软枣猕猴桃野生种质的遗传多样性及果实品质的关联解析

Actinidia arguta is another cultivated species besides Actinidia chinensis, and the most widespread species within Actinidia genus with high frost hardiness and waterlogging resistance. Fruits of A. arguta display a hairless edible skin and a well-balanced sweet and a wide range of variation in flesh and skin color. The wild individual vines with excellent fruit flavor are easily founded. The wild populations of A.arguta in China are collected as experimental materials in the project. Genetic diversity of the species germplasm will be studied by genotyping with SSR markers. Ploidy variation of these samples will be identified. Spatial Pattern among/within the natural populations will be analysed for evaluating the diversity of A. arguta across China. In addition, diversity of fruit quality from those wild female vines is planning to be analysed for association analysis of fruit quality. Circumstantial and truthful scientific data and theoretical guidance are to be presented for conservation of wild A.arguta resources,which fills a vacancy in the field of scientific evaluation of the species resources in China.

软枣猕猴桃是除中华猕猴桃之外的另一个具有栽培价值的物种资源，也是猕猴桃属中自然分布最广的特色种，具有抗寒、耐涝等特点，果皮光滑无毛，果肉颜色变异丰富，风味极佳的野生单株颇为常见。本研究以我国软枣猕猴桃野生群体为研究对象，通过SSR标记研究该物种野生种质的遗传多样性，分析野生群体的倍性变异，进而研究该物种在居群内及居群间遗传变异的空间格局，评价我国软枣猕猴桃的遗传多样性基础信息；同时，收集并分析野生果实品质的变异，为选择优良群体样本开展果实品质的关联分析奠定基础。本研究将为猕猴桃野生资源保护提供详实的科学数据和理论依据，填补我国在软枣猕猴桃野生种质科学评价领域的空白。

本项目分别调查采集了东北长白山，陕西秦岭，四川广元曾家山、都江堰龙池、雅安天全二郎山、西昌螺髻山以及甘肃天水及陇南交界的小龙山（秦岭西段）、山东昆嵛山、湖北鹤峰、五峰、神农架等地共11个野生软枣猕猴桃居群样本256个野生个体，调查记录了居群分布生境，雌雄比例，果实形态性状等。 共开发出90对软枣猕猴桃SSR引物，这批引物能够在目前采集的所有软枣猕猴桃居群个体扩增，引物具有良好的多态性。用开发的SSR引物分析各居群的遗传多样性及遗传分化，发现各居群遗传多样性水平高，遗传距离与地理距离成正相关；秦岭地区居群具有最高的遗传多样性。倍性检测发现，大巴山居群倍性组成复杂，该群体中倍性变异从4-10倍体均存在，并首次在猕猴桃属/软枣猕猴桃物种中检测到10倍体；此次发现的软枣猕猴桃在东北以4倍体存在，但在华北，西南，华中等地，以4倍体为主，均以倍性复合体居群存在。