Experimental and theoretical study on the relationship between genetic diversity and system stability

本项目的主要目的是从实验和理论上研究遗传多样性与系统稳定性之间的关系。这是基于我们以前的研究结果，在实验的捕食系统组成的红豆象甲（Callosobruchus chinensis）和它的幼虫寄生蜂（Heterospilus prosoptera），系统与杂交株的红豆象甲可以共存寄生蜂显着长于系统与任何一个纯菌株。在此基础上，我们集中精力概括了遗传多样性对系统稳定性的重要性，并找到促进这种关系的机制。在我们的实验研究中，我们使用了两种豆象甲，Callosobruchus maculates和Obtectus，和三种寄生蜂，H. prosoptera，Anisopteromalus calcium和Dinarmus basalis。在豆象甲中，钝头豆象甲具有独特的特征 ...更多信息 因为它产卵时并不把卵附着在豆子的表面。这种特殊的产卵方法需要孵化的幼虫找到豆子并借用入口。有两种幼虫，一种（我们称之为先锋）主动借用豆上的入口孔，另一种（我们称之为追随者）使用先锋制造的入口孔。由于先驱者的初始死亡率相当高，孵化的幼虫最好是跟随者。因此，父母必须决定最佳比例的两种类型的幼虫，她的最高健身。同时，后代（卵子）必须有两种类型的最佳比例才能生存。因此，可能存在亲子冲突。在一个斑节蜱品系中，观察到两种不同品系的幼虫竞争策略（竞争和争夺）。通过对豆内幼虫行为的观察，发现攀援型竞争品系的幼虫在豆内构筑壁，限制了与其他幼虫的直接接触，最终允许多个幼虫羽化为成虫;而竞争型竞争品系的幼虫在豆内不构筑壁，最终相互接触，仅允许一个幼虫羽化为成虫。这表明，即使在一个品系的斑点拟步行虫中，竞争策略也可以是灵活的，并且可以根据它们所食用的豆类的质量（特别是大小）进行选择。少

The main purpose of the present project is to investigate experimentally and theoretically the relationship between genetic diversity and system stability. This is based on our previous findings that, in the experimental prey-predator system consisting of the azuki bean weevil (Callosobruchus chinensis) and its larval parasitic wasp (Heterospilus prosopidis), the system with the hybrid strain of the azuki bean weevil could coexist with parasitic wasps significantly longer than the system with either of the pure strains. Based on this finding, we concentrated our effort to generalize the importance of the genetic diversity on the system stability, and also to find the mechanisms promoting such relationships.In our experimental study, we employed two species of bean weevils, Callosobruchus maculates and Acanthoscelides obtectus, and three species of parasitic wasps, H.prosopidis, Anisopteromalus calandrae, and Dinarmus basalis. A.obtectus has a unique characteristics among the bean weevi … More ls, in that it lays eggs not attaching its eggs on the surface of the beans. This particular oviposition method necessitates the hatched larvae to find beans and borrow the entrance. There are two kinds of larvae, one (which we call pioneer) which actively borrow the entrance hole on the bean, and the other (which we call follower) which use the entrance hole made by pioneer. As the initial mortality of the pioneer is rather high, it is better for the hatched larvae to be a follower. Thus, the parent must decide the optimal proportion of the two types of larvae for her highest fitness. At the same time, offspring (eggs) must have some optimal proportion of the two types for their survival. Thus, there are possible parent-offspring conflicts. We carried out the experimental and theoretical studies for their optimal solution.In one strain of C.maculatus, we observed two strategies of larval competition (contest and scramble) in different lines. By careful observation of the larval behavior in the beans, we found that the larvae of the line with scramble type competition construct the wall in the bean, which restricted the direct contact with other larvae and eventually allowed multiple larvae emerge as adults, whereas, the larvae of the contest type competition constructed no wall, and eventually contacted each other in the bean, and only one larva could emerge as adult. This shows that even within one strain of C.maculatus, the competition strategy can be flexible, and can be selected for by the quality (especially size) of beans on which they feed. Less