【作者】 张莹；

【导师】 吴孔明；

【作者基本信息】 中国农业科学院 ， 农业昆虫与害虫防治， 2009， 博士

【摘要】 大豆蚜Aphis glycines(Matsumura)是栽培大豆Glycine max(L.)的主要害虫之一,通过刺吸危害和传播植物病毒,常引起大豆的品质下降和产量损失,严重发生时可造成减产50%以上。自2000年大豆蚜入侵美国后,在短短的几年内迅速扩散到美国和加拿大的部分大豆种植区,造成当地大豆的大量减产,并有继续蔓延危害的趋势。有翅蚜在寄主条件恶化,种群密度过高的情况下,依靠自主飞行和气流携带两种方式寻找新的生境和寄主植物,以此对大豆造成大面积危害。生物防治可以有效地抑制大豆蚜的危害,其中,寄生蜂是控制蚜虫种群的重要生物因子。在蚜虫和寄生蜂的互作关系和协同进化中,寄生蜂可以随寄主蚜虫的迁飞而进行远距离的扩散。研究寄生蜂随有翅蚜迁飞扩散而进行传播的潜力,以明确寄生蜂的扩散能力,将对大豆蚜的生物防治有重要意义。本文首先研究了大豆蚜的飞行能力及飞行对生殖的影响,在此基础上,通过被寄生蚜虫的模拟飞行试验,测定被寄生有翅蚜的飞行能力以及寄主的飞行对寄生蜂生长发育和羽化的影响,主要研究结果如下:大豆蚜具有较强的飞行能力。羽化后12h和24h的个体,飞行能力最强,平均飞行距离分别达5.11km和4.62km,羽化后72h的有翅蚜飞行能力急剧下降。温、湿度对飞行能力影响较大,大豆蚜在16oC-28oC下飞行能力较强,而低温(12oC)和高温(32oC)不利于飞行;适宜飞行的相对湿度为60%-90%RH。飞行对大豆蚜的生殖有明显的影响。飞行距离>2.5km的有翅蚜,其生殖量、生殖期和寿命明显降低,而生殖后期显著延长。有翅蚜的飞行对其后代蚜虫的生殖也产生了明显的影响,表现为远距离飞行>1.5km的有翅蚜后代与近距离(<1.5km)飞行的相比,生殖量、种群净增殖率显著降低。棉蚜蚜小蜂Aphelinus varipes可随大豆蚜的飞行进行远距离的扩散传播。棉蚜蚜小蜂的寄生抑制3龄有翅若蚜翅的发育,仅有35%的3龄若蚜能够发育为正常的翅,而4龄有翅若蚜翅的发育不受影响,100%的4龄有翅若蚜都能发育为正常的翅。4龄有翅若蚜和有翅蚜被寄生后仍能进行远距离的飞行,寄生24h和48h后,蚜虫的飞行能力没有受到影响,而寄生72h和96h后,蚜虫的飞行能力急剧下降。寄生蜂的幼虫发育历期、蛹发育历期、僵蚜形成率和寄生蜂羽化率不受寄主蚜虫飞行(0 km、<1 km、1-3 km和3-5 km)的影响。棉蚜刺茧蜂Binodoxys communis可随大豆蚜(夏季种群和秋季性母)的飞行进行远距离的扩散传播。棉蚜蚜茧蜂寄生有翅若蚜后,仅3龄蚜虫翅的发育受到影响,而4龄蚜虫完全不受影响,都能够发育为具有飞行能力的正常翅。在大豆蚜夏季种群中,4龄有翅若蚜被寄生后仍能进行远距离的飞行,寄生24h和48h后,蚜虫的飞行能力没有受到影响,而寄生72h和96h后,蚜虫的飞行能力急剧下降,而且幼虫发育历期、蛹发育历期、僵蚜形成率和寄生蜂羽化率不受寄主蚜虫飞行(0h、0.5h、1h和2h)的影响。性母若蚜被寄生后也能进行远距离的飞行,在被寄生7日内,性母的飞行能力不受影响。本研究将为预测预报大豆蚜的发生和种群动态提供理论依据,也有助于评估寄生蜂在田间的扩散效果,为研究寄生蜂的越冬提供线索和理论依据,为有效的开展大豆蚜的生物防治具有重要的参考价值。更多还原

【Abstract】 The soybean aphid, Aphis glycines Matsumura, is a pest of soybean, Glycine max (L.). The soybean aphid reduces soybean yield directly via plant feeding and indirectly through virus transmission and reduction in seed protein content. High soybean aphid densities generally affect soybean plants by reducing plant height, pod number and total yield with yield reductions reaching 50%. The soybean aphid has recently invaded North America and Canada in 2000, where it is currently the most important insect pest of soybeans. Winged aphids (alates) engage in flight to colonize new plants, fields or habitats, and at critical times migrate between different host plants, aphids engage in (active) short-distance flight but also exploit weather patterns mainly for (passive) long-distance migration. Hymenopterous parasitoids are of great significance for natural control of aphid populations. The dispersal of parasitoids with host flight is tightly associated with host aphids. Aphid parasitoids take advantage of host flight for dispersal which would be contributed to biological control of the soybean aphid. In our research, we first studied the active flight potential of A. glycines under a range of environmental conditions and the trade-offs between flight and fecundity in the soybean aphid using an aphid flight mill to aid forecasting and management protocols for A. glycines at the landscape level, then we detected the host alates post-parasitization flight and the development of parasitoids in alate aphids. Our research has implications for classical biological control of the soybean aphid. The main results were summarized as follows.Aphids that were 12-24 h old exhibited the strongest flight behavior, with average flight durations of 3.3-4.1h, which represented flight distances of 4.6-5.1 km. After the age of 72 h, A. glycines flight performance rapidly declined. The optimum temperature range for flight was 16-28oC, while optimum relative humidity was 60%-90%. Our findings show that A. glycines posseses a fairly strong active flight aptitude (ability and inclination) and point to the possibility of flight initiation under a broad range of environmental conditions. Fecundity, longevity and reproductive periods of 12h old A. glycines alates which had engaged in >2.5 km long flights were significantly lower than those of <0.5 km individuals. The offspring of alates with flight experiences of >1.5 km also had lower fecundity than those produced by individuals which had engaged in flights <1.5km. Our results are therefore consistent both with direct trade-offs between flight and fecundity and a trade-off between flight and fecundity via maternal effects.Parasitism by A. varipes was allowed at different A. glycines developmental stages (i.e., alatoid 3th and 4th instar nymphs, alates) and subsequent aphid flight was measured using a computer-monitored flight mill. Only 35% of aphids parasitized as L3 alatoid nymphs produced normal winged adults compared to 100% of L4 alatoids. Flight performance of aphids that had been parasitized as 4th-instar alatoid nymphs 24 h or 48 h prior to testing was similar to that of un-parasitized alates of identical age. However, flight performance declined sharply for alates that had been parasitized as 4th-instar alatoid nymphs 72h and 96h prior to testing. Flight performance of aphids that had been parasitized as alate adults for 24h was not significantly different from un-parasitized alates of respective ages. Parasitoid larval and pupal development time and percent mummification did not differ between treatments in which aphids had flown over varying distances.We investigated the effect parasitism by the parasitoid Binodoxys communis on flight behavior of both the summer population soybean aphid and fall gynoparae. In summer population, flight distance of alate aphids that had been parasitized for 24 or 48 h did not differ significantly from unparasitized alates of the same ages. However, flight duration sharply declined for alates that had been parasitized for 72h and 96h. Larval and mummy development time, parasitoid emergence rate of passenger wasps did not differ between treatments in which the aphid host had flown over differing distances. In gynoparae, flight performance of gynoparae aphids that had been parasitized as 4th-instar alatoid nymphs 7d prior to testing was similar to that of un-parasitized alates of identical age.These results have the potential to aid forecasting and management protocols for A. glycines at the landscape level and help evaluating the dispersal efficiency and overwinter host of parasitoid. Our results have implications for natural biological control of A. glycines.更多还原