不同生物型棉蚜对夏寄主葫芦科作物的选择

于2008、2009年连续两年采用模拟田间自然扩散法,系统地研究了棉花型棉蚜和甜瓜型棉蚜有翅蚜对11种夏寄主的选择性.结果表明,棉花型棉蚜对杂交葫芦、小西葫芦表现出强选择性及适应性,而对香瓜、黄瓜、西瓜及甜瓜均不选择,或即使选择其若蚜在其上也不能存活;甜瓜型棉蚜对甜瓜、香瓜、南瓜、黄西葫芦、大西葫芦、杂交葫芦等均表现较强选择性,而对棉花及小西葫芦表现不选择.但是,甜瓜型棉蚜在小西葫芦上也能产若蚜并存活.从而证明小西葫芦是两种寄主型棉蚜的共同寄主,有可能成为两者相互转换的桥梁寄主.     

不同棉蚜种群对棉花和黄瓜的适合度分化

通过室内转接试验,研究来源于越冬寄主花椒、木槿、石榴和夏寄主棉花、黄瓜共5个棉蚜Aphids gossypii Glover种群对棉花和黄瓜的适合度。结果表明:花椒棉蚜、木槿棉蚜、棉花棉蚜转接到棉花上的成虫留居率和种群繁殖率均明显地高于黄瓜;黄瓜棉蚜转接到棉花上的成虫留居率和种群繁殖率均显著地低于黄瓜;石榴棉蚜转接到棉花上的种群繁殖率显著低于黄瓜,但成虫留居率在2种寄主之间没有明显差异。     

棉花型和黄瓜型棉蚜(Aphis gossypii Glover)的寄主适应性及转移通道

采用寄主转接建立生命表的方法研究了棉花型和黄瓜型棉蚜对不同寄主植物的适应性,以及两寄主型棉蚜是否可通过中间桥梁寄主实现寄主互换的问题。结果表明,两寄主型棉蚜直接互换寄主后,其存活和繁殖力显著下降,表现为棉花型和黄瓜型棉蚜的净增殖率比在原寄主上分别下降980倍和12倍,平均世代寿命缩短5～12d。两寄主型棉蚜均能利用木槿植物,并且适应性没有显著差异。但是两寄主型棉蚜均不能在车前草和大叶黄杨上存活和繁殖后代。西葫芦作物对棉蚜在木槿、棉花和黄瓜寄主上的相互转移起到了重要的桥梁寄主作用。冬寄主木槿上棉蚜可通过甜瓜或西葫芦转移到黄瓜寄主上,棉花和黄瓜上棉蚜也可通西葫芦作物分别转移到黄瓜和棉花作物上,从而形成棉蚜在不同寄主植物间的相互转移通道,造成为害和病毒病的扩张。     

棉花型和黄瓜型棉蚜对寄主植物的适合度

采用寄主转换建立生命表及触角电位 (EAG)方法比较了棉蚜两寄主专化型 (棉花型和黄瓜型 )对不同夏季作物的适合度。结果表明 ,棉花型蚜转到黄瓜上及黄瓜型蚜转接到棉花上均不能正常产仔繁殖和建立种群。两种蚜型均不能在茄子和苋菜上建立种群。黄瓜型蚜能在豇豆上建立种群 ,但棉花型蚜不能 ,表现出两种寄主型棉蚜对夏寄主利用上存在显著差异。受棉蚜为害 12～ 36 h后的黄瓜或棉花植株仍不适合于棉花型或黄瓜型蚜 ,表现出黄瓜型蚜不能在被棉花型蚜为害过的棉株上正常存活和繁殖 ,棉花型蚜也不能在被黄瓜型蚜为害过的黄瓜苗上存活和繁殖。两种寄主型蚜对不同寄主叶片丙酮提取物的触角电位表明 ,黄瓜型蚜对棉花、哈密瓜和马铃薯叶片提取物的反应显著强于棉花型蚜 ,而对黄瓜和甜瓜叶片提取物的反应上两种蚜型差异不显著。文中同时对棉花型和黄瓜型棉蚜产生的生态机制进行了讨论。     

5个棉蚜组织蛋白酶B基因克隆及在不同寄主专化型中的表达分析

昆虫组织蛋白酶B在昆虫代谢中发挥着重要作用。本研究从棉蚜Aphis gossypii Glover的转录组数据库中挑选Cath B并克隆得到全长cDNA序列,使用qRT-PCR分析这些基因在不同寄主专化型棉蚜不同龄期中的相对表达量。通过分析棉蚜体内5个高表达组织蛋白酶B基因不同发育阶段的表达谱,比较了不同专化型棉蚜在寄主转换之后的表达差异。研究发现,这5个基因在不同龄期不同寄主上均表达。棉花型棉蚜在棉花寄主上不同基因间的表达各不相同。黄瓜型棉蚜在黄瓜Cucumis sativus L.上AgCb-1、AgCb-2、AgCb-3基因均在成蚜时期表达量相对较高,AgCb-4、AgCb-5基因表达量则与之相反。分别将棉花型棉蚜和黄瓜型棉蚜转接到西葫芦Cucurbita pepo L.上后,棉花型棉蚜AgCb-1、AgCb-4基因和黄瓜型棉蚜AgCb-1、AgCb-2、AgCb-3基因均在成蚜不同时期的表达量显著大于转接前。结果表明：AgCb-1、AgCb-2、AgCb-3、AgCb-4、AgCb-5基因表达量伴随着棉蚜的生长发育以及寄主的转换,表现出不同的差异。说明组织蛋白酶在棉蚜对寄主植物的适应性过程中可能发挥作用。     

棉蚜寄主专化型及其形成的行为机理

通过生活在甜瓜和棉花上的棉蚜Aphisgossypii Glover的行为,研究棉蚜的寄主专化型及其形成的行为机理。生物学观察显示： 两类棉蚜在寄主植物相互交换以后,定居数显著减少,棉花蚜型棉蚜的繁殖系数及若虫存活率显著下降,说明棉蚜存在甜瓜蚜型和棉花蚜型两种寄主专化型。通过刺探电位技术研究棉蚜的取食行为,以探索其寄主专化型形成的行为机理。结果表明： 甜瓜蚜型棉蚜在棉花上的取食行为容易被中断,但其口针定位韧皮部的能力并没有显著削弱;而棉花蚜型棉蚜在甜瓜上的取食行为受到更大的影响,口针无法顺利定位至韧皮部,并在2 h内根本无法在筛管内取食。生物学观察和EPG取食行为分析都显示： 与甜瓜蚜型棉蚜相比,棉花蚜型棉蚜对寄主的要求更严格-寄主专化程度更高,对寄主的利用率更高。     

6种寄主果实对南瓜实蝇和瓜实蝇产卵选择 及其子代发育的影响

为探讨南瓜实蝇和瓜实蝇对不同寄主的产卵选择性及其与子代生长发育的关联度,采用生态测定方法,研究2种实蝇对南瓜、黄瓜、姜柄瓜、西葫芦、丝瓜和苦瓜6种寄主果实的产卵选择以及幼虫取食6种寄主后对其生长发育的影响。在产卵选择性试验中,2种实蝇对6种寄主的产卵选择性较为一致,均偏向于在丝瓜和黄瓜上产卵。在非产卵选择性试验中,南瓜实蝇在黄瓜和姜柄瓜上的产卵量较多;瓜实蝇在丝瓜和姜柄瓜上的产卵量较多;2种实蝇都对姜柄瓜有一定的偏好。在气味诱导的产卵选择性试验中,南瓜实蝇在姜柄瓜和黄瓜上的产卵量较多;瓜实蝇在黄瓜和丝瓜上的产卵量较多;2种实蝇都对黄瓜气味有一定的偏好;且南瓜实蝇和瓜实蝇都不偏好在苦瓜上产卵。南瓜实蝇分别取食黄瓜、苦瓜时,其幼虫期、蛹期较短;取食姜柄瓜时,蛹重最大;分别取食南瓜和黄瓜时的化蛹率、羽化率最高。瓜实蝇取食西葫芦时,幼虫期较短;取食丝瓜时,蛹期较短,且蛹重最大;分别取食黄瓜和南瓜时的化蛹率、羽化率最高。南瓜实蝇和瓜实蝇对不同寄主果实的产卵选择性均存在明显差异,寄主外部物理性状对实蝇的产卵选择有显著影响,2种实蝇对6种寄主果实产卵选择性和幼虫生长发育适应性的相关性不显著。     

棉蚜唾液蛋白C002基因克隆及在棉蚜不同寄主专化型中的表达分析

C002是蚜虫取食过程中的一种十分重要的水溶性唾液蛋白。本研究从棉蚜的转录组数据中,克隆得到棉蚜C002基因的c DNA序列(Gen Bank登录号:AHX71991.1)。C002基因的开放阅读框全长为641 bp,编码213个氨基酸,推测其蛋白质的分子质量为24.1 k Da,等电点为9.06,具有由24个氨基酸组成的信号肽。运用荧光定量PCR技术,分析棉花型棉蚜和黄瓜型棉蚜的时间表达谱,结果表明,C002基因在两种寄主专化型棉蚜生长发育的早期阶段表达量均较高。将棉花型棉蚜和黄瓜型棉蚜分别转接到西葫芦后,C002基因的表达量在转接前后无显著变化,说明C002基因在棉蚜适应寄主过程中并没有起到关键性作用。     

田间中间寄主豇豆对专化型棉蚜的影响

中间寄主植物在植食性昆虫的取食选择和进化方向上起着重要的作用。本研究在田间设置罩笼,结合生态学调查和生物型鉴定技术研究了中间寄主豇豆对棉花型棉蚜和黄瓜型棉蚜专化性的影响。研究结果表明,棉花型棉蚜在豇豆上需经过1周时间的适应才能在豇豆上繁殖并在接虫后的第31天达到峰值(1 019±191头/百株),但不能够继续转移到黄瓜上建立种群;黄瓜型棉蚜在豇豆上在接虫后的第11天首次被记录后,其种群密度就迅速增加,到接虫后的第28天达到种群数量最大值(16 810±2 966头/百株),但也未能成功转移到棉花上存活并建立种群。在本实验研究条件下,中间寄主豇豆不能够改变棉花型棉蚜对棉花的偏好性,也不能在短期内改变黄瓜型棉蚜对黄瓜的专化性。     

棉花型和瓜型棉蚜产生有性世代能力的分化

为了明确寄主专化性是否会影响棉蚜的繁殖策略或生活史对策,采用低温和短光照组合（18℃,L∶D=8∶16）分别对棉花型和瓜型棉蚜进行有性世代的诱导,比较两寄主专化型棉蚜产生有翅蚜、雄性母、雌性母及无翅孤雌蚜的能力。结果表明：两寄主专化型棉蚜在产生有性世代能力上存在显著差异,表现为棉花型棉蚜在诱导后代中产生有翅蚜、雄性母和雌性母的比率显著高于瓜型棉蚜,并且雌、雄性母产生的时间明显早于瓜型棉蚜。瓜型棉蚜在诱导条件下产生无翅孤雌蚜的比率显著高于棉花型棉蚜,并且发现有不产生有性世代的营专性孤雌生殖个体,而在棉花型棉蚜中没有发现。产生性母蚜的棉花型和瓜型棉蚜均可同时产生孤雌胎生后代。寄主型与诱导时间长短对棉蚜有性世代的产生存在交互作用。采集于田间棉花和黄瓜上的棉蚜,也表现为棉花上的易产生有性世代,在诱导的第2代中产生性母蚜的比率显著高于黄瓜上的棉蚜,并且性母蚜比率在诱导的第2代与第3代间无显著差异; 但黄瓜上的棉蚜性母蚜产生比率第3代显著高于第2代。由此推测,棉蚜寄主专化性的形成与生活史特性的分化有关。     

Effect of reproductive mode on host plant utilization of melon aphid (Hemiptera: Aphididae)

Variation in the reproductive mode of melon aphid Aphis gossypii Glover occurred on the large geographic scale, but the performance of different reproductive modes to use host plant is poorly understood. Life tables of melon aphid population that undergo the anholocyclic, androcyclic, and intermediate reproductive mode were conducted on different host plants. The results showed that the anholocyclic and androcyclic strains could become adults and produce offspring on cotton Gossypium hirsutum L., whereas the intermediate strain could not. The survival rate, net reproductive rate (R(0)), and intrinsic rate of natural increase (r(m)) of the androcyclic strain on cotton were significantly greater than that of the anholocyclic strain. The three strains could aptly use cucurbits host plants including cucumber Cucumis sativa L., pumpkin Cucurbita moschata (Duchesne ex Lam.), and zucchini Cucurbita pepo L.; survival rate and R(0) were not significantly different on these two host plants. Moreover, the r(m) of the anholocyclic strain on cucumber and the androcyclic strain on pumpkin and zucchini were significantly greater than that of the other two strains. The abilities of the three strains to use a host plant were flexible, because their r(m) on pumpkin or zucchini became equal after rearing for four successive generations; furthermore, the intermediate strain attained the ability to use cotton, and the performance of anholocyclic and intermediate strains to use cotton also significantly increased after feeding on pumpkin or zucchini for one or three generations. It was concluded that the reproductive mode and feeding experience affected the performance of melon aphid to use a host plant.     

How does the host‐specialized aphid deal with food deficiency?

Aphis gossypii Glover shows obvious host specialization, with cucurbit‐ and cotton‐specialized biotypes or host races in many regions. Because its annual natal host crops senesce earlier the cucurbit‐specialized biotype may suffer food deficiency. The method this biotype uses to overcome this challenge is still poorly understood. In order to understand the potential of the cucurbit‐specialized biotype aphids in host shift and usage, the performance of this biotype on cotton (Gossypium hirsutum), a common but poor quality host plant, was explored in this study. The cucurbit‐specialized aphids could establish populations on cotton only when these plants had at least nine leaves, and subsequent populations developed rather slowly. The presence of whitefly populations on cotton improved the success rate of cucurbit‐specialized aphids. The cucurbit‐specialized aphids were mainly distributed on the older leaves of cotton, with only a few settling on the upper leaves. The cucurbit‐specialized aphids reared on cotton for 40, 54 and 61 days still maintained strong preference for their natal host plant, cucumber (Cucumis sativus), rather than cotton, and their net reproductive rates and intrinsic rates of natural increase were dramatically lower when they were transferred onto new six‐leaf cotton plants or detached leaves. Therefore, we concluded that the cucurbit‐specialized aphids have the potential to utilize mature or whitefly‐stressed cotton plants, but that this feeding experience on cotton did not alter their specialization for cucurbits. Some cotton plants could act as a temporary host for the cucurbit‐specialized aphids to overcome food deficiency arising from senescing cucurbits.     

取食不同寄主植物对棉蚜后代抗药性的影响

测定了5种药剂对棉蚜Aphis gossypii抗氰戊菊酯、吡虫啉品系和敏感品系取食棉花、黄瓜和石榴的后代的毒力,并对它们的后代体内乙酰胆碱酯酶和羧酸酯酶的比活力做了初步探索。结果表明,氰戊菊酯抗性品系取食棉花比取食黄瓜的后代对氰戊菊酯的抗性大76.4倍,对灭多威、氧乐果、硫丹和吡虫啉的抗性也大0.5～4.6倍;取食石榴的后代对5种药剂的抗性介于取食棉花和黄瓜的之间。吡虫啉抗性品系的测定结果与氰戊菊酯抗性品系基本一致。敏感品系取食黄瓜比取食棉花的后代对5种药剂的敏感性更高。3个品系取食不同植物的后代相比,其体内乙酰胆碱酯酶的比活力,取食棉花的为取食黄瓜的2.4～2.8倍;羧酸酯酶的比活力,取食棉花的为取食黄瓜的1.8～2.4倍。证明棉蚜的抗性和敏感品系取食的寄主植物不同,可引起对药剂敏感性的变化。乙酰胆碱酯酶和羧酸酯酶活力的变化均是引起这种变化的重要因素。     

棉花型和瓜型棉蚜形态和生态适应力的分化

棉蚜由于长期在同种或同类植物上生活,形成了多种寄主专化型。本研究以室内长期用单一寄主培养的棉花型和瓜型棉蚜为材料,采用形态测定、生命表技术、对寄主的选择性试验,以及接触刺激等方法,研究了两寄主型棉蚜的形态分化和生态适应力的差异。结果表明,瓜型棉蚜的一些形态特征值（如体长）极显著地大于棉花型个体,但是头宽、口针和各腿节的长度与体长的比值却极显著的小于棉花型个体。采用7个形态指标与体长的比值,可将瓜型和棉花型棉蚜区分开来。在24℃和26℃下瓜型蚜的净增殖率（R₀）极显著地高于棉花型蚜。27℃和32℃显著缩短了瓜型蚜的平均世代长度,而对棉花型蚜无影响。棉花型蚜对接触刺激的反应比瓜型蚜敏感。两寄主型蚜对寄主的选择能力表现为瓜型蚜显著强于棉花型蚜。因此,两寄主型棉蚜存在明显的形态和生态适应力的分化。     

Specialized host-plant performance of the cotton aphid is altered by experience

Although distinct host specialization is observed for the cotton-melon aphid (Aphis gossypii Glover) on cotton and cucurbit plants, it is still ambiguous whether the specialization is altered by experience on a novel host plant. Here the performance of cotton and cucurbit-specialized aphids, A. gossypii on novel host plants was studied by a host-selection test and by the life-table method. The two host-specialized aphids cannot survive and establish populations after reciprocal host transfers. They have ability to recognize the host plants on which they were reared, and escape behavior from novel hosts was observed. Interestingly, the cotton and cucurbit-specialized aphids survive and reproduce normally on hibiscus (Hibiscus syriacus), a main overwintering host plant, and host-fidelity of A. gossypii to cucurbit plants is altered by feeding and living experience on hibiscus, which confers the same capacity to use cotton and cucumber on to the cucurbit-specialized population, but host-fidelity to cotton is not altered and the fitness of the cotton specialized population to cucumber is still poorer. A. gossypii from hibiscus has a significant preference for cotton to cucumber in the host-selection process, and none stays on cucumber more than 20 h after transfer. The results presented imply that cucurbit-specialized aphids might not return to an overwintering host plant (hibiscus) in wild fields, so host conservatism to cucurbit plants is maintained. The potential of cucurbit-specialized aphids of A. gossypii to use cotton plants, intermediated by experience on hibiscus, suggests that the specialized host-plant performance of phytophagous insects is not wholly conservative.     

黑带食蚜蝇成虫室内的饲养方法

对黑带食蚜蝇成虫所需的饲养空间、光照及补充营养物初步进行了筛选 ,并探讨了蚜虫、寄主植物及补充营养物对其成虫产卵的影响。结果表明 ,在 3 0cm× 3 0cm× 3 0cm养虫笼内同时提供大麻、玉米和油菜 3种鲜花粉并辅以光照饲养效果最佳 ,平均每雌产卵量 468粒 ,最高达 70 1粒 ,孵化率88 4%,产卵前期 1 1 5d ,雌雄成虫寿命分别为 5 5 5和 5 6 8d。试验还表明 ,提供蚜虫及其寄主植物可使成虫正常产卵 ,带蚜的莲花白叶片作为其成虫产卵载体植物着卵量最高     

3种寄主上桃蚜的选择性及形态分化

桃蚜是一种重要的农业害虫,寄主广泛,种下分化复杂。以采自黄土高原旱作区桃树、烟草、甘蓝上的桃蚜为研究对象,通过叶片选择法、传统比较形态测定法研究了3种寄主上桃蚜的选择性及形态分化。结果表明:在3种寄主同时存在的情况下,烟草上的桃蚜嗜食烟草,表现为63.5%的桃蚜选择烟草叶,13.8%选择甘蓝叶,8.2%选择桃叶,而甘蓝和桃树上的桃蚜对原寄主没有表现出明显的嗜好性;从形态指标来看,3种寄主上的桃蚜在体长、触角末节长度、后足腿节长度、触角与体长的比例方面存在显著差异(P0.05),说明这几个特征可以作为区分这3种寄主上桃蚜的依据。综合分析可以初步认为黄土高原旱作区烟草上的桃蚜可能形成了寄主专化型-烟草型。     

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.