毒苗免疫和未免疫的３０～５９日龄ＡＡ鸡研究了感染ＩＢＤＶ后红细胞免疫功能的变化。结果表明：从以ＩＢＤＶ攻毒前１天到攻毒后头５天内,未免疫攻毒鸡（Ａ组）和免疫攻毒鸡（Ｂ组）ＲＢＣ－ＣＲ１花环率降低或显著降低,而未免疫未攻毒鸡（Ｃ组）没有类似变化,高于Ｂ组,明显高于Ａ组,以后Ａ和Ｂ组逐渐回升到攻毒前水平。Ａ和Ｂ组ＲＢＣ－ＩＣ花环率在ＩＢＤＶ攻毒后第５天明显降低,均显著低于Ｃ组水平,以后Ａ组仍处于较低水平上变动,Ｂ组即逐渐回升,三组比较,Ａ组仍低于Ｃ组,同时也低于Ｂ组。     

贝类派琴虫和折光马尔太虫二重PCR方法的建立

根据基因库中派琴虫和折光马尔太虫的基因序列,分别设计了二对特异性引物,通过对二重PCR扩增条件的优化,研究建立了可同时检测鉴别这二种原虫的多重PCR。该技术对同一样品中的派琴虫和折光马尔太虫模板进行扩增,结果均同时得到2条大小与实验设计相符的596bp(派琴虫)和478bp(折光马尔太虫)的特异性扩增带,而对单孢子虫、嗜水气单胞菌、荧光假单胞菌、副溶血弧菌、溶藻弧菌、河弧菌和拟态弧菌等病原体的扩增,结果全为阴性。敏感性试验结果表明,该技术最低能检测到10pg的派琴虫和折光马尔太虫DNA。用该二重PCR对广西沿海的119份牡蛎样品进行检测,结果派琴虫和折光马尔太虫的阳性率分别为9.24%和1.68%,提示了中国南方沿海的养殖贝类中存在派琴虫和折光马尔太虫的感染。     

牛轮状病毒三种核酸检测方法的比较

利用针对牛轮状病毒（BRV）的普通PCR、实时荧光定量PCR（Real-time PCR）和环介导等温扩增技术（LAMP）三种核酸检测方法对不同质粒浓度的样品和417份临床疑似样品进行检测,比较三种核酸检测方法的检出结果。三种核酸检测方法中LAMP最敏感敏感,能检测到1拷贝/μL,Real-time PCR能检测到100拷贝/μL,普通PCR只能检测到1×104拷贝/μL。但结合临床样品检测表明：常规PCR方法敏感度低会造成一部分漏检,LAMP灵敏度高又会造成错检。综合比较三种方法后,推荐用LAMP结合real-time PCR,不仅节约成本,且结果更为准确可靠,可提高牛轮状病毒的检出率。