植物提取物对黄曲条跳甲成虫毒杀作用的研究

研究24种植物提取物对黄曲条跳甲成虫的毒杀活性。结果表明：处理后72h,供试植物提取物中的7种对黄曲条跳甲成虫有毒杀作用,但毒杀活性较低,其中烟碱对黄曲条跳甲成虫的毒杀效果最好,累积死亡率为3．33％;假莲翘Duranta repeens乙醇提取物对黄曲条跳甲成虫的毒杀效果最差,累积死亡率为1．21％;其余提取物对黄曲条跳甲成虫的毒杀效果居中,累积死亡率为1．67％-2．78％。因此,毒杀作用并不是供试植物提取物对黄曲条跳甲成虫的主要控制机理。     

马缨丹提取物对黄曲条跳甲成虫的生物活性

测定了马缨丹(Lantana camaraL.)地上部位(茎叶花)的不同溶剂提取物及萃取物对黄曲条跳甲Phyllotreta striolata(Fabricius)成虫的取食忌避、拒食、胃毒和触杀作用。结果表明:处理后48 h,以马缨丹乙醇回流提取物效果最好,其对黄曲条跳甲成虫的取食忌避率达94.94%;非选择性拒食率为85.48%;除正丁醇萃取物对黄曲条跳甲成虫的胃毒作用达到56.67%外,其它处理对黄曲条跳甲成虫的胃毒作用不明显;石油醚萃取物、石油醚冷浸物、乙醇回流物对黄曲条跳甲成虫的触杀作用效果最好,分别为56.67,53.33和53.33%。据实验结果可知马缨丹不同溶剂提取物及萃取物对黄曲条跳甲成虫的生物活性主要表现在对成虫较强的忌避和拒食作用。     

植物提取物对黄曲条跳甲成虫毒作用的研究

研究24种植物提取物对黄曲条跳甲成虫的毒杀活性.结果表明处理后72h,供试植物提取物中的7种对黄曲条跳甲成虫有毒作用,但毒杀活性较低,其中烟碱对黄曲条跳甲成虫的毒杀效果最好,累积死亡率为3.33%;假莲翘Duranta repens 乙醇得取物对黄曲条跳甲成虫的毒杀效果最差,累积死亡率为1.12%;其余提取物对黄曲条跳甲成虫的毒杀效果居中,累积死亡率为1.67%-2.78%.因此,毒杀作用并不是供试植物提取物对黄曲条跳甲成虫的主要控制机理.     

黄曲条跳甲食性的研究

黄曲条跳甲 (Ｐｈｙｌｌｏｔｒｅｔａｓｔｒｉｏｌａｔａ (Ｆａｂｒｉｃｉｕｓ) )是十字花科植物的重要害虫。据文献记载 ,黄曲条跳甲除为害十字花科植物外 ,还取食茄科(Ｓｏｌａｎａｃｅａｅ)、豆科 (Ｌｅｇｕｍｉｎｏｓａｌｅｓ)、葫芦科 (Ｃｕｃｕｒ ｂｉｔａｃｅａｅ)、禾本科 (Ｇｒａｍｉｎｚｌｅｓ)等植物[1,2 ,4 ,5] 。取食范围如此之广 ,应为多食性 (ｐｏｌｙｐｈａｇｏｕｓ)昆虫。本文拟采用十字花科的近缘科及上述各科植物对黄曲条跳甲进行非选择性取食试验 ,以确定黄曲条跳甲的食性范围。1　材料和方法1.1　供试植物甘蓝 (Ｂｒａ…     

八种植物提取物对蔬菜害虫的室内毒力研究

研究了巴豆 (Croton tiglium L.)等八种植物的提取物对几种常见蔬菜害虫的非选择性拒食和毒杀作用。研究结果表明 :巴豆、青蒿、米仔兰等三种植物提取物在 0 .5 %浓度时对菜粉蝶 5龄幼虫的拒食率分别达到96 .36 %、82 .4 2 %和 86 .30 % ,对菜粉蝶 3龄幼虫的毒杀死亡率分别为 5 9.38%、2 8.1 3%和 4 3.75 % ;对黄曲条跳甲成虫的毒杀死亡率为 77.5 0 %、5 6 .2 5 %和 4 8.75 % ;对美洲斑潜蝇幼虫的毒杀死亡率分别为 83.33%、5 6 .6 7%和 73.33%。     

马缨丹乳油及其混剂对黄曲条跳甲的拒食活性

测试了自制的12.5%马缨丹乳油对黄曲条跳甲成虫拒食活性、持效性及其与7.5%鱼藤酮乳油、1.5%除虫菊水乳剂、0.3%印楝乳油混配的联合活性。该乳油1000倍液处理菜心叶片后48h对黄曲条跳甲成虫具有40%的拒食率,随着浓度升高,拒食活性增强;200、400和600倍液处理120h后对黄曲条跳甲成虫的累计拒食率分别达到76%、68%和43%。12.5%马缨丹乳油与7.5%鱼藤酮乳油以5∶5比例混配使用时,增效作用最为明显,拒食中浓度AFC50为5.25μg.ml-1,共毒系数CTC为213;与1.5%除虫菊水乳剂以1∶9比例混配使用时的增效作用次之,共毒系数CTC为149;与0.3%印楝乳油以9∶1、7∶3、5∶5、3∶7和1∶9比例混配使用时,其共毒系数CTC均100,表现为相互拮抗作用。结果表明:12.5%马缨丹乳油对黄曲条跳甲成虫具有强烈的拒食活性,其200倍液和400倍液拒食持效性好,且该乳油可与7.5%鱼藤酮乳油混配使用。     

虫害诱导的植株对小菜蛾取食和生长发育的影响

本文从菜田生态系统的角度出发,就黄曲条跳甲Phyllotreta striolata(Fabricius)取食诱导对小菜蛾Plutella xylostella(L.)造成的影响进行了研究。黄曲条跳甲取食诱导对小菜蛾取食的影响比较明显,一般来说,黄曲条跳甲少量或短时间的取食会刺激小菜蛾幼虫在相应叶片上的取食,反之则会抑制;而且不同的寄主,不同完整度的叶片(即是否被黄曲条跳甲取食过)上的承载能力不同,芥菜、白菜、菜心和萝卜的承载力弱于甘蓝和芥蓝,黄曲条跳甲取食过的叶片弱于未被黄曲条跳甲取食过的叶片;不同数量的黄曲条跳甲取食对小菜蛾的产卵量影响显著,对其余生物学参数影响不显著,少量的黄曲条跳甲取食会刺激小菜蛾的产卵,多数则会抑制。     

黄曲条跳甲田间种群发生的生态干扰

利用黄板诱集方法,监测黄曲条跳甲（Phyllotreta striolata）田间成虫的数量动态,发现该虫在福州全年均可发生危害,没有明显的越冬现象。2002～2003年共出现4个较为明显的成虫发生高峰和3个明显的成虫数量低谷。田间成虫数量与降雨、气温的相关分析表明,黄曲条跳甲的成虫发生与降雨、气温的关系不显著,但受到降雨、气温的复合作用。黄曲条跳甲成虫在不同寄主上的发生量存在明显的差异,数量变化在一茬菜的生长过程中也不同。黄曲条跳甲成虫对寄主具有明显的选择作用。     

非嗜食植物次生物质对小菜蛾产卵驱避和拒食作用的研究

基于植物与昆虫的协同进化理论,利用25科37种小菜蛾非嗜食植物的茎、叶、花或根的乙醇提取物,研究其对小菜蛾成虫的产卵驱避作用和对幼虫的拒食作用。结果表明,供试植物提取物对小菜蛾有不同程度的产卵驱避和拒食效果,羊蹄甲、细叶桉、飞扬草、假连翘、花椒、荷花玉兰、烟草的乙醇提取物对小菜蛾成虫产卵有较好的驱避效果,驱避率均达80％以上,一品红、构树、艾蒿、茶枯、垂柳、飞扬草、羊蹄甲、狗尾草的乙醇提取物对小菜蛾幼虫有较好的拒食作用,48h的拒食率达80％以上。     

基于Solexa高通量测序的黄曲条跳甲转录组学研究

黄曲条跳甲Phyllotreta striolata (Fabricius) 是十字花科蔬菜的重要害虫。为深入了解其遗传信息, 本研究应用新一代高通量测序技术Illumina’s Solexa平台对黄曲条跳甲成虫的转录组进行测序, 并结合SOAPdenovo拼接聚类等分析软件, 获取大量的EST和挖掘功能基因。本文最终获得了4 924条序列重叠群（contig）, 其中包含2 209种与黑腹果蝇Drosophila melanogaster蛋白基因具直系同源的独立基因（unigene）和610种黄曲条跳甲物种特有的unigene。结合Gene Ontology （GO）数据库进行分析, 发现大部分的unigene具结合能力（binding capability）和催化活性（catalytic activity）; 上百种unigene可聚类于生物学过程分类中的配子发生、 生殖腺发育和交配行为等重要功能。另外, 结合KEGG Pathway数据库分析发现, 共有363种unigene参与或涉及了40种代谢路径, 其中生物钟调控路径和植物次生代谢物路径等相关基因的发现, 有助于深入研究黄曲条跳甲行为发生的内在机理。Solexa高通量测序技术作为昆虫功能基因组研究的重要手段, 为发掘黄曲条跳甲功能基因发挥了重要作用, 也为在分子水平上研发黄曲条跳甲的防治新策略提供了更翔实的基因信息。     

Host plant choice experiments of Colorado potato beetle (Coleoptera: Chrysomelidae) in Virginia

Field and laboratory-choice experiments were conducted to understand aspects of host plant orientation by the Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae), in Virginia. In laboratory bioassays, L. decemlineata oriented to volatiles emitted by potato, Solanum tuberosum L., foliage over both tomato, Lycopersicon esculentum L., and eggplant, Solanum melongena L., foliage, and eggplant over tomato foliage, all of which had been mechanically damaged. Field choice tests revealed more L. decemlineata adults, larvae, and egg masses on eggplant than on tomato. In other experiments, counts of live L. decemlineata on untreated paired plants and counts of dead beetles on imidacloprid-treated plants did not differ between potato and eggplant. L. decemlineata was significantly attracted to eggplant over both tomato and pepper. To determine whether feeding adults affected orientation to host plants, an imidacloprid-treated eggplant or potato plant was paired with an untreated eggplant or potato plant covered in a mesh bag containing two adult male beetles. Significantly more adults were attracted to eggplant with feeding male beetles paired with another eggplant than any other treatment combination. These results indicate that the presence of male L. decemlineata on plants affects host plant orientation and suggests that the male-produced aggregation pheromone may be involved.     

Feeding Experience of Bemisia tabaci (Hemiptera: Aleyrodidae) Affects Their Performance on Different Host Plants

The sweetpotato whitefly, Bemisia tabaci biotype B is extremely polyphagous with >600 species of host plants. We hypothesized that previous experience of the whitefly on a given host plant affects their host selection and performance on the plants without previous experience. We investigated the host selection for feeding and oviposition of adults and development and survival of immatures of three host-plant-experienced populations of B. tabaci, namely Bemisia-eggplant, Bemisia-tomato and Bemisia-cucumber, on their experienced host plant and each of the three other plant species (eggplant, tomato, cucumber and pepper) without previous experience. We found that the influence of previous experience of the whiteflies varied among the populations. All populations refused pepper for feeding and oviposition, whereas the Bemisia-cucumber and the Bemisia-eggplant strongly preferred cucumber. Bemisia-tomato did not show strong preference to any of the three host palnts. Development time from egg to adult eclosion varied among the populations, being shortest on eggplant, longest on pepper, and intermediate on tomato and cucumber except for the Bemisia-cucumber developed similarly on tomato and pepper. The survivorship from egg to adult eclosion of all populations was highest on eggplant (80-98%), lowest on pepper (0-20%), and intermediate on tomato and cucumber. In conclusion, the effects of previous experience of whiteflies on host selection for feeding and oviposition, development, and survivorship varied depending on host plants, and host plants play a stronger role than previous experience. Preference of feeding and oviposition by adults may not accurately reflect host suitability of immatures. These results provided important information for understanding whitefly population dynamics and dispersal among different crop systems.     

不同寄主植物对马铃薯甲虫的引诱作用

随着马铃薯甲虫不断扩展其分布范围,其对寄主的适应性也在发生变化。在我国,马铃薯甲虫的主要寄主植物是马铃薯、茄子、番茄和天仙子。为进一步明确马铃薯甲虫对不同寄主植物的嗜食程度,研究了以上4种寄主植物对马铃薯甲虫的引诱作用,以及取食量的影响,同时进行了田间寄主选择性的调查。选择性试验结果表明:不同寄主植物对马铃薯甲虫的引诱作用差异显著,其中马铃薯、天仙子引诱作用显著高于茄子和番茄;取食量研究结果表明:马铃薯甲虫各龄期对不同寄主24 h取食量的大小依次为:马铃薯>茄子>天仙子>番茄;1—2龄幼虫取食量小,3—4龄幼虫及成虫暴食寄主叶片,是马铃薯甲虫造成危害的主要阶段。     

烟粉虱在烟株上的垂直分布及寄主选择性

烟粉虱是云南省农业生产上的重要害虫之一。通过田间系统调查和室内观察相结合,研究了烟粉虱在烟株上的垂直分布特性和在8种寄主作物上的取食、产卵趋性。（1）烟粉虱在烟株上的垂直分布特征为上部＞中部＞下部,8月中旬为种群高峰期,上、中、下部叶片的成虫密度分别为15．1、10．9、6．7头？片-1;（2）烟粉虱成虫的取食趋性表现为大豆＞南瓜＞甘薯＞番茄＞一品红＞茄子＞甘蓝＞烟草,各处理间差异不显著（P＞0．05）;（3）产卵趋性表现为一品红＞大豆＞南瓜＞甘薯＞番茄＞茄子＞甘蓝＞烟草,一品红与南瓜、甘蓝、茄子、甘薯、番茄、烟草处理间,以及大豆与烟草处理间存在显著差异（P＜0．05）,其他处理间差异不显著（P＞0．05）。在所测定的8种寄主植物中,烟粉虱成虫对烟草的选择性最差,烟区规划烟田种植范围时,应避免与大豆、南瓜、甘薯、番茄等作物间作或距离太近。     

Macrolophus pygmaeus (Hemiptera: Miridae) population parameters and biological characteristics when feeding on eggplant and tomato without prey

The population parameters and biological characteristics of the predator Macrolophus pygmaeus Rambur when feeding on eggplant, Solanum melongena L., and tomato, Lycopersicon esculentum (Miller) (both Solanaceae), without access to prey, were investigated at several temperatures. The experiments were conducted at 15, 20, 25, and 30 degrees C, 65 +/- 5% RH, and a photoperiod of 16:8 (L:D) h. Females oviposited on both plant species at all temperatures, with the exception of tomato at 30 degrees C. Fecundity was highest at 20 degrees C (21.55 and 8.28 eggs per female on eggplant and tomato, respectively). Adult longevity on both host plants was greatest at 15 degrees C, reaching 38.72 and 34.20 d for females and 92.88 and 62.80 d for males, on eggplant and tomato, respectively. The estimated values of population parameters showed that this predator increased its numbers on eggplant at all temperatures tested, but the highest intrinsic rate of increase occurred at 25 degrees C (0.0401 d(-1)). On tomato, this predator could not increase in number, although it could survive for a relatively long period. Results demonstrated that M. pygmaeus can survive on both host plants in periods of prey scarcity, particularly on eggplant. Therefore, phytophagy can positively contribute to the effectiveness of this biological control agent. The importance of eggplant as a reservoir for the predator in mixed crops that are less suitable host plants is discussed.     

Host feeding experience affects host plant odour preference of the polyphagous leafminer Liriomyza bryoniae

Herbivorous insects use highly specific volatiles or blends of volatiles characteristic to particular plant species to locate their host plants. Thus, data on olfactory preferences can be valuable in developing integrated pest management tools that deal with manipulation of pest insect behaviour. We examined host plant odour preferences of the tomato leafminer, Liriomyza bryoniae (Kaltenbach) (Diptera: Agromyzidae), which is an economically important agricultural pest widespread throughout Europe. The odour preferences of leafminers were tested in dependence of feeding experiences. We ranked host plant odours by their appeal to L. bryoniae based on two‐choice tests using a Y‐tube olfactometer with five host plants: tomato, Solanum lycopersicum Mill.; bittersweet, Solanum dulcamara L.; downy ground‐cherry, Physalis pubescens L. (all Solanaceae); white goosefoot, Chenopodium album L. (Chenopodiaceae); and dead nettle, Lamium album L. (Lamiaceae). The results imply that ranking of host plant odours by their attractiveness to L. bryoniae is complicated due to the influence of larval and adult feeding experiences. Without any feeding experience as an adult, L. bryoniae males showed a preference for the airflow with host plant odour vs. pure air, whereas females did not display a preference. Further tests revealed that adult feeding experience can alter the odour choice of L. bryoniae females. After feeding experience, females showed a preference for host plant odour vs. pure air. Feeding experience in the larval stage influenced the choice by adults of both sexes: for males as well as females reared on bittersweet the odour of that plant was the most attractive. Thus, host feeding experience both in larval and/or adult stage of polyphagous tomato leafminer L. bryoniae influences host plant odour preference by adults.     

B型烟粉虱对三种寄主植物及其挥发物的行为反应

利用Y型嗅觉仪,测定了B型烟粉虱Bemisia tabaci（Gennadius）雌虫对3种寄主植物、挥发物提取液、挥发物标样以及寄主植物挥发物模拟样的行为反应,并比较鉴定寄主植物挥发物的组分和含量,以期明确植物挥发物在B型烟粉虱寄主定向行为中的作用。结果表明：1）番茄植株和甘蓝植株及其相应的挥发物提取物对烟粉虱雌成虫均具有显著的引诱作用,而辣椒植株和挥发物提取物的引诱作用不明显;3种寄主植物和挥发物提取物分别两两之间比较时,烟粉虱的选择行为均极显著地表现为番茄 > 甘蓝 > 辣椒。2）番茄、甘蓝和辣椒具有不同的挥发物化学图谱,且挥发物组分的相对百分含量差异很大;番茄挥发物总量远远大于甘蓝和辣椒;从组分来看,番茄挥发物中主要为萜烯类（89.8%）,甘蓝挥发物中主要为烷烃类（53.0%）。3）8种寄主植物挥发物标样（10-¹～10^-6 μL/μL）中,除1,8-桉树脑始终对烟粉虱具有引诱作用外,丁子香酚、苎烯、里那醇和月桂烯则是分别在10^-4～10^-6,10^-1～10^-4,10^-1～10^-4和10^-1～10^-4μL/μL时,才具有引诱作用;α-蒎烯、顺-3-已烯-1醇则在高浓度下（10^-1和10^-2 μL/μL）对烟粉虱具有排斥作用,低浓度下对烟粉虱没有任何影响;正十二烷在任何浓度下对烟粉虱均没有任何作用。4）在辣椒上分别喷施番茄挥发物模拟样和甘蓝挥发物模拟样,均显著增加对烟粉虱的引诱作用,而在番茄上喷施辣椒挥发物模拟样则无明显增效作用。综合分析认为,挥发性物质在B型烟粉虱对不同寄主植物的选择偏好时具有重要的行为导向作用。     

不同作物田烟粉虱发生的时空动态

2008～2009年连续2年系统调查了番茄、茄子、棉花、大豆、玉米等寄主植物上烟粉虱种群发生的时间与空间动态。结果表明：不同寄主植物上的烟粉虱成虫及其伪蛹数量有显著性差异,其密度大小依次为：茄子>棉花>番茄>大豆>玉米。其中,在玉米上除了发现极少量的成虫逗留外,没有发现烟粉虱的卵及若虫。在发生的时间序列上,烟粉虱成虫及伪蛹的数量呈现为先逐渐上升后又下降的变化过程,发生高峰期集中在8月5日到8月31日,9月初以后烟粉虱数量慢慢减少。在空间分布上,表现为烟粉虱成虫喜食寄主的上部叶片。统计分析显示,寄主对烟粉虱成虫和伪蛹的数量的影响极显著,而年份对其数量的影响没有显著差异。由此得出的烟粉虱发生和达到高峰的时间,可为烟粉虱预测预报和区域性综合治理提供重要理论依据。     

寄主植物对B型烟粉虱选择行为和生物学参数的影响

通过培养皿内自由扩散观察和生物学观察,对黄瓜、茄子、辣椒、棉花和甘薯上B型烟粉虱的寄主选择性和生物学参数进行了研究.结果表明：B型烟粉虱成虫向寄主植物叶片自由扩散的初始阶段（2 h）,各寄主植物叶片上虫量的差异不大,在随后的4～48 h内黄瓜叶片上的虫量不断增加,茄子、棉花和甘薯叶片上的虫量相对稳定,而辣椒叶片上的虫量却不断下降,说明B型烟粉虱对黄瓜的选择性最强、对辣椒的选择性最弱,且饥饿和吡虫啉预处理均不影响B型烟粉虱的寄主选择性;取食不同寄主植物烟粉虱成虫的蜜露分泌量差异显著,从高到低依次为黄瓜、甘薯、棉花、茄子、辣椒;黄瓜、茄子、甘薯、棉花上烟粉虱成虫的寿命显著长于辣椒,其平均单雌产卵量(分别为224.33粒、182.33粒、191.73粒和172.60粒)也均显著高于辣椒(47.83粒);各寄主植物上烟粉虱卵的孵化率和发育历期差异均不显著;烟粉虱若虫在黄瓜、茄子、甘薯和棉花上的发育历期分别为10.60 d、11.96 d、11.11 d和13.20 d,死亡率分别为5.21%、27.78%、17.24%和37.11%,在辣椒上不能完成正常发育.     

Functional response of Picromerus bidens: effects of host plant

Abstract:  The influence of three solanaceous plants (tomato, sweet pepper and eggplant) on the functional response of the predatory bug Picromerus bidens to densities of fourth-instar larvae of the beet armyworm Spodoptera exigua was assessed. Logistic regression indicated a type II functional response on all host plants. Over all prey densities, P. bidens killed significantly fewer fourth instars of S. exigua on tomato than on sweet pepper or eggplant (1.96 ± 0.17 vs. 4.37 ± 0.19 and 3.90 ± 0.15 larvae per predator per 24 h respectively). A higher theoretical maximum predation rate was estimated on sweet pepper (11.1 prey larvae per day) and eggplant (7.4) than on tomato (5.4). The mean number of prey killed per day by P. bidens females ranged from 0.78 at a density of one prey on tomato to 8.45 at a density of 24 prey on sweet pepper. The data indicated that the estimates of handling time ( T _h) and attack rate ( a ) were highly affected by host plant. Based on asymptotic 95% confidence intervals, a lower attack coefficient was found on tomato (0.02 h⁻¹) than on sweet pepper or eggplant (0.07 and 0.11 h⁻¹ respectively). On the other hand, handling times were significantly longer on tomato (4.42 h) and eggplant (3.23 h) than on sweet pepper (2.15 h). This laboratory study suggests that plant characteristics influence the ability of P. bidens to respond to changes in prey density.