紫茉莉不同花色植株遗传变异的ISSR分析

ISSR analysis of genetic variation of Mirabilis jalapa L. with different color flowers

采用简单序列重复区间扩增ISSR分子标记技术对分布于四川省成都市的紫茉莉（Mirabilis jalapa L．）3种不同花色群体进行了遗传变异分析．从100条引物筛选出5条引物进行PCR扩增，共扩增出67条清晰条带，其中62条条带具多态性．紫茉莉的等位多态性位点百分数（PPB）为92．54％，观测等位基因数（Na）为1．9254，有效等位基因数（Ne）为1．2354，Nei的基因多样性指数（H）为0．1562，Shannon指数（I）为0．2633．3种花色的遗传一致度在0．9054-0．9620之间，遗传距离在0．0388—0．0994之间，其中白色与黄色的遗传距离最小（0．0388），表现出最近的亲缘关系，黄色与紫色的遗传距离稍大（0．0994），亲缘关系稍远．紫茉莉的遗传变异主要存在于群体内，不同花色群体间的基因流（Nm）为1．279．

Mirabilis jalapa L. belong to the Mirabilis genus, which was classified in the family Nyctaginaceae. Inter-simple sequences repeats （ISSR） markers were used to analysis the genetic variation among 3 colonys with different color flowers. Of the 100 primers, 5 produced highly reproducible ISSR bands. These primers were carried out on 3 colonys ofM. jalapa with purple, white and yellow flowers from Chengdu City, Sichuan Province. High genetic variation was revealed. 67discernable DNA fragments were with 62 （92.54 % ） being polymorphic. Observed number of alleles （ Na ）, effective number of alleles （ Ne ）, Nei＇s gene diversity （ H ） and Shannon＇s information index （ I ） was 1. 925 4, 1. 235 4, 0. 156 2 and 0. 263 3, respectively. The values of genetic identity range from 0. 633 0 to 0.908 0. Nei＇s genetic distance in the 3 colonys was from 0. 038 8 to 0. 099 4, which was the closest（0.038 8）between colony with white flower and colony with yellow flower, and the farthest （0. 099 4 ） between colony with yellow flower and colony with purple flower. The genetic variation mainly occurred in colony of M. jalapa with same color flower, and Nm of different color populations was 1. 279.