ELECTROANTENNOGRAM RESPONSES OF LYSIPHLEBIA JAPONICA ASHMEAD (HYMENOPTERA: APHIDIIDAE) TO SOME COTTON PLANT VOLATILES AND COTTON APHID PHEROMONES

Abstract Electroantennogram responses (EAGs) of Lysiphlebia japonica (Ashmead) (Hymenoptera: Aphidiidae) to cotton plant volatiles and cotton aphid pheromones were measured with EAG recording techniques. No sexual difference of EAG responses was found to all test samples under concentration of 10 μl/ml. The most effective chemicals were 1-heptanol, hexanal, heptanal, saturated primary-alcohols with six-carbon to nine-carbon chain and benzaldehyde. Both male and female showed the highest EAGs to green leaf volatiles (GLVs) and moderate EAGs to terpenoids among which geraniol was the most active. Cotton aphid pheromones elicited relative high EAGs. Among the four plant extracts, cotton leaf extract was the most effective. Dose curves were constructed from six female wasps' EAGs to four chosen chemicals, in which GLVs showed lower thresholds than terpenoids. According to the results above, we may draw the following conclusions: GLVs could be more important in longer distance orientation, while terpenoids may be more important in shorter ranges. Aphid pheromones may be effective attractants to parasitoids. Preadult experience can influence the antenna1 sensitivity of the parasitoid.     

大豆蚜触角嗅觉感器结构及其功能

采用扫描电镜观察大豆蚜Aphis giycines各型触角上嗅觉感器的细微结构,结合触角电位记录,发现大豆蚜有翅孤雌生殖蚜对萜烯衍生物的感受部位在第6节原生感器上,而萜烯烃类则在第5节原生感器上,两原生感器都对绿叶气味和芳香类起嗅觉反应。末端2节上还有其它化学感器对植物气味起反应。因此,各型对植物气味的感觉部位在末端2节上。各型对报警信息素的作用部位主要在第6节原生感器上,无翅型第5节原生感器和有翅型第3节次生感器也有一定的感觉能力。     

Olfactory antennal responses to plant volatiles in apterous virginoparae of the vetch aphidMegoura viciae

Electroantennogram (EAG) responses were recorded from apterous virginoparae of the vetch aphidMegoura viciae Buckton (Homoptera, Aphididae) to more than eighty volatile compounds in order to investigate its sensory ability to perceive plant odours. The response profile ofM. viciae reveals a differential sensitivity for the array of plant volatiles tested. The whole group of general green leaf volatiles is very stimulatory. In addition to (E)-2-hexenal, the following compounds of this group elicit large EAG responses: (E)-2-heptenal, 1-octenol-3, hexyl acetate, (Z)-3-hexenyl acetate, hexanol-1, hexanal, 2-heptanone and 3-octanone. Relatively large EAGs are also produced by 4-methoxybenzaldehyde (p-anisaldehyde), hexanonitrile, heptanonitrile, 1,6-hexanedithiol, butyl isothiocyanate, 4-pentenyl isothiocyanate, (−)-(1S)-β-pinene, (+)-(S)-carvone, (−)-(R)-carvone, α-terpineol, linalool and citronellal. The nitriles are the most effective of all plant volatiles tested. Structure-activity relationships occur in various groups of chemicals and members of the green leaf volatiles, benzaldehydes, isothiocyanates and monoterpenes are ranked accordingly. In the group of green leaf volatiles, aliphatic aldehydes are more stimulating than the corresponding alcohols. EAG responses to series of saturated aliphatic alcohols and aldehydes reveal that C₆ and C₇ compounds are the most stimulatory. Dose-response curves show that the rank order of EAG response amplitudes hardly changes at lower dosages. It is concluded thatM. viciae perceives general plant volatiles as well as more-specific components, such as nitriles and isothiocyanates, associated with the odour blends of non-host plant species.     

大豆蚜嗅觉在选择寄主植物中的作用

大豆蚜ＡＰｈｉｓｇｌｙｃｉｎｅｓ有翅和无规孤雌生殖蚜为其寄主植物大豆叶和鼠李叶气味所引诱,而非奇主植物棉花叶和黄瓜叶气味处于中性,丝瓜叶和南瓜叶气味具有明显的排斥作用。非寄主植物气味可以遮蔽寄主植物气味的引诱作用。大豆蚜触角感受器对植物气味具有嗅觉生理反应,对一些化合物的最小感觉阈值达１０－５至１０－６体积比浓度,表明大豆蚜触角上存在识别植物气味的嗅觉受体细胞。由此证明,嗅觉在大豆蚜选择寄主植物过程中起重要作用。     

植物挥发性物质对蚜虫性信息素诱蚜效果的影响(英文)

本研究首先是在不同的寄主植物中利用蚜虫性信息素进行田间诱蚜实验。结果表明寄主植物影响性信息素田间诱蚜的种类和效果。在桃园 ,以蚜虫性信息素荆芥内酯和荆芥醇为性诱剂的水盆诱捕器 ,诱到 3种蚜虫的雄蚜 ,分别是桃蚜、桃粉大尾蚜和莲缢管蚜。其中 ,桃蚜占绝大多数 ,且还被性信息素的单一组分植物提取的荆芥内酯所吸引。麦田中诱到的雄蚜为麦二叉蚜。苹果园中诱到的雄蚜是绣线菊蚜和梨中华圆尾蚜 ,且性信息素诱捕器中的数目远多于对照诱捕器。据田间诱蚜实验结果推测 ,荆芥内酯和荆芥醇对桃粉大尾蚜有吸引作用 ,荆芥内酯可能是绣线菊蚜和梨中华圆尾蚜性信息素的一个组分。另外进行的田间实验表明寄主植物挥发性物质对蚜虫性信息素诱蚜效果有影响 ,当荆芥内酯诱捕器同时释放桃叶挥发物时 ,诱到的桃蚜雄蚜数量明显增加。触角电位记录实验也表明桃蚜雄蚜对桃叶挥发物和桃芽挥发物有反应。     

Comparison of the olfactory sensitivity of two sympatric steppe grasshopper species (Orthoptera: Acrididae) to plant volatile compounds

Two Oedipodinae grasshopper species Oedaleus decorus asiaticus B.-Bienko and Angaracris baraben-sis Pall. (Orthoptera: Acrididae) are important pests on the natural grasslands in Inner Mongolia and often require insecticide treatment during outbreaks[1]. They both prefer overgrazed steppes and xerophytous habi-tats, and have thus been suggested as indicator species for steppe deterioration in typical steppe zones of In-ner Mongolia[2]. The two species have a sympatric distribution and sync…     

RELEVANCE OF PLANT VOLATILES TO SEX PHERO‐MONE IN LURING APHIDS IN THE FIELD1

Abstract Outdoor trials were made to test the responses of male aphids to pheromone lures in fields with different host‐plants, in order to know whether host‐plants would affect catches of males to pheromone lures. In peach orchard, males of three aphid species, i.e. Myzus persicae, Hyalopterus amygdali and Rhopalosiphum nymphaeae, were found in traps baited with aphid sex pheromone nepetalactone and nepetalactol. The most numerous numbers was M, persicae and it was also attracted by plant‐derived nepetalactone alone in peach orchard and cabbage garden. Schizaphis graminum males were caught in water traps in wheat field. In apple orchard, males of two aphid species, Aphis cifricola and Sappaphis sinipiricola were caught in significantly larger numbers in the pheromone traps than in the control traps. Field study indicated that the sex pheromone of H. amygduli comprises either one or both of nepetalactone and nepetalactol, and nepetalactone may be one component of sex pheromones of A cifricola and S sinipiricola Another field trial had shown that catches were increased if volatiles from a steam‐distilled extract of peach leaves were released simultaneously with nepetalactone. Elec‐troantennograms (EAGs) were recorded from males of M. persicae to volatiles of peach leaves and buds.     

An improved aphid electroantennogram

Excised antennae have been used to record aphid electroantennograms (EAGs) but these preparations have small, rapidly declining responses and a short usable life. An improved EAG technique is described and evaluated using alate virginoparae of the black bean aphid, Aphis fabae, and a series of plant volatiles. EAG recording with fine-tip glass electrodes inserted into the surface of the intact antenna of a whole insect preparation gave stable EAG peaks of a few mV and EAG peak amplitude decreased by only 22% over an 8 hour recording period. The EAG responses showed typical dose-dependent characteristics. There was variation in EAGs from different preparations, so normalisation of the EAG responses against a standard stimulus is still necessary. The thirty compounds tested elicited an EAG response profile largely similar to that reported previously from excised antennae. EAG responses recorded with the electrode at three different positions, between the 5th-6th (A), 4th-5th (B), and 3rd-4th (C) antennal segments, were smaller when recorded closer to the head. Position B produced larger EAG responses than those at C although there was no olfactory receptor between position B and C.     

高温对共存种棉蚜与棉长管蚜死亡及繁殖的影响

棉蚜和棉长管蚜是棉花上的共存种,为探索其年内及年际间优势地位的不同是否与两者对高温的不同响应有关,室内研究了高温胁迫(32、34、36和38℃)对棉蚜和棉长管蚜死亡及繁殖的影响.结果表明:随着温度的升高和高温持续天数的延长,棉蚜和棉长管蚜累计死亡率均升高,棉长管蚜累计死亡率高于棉蚜;两种蚜虫的每日死亡率可用互补重对数模型较好地拟合,模型估计的棉蚜和棉长管蚜半数致死温度值随高温持续天数的延长而降低,棉蚜半数致死温度高于棉长管蚜;在32 ～ 38℃范围内,两种蚜虫的繁殖率随温度的升高而降低,棉蚜繁殖率显著高于棉长管蚜,表明在32℃以上高温条件下,棉蚜比棉长管蚜更具有竞争力.随着全球气候变暖,由于棉蚜比棉长管蚜更耐高温,推测未来棉蚜比棉长管蚜竞争优势更加明显.     

Volatiles from four Astragalus species: phenological changes and their chemotaxonomical application

This paper shows the changes of the volatile compounds from four Astragalus species at three phenological stages: leaf development, flowering and fructification, which might be connected with the plant defense. After GC/MS analyses of Astragalus glycyphyllos L., A. hamosus L., A. cicer L. and A. spruneri Boiss., different groups of volatile compounds were found: hydrocarbons, alcohols, aldehydes and ketones, esters, terpenes, chlorinated compounds, etc. Identified volatiles were used for a cluster analysis in order to make chemotaxonomic conclusions for these evolutionary different species.     

Differential metabolisms of green leaf volatiles in injured and intact parts of a wounded leaf meet distinct ecophysiological requirements

Almost all terrestrial plants produce green leaf volatiles (GLVs), consisting of six-carbon (C6) aldehydes, alcohols and their esters, after mechanical wounding. C6 aldehydes deter enemies, but C6 alcohols and esters are rather inert. In this study, we address why the ability to produce various GLVs in wounded plant tissues has been conserved in the plant kingdom. The major product in completely disrupted Arabidopsis leaf tissues was (Z)-3-hexenal, while (Z)-3-hexenol and (Z)-3-hexenyl acetate were the main products formed in the intact parts of partially wounded leaves. (13)C-labeled C6 aldehydes placed on the disrupted part of a wounded leaf diffused into neighboring intact tissues and were reduced to C6 alcohols. The reduction of the aldehydes to alcohols was catalyzed by an NADPH-dependent reductase. When NADPH was supplemented to disrupted tissues, C6 aldehydes were reduced to C6 alcohols, indicating that C6 aldehydes accumulated because of insufficient NADPH. When the leaves were exposed to higher doses of C6 aldehydes, however, a substantial fraction of C6 aldehydes persisted in the leaves and damaged them, indicating potential toxicity of C6 aldehydes to the leaf cells. Thus, the production of C6 aldehydes and their differential metabolisms in wounded leaves has dual benefits. In disrupted tissues, C6 aldehydes and their α,β-unsaturated aldehyde derivatives accumulate to deter invaders. In intact cells, the aldehydes are reduced to minimize self-toxicity and allow healthy cells to survive. The metabolism of GLVs is thus efficiently designed to meet ecophysiological requirements of the microenvironments within a wounded leaf.     

Electroantennogram responses of the carrot fly, Psila rosae, to volatile plant components

ABSTRACT. Electroantennogram (EAG) responses of male and female carrot flies, Psila rosae F. (Diptera: Psilidae), were recorded to thirty-six volatile plant constituents. The most distinct EAG responses were obtained to: (1) the general green leaf volatiles 1-hexanol, trans-2-hexen-1-ol and cis-3-hexen-1-ol, their isomers cis-2-hexen-1-ol and trans-3-hexen-1-ol, the alcohol 1-heptanol, the ester cis-3-hexenyl acetate and the leaf aldehydes hexanal and trans-2-hexenal, and (2) from four compounds associated with the umbelliferous host plants of this insect, namely trans-methyl-iso-eugenol, β-caryophyllene, linalool and trans-2-nonenal. Higher responses were elicited by the leaf aldehydes than by the corresponding alcohols. Although the absolute amplitude of the female response was over twice that of the male, there were no differences between the relative responses to the compounds tested in both sexes, with the exception of a much higher response to the leaf aldehydes in the male. The shape of the EAG evoked by the various compounds was consistently different, with the slowest recovery being recorded for trans-methyl-iso-eugenol. While the antennal olfactory receptors of the carrot fly are sensitive to the closely related general green leaf volatiles, they are most specifically tuned to the aldehyde component of this green odour complex. In addition, the ability of this insect to discriminate between different plants may be augmented by the perception of a group of more host specific volatiles. The conformity of the responses of males and females to the compounds tested may indicate that host plant volatiles plays an additional role as an aggregation cue for both sexes.     

Comparison of the olfactory sensitivity of two sympatric steppe grasshopper species (Orthoptera: Acrididae) to plant volatile compounds

Electroantennogram (EAG) responses of male and female Oedipodinae grasshoppers, Oedaleus decorus asiaticus B.-Bienko and Angaracris barabensis Pall to 37 plant volatile compounds were recorded. The two species have sympatric distribution and synchronous seasonal activity in Inner Mongolia Grasslands. They have different host plant preference with Oedaleus decorus asiaticus graminivorous and A. barabensis forbivorous. The EAG response profiles to 37 compounds of the two species and their both sexes were similar. Most of the green leaf volatiles elicited higher EAG responses in both species and sexes than terpenic compounds and some aromatic compounds. Strong EAG responses were elicited by 6-carbon alcohols (1-hexanol, Z-hexen-2-ol-1, E-2-hexen-1-ol, E-hexen-3-ol-1), aldehyde (E-2-hexen-1-al), ester (Z-hexen-3-yl acetate), and 7-carbon alcohols (1-heptanol) in both species and sexes. Monoterpenes with functional groups of alcohols and aldehydes were more stimulating than other monoterpenes tested. The sesquiterpenes tested elicited relatively low responses. Benzaldehyde elicited the highest responses for both species among aromatic components. Oedaleus decorus asiaticus showed higher EAG responses than A. barabensis to the green leaf volatiles, 1-decanol, 1-nonanol, 1-pentanol, hexanal, Z-hexen-3-yl acetate and to the sesquiterpenes (-)-trans-caryophyllene. Males have higher responses than females in Oedaleus decorus asiaticus. No sexual difference was observed in A. barabensis. Dose-dependent responses to six selected chemicals were observed from females. In both species, all the chemicals tested elicit EAG responses at concentration between 10^-3 mol/L and 10^-2 mol/L, except that the responses of A. barabensis to terpineol had a threshold concentration of 10-2 mol/L benzaldehyde and 1-hexanol had the highest slopes in dose curves, while 1-octen-3-ol showed the smallest slope in responses to the six chemicals tested. Comparative studies on the responses of two antennal sections and the whole antenna to six selected chemicals were carried out using females of both species. A significant EAG response was only recorded from the distal part of the antenna and not from the proximal seven segments.     

麦长管蚜和禾谷缢管蚜对小麦植株挥发物及蚜害诱导挥发物的行为反应

用四臂嗅觉计测定了麦长管蚜Macrosiphum avenae和禾谷缢管蚜Rhopalosiphum padi对小麦植株挥发物及麦蚜取食诱导挥发物的行为反应,揭示了2种麦蚜的嗅觉及小麦植株的诱导防御反应特点.在所选的13种小麦植株挥发物及蚜害诱导挥发物组分中,6-甲基-5-庚烯-2-酮、6-甲基-5-庚烯-2-醇和水杨酸甲酯对这2种蚜虫表现出强的驱拒作用;反-2-己烯醛对麦长管蚜的有翅和无翅蚜的吸引作用最强;反-2-己烯醇对禾谷缢管蚜的无翅蚜吸引作用最强,反-3-己酰醋酸酯对禾谷缢管蚜有翅蚜的吸引作用最强.说明麦蚜取食能诱导小麦植株的防御反应,麦长管蚜和禾谷缢管蚜及其不同蚜型间嗅觉反应的特点不同.     

Emission of herbivore-induced volatiles in absence of a herbivore--response of Zea mays to green leaf volatiles and terpenoids

Green leaf volatiles (GLV), a series of saturated and monounsaturated six-carbon aldehydes, alcohols, and esters are emitted by plants upon mechanical damage. Evidence is increasing that intact plants respond to GLV by activating their own defense mechanisms, thus suggesting that they function in plant-plant communication. The present paper demonstrates that exposure of maize plants to naturally occurring GLV, including (Z)-3-, (E)-2- and saturated derivatives, induce the emission of volatile blends typically associated with herbivory. Position or configuration of a double bond, but not the functional group of the GLV influenced the strength of the emissions. (Z)-3-Configured compounds elicited stronger responses than (E)-2- and saturated derivatives. The response to (Z)-3-hexen-1-ol increased linearly with the dose between 200 and 1000 nmol per plant. Not only the naturally occurring (E)-2-hexenal, but also (E)-2-pentenal and (E)-2-heptenal induced maize plants, although to a lesser extent. Externally applied terpenoids [(3E)-4,8-dimethyl-1,3,7-nonatriene, beta-caryophyllene, and (E)-beta-farnesene] did not significantly increase the total amount of inducible volatiles in maize. Of three tested maize cultivars Delprim and Pactol responded much stronger than Attribut. Recovery experiments in the presence and absence of maize plants demonstrated that large proportions of externally applied GLV were assimilated by the plants, whereas (3E)-4,8-dimethyl-1,3,7-nonatriene was recovered in much higher amounts. The results furthermore suggested that plants converted a part of the assimilated leaf aldehydes and alcohols to the respective acetates. We propose that GLV not only can alert neighboring plants, but may facilitate intra-plant information transfer and can help mediate the systemic defense response in a plant.     

槐绿虎天牛对柠条锦鸡儿6种挥发物的EAG和行为反应

【目的】为了研究槐绿虎天牛Chlorophorus diadema(Motschulsky)对主要寄主植物柠条锦鸡儿Caragana kroshinskii(Kom.)挥发物中醇类、醛类、烷类、酯类和萜烯类共5类6种化合物的生物活性。【方法】采用EAG和嗅觉行为生测技术,测定槐绿虎天牛雌雄虫对1-癸醇、正壬醛、正十六烷、乙酸-2-乙基丁酯、1-十六烯和1-辛烯6种化合物单一组分8个浓度梯度及其20种组合配方的电生理和嗅觉行为反应。【结果】结果表明,槐绿虎天牛雌雄虫对单一化合物和组合配方的EAG反应值与嗅觉行为反应选择率的变化趋势基本一致。组合配方中,雌雄虫均对S、P、Q、H、I和B 6种配方的引诱活性与对照的差异性具有统计意义(P<0.05)。【结论】(1)组合配方明显较单一组分配方对槐绿虎天牛的引诱效果好;(2)由1-癸醇、正十六烷和正壬醛组成的S配方引诱效果最好;(3)1-癸醇、正十六烷、正壬醛和1-十六烯4种化合物的最适浓度可以作为槐绿虎天牛植物源引诱剂的成分作进一步的研究。     

黑蝗对植物气味及其挥发性化合物的嗅觉反应(英文)

本文使用触角电位技术研究了黑蝗雄虫的嗅觉反应,测试的材料包括5种植物叶片、9种植物挥发性气味化合物及它们的定量混合物。在5种植物材料中,路易斯安纳蒿和紫花苜蓿能引起更大的电位反应,而3种禾本科植物的反应相对较小。在绿色气味化合物中,6-碳醇类如E-2-hexen-l-ol和E-3-hexen-l-ol导致最高的电位反应,而pentenol、3-pentanone与空白对照间并无明显差异。在3种或4种挥发性化合物的混合物中,没有含pentenol的组合总是引起较高的电位。因此,该项研究证明pentenol和3-pentanone在这种多食性黑蝗的嗅觉定位中所起的作用不明显。另外,结合触角电位的数据资料,作者讨论了寄主植物挥发性化合物在该种蝗虫定位和选择寄主植物方面的作用。     

大豆蚜嗅觉在选择寄主植物中的作用

大豆蚜 Aphis hlycines 有翅和无翅孤雌生殖蚜为其寄主植物大豆叶和鼠李叶气味所引诱,而非寄主植物棉花叶和黄瓜叶气味处于中性,丝瓜叶和南瓜叶气味具有明显的排斥作用。非寄主植物气味可以遮蔽寄主植物气味的引诱作用。大豆蚜触角感受器对植物气味具有嗅觉生理反应,对一些化合物的最小感觉阈值达10-5至10-6体积比浓度,表明大豆蚜触角上存在识别植物气味的嗅觉受体细胞。由此证明,嗅觉在大豆蚜选择寄主植物过程中起重要作用。     

龟纹瓢虫在棉株上对棉蚜的搜索与捕食行为

研究了龟纹瓢虫在棉花上对不同密度、不同空间分布、不同来源棉蚜的搜索与捕食行为.结果表明,龟纹瓢虫对棉蚜的搜索活动随棉蚜密度增加而下降;当棉花上有充足的棉蚜时,瓢虫主要搜索和捕食棉花上部的棉蚜,很少捕食棉花中部的棉蚜,极少捕食下部的棉蚜;瓢虫对棉花不同部位上分布的2种不同来源的棉蚜捕食量没有差异;但当棉花上部主要为美9101棉花棉蚜时,瓢虫的搜索活动明显下降.龟纹瓢虫的捕食行为与蚜虫密度和空间分布密切相关.     

多异瓢虫对瓜蚜为害后植物挥发物的行为反应及挥发物成分分析

为明确寄主植物挥发物在多异瓢虫Hippodamia variegata (Goeze)搜索猎物过程中的作用, 采用Y型嗅觉仪测定了多异瓢虫成虫对来自瓜蚜Aphis gossypii Glover、 健康植株、 有蚜植株及蚜害植株本身的挥发物的行为反应。结果表明： 高密度蚜虫（≥700头/L）、 有蚜植株以及密度≥400头/盆的蚜虫为害诱导的黄瓜挥发物和密度≥200头/盆的蚜虫为害诱导的搅瓜挥发物对多异瓢虫成虫具有明显的引诱作用, 而低密度蚜虫（≤500头/L）和健康植株挥发物没有引诱作用。应用动态顶空收集法提取健康植株、 有蚜植株及蚜害植株的挥发物, 进行气质联用仪分析鉴定。结果表明, 从黄瓜健康植株、 蚜害植株和有蚜植株中分别鉴定出8, 12和18种挥发物, 主要组分为十八烯、 E-5-二十碳烯、 正十六烷和正十七烷, 诱导出的新组分为对二甲苯、 邻二甲苯、 正十三烷、 α-法呢烯、 雪松醇、 正十八烷、 正二十六烷及7种未知种类; 从搅瓜健康植株、 蚜害植株和有蚜植株分别鉴定出11, 18和20种挥发物, 主要组分为石竹烯、 十八烯、 正十六烷和正十七烷, 诱导出的新组分为苯乙烷、 对二甲苯、 间二甲苯、 α-蒎烯、 正十四烷、 长叶烯、 α-石竹烯及2种未知种类。上述结果为进一步研究挥发物中引诱多异瓢虫的有效组分奠定了必要的基础。