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91.
苏晓群 《陕西师范大学学报(自然科学版)》1991,(2)
通过对寄生乌鳢肠道及幽门盲囊的广东艾美虫的研究,揭示了寄主以及季节变化对此虫感染情况的影响作用,指出广东艾美虫感染率的最高值出现在寄主体长20~24.9cm中,且雄性寄主较雌性寄主更高。另从气候的季节变化规律分析,感染率春季最高,而感染强度秋冬季最高。 相似文献
92.
Adult morphology ofTrichogramma is modified by environmental conditions during the preimaginal development. For instance, the low temperatures inducing diapause cause a decrease of the ratio length of longest seta on male flagellum/width of flagellum inT. evanescens. The species of the host also influences numerous body ratios. So, in females, the development of tibiae with regard to wings is more important withScotia ipsilon than withGalleria mellonella. These results confirm the necessity of performing comparative morphological studies on individuals reared in the same conditions. 相似文献
93.
R. Nishida T. Ohsugi S. Kokubo H. Fukami 《Cellular and molecular life sciences : CMLS》1987,43(3):342-344
Summary A methanolic extract ofCitrus unshiu induces oviposition by females of aCitrus-feeding swallowtail butterfly,Papilio xuthus L. The chemical factors responsible for stimulating oviposition were isolated and characterized as 5-hydroxy-N-methyltryptamine, adenosine, vicenin-2, narirutin, hesperidin and rutin. An artificial blend of these six components elicited significant oviposition behavior, apparently identical to that induced by contact with intactCitrus leaves. 相似文献
94.
《Journal of Natural History》2012,46(3):643-712
Based on a cladistic analysis, the subfamily Rhinocolinae is redefined to comprise 13 genera and 39 species, of which two genera and eight species remain unnamed. Four new genera and 14 new species are described; one subfamily and one genus are synonymized, and two species are recombined; one lectotype is designated. The subfamily is divided into two groups, one with a Gondwanan distribution comprising four genera in Australia, New Zealand, South America and Africa, and another with Laurasian distribution in the Palaeotropics, the Western Palaerctic and North America comprising nine genera. Twenty-one species develop on host plants in the Rutales, three on Asteraceae, three on Cistaceae and one on Zygophyllaceae. The genus Pistacia (Anacardiaceae) in particular hosts six species whose biology is discussed. 相似文献
95.
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97.
《Journal of Natural History》2012,46(13-14):1079-1093
Theoretically, Lepidoptera should be able to adapt to using annuals as larval host plants through increased development rates and migration capacity. Even so, we show that annuals are used less frequently as host plants than expected among British and continental European butterflies. In particular, no example has been found of a European butterfly monophagous on an annual plant over its entire range. Use of annuals is proportionately greater among species that exploit increasing numbers of host plants and among subsidiary host plants than among primary (main) host plants. Annuals as host plants change status as habitat components with changes in species' spatial dynamics. The statistical findings point to perennials as providing host plant refuges, whereas the few case examples of site monophagy suggest that annuals can become valuable complementary resources during range extensions such as those currently associated with climatic warming. Annuals are more likely to be used in highly restricted circumstances, when environmental conditions allow the plants to persist over prolonged periods (i.e. when they are behaving like biennials) or when their spatial predictability is high because of low seed dispersal. 相似文献
98.
《Journal of Natural History》2012,46(45-46):2815-2840
The species Monoeca haemorrhoidalis, the largest species in the genus, occurs in the Atlantic rainforest of southeastern and southern Brazil. The aim of this study was to investigate the nesting ecology of M. haemorrhoidalis and its interactions with natural enemies. Nest aggregations were studied in an area at the transition between Dense and Mixed Temperate Rainforest, south Brazil. The period of nest construction and cell provisioning started in October and stopped in February. Plant species of the families Orchidaceae, Styracaceae and, mainly, Malpighiaceae, were the most important pollen and floral oil resources that were used in brood cell provisioning. During the nest construction activities, 27 insect species were observed at the nesting sites. The cleptoparasitic bee Protosiris gigas was one of the main causes of M. haemorrhoidalis mortality. Some behavioural and biological data of P. gigas are also reported. 相似文献
99.
研究桔小实蝇成虫对桔、橙等9种水果的嗜好性。结果表明,桔小实蝇主要在上午9~10时取食,最嗜食的寄主是桔、橙,其次为石榴、芒果,最不嗜食的寄主是香蕉。试验进行了乐斯本等9种杀虫剂对桔小实蝇成虫的毒力测定,丁硫克百威的杀虫活性最高,其次为乐斯本,氯氰菊酯、联苯菊酯、敌百虫也具有较高的毒杀效果。 相似文献
100.
高校学生社团是由高校学生依据兴趣爱好自愿组织、按照一定章程自主开展活动的学生团体,它是实施素质教育的重要途径。在非正式群体视域下研究大学生社团,有利于大学生社团的有效管理和满足大学生自身发展的需要。本文通过对青海大学大学生社团建设和社团活动状况的调查,分析大学生社团建设中存在的主要问题,提出在非正式群体视域下完善大学生社团建设的对策建议。 相似文献