【作者】 庞淑婷；

【导师】 施祖华；

【作者基本信息】 浙江大学 ， 农业昆虫与害虫防治， 2010， 博士

【摘要】 烟粉虱Bemisia tabaci (Gennadius)属同翅目,粉虱科,是热带、亚热带及相邻温带地区的主要害虫之一。烟粉虱是一个复合种,种下包含许多生物型或隐蔽种,其中B型烟粉虱由于其对寄主适应性强,自20世纪90年代中后期侵入我国以来,迅速扩散,现已成为我国蔬菜、园林花卉等经济作物上的主要害虫。虽然选用抗虫品种是持续控制烟粉虱危害的有效措施之一,但是当其爆发危害时,还要采用如化学农药等应急措施进行防治。本文选择了11个番茄品种,研究了B型烟粉虱对它们的选择性及适生性差异,以及番茄品种对烟粉虱两种主要寄生蜂丽蚜小蜂Encarsia formosa浅黄恩蚜小蜂和Encarsia sophia的发育历期、寄生率和种间竞争的影响,并测定了在番茄常用商业品种上五种农药及其添加有机硅对烟粉虱各个龄期的杀伤效果和对丽蚜小蜂和浅黄恩蚜小蜂黑蛹及成蜂的毒力,以期为生产上选育稳定的番茄抗虫性状和有效利用天敌进行生物防治并且在烟粉虱大爆发时合理选择高效安全的农药提供理论依据。结果如下：1室内评价了B型烟粉虱对11个番茄品种(903,KT1,KT2,红椭圆,黄椭圆,202,203,207,809,红元帅1,巨红冠)的选择性及番茄品种对烟粉虱发育存活的影响。结果表明：B型烟粉虱成虫对11个番茄品种的取食和产卵选择具有一定差异,较偏好黄椭圆、KT1和202；中等喜好903、红椭圆和红元帅1；不喜好巨红冠、809、207和203。B型烟粉虱在11个番茄品种上的发育历期差异较小,从卵到成虫在KT1上所需时间最长,为21.35±0.55 d,在207上最短,为19.59±0.26 d。不同烟粉虱虫态在同一番茄品种上的存活率以1龄若虫较低,4龄+伪蛹期存活率较高。1龄若虫存活率在203上与巨红冠、红元帅1间存在显著差异；2龄、3龄和4龄+伪蛹在各供试品种上的存活率之间均没有显著差异；从卵到成虫的存活率,在203上的存活率最高,为83.50%；203与红椭圆、KT1、红元帅1、巨红冠、207、809间差异显著,其他品种之间差异不显著。2在5个烟粉虱喜好程度不同的番茄品种(黄椭圆,KT1,903,809,203)上,建立了实验种群生命表,并测定了番茄叶片的叶毛密度、pH值和主要营养物质含量。结果发现5个品种中,成虫平均寿命以黄椭圆上的最长,为19 d；903上的最短,为13.82 d；各品种上长短顺序依次为黄椭圆,KT1,809,203,903；平均单雌产卵量大小依次为黄椭圆,KT1,903,809,203；内禀增长率以在黄椭圆上的最高,为0.4706；在203上最低,为0.3435。综合来看,黄椭圆是B型烟粉虱的嗜好品种,最适合其生存和繁殖,也即抗虫性最弱。B型烟粉虱对203的选择性较弱,而且在203上的内禀增长率最低,表明203对于B型烟粉虱的繁殖适合性较低,对烟粉虱的抗虫性较强。而且在影响烟粉虱对寄主植物选择性的各个指标叶毛密度、pH值和营养物质含量中,黄椭圆都较为符合烟粉虱的选择要求。3比较研究了丽蚜小蜂E. formosa和浅黄恩蚜小蜂E. sophia在5个番茄品种上的发育历期和寄生率。结果表明：浅黄恩蚜小蜂的发育历期在各品种上都显著短于丽蚜小蜂。不同番茄品种对烟粉虱发育历期有一定的影响。丽蚜小蜂在5个品种上的发育时间由长到短依次为903,809,KT1,黄椭圆,203(15.95 d-14.59d),浅黄恩蚜小蜂在5个品种上的发育时间由长到短依次为903,黄椭圆,KT1,809,203(13.56d-12.00 d)。浅黄恩蚜小蜂在各个品种上的寄生率都低于丽蚜小蜂。丽蚜小蜂在5个品种上的寄生率由高到低依次为903、809、KT1、203、黄椭圆(65.00%-50.42%)；浅黄恩蚜小蜂在5个品种上的寄生率由高到低依次为809、203、KT1、903、黄椭圆(53.33%-35.83%)。4室内研究了烟粉虱两种寄生蜂的种间竞争及番茄品种对竞争结果的影响。结果发现：单独寄生时E. formosa的寄生数量普遍高于E. sophia;当烟粉虱供2种蜂寄生时(包括同时寄生和先后寄生),寄生总数和E.sophia单独寄生时相比稍有增加,和E. formosa单独寄生时相比并没有明显提高；E. formosa或E. sophia各自的寄生数分别比它们单独寄生时都明显降低。但是寄生蜂引起的烟粉虱总致死数却是供2种蜂寄生时比供1种蜂寄生时高。说明两种蜂存在种间竞争,这种竞争的结果虽然使各种寄生蜂的子代数减少,但不会影响防治效果,有时甚至还会增强控害效果,特别是在黄椭圆上,这种增强作用更为明显。在先后寄生中,第2头雌蜂可以通过取食寄主干扰第1头雌蜂的寄生,其中E. sophia取食致死作用比E. formosa强。不同的番茄品种对于两种寄生蜂的种间竞争有一定的影响,但影响不是很明显。5测定了五种药剂及其添加有机硅对烟粉虱成虫、若虫和卵的毒力。结果表明：不同药剂处理烟粉虱卵时,以蚊蝇醚和啶虫脒死亡率较高,啶虫脒添加有机硅后对卵的杀伤力具有增效作用。烟粉虱低龄若虫对药剂敏感性最高,各处理下死亡率均可达到92%以上,有机硅本身对低龄若虫杀伤作用较强。烟粉虱高龄若虫对药剂的敏感性比低龄若虫降低,有机硅对功夫和吡蚜酮毒性增效作用明显;有机硅本身对高龄若虫也有一定的杀伤作用。在成虫的生测中,以啶虫脒杀伤力最强,蚊蝇醚、吡蚜酮次之；有机硅对吡蚜酮增效作用明显。另外,蚊蝇醚可以通过渗透作用影响烟粉虱卵的孵化,极大地降低卵的孵化率。6评价了五种药剂及其添加有机硅对丽蚜小蜂和浅黄恩蚜小蜂黑蛹及成蜂的安全性。对丽蚜小蜂黑蛹的毒性以啶虫脒、功夫较高,吡蚜酮、蚊蝇醚较低；对丽蚜小蜂成蜂的毒性以啶虫脒和功夫最高,吡蚜酮最低。对浅黄恩蚜小蜂黑蛹的毒性以吡蚜酮、功夫较强,印楝素、蚊蝇醚较低；对浅黄恩蚜小蜂成蜂的毒性以啶虫脒和功夫较强,吡蚜酮和蚊蝇醚较低。印楝素中添加有机硅后对丽蚜小蜂黑蛹和浅黄恩蚜小蜂黑蛹毒性都明显增强,啶虫脒、功夫、吡蚜酮和蚊蝇醚添加有机硅后,对丽蚜小蜂黑蛹毒性都没有增强,对浅黄恩蚜小蜂黑蛹的毒性有一定增强作用。五种药剂添加有机硅后对丽蚜小蜂成蜂和浅黄恩蚜小蜂成蜂的毒性都没有明显增强作用。更多还原

【Abstract】 Bemisia tabaci Gennadius (Homoptera:Aleyrodidae) is one of the most serious pests in more than 90 countries and districts in tropical, subtropical regions and adjacent temperate zones. B. tabaci is a genetically diverse group that includes many morphologically indistinguishable populations differing in biological characteristics, but displaying clear geographic distributions called "biotypes". The B-biotype B. tabaci has spread quickly and has shown breakouts in many areas since it invaded China in the early 1990s. The B-biotype destroys crops by phloem feeding, excretion of honeydew, induction of phytotoxic disorders, and transmission of plant viruses. Recently, the B-biotype has become a serious pest to vegetables, ornamentals, and other economic crops in China and it is displacing other indigenous non B-biotype B. tabaci. Application of pest-resistant plant strains will be one of the efficient and sustainable ways for its control, but the chemical control measures still will be necessary, particularly when it breakout. In this thesis, we studied the selectivity and fitness of the pest to 11 tomato varieties, investigated the influences of the varieties on interspecific competition and biological characteristics of pest’s parasitoids, Encarsia formosa and Encarsia sophia, and evaluated virulence to B. tabaci and safety to the two parasitoids of pesticides and their mixtures with organosilicon in laboratory. The purposes of the studies are to provide scientific information for application of pest-resistant tomato varieties and natural enemies, and to the utilize pesticides reasonably and efficiently against this pest. The results of the experiments were summarized as follows:1 Bemisia tabaci’s selectivity to and influence of tomato varieties (Huangtuoyuan, KT1, KT2, Hongtuoyuan, Hongyuanshuai 1, Juhongguan,903,809, 207,203, and 202) on development and survival of the pest were investigated in laboratory. Bemisia tabaci exhibited significantly different selectivity to 11 tomato varieties. The preferred varieties were Huangtuoyuan, KT1 and 202, the less preferred ones were 903, Hongtuoyuan and Hongyuanshuai 1, and the rest fallen in the category of the least preferred varieties. The developmental duration from egg to adult varied from 21.35 days on KT1 to 19.59 days on 207. The lowest survival rate of B. tabaci nymph on the same tomato variety was the 1st instar, and the highest was the 4th instar. The survival rate in the 1st instar in variety 203 was significantly higher than those in varieties Juhongguan and Hongyuanshuai 1. The survival rate from egg to adult was highest in variety 203 (83.50%), significantly higher than those in varieties Hongtuoyuan, KT1, Hongyuanshuai 1, Juhongguan,207 and 809. However, no significant differences had been found in the survival rates for 2nd,3rd,4th and "prepupa" among the tested tomato varieties.2 Life tables of B. tabaci laboratory populations on 5 tomato varieties, for which the pest had different preference, were constructed, and leaf hair densities, pH value, contents of major nutrients of the 5 tomato varieties were also measured. The longevity of B. tabaci adults was the longest,19 days, resulted from variety Huangtuoyuan, followed in order by those from KT1,809, and 203, whereas it was the shortest from 903 (13.82 days). The average fecundity of B. tabaci adults on 5 tomato varieties was highest from Huangtuoyuan, followed in order by those from KT1,903,809,203. The intrinsic rate of increase (rm) of Huangtuoyuan, KT1,903, 809 and 203 were 0.4706,0.4289,0.4115,0.3974 and 0.3435, respectively. Experimental results, in generally speaking, suggested that B. tabaci was best adapted and showed the greatest preference for Huangtuoyuan and the lowest fitness on 203 oppositely. There were obviously differences in resistance to B-biotype B. tabaci among tomato varieties. The results of characteristics of plants that affect B. tabaci’s selectivity showed that Huangtuoyuan was satisfied to the selective requirement of B. tabaci.3 The development duration and parasite rate of two parasitoids, Encarsia formosa and Encarsia sophia, on 5 tomato varieties were compared. The results showed that development duration of E. sophia was significantly shorter than that of E. formosa on all 5 varieties. Tomato varieties could affect development duration of two parasitoids. The sequence of development duration of E. formosa on 5 tomato varieties from long to short was 903,809, KT1, Huangtuoyuan, and 203 (15.95 d-14.59 d), while the sequence for E. sophia was 903, Huangtuoyuan, KT1,809, and 203 (13.56 d-12.00 d). The sequence of parasite rate of E. formosa on 5 tomato varieties from high to low was 903,809, KT1,203, Huangtuoyuan (65.00%-50.42%); and the sequence of parasite rate of E. sophia on 5 tomato varieties from high to low was 809,203, KT1,903, Huangtuoyuan (53.33%-35.83%).4 The interspecific competition between two major parasitoids, E. formosa and E. sophia, and influence of tomato varieties on competition outcome were investigated in laboratory. E. formosa parasitized more B. tabaci than E. sophia did when presented alone on any of the tomato varieties investigated. When B. tabaci nymphs were exposed to both wasp species (either in combination simultaneous or one after the other), the number of B. tabaci nymphs parasitized by each individual wasp species, either E. formosa or E. sophia, was significantly decreased compared to when each wasp was presented on its own. The total mortality of B. tabaci was increased when B. tabaci nymphs were exposed to both wasp species compared to only one wasp species. Competition apparently occurred between E. formosa and E. sophia, which reduced parasitoid offspring numbers, but did not affect the biological control efficiency. Control efficiency even enhanced in some cases, particularly on variety HTY. When wasps parasitized one after the other, the second wasp could interfere with reproduction of the first through host feeding. This action was weaker in E. formosa than in E. sophia. The effect of different tomato varieties was not significant. Different tomato varieties had impact on the outcome of competition and biological control efficiency in a certain extent, however, the influence was not significantly.5 The toxicity of 5 insecticides and their mixtures with organosilicon on the adult, nymph and egg stages of B. tabaci were measured in laboratory. The results showed that Pyriproxyfen and Acetamiprid were effective to B. tabaci eggs. B. tabaci young nymphs were the most sensitive stage to insecticides; organosilicon itself also had virulence to young nymphs. B. tabaci old nymphs’sensitivity was lower than B. tabaci young nymphs; organosilicon also had virulence to old nymphs. Acetamiprid was the most effective pesticide to B. tabaci adults, followed by Pyriproxyfen, Pymetrozine. With organosilicon, toxicity of Acetamiprid to eggs, toxicity of almost 5 kinds insecticides to young nymphs, toxicity of Kungfu and Pymetrozine to old nymphs, toxicity of Pymetrozine to adults were significantly increased. Pyriproxyfen extremely reduced egg hatching rate through osmosis from the face to the back of leafs, extraordinary affect reproduction of B. tabaci.6 The safety of 5 insecticides and their mixtures with organosilicon on pupae and adults of E. formosa and E. sophia, two parasitoids of B. tabaci, were evaluated in laboratory. The highest toxic insecticides to E. formosa pupae were Acetamiprid and Kungfu, whereas the lowest were Pymetrozine and Pyriproxyfen. The high toxic insecticides to E. formosa adults were Acetamiprid and Kungfu, while the lowest toxic one was Pymetrozine in contrary. Pymetrozine and Kungfu were very toxic to E. sophia pupae, while Azadirachtin and Pyriproxyfen were much safer than them. Acetamiprid and Kungfu showed high toxicity to E. sophia adults, meanwhile Pymetrozine and Pyriproxyfen were low toxicity to E. sophia adults.The mixture with orgnicsilicon addition, toxicity of Azadirachtin to E. formosa pupae and E. sophia pupae were enhanced significantly. Toxicity of Acetamiprid, Kungfu, Pymetrozine and Pyriproxyfen with orgnicsilicon were not increased to E. formosa pupae, but increased slightly to E. sophia pupae. Orgnicsilicon didn’t get any tested pesticides toxicity up to E. formosa adults and E. sophia adults.更多还原