桑天牛卵啮小蜂雌蜂对茉莉酸诱导的桑枝挥发物的触角电位和嗅觉反应

【目的】明确桑天牛卵啮小蜂Aprostocetus prolixus雌蜂对茉莉酸诱导的桑Morus alba枝挥发物的触角电位和嗅觉反应,有利于揭示茉莉酸诱导桑枝产生间接抗性的化学机制。【方法】采用动态顶空气体法收集茉莉酸处理后的桑枝挥发物,分别通过气相色谱-触角电位联用仪(GC-EAD)和气相色谱/质谱联用仪(GC/MS)筛选和鉴定对桑天牛卵啮小蜂雌蜂有EAD活性的化合物,并比较这些活性组分的释放速率在茉莉酸处理桑枝与蒸馏水处理的对照桑枝间的差异,最后利用Y-型嗅觉测定仪明确对该寄生蜂有引诱活性的组分。【结果】桑枝经茉莉酸处理后,其挥发物中的Z-3-己烯醇、γ-萜品烯、β-水芹烯、紫苏烯、水杨酸甲酯及3种未知化合物使桑天牛卵啮小蜂雌蜂产生明显的EAD反应,并且β-水芹烯、紫苏烯和水杨酸甲酯的释放量明显高于对照,其中β-水芹烯和紫苏烯仅存在于茉莉酸处理后桑枝的挥发物中,而Z-3-己烯醇的释放速率与对照无显著差异。0.1%β-水芹烯、0.1%紫苏烯以及0.01%和0.001%水杨酸甲酯对该蜂雌蜂具有显著的引诱作用。【结论】结果提示,茉莉酸促进桑枝大量释放β-水芹烯、紫苏烯和水杨酸甲酯,是茉莉酸诱导桑树对桑天牛产生间接抗性的重要机制。     

桑天牛卵长尾啮小蜂的寄主选择定位行为

本文对桑天牛卵长尾啮小蜂Aprostocetus prolixus LaSalle et Huang的寄主选择定位行为进行了系统研究。已有研究表明,寄主植物-寄主昆虫复合体释放的挥发物对寄生蜂有显著的引诱作用。为了查明寄主植物 寄主昆虫复合体中挥发性引诱物质的来源,对不同处理桑枝（正常桑枝、机械损伤桑枝、系统枝、桑天牛Apriona germari（Hope）咬食和产卵桑枝）、桑天牛虫粪及雌雄两性桑天牛所释放的挥发物分别进行了测定。结果显示：不同处理桑枝对寄生蜂都具有显著的引诱作用,而且产卵桑枝的引诱活性最大;桑天牛虫粪的气味对寄生蜂有引诱活性,而雌、雄桑天牛体表挥发物对寄生蜂的引诱效果不明显。桑天牛爬行痕迹对寄生蜂的微栖境接受行为没有影响,而桑天牛虫粪中的信息物质在寄生蜂的微栖境接受过程中起着重要作用。寄生蜂对产卵桑枝段的选择几率明显高于正常桑枝段和咬食桑枝段,而对不同植物上产卵刻槽的选择没有差异; 刻槽表面存在着与此卵寄生蜂寄主识别相关的信息物质。     

取食不同寄主植物桑天牛的虫粪挥发物对桑天牛卵啮小蜂的引诱活性及其组分分析

为了深入理解桑天牛Apriona germari虫粪挥发物在桑天牛卵啮小蜂Aprostocetus prolixus寄主定位中的作用, 本研究通过嗅觉生测比较分析了取食不同寄主植物（桑树Morus alba、 柘树Cudrania tricuspidata和构树Broussonetia papyrifera）的雌雄两性桑天牛成虫的虫粪挥发物对桑天牛卵啮小蜂的引诱活性, 并利用热脱附-气相色谱-质谱联用仪（TCT-GC-MS）对不同桑天牛虫粪挥发物的组分进行了分析鉴定。结果表明: 取食不同寄主植物的雌性或雄性桑天牛虫粪挥发物对该寄生蜂均具有显著的引诱作用, 而不同处理间的桑天牛虫粪挥发物对该寄生蜂的引诱活性无显著差异, 这说明寄主植物的种类和桑天牛性别对于桑天牛虫粪引诱该寄生蜂的活性并无显著影响。桑天牛虫粪挥发物主要包括炔类、 酮类、醛类、酯类和萜类等化合物; 取食柘树和构树的桑天牛虫粪挥发物组分相同, 但取食桑树桑天牛的虫粪挥发物组分明显多于取食柘树和构树桑天牛的虫粪。取食同一寄主植物的两性桑天牛的虫粪挥发物的组分及其含量大致相同, 表明寄主植物对桑天牛虫粪挥发物的组分有重要影响, 而桑天牛性别对其虫粪挥发物组分无显著影响。     

桑天牛长尾啮小蜂的寄主搜索行为

桑天牛长尾啮小蜂(Aprostocetus.fkutai Miwa etSonan)对桑枝条的气味反应敏感,受桑天牛危害的桑枝条比未受害的桑枝条对长尾啮小蜂有更强烈的引诱作用;刻槽的形状对长尾啮小蜂对寄主卵的搜索行为也有一定的引诱作用,而卵对长尾啮小蜂的引诱作用不明显.     

外源茉莉酸诱导菜豆对西花蓟马和南方小花蝽的行为反应

【目的】为明确茉莉酸诱导的菜豆对西花蓟马Frankliniella occidentalis和南方小花蝽Orius similis的行为反应。【方法】采用四臂嗅觉仪测定了西花蓟马和南方小花蝽对不同浓度茉莉酸诱导菜豆后的行为反应,并用气相色谱-质谱联用仪测定了不同浓度茉莉酸处理后菜豆挥发物的成分。【结果】不同浓度茉莉酸处理的菜豆植株对西花蓟马和南方小花蝽分别有不同程度的驱避和吸引作用,以1 mmol/L的茉莉酸处理植株对西花蓟马的驱避作用最强,0.1 mmol/L的茉莉酸处理植株对南方小花蝽的吸引作用最强。不同处理菜豆的挥发物在含量和成分上存在显著差异,(Z)-3-己烯丙酸酯、2-异丙基-甲氧基毗嗦只有在茉莉酸处理植株中检测到。结合不同浓度茉莉酸处理植株对西花蓟马和南方小花蝽的行为反应及菜豆挥发物含量的变化趋势,推测(E)-2-己烯醛对西花蓟马有驱避作用,(E)-2-乙酸叶醇酯对南方小花蝽具有引诱作用。【结论】茉莉酸处理菜豆后,植物挥发物种类和含量发生了变化,在增强菜豆植株抗虫性的同时,还可增强捕食性天敌南方小花蝽的搜索和捕食能力。     

不同危害状态下寄主山核桃挥发物成分的比较及桑天牛对其组分的GC-EAD和行为反应

【目的】挖掘能影响桑天牛Apriona germari行为反应的山核桃Juglans mandshurica挥发物,为筛选桑天牛的植物源引诱剂或驱避剂提供理论依据。【方法】采用动态顶空套袋法收集不同危害状态[健康(CK)以及桑天牛取食、产卵和钻蛀危害]下山核桃释放的挥发物,并利用气相色谱-质谱联用仪(GC-MS)、气相色谱-触角电位测量系统(GC-EAD)及Y型嗅觉仪分析鉴定出桑天牛成虫对其产生电生理及行为反应的挥发物。【结果】不同危害状态下山核桃释放的挥发物皆以萜烯类和芳香族化合物居多,且有多种成分相对含量存在显著性差异,其中每种危害状态下山核桃释放的挥发物都有一种或几种特有的成分。桑天牛成虫仅对不同危害状态下山核桃释放的蒎烯、乙酸叶醇酯、壬醛、α-萜品醇、丙烯酸-2-乙基己酯及正十六烷6种挥发物产生显著的电生理反应,对其他挥发物无反应,其中雌成虫对壬醛的电生理反应最强,而雄成虫对乙酸叶醇酯的电生理反应最强。嗅觉反应结果显示,丙烯酸-2-乙基己酯仅对桑天牛雌成虫有显著的引诱作用(P0.05),而乙酸叶醇酯则仅对雄成虫有极显著的引诱作用(P0.01);壬醛对桑天牛雌雄成虫均有显著的引诱作用(P0.05),而α-萜品醇则对其有显著的驱避作用(P0.05)。【结论】本研究结果表明,乙酸叶醇酯、壬醛和丙烯酸-2-乙基己酯对桑天牛成虫有较强的引诱作用,而α-萜品醇则对其有较好的驱避作用。     

水稻挥发物对稻虱缨小蜂的引诱效果研究

【目的】通过室内测定稻虱缨小蜂Anagrus nilaparvatae对水稻单一挥发物和混合挥发物的行为反应,研究水稻挥发物对稻虱缨小蜂的引诱效果,为进一步探索信息化合物在害虫防治中的应用提供理论依据。【方法】利用Y型嗅觉仪测定醇类、酮类、酚类、醛类、烯类和吲哚类等12种水稻单一挥发物对稻虱缨小蜂的引诱效果,利用引诱效果显著的单一化合物进行特定浓度的混配,进而测定稻虱缨小蜂对混合水稻挥发物的行为反应。【结果】单一挥发物中,香叶基丙酮(0.1 mg/L)、2-庚醇(1 mg/L)、正壬醇(10 mg/L)和β-石竹烯(0.01 mg/L)对稻虱缨小蜂有显著的引诱效果;对具有引诱效果的单一挥发物进行混配发现,No.1,No.3,No.4和No.10这4种组合的混合物对稻虱缨小蜂的行为有显著的影响。【结论】水稻挥发物能够影响稻虱缨小蜂的行为反应,但其引诱效果受挥发物种类、浓度和混配比例等多种因素的影响。     

外源茉莉酸诱导植物反应对菜蛾绒茧蜂寄生选择行为的影响

茉莉酸是植物体内重要的伤信号分子,向植物施用外源茉莉酸后, 可诱导植物产生各种防卫反应, 如挥发物组成发生改变等, 进而影响植食性昆虫及其天敌。该文报道用不同浓度外源茉莉酸处理白菜和甘蓝后,诱导植物反应所产生的挥发物对菜蛾绒茧蜂搜索及寄生选择行为的影响。外源茉莉酸处理白菜和甘蓝后,处理植株的挥发物对菜蛾绒茧蜂的引诱力增强;与在对照植株上相比,该蜂对经茉莉酸处理后白菜植株上的小菜蛾幼虫的寄生数显著要高。表明茉莉酸处理白菜及甘蓝后,植物诱导反应导致其挥发物的作用发生变化,进而可提高该蜂的搜索和寄生效率。     

信息化合物在平腹小蜂寄主选择过程中的作用

利用“Y”型嗅觉仪研究了平腹小蜂对不同荔枝品种的离体叶片、活体植株、叶片挥发油和挥发物单个组分以及对荔枝蝽不同处理的的选择行为反应.结果表明,三月红和淮枝品种对平腹小蜂的引诱效果较好,而糯米糍、桂味、妃子笑和黑叶品种的作用不明显.作为荔枝叶片的主要挥发物组分,α-蛇麻烯和β-子丁香烯对平腹小蜂的引诱效果也不明显,但两者在天敌搜索寄主过程中表现为协同作用,并且当均以0.3 μl·μl^-1的浓度混合后,引诱效果最好.双向选择试验表明,平腹小蜂对荔枝蝽卵没有明显的趋性,而对荔枝蝽雌成虫及成虫腹末的水提液趋性较强.培养皿生测试验则表明,平腹小蜂在荔枝蝽卵样点处作出选择行为的数量和滞留次数最多,对荔枝蝽卵有较高的选择性.荔枝蝽成虫挥发物的主要组分(E)-2-己烯醛对平腹小蜂没有显著的引诱作用.     

蝇蛹俑小蜂对寄主及果实的趋性反应

【背景】蝇蛹俑小蜂是实蝇类害虫蛹期重要的寄生蜂之一。有关植物果实和寄主挥发物在蝇蛹俑小蜂寻找寄主过程中的作用尚不明确。【方法】采用"Y"型嗅觉仪测试了寄主和果实(健康果实和虫害诱导果实)对蝇蛹俑小蜂的引诱作用。【结果】虫伤1 d的番石榴和杨桃果实对蝇蛹佣小蜂雌蜂具有显著的引诱作用;寄主蛹——3日龄橘小实蝇蛹和4日龄瓜实蝇蛹对蝇蛹俑小蜂雌蜂也具有显著的引诱作用。蝇蛹俑小蜂雌蜂对雄蜂有显著的吸引作用。橘小实蝇性诱剂甲基丁香酚对蝇蛹俑小蜂的搜索行为则无显著影响。【结论与意义】寄主蛹和幼虫危害1 d的果实能释放对蝇蛹俑小蜂有引诱作用的物质,这可为利用蝇蛹俑小蜂防治实蝇类害虫提供基础信息。     

Different headspace profiles in wild crucifer species in response to Plutella xylostella herbivory and exogenous jasmonic acid application

Abstract  Although exogenous treatment of plants with jasmonic acid (JA) may result in induced responses similar to plant defences induced by herbivory, few studies have compared the details of insect herbivory and JA-mimicked responses. We compared volatiles of two crucifer species, Cardamine impatiens and Lepidium virginicum , in response to Plutella xylostella larval feeding and exogenous application of JA, over the entire period of time when induced changes were detectable. Significant differences in the composition and timing of volatiles occurred between herbivory and JA treatments in both plants. The quantity of nitrile and isothiocyanate released in response to herbivory was significantly larger than that upon JA treatment. In each of the two plant species, most volatile components were emitted immediately upon larval feeding and their quantity dropped rapidly once feeding ceased. In contrast, the emission of volatiles in response to JA treatment lasted for a longer period of time, and the maximum emission rate was recorded 2 and 3 days after JA treatment in L. virginicum and C. impatiens respectively. These findings are discussed in the context of signal-transduction pathways and mechanisms involved in induced emissions of plant volatiles, as well as induced defences mediated by plant volatiles.     

茶树诱导抗虫性的研究进展

为了抵御植食性昆虫的为害,植物在进化过程中形成了包括组成抗性和诱导抗性在内的复杂防御体系.在通过受体识别茶树害虫为害后,茶树会启动早期信号事件,继而激活茉莉酸、水杨酸、乙烯和赤霉素等植物激素信号通路,从而引起次生代谢物的积累,最终对害虫产生直接和间接抗性.基于近年来茶树害虫为害诱导的茶树防御反应及其相关调控机理的研究进...     

Induction of systemic acquired resistance in Zea mays also enhances the plant’s attractiveness to parasitoids

Plants under attack by caterpillars emit volatile compounds that attract the herbivore’s natural enemies. In maize, the caterpillar-induced production of volatiles involves the phytohormone jasmonic acid (JA). In contrast, pathogen attack usually up-regulates the salicylic acid (SA)-pathway and results in systemic acquired resistance (SAR) against plant diseases. Activation of the SA-pathway has often been found to repress JA-dependent direct defenses, but little is known about the effects of SAR induction on indirect defenses such as volatile emission and parasitoid attraction. We examined if induction of SAR in maize, by chemical elicitation with the SA-mimic benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH), attenuates the emission of volatiles induced by Spodoptera littoralis or exogenously applied JA. In addition, we determined how these treatments affected the attractiveness of the plants to the parasitoid Microplitis rufiventris in a six-arm-olfactometer. BTH treatment alone resulted in significant systemic resistance of maize seedlings against the pathogen Setosphaeria turcica, but had no detectable effect on volatile emissions. Induction of SAR significantly reduced the emission rates of two compounds (indole and (E)-β-caryophyllene) in JA-treated plants, whereas no such negative cross-talk was found in caterpillar-damaged plants. Surprisingly, however, BTH treatment prior to caterpillar-feeding made the plants far more attractive to the parasitoid than plants that were only damaged by the herbivore. Control experiments showed that this response was due to plant-mediated effects rather than attractiveness of BTH itself. We conclude that in the studied system, plant protection by SAR activation is compatible with and can even enhance indirect defense against herbivores.     

Involvement of jasmonate- and salicylate-related signaling pathways for the production of specific herbivore-induced volatiles in plants

We compared volatiles from lima bean leaves (Phaseolus lunatus) infested by either beet armyworm (Spodoptera exigua), common armyworm [Mythimna (Pseudaletia) separata], or two-spotted spider mite (Tetranychus urticae). We also analyzed volatiles from the leaves treated with jasmonic acid (JA) and/or methyl salicylate (MeSA). The volatiles induced by aqueous JA treatment were qualitatively and quantitatively similar to those induced by S. exigua or M. separata damage. Furthermore, both S. exigua and aqueous JA treatment induced the expression of the same basic PR genes. In contrast, gaseous MeSA treatment, and aqueous JA treatment followed by gaseous MeSA treatment, induced volatiles that was qualitatively and quantitatively more similar to the T. urticae-induced volatiles than those induced by aqueous JA treatment. In addition, T. urticae damage resulted in the expression of the acidic and basic PR genes that were induced by gaseous MeSA treatment and by aqueous JA treatment, respectively. Based on these data, we suggest that in lima bean leaves, the JA-related signaling pathway is involved in the production of caterpillar-induced volatiles, while both the SA-related signaling pathway and the JA-related signaling pathway are involved in the production of T. urticae-induced volatiles.     

Reduction of ethylene emission from Scots pine elicited by insect egg secretion

Pinus sylvestris L. is known to activate indirect defence in response to attack by an herbivorous sawfly. Egg deposition by the sawfly Diprion pini L. induces pine to release, three days after egg laying, locally and systemically terpenoid volatiles that attract parasitoids to kill the eggs. The elicitor of the pine's response is located in the sawfly's oviduct secretion enveloping the eggs after deposition. Application of this secretion on twigs with artificially conducted ovipositional woundings mimics the effects of egg deposition. Furthermore, jasmonic acid (JA) induces a volatile pattern similar, but not identical, to the one induced by egg deposition. To gain deeper insight into the transduction of plant signals induced by herbivore egg deposition, it was investigated whether ethylene emission from pine is affected by sawfly egg deposition. Systemically induced ethylene emission from differently treated pine twigs was monitored for a period of 3 d after treatment. Ethylene emissions from untreated control twigs were compared with those from twigs treated as follows: (i) sawfly egg secretion [=oviduct secretion (OVI)] was transferred on artificially wounded pine needles (attractive volatiles), (ii) needles were artificially wounded (non-attractive volatiles), and (iii) the twig was supplied with JA (attractive volatiles). Ethylene emission from systemically OVI-induced twigs was significantly lower than from untreated controls, whereas artificial wounding had no detectable effect. JA-treated twigs released much more ethylene and showed higher variability of ethylene emission than artificially wounded twigs and OVI-treated ones. Ethylene emissions from pine after the various treatments studied here are discussed with respect to known effects of insect feeding on ethylene release from plants.     

罗格列酮对海马神经元树突发育的影响

罗格列酮(rosiglitazone,Rosig.)是噻唑烷二酮类(thiazolidinediones,TZDs)过氧化物酶体增殖物激活受体γ(peroxisome proliferator-activated receptor gamma,PPARγ)的激动剂,近年来,临床研究发现其具有神经保护作用,但对其作用机制目前仍没有完全研究清楚．利用活细胞成像的方法,观察罗格列酮对大鼠海马神经元树突丝和树突树发育的影响及其机制．结果显示,罗格列酮浓度依赖的增高神经元树突丝密度,对树突丝长度、运动速度并没有影响．此外,罗格列酮也不影响树突树的总分支、总长度以及各级分支的数目和长度．PPARγ 特异性拮抗剂GW9662完全阻断了罗格列酮介导的树突丝密度增高．结果表明罗格列酮可能通过PPARγ途径影响神经元的早期发育,这可能是罗格列酮发挥神经保护作用的潜在机制．     

The effect of jasmonic acid on the accumulation of ABA,proline and spermidine and its influence on membrane injury under water deficit in two barley genotypes

Seedlings of two barley genotypes (‘Maresi’ and wild form of Hordeum spontaneum) were treated with jasmonic acid (JA 5 μM and 15 μM) for 24 h, and then subjected to water stress (PEG 6000 solution of − 1.5 MPa). JA caused an increase in the content of ABA but not in that of proline and spermidine in the two studied genotypes. The effect of the treatment did not depend on the applied JA concentration. The pre-stress treatment with JA changed plant response to water deficit with regard to membrane injury. Treatment with a lower JA concentration (5 μM) caused a substantial reduction of the stress-induced membrane damage in the both genotypes. A higher JA concentration (15 μM) caused the reduction of membrane injury only in H. spontaneum and was ineffective in ‘Maresi’. JA had no influence on the leaf water status in water-stressed plants. A possible role of JA in leaf ABA accumulation and alleviation of cell membrane injury under water deficit is discussed. The work was partly supported by the Polish Committee For Scientific Research, grant No 5 PO6A 036 18     

MeJA处理和蚧虫危害对枣树挥发物的影响

枣树(Ziziphus jujube Mill)是中国北方的一种重要经济林木。日本龟蜡蚧(Ceroplastes japonicus Green)是枣园的一种破坏性天敌。研究了外源茉莉酸甲酯(MeJA)处理和日本龟蜡蚧雌成虫危害后与对照健康枣树相比挥发物的变化。枣树挥发物的收集采用顶空收集法,并使用气相色谱/质谱联用仪(GC/MS)来分析收集到的挥发物的化学成分。结果显示:MeJA处理的和蚧虫危害的枣树挥发物的化学组分在种类和含量上与对照相比都有所改变。其中MeJA处理的枣树样本中检测到22种挥发物,总挥发量为37347 ng/h;蚧虫危害的枣树样本中检测到24种挥发物,总挥发量为54292 ng/h;而健康的对照枣树挥发物中只检测到14种化合物,总挥发量也仅为18611 ng/h。经SPSS软件分析,MeJA处理部分和对照部分,日本龟蜡蚧危害部分和对照部分这两组之间都达到差异显著水平。在上述挥发物成分中,萜烯类、醇类、酯类的增加量在植物诱导化学防御方面具有重要意义,这些化合物通常被认为是与吸引天敌昆虫相关的组分。     

华北落叶松枝叶挥发性物质的化学成分及其化感作用

采用气相色谱-质谱联用技术,分析了华北落叶松枝叶挥发物的化学成分及其对自身种子萌发、胚根和胚轴生长的化感作用.结果表明：华北落叶松挥发物中含量较大的化合物有20种,其中萜烯类及其含氧衍生物占较大比例,有5个单萜、12个倍半萜.华北落叶松枝叶挥发物对自身种子的萌发率、萌发速度指数、胚根和胚轴伸长量、鲜质量均具有显著抑制作用,表明华北落叶松挥发物中存在潜在的化感物质,并可能与挥发物中较高含量的萜类化合物有关.华北落叶松枝叶挥发物的化感作用影响自身的更新,是华北落叶松人工纯林退化的一个主要原因.