Climate warming affects crop phenology, physiology and biochemistry in agricultural ecosystems and has cascading effects on the performance and abundance of herbivorous insect pests. In this study, a field-simulated warming experiment was conducted using MSR-2420 infrared radiation lamps to assess its effects on the population size and feeding behavior of Sitobion avenae (Hemiptera: Aphididae). Additionally, the activity of the salicylic acid (SA) and jasmonic acid (JA) pathway-related enzymes and their gene expressions in wheat were recorded. Results revealed the population of S. avenae significantly increased in the warming treatment and significantly prolonged the average duration of the E-1 and E-2 waves of S. avenae. Enzymatic assays showed the activities of phenylalaninammo-nia lyase (PAL) and beta-1,3-glucanase (beta-1,3-GA), involved in the SA pathway, and polyphenol oxidase (PPO), involved in the JA pathway, decreased following exposure to elevated warming whereas the activity of lipoxygenase (LOX), involved in the JA pathway, increased. The expression of PAL, beta-1,3-GA, involved in the SA pathway, and LOX and PPO, involved in the JA pathway, were similar to the changes in enzyme activity. Results indicated that S. avenae population increase was positively correlated with its feeding behavior and fitness, and these were correlated with decreasing wheat resistance through the SA and JA signaling pathways.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

为明确气候变暖对不同纬度带麦田麦长管蚜Sitobion avenae和禾谷缢管蚜Rhopalosiphumpadi种群动态的影响,在高纬度的河北省廊坊市(39°30′N,116°36′E)和相对低纬度的河南省原阳县-(34°55′N,114°15′E)开展红外线辐射增温试验,调查廊坊市(+2.00℃)和原阳县(+1.18℃)2个试验点的增温处理小区和对照小区麦长管蚜和禾谷缢管蚜的种群动态,并计算其盛期发生比值.结果表明,增温使廊坊市试验点的麦长管蚜始见期、峰期分别提前21、7d,使原阳县试验点的麦长管蚜始见期、峰期分别提前14、14 d;而禾谷缢管蚜的始见期和峰期仅在原阳县试验点提前31d和7d.增温使廊坊市试验点的麦长管蚜盛期蚜量、峰期蚜量分别显著增加了139.21％和77.83％,禾谷缢管蚜盛期蚜量和峰期蚜量分别显著增加了157.31％和130.16％;增温使原阳县试验点的麦长管蚜盛期蚜量、峰期蚜量分别显著增加了149.62％和176.52％,禾谷缢管蚜/麦长管蚜的盛期蚜量比值显著降低了43.21％.表明增温有利于高纬度地区(廊坊市)麦长管蚜和禾谷缢管蚜种群增长,而在低纬度地区(原阳县)仅有利于麦长管蚜种群增长.

Aphidius gifuensis Ashmead is a dominant endoparasitoid of aphids, such as Myzus persicae and Sitobion avenae, and plays an important role in controlling aphids in various habitats, including tobacco plants and wheat in China. A. gifuensis has been successfully applied for the biological control of aphids, especially M. persicae, in green houses and fields in China. The corresponding parasites, as well as its mate-searching behaviors, are subjects of considerable interest. Previous A. gifuensis transcriptome studies have relied on short-read next-generation sequencing (NGS), and the vast majority of the resulting isotigs do not represent full-length cDNA. Here, we employed a combination of NGS and single-molecule real-time (SMRT) sequencing of virgin females (VFs), mated females (MFs), virgin males (VMs), and mated males (MMs) to comprehensively study the A. gifuensis transcriptome. Behavioral responses to the aphid alarm pheromone (E-β-farnesene, EBF) as well as to A. gifuensis of the opposite sex were also studied. VMs were found to be attracted by female wasps and MFs were repelled by male wasps, whereas MMs and VFs did not respond to the opposite sex. In addition, VFs, MFs, and MMs were attracted by EBF, while VMs did not respond. According to these results, we performed a personalized differential gene expression analysis of olfactory gene sets (66 odorant receptors, 25 inotropic receptors, 16 odorant-binding proteins, and 12 chemosensory proteins) in virgin and mated A. gifuensis of both sexes, and identified 13 candidate genes whose expression levels were highly consistent with behavioral test results, suggesting potential functions for these genes in pheromone perception.

Aphid saliva plays important roles in aphid-host interactions, such as assisting aphid digestion, detoxification, activating or suppressing plant defenses. The grain aphid, Sitobion avenae, is one of the most devastating pests of cereals worldwide. In this study, we performed the transcriptome analysis of salivary glands of S. avenae. A total of 33,079 assembled unigenes were identified in the salivary glands of aphids. Of the all obtained unigenes, 15,833(47.86%) and 10,829(32.73%) unigenes showed high similarity to known proteins in Nr and Swiss-Prot databases respectively. 526 unigenes were predicted to encode secretory proteins, including some digestive and detoxifying enzymes and potential effectors. The RT-PCR and RT-qPCR results showed that all of the 15 most highly expressed putative secretory proteins specifically expressed in salivary glands. Interestingly, 11 of the 15 most highly expressed putative secretory proteins were still not matched to function-known proteins. We also detected the expression of 9 interested putative secretory proteins in aphid different tissues, including some digestive and detoxifying enzymes, effectors and Ca2+ binding proteins. The results showed that only glutathione-S-transferase 1 was specifically expressed in salivary glands. These findings provide a further insight into the identification of potential effectors involving in aphid-cereals interactions.

在长期的协同进化过程中,昆虫与其体内的共生菌建立了密切的互利共生关系.昆虫内共生菌不仅能调控宿主昆虫的营养代谢和生殖代谢,还能协助昆虫抵御生物、非生物胁迫,提高昆虫对化学农药的抗性及对寄主植物的适应性等.因此,内共生菌是宿主昆虫生长发育及适应性的重要调控因子.目前,随着组学技术的不断发展,内共生菌在宿主昆虫和寄主植物中的原位功能不断被挖掘,通过对内共生菌-昆虫-植物互作模型的研究,将进一步揭示昆虫内共生菌与昆虫、植物的互作机理,加深对昆虫适应性机制的理解并推进新型害虫防控和靶标技术的研发.本文就昆虫内共生菌的起源、特点、分布和传递,昆虫内共生菌在昆虫-植物-环境互作中的作用,以及昆虫内共生菌研究的方法和新技术等方面进行了综述,并对未来昆虫内共生菌介导的防御效应及昆虫适应性机理等热点问题进行了展望.

茉莉酸（JA）与水杨酸（SA）为植物体内重要的防御反应信号物质,在植株受到机械损伤或病虫害侵害时可作为信号物质,激活下游相关防御反应.为应对植株的防御反应,昆虫通常通过提高自身相关解毒酶活性或分泌唾液蛋白调节寄主防御反应以增强对寄主植株适应性.本研究以桃蚜（Myzus persicae（Sulzer））体内的重要解毒酶谷胱甘肽-S-转移酶（GST）的sigma型及唾液腺特异表达基因C002为研究对象,分别以含有5 mmol/L JA或10 mmol/L SA的人工饲料直接饲喂桃蚜,在不同的取食时间点收集蚜虫,通过荧光定量PCR检测JA或SA对目的基因sigma GST及C002表达诱导反应.结果发现,当桃蚜直接取食含有JA或SA的人工饲料后,sigma GST及C002表达量都显著升高.表明,桃蚜可直接利用寄主植株防御反应信号物质JA或SA,提高体内相关解毒酶或者唾液蛋白基因表达量,以提高对寄主防御的适应性.为进一步开展桃蚜对植物防御反应适应性研究提供新的思路.

Odorant-binding proteins (OBPs) and chemosensory proteins (CSPs) of aphids are thought to be responsible for the initial molecular interactions during olfaction that mediate detection of chemical signals. Analysis of the diversity of proteins involved comprises critical basic research work that will facilitate the development of sustainable pest control strategies. To help us better understand differences in the olfactory system between winged and wingless grain aphids, we constructed an antennal transcriptome from winged and wingless Sitobion avenae (Fabricius), one of the most serious pests of cereal fields worldwide. Among the 133,331 unigenes in the antennal assembly, 13 OBP and 5 CSP putative transcripts were identified with 6 OBP and 3 CSP sequences representing new S. avenae annotations. We used qPCR to examine the expression profile of these genes sets across S. avenae development and in various tissues. We found 7 SaveOBPs and 1 SaveCSP were specifically or significantly elevated in antennae compared with other tissues, and that some transcripts (SaveOBP8, SaveCSP2 and SaveCSP5) were abundantly expressed in the legs of winged or wingless aphids. The expression levels of the SaveOBPs and SaveCSPs varied depending on the developmental stage. Possible physiological functions of these genes are discussed. Further molecular and functional studies of these olfactory related genes will explore their potential as novel targets for controlling S. avenae.

The full-length cDNA of functionally-unknown salivary protein C002 in Schizaphis graminum was cloned using rapid amplification of cDNA ends (RACE) and designated as SgC002 (GenBank accession no. KC977563). It is 767 bp long and encodes a protein of 190 amino acid residues with a predicted mass of 21.5 kDa and a predicted cleavage site of N-terminal signal peptide between the 24th and the 25th residues. SgC002 is specifically expressed in salivary gland with the highest level at the 2nd instar. Introducing SgC002-specific 476-siRNA, but not 546-siRNA to aphids through artificial diet significantly suppressed SgC002 expression. Silencing SgC002 gene led to lethality of the aphid on wheat plants, but not on pure artificial diet. Our study demonstrated that artificial diet-mediated RNAi can be a useful tool for research on the roles of genes in aphid salivary gland, and also provided new insights into the characteristics of C002 in wheat aphids.

[目的]测定麦长管蚜Sitobion avenae Fabricius对E-β-法尼烯(E-β-farnesene,EβF)矿物油溶液反应的最低阈值浓度,为EβF的田间应用提供依据.[方法]观察麦长管蚜3龄若蚜对不同浓度EβF的逃逸行为和“Y”型管嗅觉行为反应.每天定时分5次(9:00,11:30,14:00,16:30和19:00)滴加10 μL EβF于滤纸上,滤纸用牙签固定于麦苗盆中心,持续处理5d.每盆麦苗处理前接1龄若蚜15头.记录成蚜翅型及2周后蚜虫总数量.[结果]随着EβF浓度升高,麦长管蚜3龄若蚜3 min内逃离数显著增加,有翅蚜比例显著增加,种群个体数量显著下降,驱避效果明显增强.EβF浓度为200 ng/μL和≥600 ng/μ L使蚜虫逃离数显著增加(P＜0.05).“Y”型管选择行为测试结果表明,EβF≥600 ng/μL对3龄若蚜具有极显著的驱避作用(P＜0.01).与对照相比,EβF≥600 ng/μL处理极显著提高了有翅蚜比例(P＜0.01);EβF≥400 ng/μL极显著抑制蚜虫种群个体数量增长(P＜0.01),但与600 ng/μL处理差异不显著.[结论]600 ng/μL EβF矿物油溶液为麦长管蚜驱避剂的最低阈值浓度.

采用浸渍法测定了博落回提取物(MCE)对不同龄期麦长管蚜、禾谷缢管蚜、麦二叉蚜的生物活性.结果显示,博落回提取物对不同龄期3种麦蚜均有一定杀虫活性,对麦长管蚜、禾谷缢管蚜、麦二叉蚜4龄有翅若蚜48 h致死中浓度LC50分别为8.185 1、5.313 5、2.682 4 g/L,有翅成蚜48 h LC50分别为8.575 0、6.614 7、0.590 4 g/L,毒力大小均为:麦二叉蚜＞禾谷缢管蚜＞麦长管蚜,麦二叉蚜对博落回提取物最敏感.研究结果为进一步开展博落回对麦蚜活性组分的分离纯化奠定了基础.

[Objectives] Semiochemicals are involved in tritrophic interactions and affect the behaviors of both herbivores and beneficial insects. Many volatile molecules from the wheat plant [Triticum aestivum L.(Gramineae)] have previously been identified. To understand their effects on aphids and related auxiliaries. [Methods] The impact of four of these volatiles; methyl-salycilate, cis-3-hexenyl acetate, hexenol, and 1-hexanol, was tested on the wheat aphid [Sitobion avenae(Fabricus)(Homoptera: Aphididae)] and two major predators of this pest encountered in field crops, the hoverfly(Episyrphus balteatus(De Geer)(Diptera: Syrphidae)] and the multicoloured Asian ladybird [Harmonia axyridis(Pallas)(Coleoptera: Coccinellidae)]. Different doses of these chemicals were tested by performing four arm-olfactometer and wind-tunnel assays. [Results] The results show that methyl-salycilate seemed to be attractive only toward H. axyridis but 3-hexenyl acetate and hexenol were attractive to both S. avenae and H. axyridis. However, these positive responses decreased with increased dose of the tested compounds. 3-hexenyl acetate also induced positive response in E. balteatus but 1-hexanol was more attractive to aphids than to their natural enemies. [Conclusion] In conclusion, these results highlight the potential benefit of combining methyl-salycilate, 3-hexenyl acetate and hexenol in push and pull traps aimed to control S. avenae. Contrary to the three aforementioned compounds, 1-hexanol did not seem to have much potential as a semiochemical for the biological control of aphids.

为进一步揭示环境因子对马铃薯甲虫成虫越冬出土的影响,运用ArcGIS软件的空间分析工具,研究了越冬代成虫出土后的空间分布格局,同时比较了土壤温度、湿度对其出土规律的影响.结果显示,越冬代马铃薯甲虫成虫出土后主要聚集在刚出土的马铃薯苗上,拥挤度指标(m*/m)为1.83,呈聚集分布.2011、2012年乌鲁木齐市马铃薯甲虫出土的起点温度分别为10.6℃和13.0℃,而2011年察布查尔县起点温度为14.6℃,且逐日出土虫量与土壤温度呈线性正相关.5月降水量大的年份马铃薯甲虫出土较早.研究表明,土壤温、湿度是影响马铃薯甲虫越冬代成虫出土活动的重要因素.

近几年通过国内外科研协作,小麦及蔬菜蚜虫基础及防控技术研究有了长足进展:在害虫行为调控技术方面,通过蚜虫报警激素反-β-法尼烯[(E)-β-Farnesene,EBF]等挥发物缓释对蚜虫及其天敌种群调查,明确了田间应用剂量及持效期、释放点间距、释放器放置高度,以及EBF与化学农药协调应用对蚜虫控制及对天敌的引诱效果及其作用机理,发展了防控小麦、蔬菜蚜虫的“推-拉”技术;在利用作物多样性布局对害虫生态调控技术方面,研究明确小麦与多种作物间、套及混种对蚜虫具有良好控制作用及其最佳作物布局模式,并揭示其降低蚜虫密度、保护天敌及提高土地利用当量等增产效果;筛选了植物源杀虫活性成分,发现博落回提取物中血根碱及植物凝集素对麦蚜具有强杀虫活性,开发获得了一种博落回提取物(Macleaya cordata extract,简称MCE)与烟碱复配配方,杀蚜虫效果达98.9％;通过技术集成研究与示范,在河南、河北与山东推广应用;并采用可量化评价体系,获得当地农民及农技推广部门的反馈意见,对区域集成技术进行调整.研究结果对改变目前过度依赖化学农药防治小麦、蔬菜病虫害的现状,减少农药使用和残留、促进农民增收等小麦、蔬菜病虫害绿色防控技术的开发推广及食品安全具有重要意义.

In order to develop biological control of aphids by a “push-pull” approach, intercropping using repellent emitting plants was developed in different crop and associated plant models. Garlic is one of the potential plant that could be inserted in crops to decrease the pest occurrence in neighboring crop plots. In this study, field works were conducted in wheat fields in Langfang Experimental Station, Hebei Province in China from October 2009 to July 2010 during wheat developmental season. The effect of wheat intercropping with garlic but also the volatiles emission on the incidence of the English grain aphid, Sitobion avenae Fabricius (Homoptera: Aphididae) was assessed. Natural beneficial occurrence and global yields in two winter wheat varieties that were susceptible or resistant to cereal aphid were also determined comparing to control plots without the use of garlic plant intercrop nor semiochemical releaser in the fields. S. avenae was found to be lower in garlic oil blend treatment (GOB), diallyl disulfide treatment (DD) and wheat-garlic intercropping treatment (WGI) when compared to the control plots for both two varieties (P<0.01). Both intercropping and application of volatile chemicals emitted by garlic could improve the population densities of natural enemies of cereal aphid, including ladybeetles and mummified aphids. Ladybeetle population density in WGI, GOB and mummified aphids densities in WGI, DD were significantly higher than those in control fields for both two varieties (P<0.05). There were significant interactions between cultivars and treatments to the population densities of S. avenae. The 1 000-grain weight and yield of wheat were also increased compared to the control. Due to their potential alternatives as a biological control agent against cereal aphid, garlic intercropping and related emitted volatiles are expected to contribute to the further improvement of integrated pest management systems and to potentially reduce the amount of traditional synthetic pesticides applied in wheat fields.

In order to estimate their trapping effect on wheat aphids and their natural enemies,yellow sticky card traps were setup in wheat fields at the Luancheng agro-ecosystem station of the Chinese Academy of Science in Hebei Province in 2010 and 2011. More than 30 species of insect from 7 orders were trapped; the dominant species captured was a fly species rather than wheat aphids. The effectiveness of yellow sticky card traps for trapping wheat aphids was significantly correlated to the population size per 100 tillers when application of chemical pesticides in sampling area were under control and was not significant without such control. Yellow sticky card traps can kill a large number of natural enemies of the wheat aphid. The ratio of trapped natural enemies and pest insects before and after the grouting stage were both greater than 1,with the maximum ratio up to 45. 50. In view of the effectiveness of yellow sticky card traps in catching wheat aphids and their natural enemies and the potential influence of weather conditions and other factors,these traps are not recommended for controlling wheat aphids but can be used as a tool for monitoring these pests.

In the recent years,more and more researches were conducted on the impact of plant lectins on aphid controlling. In this paper,plant lectins' classification,anti-aphid effect and mechanism,and qualitative and quantitative detecting methods were introduced. Then,the application of monocot mannose-binding lectin and the legume lectin family in anti-aphid,and their impact on natural enemies of aphids were summarized. Finally,lectin's application perspectives and potential problems was also discussed.

为了解不同耕作方式对麦红吸浆虫Sitodiplosis mosellana (Géhin)种群动态的影响,2010年和2011年,在中国科学院河北省栾城农业生态系统试验站不同耕作方式的小麦样地中,通过淘土、成虫网捕和剥穗等方法对麦红吸浆虫进行了调查研究.结果表明:两年取土筛检出的幼虫数量依次为秸秆还田免耕田＞秸秆站立免耕田＞秸秆还田旋耕田,但2011年网捕调查显示,秸秆还田旋耕田中的成虫数量高于另外两种样地.两年剥穗检查出的幼虫数量的排序与取土筛检出的幼虫数量的排序相反,依次为秸秆还田旋耕田＞秸秆站立免耕田＞秸秆还田免耕田.分析表明免耕有利于幼虫的越冬,但免耕田麦穗受害较轻.旋耕对幼虫越冬不利,但抽穗后受害较严重.在耕种方式是旋耕的情况下,漫灌可加重吸浆虫的危害.研究结果有助于进一步了解大范围耕作方式的变迁对麦红吸浆虫发生的影响.

With the serious problems of herbivorous insect outbreaks and species extinction caused by monocultured crops in large areas,the wide and heavy use of chemical pesticides has made the destruction and instability of agroecosystems to rise.Thus,based on the relationships among biodiversity-agroecosystem-herbivorous insect,studying the impacts of conservation and application of biodiversity on pest control and developing new techniques for ecological manipulation in agroecosystems have become the highlights of research on sustainable agriculture.This paper reviewed the importance and ecological effects of biodiversity on herbivorous insects in agroecosystems,and the prospects and applications of biodiversity in agricultural cultivation was further discussed.

采用田间成株期自然感蚜法和室内苗期接虫法,鉴定12个小麦品种(系)对5个不同地区荻草谷网蚜Sitobion miscanthi (Takahashi)种群的抗性.结果表明,小麦品种(系)室内苗期的抗性表现与田间成株期基本一致；Amigo、KOK、北京837、铭贤169和红芒红对5个地理种群荻草谷网蚜的抗性表现相同,丰产3、中4无芒、JP①、晋麦31、L1、885479-2和小白冬麦对5个地理种群荻草谷网蚜种群的抗性表现则存在差异.研究表明我国荻草谷网蚜对抗蚜作物品种具有致害性分化.