温度及种子含水量对剪枝栎实象和青冈象卵发育的影响

Effect of temperature and seed water content on egg development of Mechoris ursulu and Curculio megadens

剪枝栎实象Mechoris ursulu和青冈象Curculio megadens是危害多种壳斗科植物坚果的重要害虫,在长期与寄主的相互作用中已进化出相应的反防御策略。了解两种象甲与植物间的相互关系,可有助于对其进行科学防治。本文通过温度等因子对具有相近生态位的剪枝栎实象和青冈象卵发育影响的比较研究,探讨产卵于寄主组织内的两种象甲卵期与植物防御的相互关系及青冈象的适应进化策略。结果显示,温度对剪枝栎实象和青冈象卵的发育历期有显著影响。在15~30℃内,两种象甲卵的发育历期逐渐缩短,发育速率加快;相同温度下青冈象卵的历期比剪枝栎实象长。温度对剪枝栎实象和青冈象卵的存活有显著影响。在15~25℃内,两种象甲卵的存活率逐渐增高;相同温度下剪枝栎实象卵的存活率高于青冈象卵的存活率。种子含水量对两种象甲卵的历期及存活率无显著影响,但相同含水量下剪枝栎实象卵的存活率高于青冈象卵的存活率。青冈象卵及卵室均明显小于剪枝栎实象,其卵的大小为0.0836 mm^(3),卵室为0.4650 mm^(3);剪枝栎实象卵的大小为0.2368 mm^(3),卵室为3.9589 mm^(3)。研究结果可为进一步探讨两种象甲与寄主植物的相互关系及青冈象的适应进化奠定理论基础。

Mechorhis ursulus and Curculio megadens are important pests of many plants nuts of Fagaceae and damage their nuts.They have evolved anti-defense strategies during long-term interaction with their hosts.It is basic for effectively controlling weevils to understand their relationship with the plants.We made the comparative study that temperature and other factors affected growth and development of eggs of M.ursulus and C.megadens which are similar ecological niche in order to discover the relationship between their eggs developmental period in host tissues and their hosts defense as well as the adaptive evolutionary strategies of C.megaden s.The results showed that temperature significantly affected egg developmental period of two weevils.In the range of 15~30℃,their egg development periods gradually reduced and was the shortest at 30℃and egg development rate speeded up and was the fastest at 30℃;and egg developmental period of C.megadens was longer than one of M.ursulus at the same temperature.Temperature also significantly affected egg survival rate of the two weevils.In the range of 15~25℃,egg survival rate of the two weevils increased gradually and egg survival rate of M.ursulus was higher than one of C.megaden at same temperature.Seed s water content did not significantly affect developmental period and survival rate of two weevils egg,and however the egg survival rate of M.ursulus was higher than one of C.megaden at the same water content.The egg and egg chamber of C.megaden were obviously smaller than ones of M.ursulus.The egg and egg chamber of C.megaden were 0.0836 mm^(3) and 0.4650 mm^(3),respectively,and those of M.ursulus were 0.2368 mm^(3) and 3.9589 mm^(3).The results could provide some theoretic implications for the further study of the relationship between the two weevils and their host plants and the adaptive evolution of C.megaden.