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经过冬蜜花期对以湖北鄂西中蜂为母本、广东粤东地中蜂为父本的杂交一代与本地中蜂进行比较,结果表明:杂交一代的繁殖力和产蜜量分别比本地中蜂高4.4%和11%。夏季乌桕花期对回交代进行对比结果表明:其繁殖力和产蜜量分别比本地中蜂高6%和21%。  相似文献   
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Summary The genus Striga contains some of the most noxious parasitic plants, which have a devastating impact on cereal production in Africa; of most importance are Striga hermonthica and Striga asiatica . Complete resistance to infection by Striga species does not exist in cultivated cereals. Of great interest is the possibility that wild relatives of cereals may provide a genetic basis for resistance or tolerance to infection and may be of enormous value for the development of resistant crops. A wild relative of cultivated sorghum, Sorghum arundinaceum , demonstrated tolerance to infection by S. asiatica , with little impact of S. asiatica on host growth or grain production compared with the detrimental impact of the parasite on cultivated sorghum. Infection by S.hermonthica , however, had a significant influence on host performance for both wild and cultivated sorghum. Differences in host:parasite responses may be explained by the timing of parasite attachment and differences in host specificity for these two Striga species.  相似文献   
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Orobanche ramosa is a parasitic Angiosperm responsible for severe yield losses in several economical crops. It is a serious threat in oilseed rape in France and Morocco and is appearing in carrot crops in Morocco. In this study, several varieties of oilseed rape and carrot were screened in order to identify resistant cultivars and to characterize the resistance mechanisms involved. All the 15 oilseed rape varieties tested were susceptible. In carrot, the varieties 'Colmar à coeur rouge' and 'Nantaise demi-longue' were susceptible, whereas 'Palaiseau' and 'Buror' were resistant. In the susceptible 'Colmar à coeur rouge' carrot no defence reactions were found and the development of the parasite inhibited carrot tap root formation. In the resistant carrot varieties, the parasite germinated, became attached to the host root but became necrotic before emergence. In 'Buror' carrot, formation of a mechanical barrier was associated with the restriction to the cortex of the parasite. In maize cv. 'Vigni', a non-host of O. ramosa, thickening of xylem vessels, cell divisions in the central cylinder and formation of an encapsulation layer were observed in association with restricted development of Orobanche haustoria.  相似文献   
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草地贪夜蛾Spodoptera frugiperda(J.E.Smith)是原产于美洲热带和亚热带地区的重大农业害虫,具有迁飞快、寄主广、繁殖强、为害重、适生力强等特点。自2019年初入侵我国以来,现已蔓延到我国21个省(市、自治区),草地贪夜蛾将在我国定殖并呈现周年常态化发生态势,对我国玉米产业的发展构成严重威胁。本文综述了草地贪夜蛾的国内外寄生性和捕食性天敌昆虫及其应用情况,并就我国天敌昆虫产业发展的现状和存在的问题提出了建议,以期为应用天敌昆虫防控草地贪夜蛾提供参考。  相似文献   
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星天牛Anoplophora chinensis Forster为亚洲本土的林木钻蛀性害虫,近年来已入侵到一些欧洲国家,被列为重要的国际检疫对象。本文综述了国内外有关星天牛的自然天敌种类及其人工利用的研究进展。我国古代曾用黄猄蚁Oecophylla smaragdina Fabricius防治危害柑橘树的星天牛,近年来开展了野外释放天敌昆虫花绒寄甲Dastarcus helophoroides Fairmaire成虫和卵卡防治星天牛的实践,都取得了较好的防治效果。川硬皮肿腿蜂Sclerodermus sichuanensis Xiao对星天牛低龄幼虫具有一定的控制作用,天牛卵长尾啮小蜂Aprostocetus fukutai Miwa&Sonan显示出了良好的生物防治利用前景,在意大利对星天牛的卵寄生率最高达72%。一些欧洲本地拟寄生蜂种类,如柄腹茧蜂Spathius erythrocephalus Wesmael也可寄生入侵当地的星天牛自然种群。此外,利用昆虫病原微生物控制星天牛,也具有较好的防治前景,如用布氏白僵菌Beauveria brongniartii Petch制成的无纺布菌条已经在日本开发成为一种商品,真菌侵染可引起天牛高致死率。昆虫病原线虫夜蛾斯氏线虫Steinernema feltiae Filipjev和小卷蛾斯氏线虫S.carpocapsae Weiser也具有作为生物杀虫剂用于控制星天牛幼虫的开发前景。本文还讨论了目前星天牛生物防治中存在的不足及其原因,展望了今后研究的重点和方向。  相似文献   
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日本细毛环腹瘿蜂Leptopilina japonica是斑翅果蝇Drosophila suzukii的优势寄生性天敌之一, 对斑翅果蝇具有良好的生防潜力。为更好地利用日本细毛环腹瘿蜂防控斑翅果蝇, 本研究在室内观察了日本细毛环腹瘿蜂的行为活动和生长发育特征。采用室内接虫法研究了该蜂对斑翅果蝇2龄幼虫的寄生能力。分别运用Holling Ⅱ型圆盘方程、搜寻效应方程和Hassell-Varley模型拟合分析了日本细毛环腹瘿蜂的寄生功能反应、搜寻效应和自身密度干扰效应。结果表明:日本细毛环腹瘿蜂的寄生功能反应符合Holling Ⅱ模型, 其拟合方程为:Na=0.70N/(1+0.03N); 寄生效能(a/Th)为15.78; 在一定空间内, 寄生蜂的寄生量随寄主密度增加而增大, 至寄主密度达25头/罐后寄生量趋于平稳; 寄生蜂的搜寻效应随着寄主密度的增加而减弱; 当斑翅果蝇的密度分别为10、20、30头/罐时寄生蜂自身密度干扰模型分别为E10=0.487 8P-0.871 3; E20=0.442 0P-0.676 8和E30=0.346 2P-0.433 7, 在同一寄主密度下, 日本细毛环腹瘿蜂的寻找效应均随自身密度的增加而减弱。日本细毛环腹瘿蜂对斑翅果蝇2龄幼虫具有较好的寄生效能, 但寄主密度较大会导致日本细毛环腹瘿蜂的寄生效能减弱, 随着寄生蜂自身密度的增加, 其种内个体间会出现干扰作用。  相似文献   
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Varroa destructor (Mesostigmata: Varroidae) is arguably the most damaging parasitic mite that attacks honey bees worldwide. Since its initial host switch from the Asian honey bee (Apis cerana) (Hymenoptera: Apidae) to the Western honey bee (Apis mellifera) (Hymenoptera: Apidae), Varroa has become a widely successful invasive species, attacking honey bees on almost every continent where apiculture is practiced. Two haplotypes of V. destructor (Japanese and Korean) parasitize A. mellifera, both of which vector various honey bee-associated viruses. As the population of Varroa grows within a colony in the spring and summer, so do the levels of viral infections. Not surprisingly, high Varroa parasitization impacts bees at the individual level, causing bees to exhibit lower weight, decreased learning capacity, and shorter lifespan. High levels of Varroa infestation can lead to colony-wide varroosis and eventually colony death, especially when no control measures are taken against the mites. Varroa has become a successful parasite of A. mellifera because of its ability to reproduce within both drone cells and worker cells, which allows populations to expand rapidly. Varroa uses several chemical cues to complete its life cycle, many of which remain understudied and should be further explored. Given the growing reports of pesticide resistance by Varroa in several countries, a better understanding of the mite’s basic biology is needed to find alternative pest management strategies. This review focuses on the genetics, behavior, and chemical ecology of V. destructor within A. mellifera colonies, and points to areas of research that should be exploited to better control this pervasive honey bee enemy.  相似文献   
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草地贪夜蛾Spodoptera frugiperda(J.E.Smith)原产于美洲,自2019年初入侵我国以来迅速向北蔓延,对农业造成了巨大损失。其寄生蜂作为重要的天敌资源之一,在害虫防治中具有不可替代的作用。本文对目前已鉴定到的9个科170种草地贪夜蛾寄生蜂天敌等进行了分类总结,而后讨论了其在害虫生物防治方面的应用前景,并围绕草地贪夜蛾寄生蜂寄生因子调控寄主免疫反应的分子机理展开详细论述。该研究旨在丰富草地贪夜蛾的生物防治资源素材,并为该害虫的绿色防控提供重要的理论与实践指导意义。  相似文献   
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