曲霉发酵液对烟草根结线虫的作用

室内测定了一株曲霉发酵液对烟草根结线虫优势种群南方根结线虫（Meloidogyne incognita）2龄幼虫、卵囊和散卵粒孵化的影响。不同稀释浓度发酵液的处理和无菌水处理有显著差异，发酵液的1倍液以上浓度与10μtg／ml涕灭威的防效相当，对2龄幼虫的致死率在90％以上，对卵囊和散卵粒孵化的抑制率在95％以上。     

Determination and Analysis of Ustiloxins A and B by LC-ESI-MS and HPLC in False Smut Balls of Rice

Ustiloxins are cyclopeptide mycotoxins produced by the pathogenic fungus Villosiclava virens of rice false smut. Ustiloxins A and B as two main mycotoxins were determined conveniently by LC-ESI-MS in the water extract from rice false smut balls which were mostly composed of the chlamydospores and mycelia of the pathogen. Both ustiloxins A and B in the water extract were also quantitatively analyzed by HPLC. This is the first report on the determination and analysis of ustiloxins A and B simultaneously by LC-ESI-MS and HPLC in false smut balls of rice.     

6种常用农药与球孢白僵菌和蜡蚧轮枝菌的相容性

测定了3种杀虫剂和3种杀菌剂在田间常规浓度下对球孢白僵菌和蜡蚧轮枝菌孢子萌发和菌丝生长的影响。供试杀虫剂对球孢白僵菌孢子萌发的影响很小，萌发率超过85％，对蜡蚧轮枝菌孢子萌发影响较大，抑制作用最小的吡虫啉，抑制率达到25％。3种杀菌剂几乎完全抑制了孢子的萌发。杀虫剂对球孢白僵菌的菌丝生长有一定抑制作用，抑制率为22．60％-38．39％；对蜡蚧轮枝菌菌丝生长的影响小于对球孢白僵菌的影响，抑制率为10．06％．17．61％。供试杀菌剂对球孢向僵菌和蜡蚧轮枝菌菌丝生长的抑制作用都较大，抑制率都在50％以上。     

幂指数模型模拟玉米弯孢菌叶斑病传播梯度的试验

采用人工接种方法，在田间造成玉米弯孢菌叶斑病不同的发病梯度。利用SAS统计软件构建了该病害传播梯度的幂指数模型，结果表明幂指数模型可以模拟该病害传播动态，同时推导该病害在一个月最远传播距离为16m，两个月最远传播距离为28m。     

草原蝗虫防治药剂的室内筛选

[目的]蝗虫对草原危害很严重,多年的化学防治对常规药剂产生了抗性,寻找高效低毒药剂很有必要。[方法]以氯虫苯甲酰胺等11种杀虫剂为材料,采用浸渍叶片法对华北雏蝗和宽须蚁蝗3龄若虫进行了室内毒力测定。[结果]丁虫腈、氯虫苯甲酰胺、甲维盐、氟虫腈对华北雏蝗和宽须蚁蝗均表现出较强毒力,氟虫腈对华北雏蝗的毒力最高(LC50值为0.14 mg/L),毒死蜱对华北雏蝗的毒力最低(LC50值为12.31 mg/L),丁虫腈对宽须蚁蝗的毒力最高(LC50值为0.11 mg/L),毒死蜱对宽须蚁蝗的毒力最低(LC50值为13.99 mg/L)。[结论]11种药剂对华北雏蝗和宽须蚁蝗毒力的差异,可用于防治以上2种蝗虫高效低毒药剂的筛选。     

Effect of hydroxyl and Mo doping on activity and carbon deposition resistance of hydroxyapatite supported NixMoy catalyst for syngas production via DRM reaction

The doping of the second metal Mo is expected to further enhance the carbon deposition resistance of Ni-based catalysts for syngas production via dry reforming of methane (DRM). In this study, the hydroxyapatite (HAP) was used as the support and a small Mo dosage was doped in the Ni-based catalysts to investigate the effect of intrinsic hydroxyl and Mo doping on the catalytic activity and carbon deposition resistance in DRM reaction. The catalyst characterization results show that both Ni and Mo are doped into the HAP structure with relatively uniform dispersion. The basic site strength of Ni4Mo0.2-HAP catalyst containing Mo is significantly higher than that of without Mo. The Mo dopant significantly improves the initial catalytic activity, but has minimal effect on the stability enhancement. Whether the catalyst is pre-reduced or not is crucial to the initial activity of the DRM reaction, the non-pre-reduced catalysts will go through a “self-activation” stage at the beginning of the reaction, where the “hydroxyl group” are proved to play as an “oxygen supply” for the partial oxidation of CH₄ or the oxidation of the carbon deposition in the initial stage. Only trace amount of carbon deposition is found after 100 h of DRM reaction on Ni3Mo0.2-HAP catalyst. The NiMo-HAP catalysts exhibit excellent initial activity and resistance to carbon deposition due to the synergistic effect of Ni–Mo alloy and hydroxyl groups in the hydroxyapatite support.     

响应面法优化Streptomyces albus B-215菌发酵产ε-PL的培养基成分

通过响应面法建立模型,分析优化了对Streptomyces albus B-215发酵产ε-聚赖氨酸的培养基成分,得到的优化结果为:葡萄糖55.50g/L,硫酸铵12.25g/L,磷酸二氢钾1.72g/L,酵母膏7.80g/L,装液量50mL/500mL,pH值为7,接种量10％,转速180r/min.在此最佳条件下,ε-PL产量为0.948g/L.验证试验表明试验模型准确、可靠.     

野稷对烟嘧磺隆的抗性水平及抗性机制

[目的]明确辽宁省野稷对烟嘧磺隆的抗性水平及抗药性机制.[方法]采用整株生测法测定不同种群对烟嘧磺隆的抗药性水平及细胞色素P450s活性差异,并通过对野稷ALS序列片段进行扩增测序,研究ALS序列差异.[结果]采自辽宁省阜新市的种群R-3呈高等水平抗药性,GR50值为80.58 g a.i./hm2,抗性指数达22.2...     

两株根际促生细菌对TMV的生防作用研究

烟草花叶病毒（Tobacco mosaic virus,TMV）是危害烟草的主要病毒之一,其寄主范围广、侵染力和抗逆性强,尚无有效的抗病毒药剂。利用植物根际促生细菌（PGPR）对寄主的促生以及对病毒的钝化作用进行病毒病早期预防,是控制TMV的有效途径。本文对筛选到的两株PGPR菌株Sa和Sk进行了菌株鉴定及促生和防病作用研究。结果表明:Sa为芽孢杆菌属（Bacillus sp.）、Sk为假单胞菌属（Pseudomonas sp.）。在霍格兰氏营养液中添加Sa、Sk的发酵上清液,能显著促进烟苗的根系发育和茎叶生长;“半叶法”试验结果显示Sa、Sk的发酵上清液能在体外钝化TMV,并且Sa的粗蛋白溶液、去蛋白上清、蛋白失活后的粗蛋白溶液对TMV的抑制效果分别为85.2%、83.1%、36.2%,说明Sa的发酵物中对TMV起钝化作用的活性物质主要包括蛋白和非蛋白两类;Sk的粗蛋白溶液、去蛋白上清抑制TMV的效果分别为88.0%、0%,说明Sk的发酵物中对TMV起钝化作用的活性物质主要为蛋白类。利用TMV30B侵染性克隆,观察到Sa、Sk发酵上清液能显著抑制病毒的初侵染。室内栽培烟株喷施Sa、Sk发酵上清后,对TMV的防效分别为27.71%和18.55%。芽孢杆菌Sa生防效果好于Sk,具备抗病毒剂的开发潜力。