镉污染对稻田蜘蛛优势种发育与繁殖的影响及其机理

通过重金属镉在蜘蛛体内生物富集效应的测定，考察雌蛛卵巢发育程度、卵巢合成卵黄蛋白能力及卵黄蛋白理化特性的差异，探讨镉对蜘蛛繁殖力的影响；比较雌、雄成蛛交配行为，雌成蛛产卵率和产卵袋数、产卵量和孵化率、雌蛛护卵和护幼行为的差异，揭示镉对蜘蛛繁殖的影响；系统地考察蜘蛛的胚胎早期、体节期、胚胎逆转期和幼虫期4个发育阶段的形态特征和发育过程，并定量的分析镉对蜘蛛胚胎发育的影响；比较幼蛛发育历期的长短、成活率的高低及蜕皮次数的差异，揭示镉对蜘蛛胚后发育的影响。利用PCR技术克隆卵黄蛋白基因并进行测序，同时结合Northern blot、Western blot等技术阐明卵黄蛋白基因是否在镉胁迫下发生突变以及在胚胎发育过程中的时空表达模式差异，进而在分子水平上揭示镉污染对蜘蛛生长、发育和繁殖影响的机理。理论上在胚胎学和保护学等方面丰富蜘蛛学内涵；实践中为保持农田蜘蛛物种的稳定性及镉污染治理提供新依据。

With rapid industrial development and urbanization, heavy metal contamination becomes a serious problem worldwide. The aim of this study was to investigate the potential effect of heavy metal cadmium (Cd) on reproductive behavior and physiology of two dominant spider species, Pardosa pseudoannulata and Coleosoma octomaculata between Cd contaminated and uncontaminated rice fields. First, we will collect the spiders from Cd uncontaminated and contaminated fields, quantify the Cd levels at different developmental spider stages, and examine the potential effect of Cd on mating behavior, egg production rate, egg hatching rate, and egg and larva protection behavior of female. Then, we will investigate the potential effect of Cd on post embryonic development of spiders by examining the potential Cd effect in larval developmental duration, mortality and molting times. Finally we propose to clone and sequence vitellogenin genes from the spiders using RT-PCR in combination with Northern blot and Western blot techniques to reveal whether Cd accumulation in spiders could affect vitellogenin expression profiles, resulting in alternation of reproductive physiology. The results from the proposed study will provide useful information for understanding the effects of Cd accumulation on the growth, development and reproduction of spiders and lay solid foundation for developing strategies for spider protection and Cd contamination control in ag-ecosystem.