秦岭山脉叶甲总科昆虫多样性的大尺度评估—基于宏基因组学方法

Qinling Mountain is unique geographical location and has a special ecological function. It is rich in biological resources and is known as the world famous natural ‘gene library’ of biological, which is a hot spot in biodiversity research in China. Coleoptera is the most biodiversity in organic sphere. Chrysomeloidea is the largest assemblages of beetles. All leaf beetles are phytophagous, closely related to plants, which is the ideal material for studying biodiversity. However, the research on the large-scale diversity assessment of insects from Qinling Mountain is lagging behind with simple research aim. In recent years, with the continuous development of sequencing technology, some new methods of biodiversity assessment have arisen. Among these new technologies, the large-scale biodiversity assessment based on metagenomic by high-throughput sequencing is the most popular and an effective method. In this study, we will select leaf beetles (Chrysomeloidea) which have the closest relationship with plants to established the mitochondrial genome reference library of leaf beetles (116 genera and 290 species) from Qinling Mountains by high-throughput sequencing. Based on metagenomics by high-throughput sequencing, the large-scale biodiversity assessment of leaf beetles from different sides and directions of Qinling Mountains was explored, which can reveal the species catalogue, species richness, distribution status, community structure and so on in Qinling Mountains,The relationship of genetic diversity, species diversity and ecological diversity were inferred too.

秦岭山脉地史古老、地理位置独特、生态功能特殊，承载着丰富的生物资源，被誉为世界著名的生物多样性天然“基因库”，是我国生物多样性研究的热点地区。昆虫纲鞘翅目是生物界生物多样性最丰富的类群，叶甲总科是鞘翅目最大类群之一，全部植食性，与植物关系密切，是研究生物多样性的理想材料。然而，目前秦岭生物多样性研究相对薄弱，研究目的单一。近年来随着测序技术的不断发展，新的评估方法不断出现，其中利用高通量测序基于线粒体宏基因组进行生物多样性大尺度评估表现出极大的优越性。本研究将选取与植物关系最为密切的叶甲总科昆虫为研究对象，利用高通量测序建立秦岭山脉叶甲总科116属290种的全线粒体基因组参考库，基于高通量测序数据对秦岭山脉不同坡向、不同走向的叶甲总科昆虫多样性进行大尺度评估，揭示秦岭山脉叶甲类昆虫的物种种类、丰富度、分布格局、群落结构；探究秦岭地区叶甲类昆虫遗传多样性、生物多样性和生态多样性三者的关系。

秦岭山脉地理位置独特、生态功能特殊，被誉为世界著名的生物多样性天然“基因库”，是我国生物多样性研究的热点地区，承载着丰富的生物资源，在物种、遗传和生态系统多样性3个层次上都具有国家乃至世界战略意义。然而秦岭昆虫大规模多样性评估的研究相对滞后，生物多样性的评估方法主要以传统评估为主，对生态物种的认识也是仅仅是描述型的，存在很大的生物多样性评估危机。本研究选取秦岭叶甲总科的昆虫为代表类群，利用高通量测序建立秦岭山脉叶甲总科线粒体基因组参考库，基于宏线粒体基因组对秦岭山脉叶甲总科昆虫多样性的大尺度评估。本研究取得了阶段性的进展：1）建立了较为全面的秦岭叶甲总科线粒体基因组参考库，共测得**新的线粒体基因组；2）基于秦岭叶甲线粒体基因组的数据，探究了叶甲总科高级阶元的系统关系，解决了叶甲科13个亚科之间的系统关系，明确了天牛科在叶甲总科的系统地位；3）以秦岭叶甲昆虫为例，结合世界其他地区的叶甲样本，探究了世界叶甲科多样性的分布格局，叶甲科在亚科级别分布具有地区性；4）基于4个大样方甲虫标本，利用分子生物学技术对秦岭甲虫进行大尺度评估，结果表明2个亚目、5个系、42个科、164个属、4657个OUTs，与传统的本地调查相比，发现了很多新的分类单元，分析结果还揭示秦岭南坡甲虫的多样性明显高于北坡。这些研究成果将叶甲总科的高级阶元系统关系的研究推向一个高度，揭示秦岭山脉甲虫的物种丰富度、分布状态、群落结构，为生物多样性保护和可持续利用提供了理论基础。