【作者】 罗其花；

【导师】 周婷；

【作者基本信息】 中国农业科学院 ， 特种经济动物饲养， 2011， 博士

【摘要】 热厉螨属(Tropilaelaps spp.)的蜂螨俗称小蜂螨,是亚洲地区重要的蜜蜂害螨。本研究调查了中国西方蜜蜂群内小蜂螨的自然种系构成,明确了我国小蜂螨的分类地位;在此基础上,进行了小蜂螨病流行病学调查,明确了我国小蜂螨的感染率、感染强度及其危险因素。针对流行病学中提出的危险因素,进一步开展了小蜂螨寄生生物学的研究,以此作为流行病学调查的有效补充,主要取得了以下结果:1.中国小蜂螨自然种系构成的研究:结合形态学初步鉴定结果,和mtDNA CO-Ⅰ基因,rDNA ITS1-5.8S-ITS2基因的序列综合分析结果,得出结论:寄生在中国西方蜜蜂群内的小蜂螨全部属于梅氏热厉螨(T. mercedesae),而并非早期定义的亮热厉螨(T. clareae)。在中国西方蜜蜂群内没有发现亮热历螨、柯氏热厉螨和泰氏热厉螨的寄生。2.梅氏热厉螨的流行病学调查:本次流行病学调查的反应变量是梅氏热厉螨感染率和感染强度,而自变量包括季节、气候、蜂种、地区、蜂群管理方式、蜂场规模和蜂农的养蜂年限和文化程度等。流行病学调查结果显示,梅氏热厉螨感染强度的危险因素包括地区、季节、大蜂螨协同感染和蜂群生产蜂王浆。梅氏热厉螨在秋季的感染率最高,其次是夏季,冬、春季节感染率较低;我国南方地区梅氏热厉螨的感染程度显著高于北方地区;狄斯瓦螨感染程度高的蜂群梅氏热厉螨感染程度往往也很高;如果蜂群生产王浆,其梅氏热厉螨感染程度通常也高。3.梅氏热厉螨和狄斯瓦螨的实验室饲养方法及同房繁殖生物学研究:本实验采用的是自然巢房接种法饲养,相对于ELISA板移虫饲养法,该法可重复性强,存活率高,可以得到大量子代蜂螨。两种螨的同房繁殖研究结果表明:梅氏热厉螨和狄斯瓦螨单独饲养时,其繁殖数量均高于混合饲养,表明两种螨同时存在对彼此繁殖能力都有显著的抑制或干扰作用。4.梅氏热厉螨与狄斯瓦螨封盖幼虫寄生率调查:研究结果表明两种螨同群寄生时其幼虫寄生率呈季节性波动,不同年份幼虫寄生率波动趋势也不同。狄斯瓦螨幼虫寄生率极显著高于梅氏热厉螨。5.梅氏热厉螨与狄斯瓦螨的成蜂寄率调查:两种螨同群寄生时其在成蜂上的藏匿部位不同;狄斯瓦螨的成蜂寄生率随季节和幼虫数量的波动而波动,但梅氏热厉螨基本上不选择成蜂寄生;在蜂子数量充足的条件下,两种螨均优先选择幼虫寄生;狄斯瓦螨的成蜂寄生率极显著高于梅氏热厉螨。6.梅氏热厉螨和狄斯瓦螨的危害水平及其对蜜蜂群势的影响:采用箱底残渣计数法对两种螨同群寄生时的危害水平进行调查,结果表明两种螨同群寄生时,狄斯瓦螨危害程度显著大于梅氏热厉螨,该结果与幼虫寄生率和成蜂寄生率的调查结果高度一致。在该感染水平下,蜂群连续2个月不治螨,群势差异不明显;但连续4个月不治螨,实验群群势明显下降;连续8个月不治螨,蜂群全部死亡,表明定期治螨工作在养蜂生产实践中的重要性。7.梅氏热厉螨中间寄主调查:我们对来自越冬保温物、蜂场田鼠和苍蝇上的小型寄生螨进行形态学和分子生物学的综合鉴定,结果表明它们均不属于热厉螨属的任何一种螨;小白鼠也不是梅氏热厉螨的中间寄主。梅氏热厉螨在我国北方地区的存在可能归因于转地蜂群的传播,但是也不排除还有其他潜在中间寄主的可能。本研究结果澄清了中国西方蜜蜂群内小蜂螨的分类学地位,提出了梅氏热厉螨感染率和感染强度的危险因子,初步探讨了梅氏热厉螨和狄斯瓦螨同群寄生时的寄生生物学特性,该结果将为梅氏热厉螨病的防治、蜂群的进出口检疫和防治决策的制定提供参考。更多还原

【Abstract】 Tropilaelaps mites are an economically important pest of honeybee throughout Asia. We have surveyed the species composition of the mites firstly. Based on this, we have a national epidemiological survey on the the infestation rates, intensity of the mites and its associated factors in Apis mellifera. According to the risk factors, as suggested by the epidemiological survey, some parasitologies of the mites were studied furtherly, as parasitologies were useful supplements for the epidemiological survey. The main results of the study are as follow:1. Study of species composition of Tropilaelaps mites: The morphology, mitochondrial DNA (mtDNA) CO-Ⅰand ribosomal ITS1-5.8S-ITS2 fragments of Tropilaelaps mites were surveyed for sequence variation or the presence or absence of specific restriction sites that differentiate four species of Tropilaelaps mite. Based on these identified diagnostic characters, all samples in this study corresponded to T. mercedesae, which has been mistaken for T. clareae until now. None of the other Tropilaelaps species were found infesting A. mellifera in China.2. Epidemiological survey on T. mercedesae in A. mellifera in China: The infestation rates, intensity of T. mercedesae and its associated factors such as climate, district, management practices, operation size,and beekeeper characteristics were included in the survey. The results showed that geographical location, season, royal jelly collection and Varroa infestation were the factors that influence the intensity of T. mercedesae. The highest infestation rate of T. mercedesae was encountered in autumn, followed by summer, and then spring and winter; the infestation rates and intensity of T. mercedesae in the central and south were higher than in the north; colonies with a high level of Varroa infestation or colonies that had be used for royal jelly collecting tended to show high levels of T. mercedesae.3. Methods of rearing Tropilaelaps mites and V. destructor to the adult stage in the laboratory and its reproductive biology. Newly sealed worker broods were inoculated with mites and cultured in the constant temperature incubator. In this method, high survival rates for both mites and hosts were seen, and numbers of daughter mites were harvested. Based on this, the reproductive biology of T. mercedesae and V. destructor were studied. The results showed that the numbers of offspring for both mites were reduced when they were raised by mixed-species pairs, indicating that there was an apparently mutual interference between V. destructor and T. mercedesae when they breeded in one cell.4.The infestation rates of V. destructor and T. mercedesae for sealed worker broods: The results showed that the infestation rates varied in different months and even in different years for both mites when they were co-infested in one colony, and the infestation rates of V. destructor was significantly higher than T. mercedesae.5. The parasitic features and infestation rates of V. destructor and T. mercedesae on adult worker bees: The results indicated that the hide place on adult worker bees for both mites was different when they were co-infested in one colony. The infestation rates of V. destructor varied with months and bee brood quantities, but adult bees were not prefered by T. mercedesae. The results also showed that if there were enough larve, both V. destructor and T. mercedesae prefer larve to adult bee, and the infestation rates of V. destructor on adlut workers were significantly higher than T. mercedesae.6. The colony’s infestation level of V. destructor and T. mercedesae and its effects on the population quantity of honey bee: The method of ’sticky board’was used in this study to inspect the infestation level of both V. destructor and T. mercedesae when they were co-infested in one colony. The results showed that the infestation levels of V. destructor were significantly higher than T. mercedesae, indicating that V. destructor was more dangerous to A. melllifera than T. mercedesae in the experimental condition,and the conclution was in line with the infestation rates for sealed worker broods and adult worker bee. The results also showed that the variation of population quantity of honey bee in the Apistan treated and untreated colonies was not obvious in the first two month, but a significant decline in the untreated colonies after 4 month, and all bees died in the untreated colonies after 8 month.7. Based on the morphological and molecular traits, the mites from house flies, field mousse and heat preservation materials were not Tropilaelaps mites, and white mouse is not an intermediate host of Tropilaelaps mites also.The results of the present study clarified the taxonomic status and biogeography of Tropilaelaps mites in China, provided factors that influence the infestation rates and intensity of T. mercedesae, and preliminarily revealed the biology characteristics of T. mercedesae and V. destructor when they were coinfested in one colony. These results should have implications for control and bee quarantine efforts in China.更多还原