【作者】 郭萧；

【导师】 曹雅忠；

【作者基本信息】 中国农业科学院 ， 农业昆虫与害虫防治， 2010， 博士

【摘要】 采用生态学和生理学的试验方法对麦长管蚜Macrosiphum avenae (Fabricius)与不同小麦抗性品种互作关系和麦蚜翅型分化及飞行肌降解机制进行了研究。研究主要结果如下:(1)寄主对麦蚜种群及其生命参数的影响。抗性小麦能有效抑制麦蚜种群发展,刺激麦蚜有翅型的产生,减少麦蚜寿命,延长若蚜发育历期,降低成蚜繁殖力。此外,抗性寄主对害虫生理的影响可能有世代累加效应。EPG试验数据分析表明麦蚜取食活动受寄主影响较大,同时,从EPG数据还能得出生化抗性为主的抗性品种抗虫效果要优于以物理抗性为主的品种。通过对抗感小麦品种游离氨基酸分析,发现麦蚜种群数量与小麦游离氨基酸含量密切相关:有甘氨酸、缬氨酸等10种氨基酸与麦蚜种群密切相关,在这10种氨基酸中,以缬氨酸与麦蚜种群关系最为密切,其含量高低可以作为衡量小麦抗蚜性的指标之一。(2)麦蚜对寄主小麦的适应策略。田间系统调查表明:麦蚜种群对环境变化的有一定的适应性:当麦蚜迁入新的生境后,其飞行肌在几天之内降解,使麦蚜失去飞行能力,节约了大量能量,同时产下大量无翅蚜,种群在建立后1月之内达到高峰。寄主老化后,麦蚜有翅蚜明显增多,开始大量外迁,避免了因食物的匮乏而导致种群灭亡;同时田间定点观测表明:在抗性寄主上,因寄主的不适或其它抗生作用,可以促使麦蚜种群产生更多有翅蚜以逃离抗性寄主的危害。本研究还发现,随着寄主生育期的变化,麦蚜种群中红体色蚜在种群中的比例有所升高。(3)翅发育的形态和组织学特点。翅型分化发生在若蚜2龄时期,在此以前,无论有翅型还是无翅型均有翅原基组织,但2龄以后,一部分若蚜翅原基逐渐萎缩,直至消失,另外一部分若蚜翅原基得以继续发育,最终发育成翅。可见麦长管蚜翅型分化受母蚜生存环境的影响。(4)飞行肌降解机制研究。研究证实,飞行肌降解是由于肌细胞的凋亡引起,是麦蚜的主动生理反应。麦蚜在正常取食的条件下成蚜羽化后7日左右飞行肌细胞开始出现凋亡现象,9日后飞行肌开始出现可见的降解现象; 13日后,飞行肌降解完成。目前已经证实取食是诱导飞行肌降解的主要因素,抑制有翅成蚜的取食可以延迟飞行肌的降解,同时,麦蚜生殖活动也受到很大影响。更多还原

【Abstract】 Using ecological investigation methods and insect physiological technology, the wing development, degeneration and the mechanism of interaction between Macrosiphum avenae (Fabricius) and wheat are investigated. The main conclusions are as follow.(1) The effect of hosts on wheat aphid population paramaters. The resistant wheat varieties could inhibits effectively the development of aphid population, stimulate reproducing alate, decrease aphid’s longevity and fecundity, extend nymph developmental duration. In addition, the antibiosis to aphid has cumulative effects as aphid generations continue. The EPG datas showed that the wheat variety has greater effect on aphid feeding. The effect of biochemical resistance was better than the effect of physical resistance. There was close relationship between number of aphid population and free amino acid of wheat by analyzing the content of free amino acid. The correlation was significant between number of aphid population and other 10 amino acid such as glycine, valine et al. The correlation was most significant between valine and aphid population. The content of free valine in wheat suggests the one of evaluation index of wheat resistance.(2) Adaptive strategies of wheat aphid to wheats. Aphid population has certain adaptability to the changing environment. When alate aphid was allowed to settle down their host pants, their flight muscles began to break down within a few days. Flight muscle degeneration obliged aphid to decrease the number of flight and save much energy for fecundity. In new habitate, the aphid burns a plenty of apterous aphid. The number of aphid population peak stage when aphid colonized new habitate after a month. The aphid burns alate nymph in order to find new habitate when the host plants mature. The emergence of alate and emigration of aphid avoid the aphid population’s extinction for lacking food. The results show that feeding resistante wheat of aphid will burn more alate nymph to leave the host palnt. In the aphid population, the proportion of red bodycolor aphid increased with the growth stage of hosts..(3) Morphological and histological examination of aphid wing formation. The wing dimorphism took place in 2nd instar. Both the wing types have wing primordia before 2nd instar. The primordia gradually atrophy until complete disappearpance from 2nd instar to 4th instar in the wingless aphid. The primordia gradually develop into wing from 2nd instar to 4th instar in the alate aphid. The external factors had an effect on aphid wing formation. The wing formation is controlled by mother aphid living environment.(4) Mechanisms of histolysis in indirect flight muscles of alate aphid. The research results showed that the histolysis of flight muscles was induced by muscular cell apotosis. The muscular cell apotosis was an active physiological response of aphid. In mormal feeding condition, the cell of flight muscle began apotosis at 7-day adult. Flight muscle began atrophy at 9-day adult. The histolysis of flight muscle was complete at 13-day adult. Feeding was one of the main factors which has quiet an effect on the histolysis of flight muscle. When alate aphid was kept off the host pant after the final ecdysis, the breakdown of their flight muscles was prevented, and few larvipositions followed.更多还原