榅桲实生苗抗寒性和AFLP遗传多样性分析

Seedlings Cold Resistance and AFLP Genetic Analysis of Cydonia oblonga

为更好地了解查榅桲的生长发育规律和品种划分,搜集新疆喀什、新疆阿克苏、陕西西安、山东曲阜、福建明溪、北京和智利9个不同种源的榅桲果实,取其种子进行层积、育苗,对所得实生苗的生长动态、抗寒性和AFLP遗传多样性进行初步探讨,并得出以下主要结论：（1）榅桲实生苗生长可划分为4个阶段——出苗期、生长初期、速生期和生长后期,其中处于速生阶段苗木的株高和地径生长量均达到全年总量的70%。（2）不同产地榅桲枝条的细胞伤害度随着温度的降低而增加。但智利榅桲枝条的相对电导度（4℃时高达63.31%）显著高于其他产地榅桲,抗寒性最差;新疆阿克苏2种类型的榅桲（苹果型和梗瘤型）的相对电导度（-16℃时分别是27.03%和47.17%）低于其他地区的榅桲,抗寒性较好。（3）应用AFLP技术筛选出的10对分辨率高的引物组合共扩增出310个总位点,其中多态性条带210个,多态位点比率达69.41%,说明其分子遗传水平上的多态性丰富度不高。以相似系数值0.328作为划分标准,可将9种榅桲资源划分为2类。（4）根据NTSYSpc2.10分析,9份榅桲种质之间相似性系数在0.10-0.50,以相似系数值0.328作为划分标准,可将9种榅桲资源划分为2类。

In order to better understand the growth nine provenances Mingxi of Cydonia Fujian, Beijing and research on different oblonga from Akesu Chile were selected seedlings and varieties division of the Quince （Cydonia oblonga Mill）, Xinjiang, Kashi Xinjiang, Xi＇ an Shannxi, Qufu Shandong, for this experiment, taking their seeds for seedlings and for growth dynamic, cold resistance and AFLP genetic diversity was carried out. The main results were submitted as follows： （1） the proceeds of Cydonia oblonga seedling growth can be divided into four stages： the seedling stage, the initial stage of growth, the fast-growing period and the late stage; during the fast-growing period, the height and diameter growth and volume accounts for about 70% of the annual total; （2） cell damage degree of different provenances of Cydonia oblonga seedling increased with the decrease of temperature, the relative conductivity of Chile Cydonia oblonga （4~C, 63.31%） was higher than that of the other samples significantly and its cold resistance was the worst, the relative conductivity of Akesu Xinjiang Cydonia oblonga was lower than that of the other samples and its cold resistance was the best; （3） based on AFLP markers, ten selective primers were screened and 210 polymorphic bands were observed from total 310 bands. The polymorphic percentage （PPB） was 69.41%, the analysis indicated that there were no large genetic variations in molecular levels; （4） according to the NTSYSpc2.10, the genetic similarity coefficient of the nine quince germplasm was between 0.10 and 0.50, two groups of taxes were assigned based on the results of cluster analysis with the genetic similarity coefficient at 0.328.