农药亚致死剂量对优姬蜂交配行为影响的研究

用１００×１０－６％农梦特和空白农梦特乳油，以及０．０１×１Ｏ－６％氯氰菊酯处理寄生于小菜蛾幼虫的优姬蜂雄蜂，观察农药亚致死剂量对优姬蜂交配行为的影响。结果表明，受农梦特处理的雄蜂只有６８．１８％在遇到雌蜂时引起翅膀扇动。在农梦特和氯氰菊酯处理中，雄蜂对雌蜂在交配行为上的反应迟钝，它们从试验开始到扇动翅膀的时间显著地比对照和空白农梦特乳油的推迟，其交配率分别为２７．２７％和５５％，交配抑制率分别为５３．６８％和３２．０６％。

盲蝽交配行为研究进展

交配对昆虫的繁衍至关重要,决定了昆虫种群的发展趋势。半翅目盲蝽科昆虫具有繁殖快,产卵量大,世代重叠严重等特点,使其容易暴发难以防控,严重影响了农业的生产和发展。本文针对盲蝽的交配行为进行综述,系统阐明了盲蝽科不同物种间交配特征、交配高峰、交配节律以及交配次数的差异,并对盲蝽科昆虫存在的多次交配行为和交配后抑制现象及机理进行了简要介绍,论述了抑性欲素对盲蝽科昆虫交配后行为的调控。通过以上论述,为针对盲蝽交配行为开发新型交配干扰剂并用于盲蝽的综合防治提供理论依据。

昆虫雄性生殖腺分泌物的功能

昆虫两性成功交配后,雄性生殖腺分泌物使雌性昆虫的生理和行为都发生了巨大的改变。昆虫雄性生殖腺分泌物含有多种具有生物活性的分子,这些生物活性分子通过成功交配转移到雌虫生殖道后,对雌虫的生殖活动产生影响,使交配雌虫一段时间内不再交配,使已转移的精子易于在雌虫生殖道内储藏,使卵与精子完成受精过程,还可刺激雌虫产卵和卵的发育,调控排卵和产卵等生殖过程。在精子的转移过程中,雄性生殖腺分泌物中的抗菌媒介质能使雌虫的生殖导管提供友好的环境。此外,一些昆虫的雄性生殖腺分泌物还含有一些有毒的化学物质,保护已产下的卵不被天敌取食和病原体侵染。

A de novo originated gene depresses budding yeast mating pathway and is repressed by the protein encoded by its antisense strand

Recent transcription profiling studies have revealed an unexpectedly large proportion of antisense transcripts in eukaryotic genomes. These antisense genes seem to regulate gene expression by interacting with sense genes. Previ- ous studies have focused on the non-coding antisense genes, but the possible regulatory role of the antisense protein is poorly understood. In this study, we found that a protein encoded by the antisense gene ADF1 acts as a transcription suppressor, regulating the expression of sense gene MDF1 in Saccharomyces cerevisiae. Based on the evolutionary, ge- netic, cytological and biochemical evidence, we show that the protein-coding sense gene MDF1 most likely originated de novo from a previously non-coding sequence and can significantly suppress the mating efficiency of baker＇s yeast in rich medium by binding MATa2 and thus promote vegetative growth. These results shed new light on several im- portant issues, including a new sense-antisense interaction mechanism, the de novo origination of a functional gene, and the regulation of yeast mating pathway.