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41.
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记述小头叶蝉属Placidus Distant 3新种,即叉茎小头叶蝉P.furcatus sp.nov.,白斑小头叶蝉P.feu;omaculatus sp.nov.和龙王山小头叶蝉P.longwangshanensis sp.nov.. 相似文献
43.
记述叉突叶蝉属Balocerus Freytag & Morrison 1新种:双斑叉突叶蝉Balocerus bimaculatus sp.nov.。模式标本保存在贵州大学昆虫研究所。 相似文献
44.
同翅类昆虫的雄性生殖系统及精子发生(昆虫纲:半翅目) 总被引:3,自引:1,他引:2
本文比较了同翅类昆虫雄性生殖系统的结构、减数分裂期间染色体的行为和精子尾部的超微结构。研究表明蜡蝉总科和异翅类的精巢具有被膜,而蝉总科、叶蝉总科、沫蝉总科、角蝉总科、木虱总科、蚜总科、粉虱总科和蚧总科的精巢均不具有被膜。也可以根据精巢小叶的形状将精巢分为三类,蝉总科、叶蝉总科、沫蝉总科、角蝉总科、蚜总科和粉虱总科的精巢小叶为球形,蜡蝉总科、木虱总科和蚧总科的精巢小叶为管状,而异翅类的精巢小叶为片层状。减数分裂可以被分为5类:①蝉型(Cicadoidtype);②蜡蝉型(Fulgoroidtype);③木虱型(Psyloidtype);④蚜型(Aphidoidtype);⑤粉虱型(Aleyrodoidtype)和⑥蚧型(Coccoidtype),至少具有四个类群的减数分裂前期I具有弥散期,它们是:木虱总科、蜡蝉总科、蚧总科和异翅类。除粉虱总科和蚧总科的精子尾部退化以外,其余种类的精子鞭毛均具有典型的9 9 2轴丝结构。 相似文献
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46.
拟菱纹叶蝉属一新种记述(半翅目:叶蝉科:殃叶蝉亚科) 总被引:1,自引:0,他引:1
记述拟菱纹叶蝉属HishimonoidesIshihara1新种,即苗岭拟菱纹叶蝉Hishimonoidesmiaolingensis,sp.nov.。模式标本保存于贵州大学昆虫研究所。 相似文献
47.
中国柔突叶蝉属二新种记述(半翅目,叶蝉科) 总被引:1,自引:0,他引:1
记述柔突叶蝉属Abrus Dai et Zhang 2新种,即雷公山柔突叶蝉A.leigongshanensis sp.nov.和凹板柔突叶蝉Abrus concavelus sp.nov..新种模式标本保存于贵州大学昆虫研究所. 相似文献
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49.
Sébastien Boquel Marie‐Andrée Giguère Catherine Clark Upeksha Nanayakkara Jianhua Zhang Yvan Pelletier 《Entomologia Experimentalis et Applicata》2013,148(1):48-55
Seed potato crops are currently sprayed weekly with mineral oil to prevent transmission of the Potato virus Y (PVY; Potyviridae: Potyvirus), one of the most prevalent and important non‐persistent viruses affecting potato production. In spite of its wide usage as inhibitor of virus transmission, the mode of action for mineral oil is poorly known. The objective of this study was to quantify the effect of dosage and time from application of mineral oil on the inhibition of PVY acquisition. The bird cherry‐oat aphid, Rhopalosiphum padi (L.) (Hemiptera: Aphididae), known as vector of PVY, was used in all the experiments. The results indicated that mineral oil efficiently decreased PVY acquisition by 75 and 70% 1 day after application of 5 and 10 l ha?1, respectively. The inhibition effect decreased with time from application; mineral oil inhibits acquisition for less than 4 days at 5 l ha?1 and between 8 and 12 days at 10 l ha?1. As mineral oil was detected in the body of fewer aphids when they fed on plants 1 day after oil application, a change in the aphid probing behaviour on mineral oil‐treated plants was deduced. These results support the hypothesis that mineral oil physically inhibits the binding of the virus at the tip of the stylets. 相似文献
50.
Yannick Outreman Liliane Krespi Joan van Baaren 《Entomologia Experimentalis et Applicata》2013,147(2):167-174
Organisms can either evade winter's unfavourable conditions by migrating or diapausing, or endure them and maintain their activities. When it comes to foraging during winter, a period of scarce resources, there is strong selective pressure on resource exploitation strategy. Generalist parasitoids are particularly affected by this environmental constraint, as their fitness is deeply linked to the profitability of the available hosts. In this study, we considered a cereal aphid–parasitoid system and investigated (1) the host–parasitoid community structure, host availability, and parasitism rate in winter, (2) the influence of host quality in terms of species and instars on the fitness of the aphid parasitoid Aphidius rhopalosiphi De Stefani‐Perez (Hymenoptera: Braconidae: Aphidiinae), and (3) whether there is a detectable impact of host fidelity on parasitism success of this parasitoid species. Host density was low during winter and the aphid community consisted of the species Rhopalosiphum padi L. and Sitobion avenae Fabricius (both Hemiptera: Aphididae), both parasitized by A. rhopalosiphi at non‐negligible rates. Aphidius rhopalosiphi produced more offspring when parasitizing R. padi compared with S. avenae, whereas bigger offspring were produced when parasitizing S. avenae. Although aphid adults and old larvae were significantly larger hosts than young larvae, the latter resulted in higher emergence rates and larger parasitoids. No impact of host fidelity on emergence rates or offspring size was detected. This study provides some evidence that winter A. rhopalosiphi populations are able to take advantage of an array of host types that vary in profitability, indicating that host selectivity may drop under winter's unfavourable conditions. 相似文献