越橘叶片转录组SSR发掘及其多态性研究

SSR Mining and Polymorphism Analysis in Leaf Transcriptome of Blueberry

对高丛越橘品种‘布里吉塔’叶片转录组序列进行了简单重复序列(SSR)位点搜索和分析,发现了22 058个SSR位点,总发生频率为21.32%。SSR重复类型以二核苷酸发生频率最高(77.70%),三核苷酸次之(21.45%)。选用53对SSR引物在8个越橘属植物中进行PCR扩增,筛选出15对条带清晰且能稳定扩增的SSR核心引物。使用核心引物对39份越橘属种质进行分析,有效等位基因数最大值为7.11(Vc SSR19),最小值为1.41(Vc SSR41),平均值为3.90。香农多样性指数变化范围是0.64~2.31,平均值为1.55。观察杂合度和期望杂合度的变化范围分别是0.050~0.900和0.293~0.870,平均值分别为0.457和0.677。使用5对引物可以完全区分39份种质中的38份。南高丛越橘品种‘莱格西’和‘蓝雨’与蔓越橘品种、越橘属野生种具有更近的亲缘关系,是与野生种进行杂交育种的合适种质。

Simple sequence repeat（SSR）loci were searched and analyzed in the leaf transcriptomic sequence of Vaccinium corymbosum‘Brigitta＇. The frequency of SSR was 21.32%,accounting for 22 058 SSR loci. The highest type of SSR motif was dinucleotides with the frequency of 77.70%,followed by trinucleotides with the frequency of 21.45%. Fifty-three random pairs of primers were used to perform polymerase chain reaction（PCR）in 8 accessions in Vaccinium genus. A total of 15 pairs of core primers with clear and stable amplification bands were screened from above primers. Genetic diversity of 39 accessions in genus of Vaccinium was estimated using the 15 core primers. The results showed that the maximum number of effective alleles was 7.11（Vc SSR19）and the minimum value was 1.41（Vc SSR41）,with an average value of 3.90. The average of Shannon diversity index was 1.55,ranging from 0.64 to 2.31. The range of observed heterozygosity and expected heterozygosity were 0.050–0.900 and 0.293–0.870,with mean values of 0.457 and 0.677,respectively. Five polymorphic loci could be used to distinguish 38 accessions. Southern highbush blueberry cultivars‘Legacy＇and‘Bluerainare＇were more closely related to cranberry cultivars and wild relatives of Vaccinium,which would be suitable cultivars for cross breeding with wild species in Vaccinium.