嗜线虫致病杆菌北京变种CB6菌株杀虫蛋白对棉铃虫幼虫的生物活性

嗜线虫致病杆菌北京变种Xenorhabdus var.pekingensis CB6菌株是本研究室自主分离的新菌株,其代谢物对棉铃虫具有很强的拒食和抑制生长活性.为了进一步明确代谢物中杀虫蛋白的生物活性,作者用饲料染毒法和叶碟法测定了杀虫蛋白对棉铃虫不同龄期幼虫取食和生长发育的影响.结果表明,杀虫蛋白对棉铃虫幼虫有很强的抑制生长作用,用64μg/g含杀虫蛋白饲料饲喂初孵、1、2和3龄幼虫5天的生长抑制率分别达95.37%、92.73%、87.15%和88.64%,并明显延长幼虫发育历期,影响幼虫的化蛹及蛹的羽化.杀虫蛋白对5龄棉铃虫幼虫拒食效果明显,幼虫饲喂经1.6mg/mL杀虫蛋白处理的叶片24h,选择性拒食率和非选择性拒食率分别为76.22%和85.42%.当蛋白浓度为0.32mg/mL时,24h选择性拒食和非选择性拒食率分别为68.39%和74.75%.     

棉铃虫齿唇姬蜂寄主识别行为的研究

棉铃虫齿唇姬蜂室内寄生行为观察发现，无选择条件下，处女蜂对棉铃虫和斜纹夜蛾幼虫的寄生偏爱强于甜菜夜蛾，第3次遭遇，雌蜂对棉铃虫、斜纹夜蛾和甜菜夜蛾幼虫的累计产卵刺探率分别为73．3％、70％和30％；产卵经历能显著增强雌蜂对最优寄主和次优寄主的寄生能力；雌蜂不具同种识别过寄生能力，具一定自身识别过寄生能力，但时效期短于8h。雌蜂对混合种群的寄生选择研究发现，寄生蜂对斜纹夜蛾幼虫的寄生率显著高于甜菜夜蛾幼虫，分别为91．0％和76．3％；雌蜂对3日龄、4日龄和5日龄斜纹夜蛾幼虫的寄生率分别为71．7％、67．8％和63．4％，三者之间差异不显著，均显著高于对6日龄幼虫的寄生率（30．4％）。     

印楝素A和印楝素B生物活性比较

对印楝素A和印楝素B的生物活性进行了研究。在3μg/mL的剂量下处理后24 h,印楝素A和印楝素B对小菜蛾3龄幼虫的拒食率分别为85.3%和80.4%;在5μg/mL的剂量下处理后24 h,对棉铃虫3龄幼虫的拒食率分别为94.9%和80.2%。处理后72 h,印楝素A和印楝素B对斜纹夜蛾3龄幼虫的LC₅₀分别为1.0μg/mL和3.3μg/mL。印楝素A和印楝素B在3μg/mL的剂量下处理后72 h,小菜蛾3龄幼虫的死亡率分别为90.42%和84.11%;在5μg/mL的剂量下处理后72 h,棉铃虫3龄幼虫的死亡率分别为99.1%和100.0%;在0.5μg/mL的剂量下处理后72 h,斜纹夜蛾4龄幼虫体重降低率分别为57.5%和72.73%;在0.8μg/mL的剂量下处理后72 h,棉铃虫3龄幼虫体重降低率分别为84.1%和80.9%。     

昆虫病原线虫共生细菌发酵液对棉铃虫和菜青虫的口服毒性

研究了昆虫病原线虫共生细菌4个种和1组未定名种28个菌株发酵液对棉铃虫、菜青虫幼虫的致死、抑制生长和拒食作用。嗜线虫致病杆菌对棉铃虫幼虫具有较高的口服毒性，含20％(V／W)嗜线虫致病杆菌CBl2、CB6、CB5、CB28菌株发酵液的人工饲料饲喂棉铃虫初孵幼虫6天后，幼虫校正死亡率分别为97．7％、88．7％、88．4％和88．4％，饲喂棉铃虫3龄幼虫5天后，相对生长抑制率分别为96.4％、95．1％、95．6％和93．8％，上述菌株发酵原液涂抹白菜叶片饲喂5龄棉铃虫幼虫24h后相对拒食率分别为87．6％、83．6％、91．4％和89．8％；光杆状菌CBl、cBl52菌株、嗜线虫致病杆菌CB19菌株和波氏致病杆菌CB32菌株发酵原液涂抹白菜叶片饲喂菜青虫24h后，相对拒食率分别为82．7％、77．2％、75．8％和75．0％。     

植物精油对三种鳞翅目害虫的杀虫活性

测试了27种植物精油对粘虫、棉铃虫和小菜蛾的杀虫活性。结果表明:①用100倍精油丙酮液处理的小麦叶碟饲喂粘虫3龄幼虫48h后,砂地柏果实、玳玳花、甜橙果皮和姜根4种精油对试虫的拒食率均达80％以上;砂地柏果实、玳玳花、甜橙果皮等7种精油对粘虫4龄幼虫历期和蛹重均产生一定的影响,尤以砂地柏果实、玳玳花、甜橙果皮精油致幼虫死亡率最高,砂地柏果实和甜橙果皮精油对蛹重影响最为明显;②以含1％精油的人工饲料饲喂棉铃虫3龄幼虫9天后,山苍子果实、甜橙果皮精油处理组幼虫重量均仅为对照的20％左右,且各精油对幼虫历期、蛹重和化蛹率均有一定的影响;③八角茴香果实精油对小菜蛾的拒食活性达59.1％以上。     

非洲山毛豆对菜粉蝶化蛹的影响

非洲山毛豆Tephrosia vogelii Hook丙酮提取物点滴处理菜粉蝶Pieris ropae L.5龄幼虫和蛹后,出现6种不同症状的畸形蛹。50倍丙酮提取物点滴5龄前期(蜕皮后1～8h)幼虫后,74.4％出现死亡,25.6％未死幼虫均变为畸形蛹;处理5龄中后期幼虫时,绝大多数幼虫均在化蛹时出现畸形。     

棉铃虫齿唇姬蜂生物学特性及田间控制作用研究

棉铃虫齿唇姬蜂在河南新乡棉区年发生约8代,以6个世代发生在棉田,其中4个世代与棉铃虫低龄幼虫发生期吻合。田间出现4个寄生高峰,分别在5月中旬、6月中下旬,7月底至8月初,8月底至9月初,寄生率平均在19.2～42.9％,以一、二代棉铃虫期的寄生率较高,齿唇姬蜂对3龄前棉铃虫幼虫的总寄生率平均为23.7％,最高达40.0％,占整个世代总寄生数的71.3％。该蜂是豫北棉铃虫寄生性天敌中的优势种。成蜂对菊酯类农药敏感。     

荧光增白剂对Cry1Ac抗感棉铃虫围食膜的影响及增效作用

为了提高Bt的杀虫活性,运用扫描电镜、SDS-PAGE电泳和生物测定技术,研究了荧光增白剂FB28对棉铃虫Cry1Ac抗性和敏感品系围食膜的影响及对Cry1Ac杀虫蛋白的增效作用。结果表明,正常棉铃虫围食膜表面光滑致密,没有空洞和缝隙。用含1%FB28的人工饲料饲喂刚蜕皮的5龄棉铃虫幼虫2 h后,抗感棉铃虫围食膜表面均出现许多空洞,且敏感棉铃虫的空洞明显大于抗性棉铃虫;随着处理时间的延长,围食膜上的空洞逐渐变小,13 h后恢复正常。用1%FB28离体或活体处理抗、感品系棉铃虫,均可造成围食膜蛋白被降解。用1%FB28与Cry1Ac杀虫蛋白混合饲喂抗、感棉铃虫初孵幼虫,可明显提高棉铃虫的死亡率,且对抗性品系的增效作用明显大于敏感品系,对敏感和抗性品系棉铃虫的增效比分别为2.23和9.34;1%FB28还可以明显增加对抗、感品系3龄棉铃虫幼虫的生长抑制作用。     

嗜线虫致病杆菌CB6菌株对小菜蛾幼虫生物活性的研究

用叶碟法测定了嗜线虫致病杆菌CB6菌株发酵液对小菜蛾幼虫的致死率、拒食活性以及对生长发育的影响。结果表明 ,其发酵液对幼虫有较高的生物活性 ,取食 3d后 ,1～3龄幼虫的校正死亡率分别为 84.75%、68.33%和 59.32%。 4龄幼虫取食量显著减少 ,选择性拒食率为 76.59% ,非选择性拒食率为 69.72%。 3龄幼虫取食发酵液处理的叶片后 ,生长极其缓慢 ,在 48h时体重抑制率达 100% ,化蛹率和羽化率均明显下降 ,其中化蛹率仅为 15.56% ,100%蛹不能羽化。     

溪岸蠼螋对棉铃虫的捕食能力

为明确棉田溪岸蠼螋 Labidura riparia 对棉铃虫的控害潜能, 在实验室条件下观察和测定了溪岸蠼螋不同龄期的若虫、雌雄成虫对棉铃虫幼虫、蛹和成虫的捕食能力以及其5龄若虫和雌雄成虫的捕食选择性。结果表明:不同发育阶段的溪岸蠼螋都不捕食棉铃虫完整的蛹体, 但对棉铃虫幼虫和成虫都具有较强的捕食能力。其中, 雌性溪岸蠼螋成虫的捕食能力最强, 对棉铃虫1龄幼虫日捕食量最大, 为(31.3±1.1)头。1龄溪岸蠼螋若虫也具有一定的捕食能力, 对棉铃虫1龄幼虫日捕食量为(1.7±0.7)头。不同龄期的溪岸蠼螋对相同龄期棉铃虫幼虫的捕食能力随龄期增加而增大。对1~3龄棉铃虫幼虫,溪岸蠼螋雌成虫捕食能力最强,其次是溪岸蠼螋雄成虫,再次是溪岸蠼螋5龄若虫。但是,对棉铃虫4~6龄幼虫和雌雄成虫,溪岸蠼螋雌雄成虫和5龄若虫的捕食量差异不显著。捕食选择试验表明:溪岸蠼螋5龄若虫和雌雄成虫对棉铃虫1～4龄幼虫均表现正喜好性, 对5～6龄棉铃虫幼虫和雌雄成虫表现负喜好性。     

Tick repellents: Past, present, and future

Ticks are important vectors of human and animal diseases. One important protective measure against ticks is the use of personal arthropod repellents. Deet and the synthetic pyrethroid permethrin currently serve as the primary personal protective measures against ticks. Concern over the safety of deet and its low repellency against some tick species has led to a search for new user-approved, efficacious tick repellents. In this article, we review the history and efficacy of tick repellents, discovery of new repellents, and areas in need of attention such as assay methodology, repellent formulation, and the lack of information about the physiology of repellency.     

Trichoderma: systematics, the sexual state, and ecology

ABSTRACT A chronology is presented that charts the development of a genus and species concept in Trichoderma. Eighty-nine species of Trichoderma have been named, and several species of Hypocrea have been linked to unnamed Trichoderma anamorphs. Eighty-three taxa of Trichoderma and their teleomorphs, Hypocrea spp., have been included in phylogenetic analyses, including 11 species of Hypocrea with unnamed Trichoderma anamorphs. Phylogenetic analyses show that Trichoderma and Hypocrea are congeneric. Trichoderma species not linked to Hypocrea teleomorphs are derived from among species that are linked to teleomorphs, indicating sexual and asexual lineages are not independent of each other. Many more species remain to be discovered and described. Molecular phylogenetic analyses have revealed the existence of more species than have been recognized on the basis of morphology alone. A suggestion is made to modify the International Code of Botanical Nomenclature to enable adoption of a single generic name for Trichoderma/Hypocrea, with Trichoderma being the older and more utilitarian name. As increasing numbers of species are studied, the few morphological characters of anamorph and teleomorph have reached their limit for defining species. DNA-based characters have assumed an indispensable role. Exploration of new niches, such as within tree trunks and new geographic locations, have resulted in a substantial increase in the number of species of Trichoderma. Trichoderma is usually considered a genus of free-living soil fungi but evidence suggests that Trichoderma species may be opportunistic, avirulent plant symbionts as well as parasites of other fungi. Members of the genus Trichoderma are universally present in soils, although individual species may be either cosmopolitan (e.g., T. harzianum) or limited (e.g., T. viride) in their geographic distribution. To facilitate identification of species, a list of correctly identified strains of Trichoderma and their GenBank numbers for sequences of translation-elongation factor EF-1alpha and internal transcribed spacer rDNA is provided.     

Pesticide soil sorption parameters: theory, measurement, uses, limitations and reliability

The soil sorption coefficient Kd and the soil organic carbon sorption coefficient KOC of pesticides are basic parameters used by environmental scientists and regulatory agencies worldwide in describing the environmental fate and behavior of pesticides. They are a measure of the strength of sorption of pesticides to soils and other geosorbent surfaces at the water/solid interface, and are thus directly related to both environmental mobility and persistence. KOC is regarded as a 'universal' parameter related to the hydrophobicity of the pesticide molecule, which applies to a given pesticide in all soils. This assumption is known to be inexact, but it is used in this way in modeling and estimating risk for pesticide leaching and runoff. In this report we examine the theory, uses, measurement or estimation, limitations and reliability of these parameters and provide some 'rules of thumb' for the use of these parameters in describing the behavior and fate of pesticides in the environment, especially in analysis by modeling.     

Intestinal uptake,metabolism, and transport of naphthol: In vitro capacity,requirements, and inhibition

The metabolism and transport of [¹⁴C]-naphthol were investigated in sacs of rat small intestine to better understand metabolism of the pesticide carbaryl (which contains naphthol) in the intestine. The capacity to synthesize polar ¹⁴C-labeled metabolites was approximately saturated at 50 μM naphthol. The metabolic capacity of the cranial small intestine was about two times the capacity of the caudal. Anaerobic incubation severely suppressed naphthol metabolism. Sodiumfree medium suppressed metabolism only slightly but altered transport of water and of the polar ¹⁴C-labeled metabolites to serosal and mucosal fluids; the effect on metabolite transport cannot be explained by the effects of sodium on water movements, however. Calcium-free medium did not affect metabolism or metabolite transport; 2,4-dinitrophenol, and possibly phlorizin, but not ouabain, suppressed naphthol metabolism in specific regions of the intestine. Each of the three inhibitors altered metabolite transport. It is concluded that the capacity to conjugate naphthol in the small intestine is greater in the cranial than caudal regions; the quantity of naphthol taken up from the medium is proportional to the rate of formation of the polar metabolite, naphthyl glucuronide; addition of 2,4-dinitrophenol, phlorizin, or ouabain, or deletion of sodium, perturbed the transport of the polar metabolite, but the perturbance could not be explained by the effect on rate or direction of fluid transfer and indicated an effect on cellular permeability or on transport mechanisms; the effect of the three inhibitors and possibly of elevated naphthol concentrations (to 520 μM) in the medium on metabolite transport may be by a sodium interaction; the latter suggests that naphthol may be toxic to the intestine at concentrations approaching 100 to 1000 μM.     

Inside Cover: Cover Image,Volume 75, Issue 1

The inside cover image is based on the Research Article Carfentrazone‐ethyl and glyphosate drift inhibits uredinial formation of Austropuccinia psidii on Eucalyptus grandis leaves by Samuel Alves dos Santos et al., DOI: 10.1002/ps.5163 .

     

Back Cover: Cover Image,Volume 74, Issue 9

The back cover image, by Victor R. Aguilar, is based on the Mini‐Review by Robert D Clark, Predicting mammalian metabolism and toxicity of pesticides in silico, DOI: 10.1002/ps.4935 .

     

Front Cover: Cover Image,Volume 74, Issue 9

The front cover image, by Rodrigo Krugner and Shira D. Gordon, is based on the Research Article Mating disruption of Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae) by playback of vibrational signals in vineyard trellis, DOI: 10.1002/ps.4930 .

     

环境成本研究: 合作、演进、热点及展望——基于CitespaceV的可视化分析

梳理1992-2018年中国学术期刊网络出版总库(CNKI)收录的关于环境成本研究的相关文献,借助信息可视化软件CitespaceⅤ绘制科学知识图谱。通过环境成本作者合作网络,关键词聚类图谱、时区图谱、突现词检测,真实、立体、全面考察环境成本的研究背景、梳理演化路径、挖掘研究前沿。研究发现:1)研究群体呈现大分散、小集中的特点,核心学者间形成学术共同体;2)研究机构集中在高校,为环境成本研究提供实质性资源与智慧支持;3)研究经历了萌芽、发展、成熟三个进程,主要围绕环境成本核算、企业环境成本会计、行业环境成本展开;4)低碳经济、价值链、多目标优化、全成本、微电网、稀土、风电成为近几年高曝光的热门词频。在低碳经济这一新型经济发展模式指导下,核算是环境成本研究的不变主题,清洁生产是未来环境成本研究的主导方向。     

Front Cover: Cover Image,Volume 75, Issue 1

The front cover image is based on the Research Article Projecting the current and future potential global distribution of Hyphantria cunea (Lepidoptera: Arctiidae) using CLIMEX by Xuezhen Ge et al., DOI: 10.1002/ps.5083 . Photo Credit: Lili Ren

     

Back Cover: Cover Image,Volume 75, Issue 1

The back‐cover image is based on the Research Article Successful management of Halyomorpha halys (Hemiptera: Pentatomidae) in commercial apple orchards with an attract‐and‐kill strategy by William R Morrison et al., DOI: 10.1002/ps.5156 . Photo Credit: Rob Morrison, Ph.D.