基于EST-SSR标记的平欧杂种榛品种鉴定

为建立准确、高效的平欧杂种榛品种鉴定方法,本研究收集目前国内普遍引种的平欧杂种榛品种(品系)43个,选用课题组已开发的12对EST-SSR引物进行品种鉴定方法研究。结果表明:不同引物在供试样品中的PIC值为0.3800~0.7839,平均为0.5113,各引物组合经毛细管电泳均显示出了良好的扩增效果;平欧杂种榛品种(品系)间的亲缘关系较为复杂,其中薄壳红和平欧62、平欧3和平欧7、平欧30和平欧48的遗传距离最近;引物CAF-2、CAF-3、CAF-12和CAF-13组合使用,可完全区分43个平欧杂种榛品种(品系),其中引物CAF-2与CAF-13组合使用,可鉴定16个主栽品种(品系)。上述研究结果为平欧杂种榛的品种鉴定提供了便捷、有效的方法,也可为其他榛属植物研究提供参考。

Cultivar Identification of Ping'ou Hybrid Hazelnut Based on EST-SSR Markers

Hazelnut(Corylus L.)is one of the most important nut crops and woody oil plants in the world.It is commonly thought there are eight hazelnut species and two varieties distributed in China.Ping'ou hybrid hazelnut (C.heterophylla Fisch.× C.avellana L.),which is hybrid of Ping hazelnut(C.heterophylla Fisch.)from northeast China and the seedlings of European hazelnut(C.avellana L.)introduced from Italy in 1980's,shows characters of big nut,high yield,high kernel percentage and well-adapted in most area in China.Dozens of cultivars and varieties of Ping'ou hybrid hazelnuts are selected based on the comparative trials and regional trials,among which sixteen are the main cultivars.Until now,Ping'ou hybrid hazelnuts have been widely cultivated in twenty provinces of China since 2000 with the cultivated area more than 60000 hectare.As for breeding and resources assessment,the genetic background of those cuhivars and varieties is very complicated due to the mixed pollen of the male parent.As for the production,the mix of the cultivars/varieties is one of the primary problems in China,which leads to a lot of economic losses to the orchards.While,the identification of the hazelnut cultivars now is still depending on the botanical characters,that is low efficiency and inaccurate.Thus,it is important to establish an efficient cultivar identification method for Ping'ou hybrid hazelnuts.Microsatellites or simple sequence repeats(SSRs) are tandem repeats of short DNA sequences extensively distributed throughout the whole genome in both coding and non-coding regions and are considered ideal molecular markers.Compared with genomic SSRs,EST-SSRs have several special advantages due to either a relatively higher transferability or a potential gene function,which have been evaluated in many studies.The objective of this study is to establish an accurate and high efficiency method for Ping'ou hybrid hazelnut cultivar identification.43 cultivars/varieties of Ping'ou hybrid hazelnut introduced throughout China were used in this experiment.12 polymorphic EST-SSR markers developed in the previous study were used to select the high efficient marker combination for cultivar identification.The result showed that the PIC value of the 12 EST-SSR markers among the 43 samples ranged from 0.3800 to 0.7839,with the average value of 0.5113.All the markers showed good polymorphism and amplification result when visualized by capillary electrophoresis.The genetic relationship of Ping'ou hybrid hazelnut showed complexity due to their breeding method.The genetic distance of Bokehong and Ping'ou 62,Ping'ou 3 and Ping'ou 7,Ping'ou 30 and Ping'ou 48 were the lowest among all the samples.Finally,the combination of four EST-SSR markers,CAF-2,CAF-3,CAF-12 and CAF-13,could identify 43 cultivars/varieties of Ping'ou hybrid hazelnut,the combination of CAF-2 and CAF-13 could identify 16 main cultivars/varieties.The result offered an accurate,convenient and efficiency method for cultivar identification of Ping'ou hybrid hazelnut and could also offer reference for researches in other Corylus L.species.