Energy Metabolism Pattern in Cotton Aphid,Aphis gossypii Glover （Hem.： Aphididae） Exposure to Neonicotinoids

This study was mainly made on the role of energy revisers in cotton aphid, Aphis gossypii Glover （Hemiptera： Aphididae） countered with imidacloprid and thiametoxam. We measured used energy, available energy and the content of total energy in three strains of cotton aphid which were from very resistant to neonicotinoid, sup to semi-sensitive and sensitive speccies, respectively. It was observed changes in energy resources rate in all of the aphid strains at which each substrate was metabolized under stress. Our findings indicated among energy sources, total lipid in susceptible strain was increased in counter of spraying and it was decreased in resistance and semi sensitive strains. Whereas, total protein was decreased in all of the strains encountering with neonicotiniod stress. Total glycogen was increased significantly in different aphid strains and sugar was decreased in countered of spraying.     

Comparison of Acetylcholinesterase Characteristics Between Resistant and Susceptible Strains of Helicoverpa armigera （Hubner）

The sensitivity of a susceptible and two resistant strains of cotton bollworm, Helicoverpa armigera, to phoxim, malathion and methomyl was determined by a topical application of bioassay method. YG strain, collected from field of Yanggu, Shandong Province of China, possessed 7-, 13- and 20-fold of resistance to the above three antiacetylcholinesterases based on the comparison of LD50 values with a laboratory susceptible strain. There were not significant difference of the specific activity and the Vmax value among the three strains. But the affinity of AChE tO acetylthiocholine （ATCh）, in YG strain was the lowest among the three strains tested. A cDNA encoding partial AChE gene was cloned from the three strains by RT-PCR and there was one nucleotide acid difference between YG strain and other two strains which resulted in no amino acid mutation. This partial AChE gene was used as a probe to perform Southern blot. The results indicated that there was no gene amplification in resistant cotton bollworm. Altered AChE with a decreased sensitivity to inhibitors appeared to be one of important resistance mechanisms in cotton bollworm against OP and carbamate compounds.     

Pathotype Structure of Magnaporthe grisea in the Fields of Chongyang and Yuan’an in Hubei Province,China

[Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan’an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan’an in Hubei Province where rice blast occurs frequently,60 isolates which were pathotyped against two sets of host differentials:Chinese host differentials and CO39 NILs,were obtained.Then,20 pathotypes with the six indica host differentials(CO39 NILs) were observed,while 13 pathotypes in four race groups were observed out of the same single spore isolates with Chinese host differentials which consists of three indica cultivars and four japonica cultivars.The diversity of the pathotypes of M.grisea populations tested by CO39 NILs was 2.54 and the pathotype 137.1 occurred at predominantly high frequency(21.67%).The diversity of physiological races of M.grisea populations tested by Chinese host differentials was 1.22 and the race group ZA occurred at predominantly high frequency(73.33%).The diversity of physiological races of M.grisea in Chongyang and Yuan’an were also calculated.Overall,the diversity of pathotypes of M.grisea in Yuan’an was higher than that in Chongyang with the two sets of the host differentials.[Conclusion] This study provided current information on the pathotype spectrum of M.grisea populations in the rice fields of Hubei Province to allow the formulation of viable strategies for blast resistance breeding programs in Hubei Province.     

GyrA and ParC Gene Mutation of Clinically Isolated Fluoroquinolones-resistant Strain of Salmonella

Nine strains resistant to five fluoroquinolones (Ciprofloxacin, Ofloxacin, Enrofloxacin, Danofloxacin, Sarafloxacin) were isolated from clinical samples and extracted the chromosomal DNA of these strains. Designed primers to amplify the Quinolone-resistance-determining region (QRDR) of gyrA and parC, then the PCR products were sequenced and analyzed. In comparision with NCTC5776, a single mutation was found at base 371 in gyrA of strain 38 which changed from C to T, and a single mutation was found at base 350 in gyrA of strain 60 which changed from A to C. No mutation was found in gyrA of the rest. The mutation of strain 38 led to an amino acid substitution of Arg99Cys and the mutation of 60 led to an amino acid substitution of Met 92 Leu. No mutation was found in parC QRDR of all the isolates. These results indicats that the DNA gyrase will be the primary target to salmonella of fluoroquinolone.     

Analysis of Two-Dimensional Gel Electrophoresis Images of Protein from Posterior Silk Gland of Silkworm （Bombyx mort） on Day 1 and Day 4 in the 5th Instar Stage

The posterior silk gland （PSG） of silkworm is an important organ where fibroin is synthesized and secreted exclusively. Because fibroin constitutes 75-80% of the silk filament, the mechanism governing fibroin secretion, quality and yield of cocoon can be elucidated by the study on the PSG. Using two-dimensional gel electrophoresis （2-DE） and image analysis system, the changes in the protein composition in the PSG cell were investigated on the day 1 （D1） and day 4 （D4） in the 5th instar stage from five different strains of silkworm （Bombyx mori）. While differences at protein level between days and strains were far less than those observed at the gene level using EST analysis. The change trends in protein composition from D1 to D4 were diverse among the different strains. The results suggest that the secretion of fibroin is regulated by multiple proteins. The site of regulation and the proteins responsible for the regulation vary with the strain, which leads to differences between strains in the capacity of fibroin secretion in the PSG cell.     

枯草芽孢杆菌B47高产拮抗物质菌株的紫外诱变选育(英文)

[Objective] The aim of this study was to breed new strains which have higher inhibitory effects on the pathogens of watermelon fusarium wilt.[Method] The endophytic Bacillus subtilis B47 strain was obtained from tomato stems by UV mutagenesis for two consecutive times,then genetic stability as well as physiological and biochemical properties of mutant strains were studied.[Result] The antibacterial activity of all the three mutant strains F303,F304 and F305 was higher than that of B74 strain.After subculture of 10 successive generations,the antibacterial activity of all the three mutant strains for the pathogens of watermelon fusarium wilt decreased,but the antibacterial activity of F305 strain decreased the least,indicating its best genetic stability among the tested strains.The antibacterial circle diameter of F305 strain was 5 mm larger than that of wild strain B47 under the same condition.The mutant strain F305 was in logarithmic growth phase within 36 h and in stationary phase within 36-96 h,while its optimum growth temperature was 35 ℃.F305 strain could grow in sodium salt with the concentration of 1%-10%,but it grew best at the concentration of 1%.Physiological and biochemical responses of F305 strain were in accordance with those of wild strain B47.[Conclusion] This study lays the foundation for the factorial production of antagonistic substance by B47 strain and new methods of preventing from the pathogens watermelon fusarium wilt.     

枯草芽孢杆菌B47高产拮抗物质菌株的紫外诱变选育(英文)

[Objective] The aim of this study was to breed new strains which have higher inhibitory effects on the pathogens of watermelon fusarium wilt.[Method] The endophytic Bacillus subtilis B47 strain was obtained from tomato stems by UV mutagenesis for two consecutive times,then genetic stability as well as physiological and biochemical properties of mutant strains were studied.[Result] The antibacterial activity of all the three mutant strains F303,F304 and F305 was higher than that of B74 strain.After subculture of 10 successive generations,the antibacterial activity of all the three mutant strains for the pathogens of watermelon fusarium wilt decreased,but the antibacterial activity of F305 strain decreased the least,indicating its best genetic stability among the tested strains.The antibacterial circle diameter of F305 strain was 5 mm larger than that of wild strain B47 under the same condition.The mutant strain F305 was in logarithmic growth phase within 36 h and in stationary phase within 36-96 h,while its optimum growth temperature was 35 ℃.F305 strain could grow in sodium salt with the concentration of 1%-10%,but it grew best at the concentration of 1%.Physiological and biochemical responses of F305 strain were in accordance with those of wild strain B47.[Conclusion] This study lays the foundation for the factorial production of antagonistic substance by B47 strain and new methods of preventing from the pathogens watermelon fusarium wilt.     

Screening for the Strain Highly Producing Antagonistic Substance from Bacillus subtilis B47 by UV Mutagenesis

[Objective] The aim of this study was to breed new strains which have higher inhibitory effects on the pathogens of watermelon fusarium wilt.[Method] The endophytic Bacillus subtilis B47 strain was obtained from tomato stems by UV mutagenesis for two consecutive times,then genetic stability as well as physiological and biochemical properties of mutant strains were studied.[Result] The antibacterial activity of all the three mutant strains F303,F304 and F305 was higher than that of B74 strain.After subculture of 10 successive generations,the antibacterial activity of all the three mutant strains for the pathogens of watermelon fusarium wilt decreased,but the antibacterial activity of F305 strain decreased the least,indicating its best genetic stability among the tested strains.The antibacterial circle diameter of F305 strain was 5 mm larger than that of wild strain B47 under the same condition.The mutant strain F305 was in logarithmic growth phase within 36 h and in stationary phase within 36-96 h,while its optimum growth temperature was 35 ℃.F305 strain could grow in sodium salt with the concentration of 1%-10%,but it grew best at the concentration of 1%.Physiological and biochemical responses of F305 strain were in accordance with those of wild strain B47.[Conclusion] This study lays the foundation for the factorial production of antagonistic substance by B47 strain and new methods of preventing from the pathogens watermelon fusarium wilt.     

应用单抗EL试剂盒检测免疫鸡群新城疫强毒感染

A ELISA kit based on monoclonal antibodies was used to detect the infections of virulent Newcastle disease virus (NDV) in the experimentally immunized SPF chicken flocks. When cloacal samples from chickens infected with different pathotypes of NDV were assayed, only infections with virulent strains could be detected during the days 3～16 post-challenge, while infections with commonly used mesogenic and lentogenic vaccine strains, it couldn′t be detected. The results in this presentation indicated that the ELISA kit could be used for detecting and monitoring virulent NDV infection in chicken flocks.     

A Study on the Activity of Carboxylesterase and the Differential Expression of Its Gene in the Midguts of Bombyx mori Resistant to BmDNV-Z

This study was to discuss the relationship among the change in the activity of Bombyx mori carboxylesterase （BmCarE） in the midguts, the differential expression of BmCarE gene （bmcare） in the midguts, and the ability of Bombyx mori resistant to densonucleosis virus （BmDNV）, and to elucidate the molecular mechanism of resistance to BmDNV-Z. With two silkworm strains, HUABA, which is susceptible to BmDNV-Z, and BC8 （a near isogenic line of HUABA）, which is completely resistant to the same virus, as materials, the activity of BmCarE in the midgut was determined by Bio-Tek Synergy, and the differential expression of bmcare between the two strains was investigated by real-time fluorescence quantitative PCR, both at 12, 36, and 72 h post oral inoculation of the two strains with virus （hereafter referred as inoculation）. While the activity of BmCarE in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculated group, and the HUABA control group by 3.28, 2.26, and 3.02 times, respectively, with the difference being highly significant （P 〈 0.01）, there was no statistical difference among the other groups. The relative expression level of bmcare in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculation group, and the HUABA control group by 17.714, 21.76, and 15.09 times, respectively, with the difference being highly significant （P 〈 0.01）, and there was no statistical difference among other groups. The elevation of BmCarE activity and expression level of bmcare in the resistant strain at 12 h post inoculation may relate to the resistant gene （nsd/nsd） and the stimulation of BmDNV-Z. The molecular basis for the elevation of BmCarE activity in the resistant strain BC8 may be the change in the expression level of bmcare.     

马立克氏病病毒囊膜糖蛋白I原核表达产物单克隆抗体的制备

以重组质粒 p GEX-MDg I在大肠杆菌 BL2 1中表达马立克氏病病毒 (MDV)特超强毒 64 8A株的囊膜糖蛋白 I(g I)完整基因 ,通过 SDS-聚丙烯酰胺凝胶电泳分离相应的蛋白条带 ,切下并碾碎后作为免疫原免疫小鼠 ,用以制备针对MDV64 8A g I糖蛋白的杂交瘤细胞株。以 MDV感染的鸡胚成纤维细胞 (CEF)为检测抗原 ,用间接免疫荧光抗体反应(IFA)筛选到 9株杂交瘤细胞株 ,选其中 3株 2 H7、6F1 0、2 H3制备腹水 ,其 IFA效价均达到 1∶ 1 50 0以上 ;与 I型 MDV不同致病型的毒株 CVI988/ Rispens、GA、RB1 B、Md1 1株感染的 CEF测 IFA,均呈现特异性荧光 ,但反应强度不同。腹水经 PBS稀释后与 MDV感染的 CEF做斑点酶联免疫吸附试验 ,呈特异性显色。对 MDV感染的 CEF裂解物做 West-ern-blotting,可检测出 1条特异性条带     

Ⅰ型马立克氏病强弱毒株Meq基因的克隆与序列分析

[目的]为获得MDV-1强弱毒株Meq基因序列的差异。[方法]根据GENE BANK登录的马立克氏病毒Meq基因序列,设计一对引物,采用PcR技术对MDV—Ⅰ型国内商用CVI988／Rispens疫苗株和参考强毒京-1（BJ-1）株的Meq基因进行了扩增,并将扩增产物提纯后克隆到pcDNA3．1（＋）上,进行酶切鉴定及测序验证。[结果]CVI988疫苗株和BJ-1强毒株的Meq基因开放阅读框（ORF）长度分别为1200和1197bp。通过与国际标准强毒GA株Meq基因进行比较,BJ-1株和CVI988株Meq基因中分别有一段180和177bp的插入序列,第211住核苷酸由G变为T,导致第71位氨基酸由丙氨酸A变为丝氨酸S;同时,CVI988株Meq基因第228位核苷酸由A变为G,导致第77位氨基酸由赖氨酸K变为谷氨酸E。此外,与BJ-1株相比,CVI988株Meq基因在576～578bp之间缺失3个碱基（ACC）,并导致第193位脯氨酸P的缺失,该突变发生在一个多脯氨酸重复区域内。[结论]MDV-1强弱毒株Meq基因序列存在明显差异,为从其分子水平进行区分及生物学功能的研究奠定了基础。     

MDV CVI988/Rispens弱毒株VP22基因克隆和序列分析

血清I型马立克氏病病毒(MDV-1)的UL49h基因编码病毒被膜蛋白VP22在病毒的复制和传播过程中具有非常重要的作用.根据已发表的MDV-1 GA株的序列,从CVI988/Rispens弱毒株感染的鸭胚成纤维细胞中扩增VP22基因片段,结果获得大小为732 bp的PCR产物.将PCR产物克隆T载体并测序分析,结果发现,与经典强毒GA株相比,弱毒株CVI988的VP22存在3个定点突变和一个缺失性突变.缺失的位点亲水性强,并位于VP22主要的抗原决定簇区.结果证明强毒株与弱毒株的VP22存在明显差异,为利用CVI988 VP22的蛋白传导域传导目的蛋白奠定了理论基础.     

重组马立克病病毒CVI988/Rispens的构建

根据Ⅰ型马立克病病毒（MDV）强毒GA株基因序列,设计两对引物,用PCR方法扩增出CV1988／Rispens株的US10及其侧翼序列,分别克隆入pUC18载体中。经测序检测正确后,进一步插入含CMV启动子的绿色荧光蛋白（EGFP）基因表达盒,获得了含EGFP报告基因的转移载体质粒pPUC18-US10-EGFP。通过同源重组,成功地筛选出表达EGFP的重组病毒rCV1988-EGFP,经传代证明重组rCV1988-EGFP在感染的CEF细胞中能稳定表达EGFP。结果表明：构建的重组转移载体质粒正确,US10是MDV复制非必需片段,为进一步利用US10区构建重组MDV多价基因工程疫苗奠定了基础。     

表达NDV F48E9株F基因的MDV CVI988株转移质粒载体的构建

将新城疫病毒(NDV)F48E9株融合蛋白(F)基因1700bp克隆到真核表达载体pIRES中,构建成表达F基因的载体pIRESF,然后将包含F基因及其上游的内含子和下游的polyA的2900bpDNA片段再克隆入包含gB启动子的SK载体中,并使其克隆到gB启动子600bp的下游,最后将包含gB启动子和F基因表达盒3500bp克隆到包含MDVCVI988非必须片段US10的载体SK中。该研究为进一步在细胞中转染并获得表达F基因的MDVCVI988重组病毒奠定了基础。     

PRV FB弱毒株与FA株gE,gI基因的同源性研究

用PCR方法扩增了PRVFB弱毒株和PRVFA野毒株的gE,gI基因,对FB弱毒株的gE,gI基因进行克隆和测序,并将其与GenBank中收录的PRVFA的gE,gI基因进行了比较。结果发现,PRVFB和PRVFA株的gE基因有2处碱基发生了点突变,同源性为99%;gI基因有7处碱基发生了突变,其中1处发生了3个碱基的插入突变,同源性为98%。表明PRVFB在传代过程中发生了遗传性变异。     

接种不同毒力马立克氏病毒对鸡端粒酶活性和致病性的影响

以MDV京-1株和GA株诱发的MD为肿瘤模型,跟踪测定了鸡生长过程中脾脏组织的端粒酶活性变化。结果表明,端粒酶活性在没有临床症状和可视病变出现之前便可检测到。随着MDV感染日龄的增加逐渐升高,在其相对活力达到最高值后,总体水平略有下降,但依然存在端粒酶活性;而疫苗株CVI988接种后,整个生长过程其端粒酶均呈阴性。发生MD病变的鸡生长迟缓,中枢性免疫器官胸腺和法式囊严重萎缩,并出现体内肿瘤。无论是病变程度,还是死亡个数和时间,京-1株的致病性均高于GA株。     

含E.coli F因子的马立克氏病病毒1型（MDV1）转移载体的构建及初步应用

【目的】为了构建MDV1细菌人工染色体，以便快速有效地进行重组病毒的筛选，进行了含E.coli F因子的马立克氏病病毒1型（MDV1）转移载体的构建。【方法】利用DNA重组技术，构建了含有E.coli F因子的马立克氏病病毒1型（MDV1）转移载体，利用脂质体，将线性化的转移载体转染入已感染CVI988病毒的CEF，用MX-HAT药物筛选3代以后，用X-gal染色,挑取阳性克隆。【结果】经测序分析发现，人工体外合成的单一loxP位点，序列正确，另外，同源重组左臂和右臂序列正确，并且相对连接。利用SphⅠ和NheⅠ双酶切，鉴定出含有同向LoxP位点的转移载体，将其命名为pUS-BGS。将该载体用NheⅠ线性化后，用脂质体转染已感染CVI988病毒的CEF，用MX-HAT药物筛选3代以后，X-gal染色，可以观察到呈现蓝色的重组病毒。【结论】本研究报道了含有E.coli F因子以及两同向的loxP位点的MDV1转移载体的构建，利用该载体可以有效地进行重组病毒的筛选，为下一步MDV1细菌人工染色体的构建奠定了基础。     

鸡马立克氏病的免疫形态学研究

为了比较马立克氏病(MD)弱毒苗814鸡胚免疫与雏鸡免疫的免疫保护力。检查其鸡胚免疫的安全性,探索MD的免疫性质和免疫发生规律。本实验应用组织学和组织化学的方法,分别对18只龄鸡胚免疫鸡。1日龄雏鸡免疫鸡和非免疫对照鸡不同时期MD强毒攻击后的病理变化进行了检查。并对各组未攻毒鸡的胸腺、法氏囊、脾脏、盲肠扁桃体、肺脏和肝脏进行了动态观察。对各组淋巴器官的T、B淋巴细胞和巨噬细胞进行了统计比较,实验结果表明:MD弱毒苗814鸡胚免疫与雏鸡免疫比较,能促进免疫器官的早期发育,提前获得免疫保护力,MD弱毒苗814鸡胚免疫不引起MD病变,是安全的:MD免疫以T淋巴细胞为主,同时B淋巴细胞和巨噬细胞积极参与。     

鸡马立克氏病疫苗不同接种途径对免疫效果的影响

用 CVI988+HVT二价细胞结合苗分别以气雾、点眼、滴鼻、皮下注射 4种不同途径免疫 1日龄雏鸡 ,另设一组鸡作为非免疫对照组 .免疫后第 8d,每组鸡均用 MDVBJ- 1强毒攻击 ,气雾、点眼、滴鼻和皮下注射免疫保护指数分别为 7.89%、7.30 %、9.19%和 6 7.0 2 % .皮下注射免疫组与其他免疫组之间差异极显著 (P<0 .0 1) ;气雾、点眼、滴鼻以及非免疫对照组之间差异不显著 (P>0 .0 5) .结果表明皮下注射免疫组的免疫效果最好 .