Studies on genetic structure of the beech forest and its conservation in the World Natural Heritage at Shirakami-sanchi

白上三地的大片地区保存着山毛榉森林，自1993年以来，该地区的中部（1697公顷）已被指定为世界自然遗产。为了深入了解这些森林在未来全球和当地气候变化可能出现时的表现，深入研究山毛榉森林的遗传结构以及单个树木应对环境变化的遗传能力是很重要的。本项目取得的成果可归纳为以下3个方面：1。不同类型的DNA标记，如通过分子分析MYB家族的SSR标记和IGS区域的片段拷贝，可以检测个体遗传成分的差异，已经被开发出来。为了开发一些母系遗传的DNA标记，对山毛榉叶绿体和线粒体DNA进行了克隆和测序。本研究在位于世界遗产缓冲区内的高村山（Takakuramori）约1.65公顷的土地上建立了一个调查样地，并对所有成年树和幼树的遗传标记进行了分析，以调查森林的遗传多样性和幼树的亲本关系。我们还调查了世界遗产中心地区、鹿儿岛县高沼山和茨城县小川遗址的山毛榉林，以查明这些森林的遗传距离，并对其遗传多样性进行比较分析。为了分析山毛榉单株的遗传能力，我们调查了山毛榉果实空壳的原因，发现山毛榉果实对异花授粉有很强的要求，自交不亲和可能是造成这一现象的原因。此外，为了鉴定出与环境适应有关的基因，并研究这些基因的遗传多样性，我们对山毛榉MYB基因家族进行了分析，迄今已鉴定出85个独立的基因。在这些基因中，我们发现了一些对各种环境胁迫有反应的基因，如寒冷、高温、干旱，还有一些基因的表达随季节波动很大。少

Beech forest is well conserved in a vast area of Shirakami-sanchi and the central part (1, 697 ha) of this area has been designated as the World Natural Heritage since 1993. In order to gain insights into how these forests would fare in the future when the global and the local climate changes might come forward, it is important to investigate intensively the genetic structure of the beech forest as well as the genetic capacity of the individual trees to cope with environmental changes. The achievements of this program have been summarized into the following 3 items.1. Different types of DNA markers, such as SSR markers through molecular analysis of MYB family and the fragmented copies of IGS region, allowing detection of differences in individual genetic components, have been developed. In an attempt to develop some maternally inherited DNA markers, the beech chloroplast and mitochondrial DNA has been cloned and sequenced.2. We established a plot for the inventory study in the area of … More about 1.65 ha at Mt. Takakuramori, which is localized in the buffering area of the World Heritage, and analyzed the genetic markers of all the adult trees and saplings to investigate the genetic diversity of the forest as well as parentage of the saplings. We have also investigated the beech forest at the central area of the World Heritage, at Mt. Takakuma Kagoshima prefecture, and at Ogawa site Ibaraki prefecture, to find out the genetic distances of these forests and to carry out the comparative analysis of their genetic diversities.3. In order to analyze the genetic capacity of individual beech trees, we investigated the cause for the beechnuts ending up empty, and found that there is a strong requirement for cross-pollination and self-incompatibility may be responsible for this. Furthermore, in order to identify some genes responsible for environmental adaptation and to investigate the genetic diversity of these genes, we analyzed the beech MYB gene family and identified, so far, 85 independent genes. Among these genes, we found out some genes responsive to various environmental stresses, such as, cold, high temperature, drought and also some genes whose expression fluctuates extensively depending on the seasons. Less