甜瓜SSR标记在葫芦科不同作物间的通用性分析

Generality Analysis of Melon SSR Markers in Different Cucurbit Crops

微卫星标记(SSR)在近缘物种间具有通用性,因其高效率、低成本可广泛用于跨物种间的遗传多样性分析、基因定位和图谱构建等。本试验基于甜瓜基因组测序结果开发了120对SSR标记,研究其在8种葫芦科作物间的通用性及作物内的多态性,并利用NTSYS软件分析37份不同瓜类作物材料间的遗传多样性。结果显示,114对标记均在甜瓜基因组中得到有效扩增,黄瓜中有108对标记有效扩增,通用性比率为94.7%,南瓜中能有效扩增标记最少,其通用性比率也达到了41.2%,在8种葫芦科作物间均通用的标记有29对;通过对通用性标记的多态性分析表明,甜瓜多态性比率最高为61.4%,西瓜、黄瓜、苦瓜、冬瓜、西葫芦、南瓜和丝瓜多态性比率分别为32.5%、14%、4.4%、8.8%、3.5%、13.2%和11.4%;不同作物间的平均遗传相似系数在0.70~0.83之间,其中甜瓜和黄瓜平均遗传相似系数较小,亲缘关系较近,西葫芦和南瓜间的平均遗传相似系数最小,亲缘关系最近。这些通用性标记将有利于提高葫芦科作物整体分子生物学研究水平。

Microsatellite markers（SSR） have generality among closely related species. Because of their high efficiency and low cost, SSR can be widely used in genetic diversity analysis, gene mapping and map construction among different species. In this study, a total of 120 pairs of SSR markers were successfully developed based on melon genomic sequences, the transferability and polymorphism of which in eight cucurbit crops were analyzed.Also, the genetic diversity of 37 cucurbit crops was analyzed by by NTSYS software. The results showed that all114 pairs of markers were effectively amplified in melon. 108 pairs of markers（94.7%） were successfully amplified in cucumber, while the SSR markers which could be amplified in pumpkin was the least, but its generality ratio also reached 41.2%. 29 pairs of SSR markers were successfully amplified in all the eight cucurbit crops. The polymorphic analysis of markers with generality indicated that the polymorphism rate of melon was the highest（61.4%）, and that of watermelon, cucumber, bitter gourd, wax gourd, Cucurbita pepo, pumpkin and luffa was 32.5%,14%, 4.4%, 8.8%, 3.5%, 13.2% and 11.4%, respectively. The average genetic similarity coefficient among eight cucurbit crops ranged from 0.70~0.83. Of them, the genetic similarity coefficient melon and cucumber was small,indicating a closer genetic relationship, and Cucurbita pepo and pumpkin had the smallest genetic similarity coefficient, so they were the most closely related. These transferable markers would be helpful for the molecular biology research of cucurbitaceae crops.