实夜蛾属二近缘种对寄主植物次生物质的反应:次生物质对幼虫生长和食物利用的影响

实夜蛾属(Heliothis)的棉铃虫(H. armigcra)和烟青虫(H. assulta)是近缘种,幼虫期取食多种相同的植物,其中含有不同的次生物质.本项工作是在人工饲料中分别加入0.5%的烟碱、番茄苷、棉子酚、丹宁酸等饲养早期六龄的幼虫,测定它们对生长和食物利用的影响.结果表明这些次生物质对两种幼虫有不同的作用:烟碱对棉铃虫没有明显影响,但对烟青虫的取食却有一定的刺激作用.丹宁酸、棉子酚、番茄苷可抑制两种幼虫的生长,而以番茄苷抑制烟青虫的生长最为显著.番茄苷主要通过抑制取食来影响幼虫的生长,而丹宁酸和棉子酚则具有降低消化率的作用.通过次生物质对这两种幼虫效应的比较可知,棉铃虫有较大的忍耐力.     

棉铃虫和烟青虫幼虫下颚栓锥感器对某些化合物反应特性的比较

利用电生理学技术,以两个食性有差异的近缘种棉铃虫和烟青虫为研究对象,比较研究了6龄幼虫下颚上两对栓锥感器对刺激取食素和抑食素的感受机理.结果表明:(ⅰ)两种幼虫栓锥感器对蔗糖和印楝素敏感的细胞均主要分布在侧栓锥感器,对肌醇敏感的细胞主要分布于中栓锥感器;(ⅱ)烟青虫幼虫中栓锥感器对肌醇刺激的反应敏感性强于棉铃虫;(ⅲ)在测试的6种抑食素中,仅印楝素在两种昆虫的侧栓锥感器上可诱导高的神经脉冲;(ⅳ)抑食素对刺激取食素引发栓锥感器神经脉冲有抑制作用,其中对于棉铃虫,辣椒素对蔗糖引发脉冲的抑制率最大,番茄苷对肌醇引发脉冲的抑制率最大,棉酚对蔗糖和肌醇引发脉冲的抑制率均为最小;对于烟青虫,单宁、棉酚和番茄苷对蔗糖引发脉冲均有较大的抑制率,棉酚对肌醇引发脉冲的抑制率最大,烟碱对蔗糖和肌醇引发脉冲的抑制率均为最小.     

棉酚和烟碱对棉铃虫的生长和细胞色素P-450单加氧酶活性的影响

以人工饲料添加法测定了 0 5%的棉酚和烟碱对棉铃虫的生长和细胞色素P 4 50单加氧酶 (简称P 4 50酶系 )活性的影响。研究结果显示 ,在测定浓度下 ,高龄棉铃虫短期取食含棉酚和烟碱的人工饲料后 ,对幼虫的生长没有显著影响 ,由此表明 ,棉铃虫对其主要寄主植物中的次生物质棉酚和烟碱具有很好的适应能力。与此同时 ,棉铃虫中肠微粒体P 4 50酶系的蛋白组成和酶活性发生了不同的变化 ,有升有降 ,有的没有变化。棉铃虫可能通过调整P 4 50酶系的各种蛋白含量和酶的活力水平 ,来适应对植物次生物质的代谢解毒的需要。另外 ,棉铃虫取食棉酚和烟碱后 ,细胞色素B5含量均显著提高 ,而细胞色素P 4 50含量均显著降低 ,细胞色素B5在棉铃虫对棉酚和烟碱的解毒代谢中可能发挥着更为重要的作用     

棉酚和烟碱对棉铃虫的生长和细胞色素P—450单加氧酶活性的影响

以人工饲料添加测定了0．5％的棉酚和烟碱对棉铃虫的生长和细胞色素P－450单加氧酶（简称P－450酶系）活性的影响。研究结果显示,在测定浓度下,高龄棉铃虫短期取食含棉酚和烟碱的人工饲料后,对幼虫的生长没有显著影响,由此表明,棉铃虫对其主要寄主植物中的次生物质棉酚和烟碱具有很好的适应能力。与此同时,棉铃虫中肠微粒体P－450酶系的蛋白组成和酶活性发生了不同的变化,有升有降,有的没有变化。棉铃虫可能通过调整P－450酶系的各种蛋白含量和酶的活力水平,来适应对植物次生物质的代谢解毒的需要。另外,棉铃虫取食棉酚和烟碱后,细胞色素B5含量均显著提高,而细胞色素P－450含量均显著降低,细胞色素B5在棉铃虫对棉酚和烟碱的解毒代谢中可能发挥着更为重要的作用。     

寄主植物轮换饲养和次生代谢物交叉涂布对棉铃虫取食的影响

食物混合通常对多食性昆虫的生长表现有积极的影响,然而此前的研究对象主要是成虫期和幼虫期迁移能力较强的种类。某些鳞翅目种类尽管是多食性的,但其幼虫个体因时空隔离的原因,并无机会自由选择食料寄主。采用寄主叶片轮换饲养和次生代谢物交叉涂布两种方法研究了多食性棉铃虫幼虫的取食行为,供试寄主植物包括烟草、辣椒、番茄和棉花,次生代谢物采用自然浓度进行交叉涂布。结果表明,食物混合并没有造成幼虫总体摄食量的显著增加。其中,烟草和水合烟碱能显著抑制棉铃虫对其他寄主叶碟的取食,而辣椒及(E)-辣椒素对其他寄主叶碟的被食量均无影响。番茄叶片轮换饲养不影响棉铃虫对与其轮换的其他寄主叶片的被食量,但α-番茄苷涂布在辣椒和棉花叶碟上则对棉铃虫有显著拒食作用。棉花-烟草轮换饲养组中的烟草被食量显著大于烟草非轮换组中的烟草被食量,但(+)-棉酚涂布处理却能显著抑制棉铃虫对烟草的摄食。两种生物测定方法均未发现棉花与辣椒存在显著性相互影响。总之,棉铃虫可能是以耐受式的对策适应寄主植物次生代谢物的,符合相称性形态构成假说,即扩散能力较差的鳞翅目幼虫个体并不需要进化出同时应对来自两种或两种以上的寄主植物次生代谢物的适应机制。     

植物次生代谢物对甜菜夜蛾生长发育及解毒酶的影响

【目的】明确植物次生代谢物对甜菜夜蛾Spodoptera exigua生长发育及解毒酶的影响,探索利用植物次生物质防控甜菜夜蛾的潜在途径。【方法】本研究选用3种含量（0.01%、0.1%和1.0%）的槲皮素、山奈酚和香豆素,分别与人工饲料混合均匀后饲养甜菜夜蛾3龄初幼虫,观察植物次生代谢物对幼虫生长发育的影响;并测定幼虫取食添加0.1%的槲皮素、山奈酚和香豆素的人工饲料24、48和72 h后,幼虫羧酸酯酶（Caboxylesterase,CarE）、谷胱甘肽-S-转移酶（Glutathione-S-transferase,GSTs）和P450解毒酶活性。【结果】添加不同次生物质的人工饲料显著影响甜菜夜蛾幼虫生长和解毒酶活性。与对照组相比,3种次生代谢物均显著提高了幼虫死亡率。幼虫取食添加1%槲皮素的人工饲料后,蛹重显著降低,发育历期明显延长。而取食添加0.1%山奈酚的人工饲料后,可诱导幼虫CarE活性显著增强,0.1%槲皮素和0.1%香豆素对幼虫CarE活性均有显著抑制作用。添加槲皮素对幼虫GSTs活性无显著性影响,添加0.1%山奈酚和0.1%香豆素可诱导幼虫GSTs活性显著升高。0.1%槲皮素和0.1%香豆素可促进幼虫P450活性增强但未达到显著水平,但0.1%山奈酚处理48h后,幼虫P450活性显著降低。【结论】植物次生代谢物种类与含量对甜菜夜蛾生长发育及解毒酶活性存在不同程度的影响。     

棉酚对棉铃虫生长及其寄生物齿唇姬蜂发育的影响(英文)

以中国北方棉区的主要害虫棉铃虫Helicoverpaarmigera（Hbner）及其内寄生蜂棉铃虫齿唇姬蜂Campoletischlorideae（Uchida）为试虫,研究了棉花重要抗虫次生性物质棉酚对棉铃虫生长和齿唇姬蜂发育的影响。0．1％的棉酚对棉铃虫幼虫有生长刺激作用,0．5％的棉酚则对棉铃虫幼虫生长有抑制作用。齿唇姬蜂成虫在寄生时对寄主大小有较严格的选择性,92％的被寄生幼虫体重小于18mg。0．1％的棉酚使寄主适合寄生期缩短10．75％;0．5％棉酚使寄主适合寄生期延长28．15％。棉酚对齿唇姬蜂发育有负效应。0．1％棉酚对寄主的生长刺激作用,不能使蜂成虫体重显著增加,但可显著延长蜂卵和幼虫期,缩短蛹期;高浓度的生长抑制作用,导致蜂成虫体重显著减轻,蛹期缩短,蜂卵和幼虫期亦显著延长。据此,对棉花抗虫性与生物防治在害虫综合防治实践中应用的协调性进行了讨论。     

番茄是烟青虫的寄主植物吗？

长期以来,国内有关文献一直将番茄列为烟青虫Helicoverpa assulta的寄主植物,但田间调查结果往往与此矛盾,本研究的目的是阐明番茄是否为烟青虫的寄主植物。室内试验表明,虽然烟青虫成虫在盆栽番茄植株上产卵较多,但无论是用番茄离体嫩叶还是用盆栽植株饲养,初孵幼虫绝大部分在1龄死亡,平均存活时间很短,不会对番茄造成有经济意义的危害;即使用番茄青果饲养的3龄幼虫也不能活到6龄。根据人工饲料饲养结果估测,番茄苷对初孵幼虫的致死中浓度LC₅₀为0.0744%,叶和青果中报道的番茄苷含量已接近或超过此水平,这是幼虫不能存活的主要原因之一。田间调查也表明,烟青虫并不危害番茄。因此,番茄不是烟青虫的寄主植物。文献中的记载很可能是将棉铃虫误判为烟青虫。     

大豆胰蛋白酶抑制剂与棉酚或丹宁混用对棉铃虫中肠蛋白酶和生长率的影响

本文报告了大豆胰蛋白酶抑制剂(STl)与棉酚、丹宁酸单一和协同作用对棉铃虫Helicoverpa armigera(Hubner)幼虫中肠蛋白酶活性和生长速率的影响。在离体条件下,STI、棉酚和丹宁酸均对中肠蛋白酶有抑制作用,以STI的作用最强。活体试验表明,人工饲料中0.84%(干重)的S丁I对强碱性类胰蛋白酶活力有显著抑制作用;0.3%丹宁酸则对弱碱性类胰蛋白酶和总蛋白酶活力有显著抑制作用;0.3%棉酚对几种蛋白酶活力的影响均不显著。三者均能显著抑制幼虫的生长,而Sn与棉酚或丹宁酸的协同作用比三者的单独作用更能有效地抑制幼虫的生长发育和中肠蛋白酶活性。     

大豆胰蛋白酶抑制剂与棉酚或丹宁混用对棉铃虫中肠蛋白酶和生长率的影响

本文报告了大豆胰蛋白酶抑制剂(STl)与棉酚、丹宁酸单一和协同作用对棉铃虫Helicoverpa armigera(Hubner)幼虫中肠蛋白酶活性和生长速率的影响。在离体条件下,STI、棉酚和丹宁酸均对中肠蛋白酶有抑制作用,以STI的作用最强。活体试验表明,人工饲料中0.84%(干重)的S丁I对强碱性类胰蛋白酶活力有显著抑制作用;0.3%丹宁酸则对弱碱性类胰蛋白酶和总蛋白酶活力有显著抑制作用;0.3%棉酚对几种蛋白酶活力的影响均不显著。三者均能显著抑制幼虫的生长,而Sn与棉酚或丹宁酸的协同作用比三者的单独作用更能有效地抑制幼虫的生长发育和中肠蛋白酶活性。     

Comparative study on the responses of maxillary sensilla styloconica of cotton bollwormHelicoverpa armigera and Oriental tobacco budwormH. assulta larvae to phytochemicals

Using the electro-physiological technique, the sensory mechanisms of maxillary sensilla styloconica to stimulants and deterrents were explored on two closely related species, the generalist Helicoverpa armigera and the specialist H. assulta. The results showed that: (i) in both species, cells sensitive to sucrose and azadirachtin were mainly in the lateral sensillum styloconicum, and those to inositol were in the medial sensillum styloconicum; (ii) sensitivity of medial sensillum styloconicum in H. assulta to inositol was higher than that in H. armigera; (iii) among 6 tested deterrents, only azadirachtin evoked high impulse discharge from the lateral sensillum styloconicum in both insects; (iv) the deterrents could disturb stimulants evoking impulse discharge from maxillary sensilla styloconica of both species in different degrees: To sucrose evoking impulses on lateral sensillum styloconicum, for H. armigera capsaicin had a strong inhibition and gossypol had a weak inhibition, while for H. assulta tann     

Metabolic detoxification of capsaicin by UDP-glycosyltransferase in three Helicoverpa species

Capsaicin β-glucoside was isolated from the feces of Helicoverpa armigera, Helicoverpa assulta, and Helicoverpa zea that fed on capsaicin-supplemented artificial diet. The chemical structure was identified by NMR spectroscopic analysis as well as by enzymatic hydrolysis. The excretion rates of the glucoside were different among the three species; those in the two generalists, H. armigera and H. zea, were higher than in a specialist, H. assulta. UDP-glycosyltransferases (UGT) enzyme activities measured from the whole larval homogenate of the three species with capsaicin and UDP-glucose as substrates were also higher in the two generalists. Compared among five different larval tissues (labial glands, testes from male larvae, midgut, the Malpighian tubules (MT), and fat body) from the three species, the formation of the capsaicin glucoside by one or more UGT is high in the fat body of all the three species as expected, as well as in H. assulta MT. Optimization of the enzyme assay method is also described in detail. Although the lower excretion rate of the unaltered capsaicin in H. assulta indicates higher metabolic capacity toward capsacin than in the other two generalists, the glucosylation per se seems to be insufficient to explain the decrease in capsaicin in the specialist, suggesting that H. assulta might have another important mechanism to deal with capsaicin more specifically.     

Using COI gene sequence to barcode two morphologically alike species: the cotton bollworm and the oriental tobacco budworm (Lepidoptera: Noctuidae)

Due to limited morphological difference, the two closely related sister species, the cotton bollworm, Helicoverpa armigera (Hübner) and the oriental tobacco budworm, H. assulta (Guenée) (Lepidoptera: Noctuidae), are very difficult to distinguish, especially at the larvae stage. Recently, DNA sequence has been widely used as a bio-barcode for species identification. In this study, we attempted to distinguish H. armigera and H. assulta using the mitochondrial cytochrome C oxidase subunit I gene (COI) gene sequence as the barcode. We determined a 658 bp segment of the COI gene for 28 individuals of H. armigera, 8 individuals of H. assulta, and 10 individuals of Mamestra brassicae (as the outgroup) in Yunnan Province, southwest of P. R. China, together with one H. assulta and two H. armigera reported sequences from GenBank. Twenty-three haplotypes were identified in all 49 samples. As expected, network analysis of the haplotypes of the three species presented a clustering pattern consistent with the respective species status. Haplotypes of the same species differed from each other by no more than three nucleotide substitutions. However, each haplotype of H. armigera differed from that of H. assulta by at least 22 nucleotide substitutions. Both species differed from M. brassicae by more than 50 nucleotide substitutions. 17 unique diagnostic nucleotides were also used to discriminate the two species. The finding of large COI sequence differences between H. armigera and H. assulta suggested that it could be used to distinguish the two morphologically alike species and be employed for quick species identification during pest control.     

Mechanisms of premating isolation between Helicoverpa armigera (Hübner) and Helicoverpa assulta (Guenée) (Lepidoptera: Noctuidae)

Helicoverpa armigera and Helicoverpa assulta are sympatric sibling species, and in the laboratory they can interbreed and produce viable offspring. To assess the contributions of temporal barriers and sexual barriers to premating isolation, we investigated both the temporal rhythms of calling behavior and pheromone titers of H. armigera and H. assulta females and the behavioral responses of males to conspecific and heterospecific calling females in a wind tunnel. Both H. armigera and H. assulta females called throughout the scotophase, and there was more calling during the second half of the scotophase than during the first half. Maximal pheromone titer and maximal calling activity in H. armigera synchronously occurred at the sixth hour into the scotophase, whereas, in H. assulta, the maximal pheromone titer occurred 2 h before the peak of calling. Pheromone blend ratios of the two species were opposite and, within each species, changes in the ratio within the scotophase and at different ages were relatively small. Males of both H. armigera and H. assulta responded strongly to their conspecific calling females in the wind tunnel and completed the whole courtship sequence. In contrast, they did not land and had no copulation attempts in response to heterospecific calling females. These results show that the two species do not have obvious temporal differences in calling behavior and pheromone production, and the specificity of sex pheromone blend emitted by females plays a key role in their premating isolation. In addition, we summarized the potential isolation mechanisms of H. armigera and H. assulta.     

烟草挥发物对2近缘种夜蛾产卵行为的影响及其成分分析

寡食性烟夜蛾Helicoverpa assulta (Guenée)和广食性棉铃虫H.armigera (Hübner)是铃夜蛾属2近缘种,烟草是其共同寄主.室内实验测定了1个普通烟草品种和4个黄花烟草品种叶片挥发物对二者电生理和行为反应的影响.结果表明,烟夜蛾处女雌蛾和交配雌蛾对4个黄花烟草品种叶片挥发物的EAG反应均显著高于普通烟草,而棉铃虫对普通烟草叶片挥发物的反应显著高于黄花烟草;二者的行为反应与EAG测试结果相似,黄花烟草叶片挥发物对烟夜蛾有较强的引诱作用,棉铃虫对普通烟草叶片挥发物有较强趋性;两种夜蛾雄蛾对这些挥发物的EAG和行为反应均没有雌蛾强烈,性别差异显著;GC-MS分析表明,与K326相比,马合烟叶片挥发物中尼古丁的相对含量高(76.91%),绿叶气味种类多但芳香族化合物种类少,挥发物种类和含量的不同是否与两种夜蛾产卵趋性差异相关,有待进一步研究.     

棉铃虫不同寄主种群遗传分化的RAPD分析

应用RAPD技术对生活于辣椒,烟草和番茄3种不同寄主上的棉铃虫（Helicover pa armigera)种群,并以烟草烟青虫（H.assulta)为外群进行了种群遗传分化的研究,研究结果表明：4个处理内个体间最大的遗传距离均小于处理间最小的遗传距离,烟青虫的遗传距离为0．177－0．346,棉铃虫的辣椒种群为0．289－0．404,烟草种群为0．396－0．505,番茄种群为0．329－0．382,采用UPDGA法进行聚类,并构建系统发育树。各处理成聚的遗传距离为：烟青虫是0．334,棉铃虫的辣椒种群是0．372,烟草种群是0．463,番茄种群是0．360。各处理均首先成聚,棉铃虫与烟青虫成聚的遗传距离（0．703）,稍大于棉铃虫各种群的成聚值（0．639）。上述结果表明,棉铃虫不同寄主种群已经存在明显的遗传分化。     

Hybridization between Helicoverpa armigera and Helicoverpa assulta (Lepidoptera: Noctuidae): development and morphological characterization of F1 hybrids

Reciprocal hybridizations between Helicoverpa armigera (Hübner) and Helicoverpa assulta (Guenée) were studied. The cross between females of H. armigera and males of H. assulta yielded only fertile males and sterile individuals lacking an aedeagus, valva or ostium bursae. A total of 492 larvae of the F1 generation were obtained and 374 of these completed larval development and pupated. Only 203 pupae were morphologically normal males, the remaining 171 pupae were malformed. Larvae and pupae that gave rise to morphologically abnormal adults exhibited longer development times. Sterility was not only associated with malformed external sex organs, but also a range of abnormalities of the internal reproductive system: (i) loss of internal reproductive organs, (ii) with one to three copies of an undeveloped bursa copulatrix; or (iii) with one or two undeveloped testes. Normal male hybrid adults showed higher flight activity in comparison with males of both species. In contrast, the cross between females of H. assulta and males of H. armigera yielded morphologically normal offspring (80 males and 83 females). The interaction of the Z-chromosome from H. assulta with autosomes from H. armigera might result in morphological abnormalities found in hybrids and backcrosses, and maternal-zygotic incompatibilities might contribute to sex bias attributed to hybrid inviability.     

Genetic basis of sex pheromone blend difference between Helicoverpa armigera (Hübner) and Helicoverpa assulta (Guenée) (Lepidoptera: Noctuidae)

The two closely related moth species, Helicoverpa armigera and H. assulta, are sympatric in China. Both species use a mixture of (Z)-11-hexadecenal (Z11-16:Ald) and (Z)-9-hexadecenal (Z9-16:Ald) as their sex pheromones but in widely different ratios. Hybridization and backcrossing experiments between H. armigera and H. assulta were conducted and sex pheromone compositions of the parent species, their F(1) hybrids and backcrosses were compared to study the genetic basis of the production of their sex pheromone blend composition. Results show that the difference in sex pheromone blend ratios of these Helicoverpa species is mainly controlled by an autosomal locus with two alleles, with the allele from H. armigera being almost completely dominant over that derived from H. assulta.     

21种杀虫剂和3种植物次生物质对杨扇舟蛾各组织谷胱甘肽S-转移酶的抑制作用

为了比较杨扇舟蛾Clostera anachoreta (Fabricius)各组织谷胱甘肽S 转移酶（GSTs）的差异,利用分光光度酶动力学的方法,研究了21种杀虫剂和3种植物次生物质对杨扇舟蛾4个组织（中肠、脂肪体、头部和体壁）GSTs活性的体外影响。结果表明:21种杀虫剂和3种植物次生物质对杨扇舟蛾4个组织GSTs活性的抑制作用不同。毒死蜱、氟虫腈、槲皮素和单宁酸对于杨扇舟蛾头GSTs活性抑制作用最强;槲皮素和单宁酸对中肠GSTs活性的抑制作用最强;单宁酸对脂肪体GSTs活性的抑制作用最强;辛硫磷、高效氯氟氰菊酯、溴氰菊酯和硫丹对皮GSTs活性的抑制作用最强。杨扇舟蛾4个组织GSTs对杀虫剂和植物次生物质敏感性存在的这种差异,可能是由于其在同工酶组成上的差异造成的。