海南岛油茶资源分类鉴定与评价

Tea-oil Camellia which are belonged to the genus Camellia L., Theaceae, is a general name for some economic plants with high oil content in seeds. It is a key woody edible oil tree in China. Hainan Island is the southernmost distribution for tea-oil Camellia resources in China. Due to the rich and specificity of tea-oil Camellia resources, the superior natural conditions for the growth of tea-oil Camellia , and the strong trend of development for Camellia oleiferaindustry in Hainan Island, Study and utilization on tea-oil Camellia resources of Hainan Island have attracted much attention in recent years. However, the systematic evaluation of the tea-oil Camellia resources of Hainan Island has not been studied at home and abroad. The taxonomic problem of tea-oil Camellia resources is still unclear, which is extremely unfavorable for innovative utilization and industrial development in tea-oil Camellia resources of Hainan Island..In this project, there are studies on the phenotype, karyotype structure, cpDNA and nrDNA fragment sequence and SRAP marker polymorphism for tea-oil Camellia resources from different area in Hainan Island, which for being evaluated the diversity of this resources systematically; and the tea-oil Camellia resources from different area in Hainan Island will be identified taxonomically by comparing morphology, cell taxonomy and molecular taxonomy. The results will be explained to the diversity and specificity of tea-oil Camellia resources of Hainan Island systematically, and solved the classification problem of tea-oil Camellia resources in Hainan Island. So the results in this project can provide a scientific basis and reference to the protection and utilization of tea-oil Camellia resources of Hainan Island, and promote the development of the tea-oil Camellia industry in Hainan. All findings will enrich the data of taxonomic classification of Sect. Oleifera in Camellia.

油茶为山茶科(Theaceae)山茶属(Camellia)中种子油脂含量较高且具有经济栽培价值的植物总称，是中国重要的木本食用油料树种。海南岛为中国油茶资源分布的最南缘。近年由于海南岛丰富而特色的油茶资源、良好的水热条件和产业发展势头，海南油茶资源研究与开发利用备受关注。但是国内外对该资源的系统评价尚未开展，关于资源分类问题仍无定论，这对资源创新利用与产业发展极为不利。本项目拟从表型、核型、cpDNA和nrDNA片段序列、SRAP标记多态性等方面对海南岛油茶资源进行系统评价；并通过比较形态学、细胞分类学、分子分类学三个方面数据的综合研究和系统比较，对海南岛油茶资源进行分类鉴定，建立DNA条形码。其结果将系统阐述海南岛油茶资源的多样性和特异性，解决海南岛油茶资源的分类问题，为海南岛油茶资源保护与创新利用，海南省特色油茶产业发展提供科学依据，同时也丰富山茶属油茶组系统分类方面的资料

海南岛为中国油茶资源分布的最南缘，本项目从表型、倍性、分子等多方面对海南岛油茶资源进行系统评价和分类鉴定。结果表明：（1）海南岛油茶资源的叶片、花与果实表型多样性丰富，海南油茶资源叶柄、嫩枝和花萼均被毛，叶柄与嫩枝被毛情况受生境影响大，花和叶表型不宜做为海南岛油茶资源分类鉴定主要依据，但其果形更近接于越南油茶。（2）基因型差异对海南油茶花粉萌发率和花粉管伸长影响显著。（3）海南岛油茶资源倍性丰富，其中六倍体、八倍体和九倍体类型居多，倍性不能做分类鉴定海南油茶资源的主要依据。（4）海南岛油茶籽平均种仁含油率为49.13%；茶籽油无机元素含量丰富，不饱和脂肪酸含量在90%左右，角鲨烯等活性成分含量高。（5）在海南和两广地区越南油茶种仁中共鉴定出1057种代谢产物，其中76种和99种代谢产物分别被注释为中药关键活性成分和活性药物成分；海南和两广地区越南油茶种仁存在不同代谢组学特征，检测到了22种代谢产物可作为鉴定海南和两广地区原产越南油茶的潜在指标物质。（6）共测序组装注释了8个油茶组油茶物种种质的叶绿体基因组，其中小果油茶叶绿体基因组与其他供试基因组的差异最大，在8个基因组间基因ycf1变异位点最多，获得56对多态性标记引物，以及不同物种间和海南油茶与内地油茶间的特异DNA标记。（7）油茶组不同油茶物种居群遗传多样性低，居群间遗传分化显著；分析结果支持小果油茶为一个独立物种，命名为Camellia meiocarpa；支持高州油茶、越南油茶和陆川油茶归并为同一物种，统称越南油茶（C. drupifera），海南油茶是越南油茶的特殊生态类型或变种；初步分析认为，普通油茶可能由越南油茶和小果油茶杂交进化而来。（8）中国越南油茶种质资源遗传多样性低，居群分化显著，分析认为地理隔离、海岛效应在引起遗传分化大的谱系结构的同时，也降低了越南油茶的遗传多样性。. 本项目的研究结果对海南岛油茶资源创新利用奠定良好基础，同时也补充了山茶属物种分类信息。