中国北方黑唇苜蓿盲蝽种群遗传多样性和遗传分化分析

【目的】本研究旨在基于线粒体基因序列检测中国北方黑唇苜蓿盲蝽Adelphocoris nigritylus地理种群遗传多样性和遗传分化。【方法】使用采自中国北方地区12个地理种群的233头黑唇苜蓿盲蝽成虫标本,通过PCR扩增线粒体ND5,ND4和Cytb基因片段;利用MEGA,DnaSP和Arlequin等软件对黑唇苜蓿盲蝽种群遗传多样性、遗传分化和分子变异等进行分析。【结果】本研究获得的黑唇苜蓿盲蝽线粒体ND5,ND4和Cytb基因的串联序列长度为2226 bp,共检测到87个单倍型,其中单倍型Hap3,Hap9和Hap8被多个个体共享。遗传多样性分析结果显示,黑唇苜蓿盲蝽种群具有较高的单倍型多样性和较低的核苷酸多样性。SAMOVA分析结果表明遗传变异主要来自组内的种群间;Mantel检验结果显示黑唇苜蓿盲蝽种群间遗传距离与地理距离两者不具有显著相关性。【结论】中国北方黑唇苜蓿盲蝽种群整体遗传多样性较高,可能经历了近期种群扩张。

大兴安岭南麓东北马鹿种群遗传多样性分析

由于人类活动干扰及自然环境变化,东北马鹿(Cervus elaphus xanthopygus)的生存面临诸多问题。为掌握东北马鹿遗传多样性现状,进而为马鹿种群的健康状况提供评估依据,利用线粒体Cyt b基因和微卫星2种分子标记对内蒙古大兴安岭南麓高格斯台罕乌拉国家级自然保护区内的东北马鹿进行种群遗传多样性评估。结果表明:246份新鲜马鹿粪便隶属于182只个体;微卫星标记表明平均期望杂合度为(0.729±0.016),平均观测杂合度为(0.768±0.029),线粒体标记表明单倍型多样性为(0.347±0.035),核苷酸多样性为(0.248±0.025)%,种群存在较高比例的稀有单倍型(33.33%)。该地区马鹿种群遗传多样性处于中等偏低水平,未来可能存在单倍型丢失的风险。因此,为避免出现遗传多样性下降的风险,建议该地区加强对马鹿种群的管理与保护,并促进与邻近区域马鹿个体的基因交流。

Genetic Comparison among Rhynchophorus ferrugineus and Four Rhynchophorus Species

Genetic comparison between Rhynchophorus ferrugineus （Coleoptera： Curculionidae： Rhynchophorinae） and other four Rhynchophorus spp. such as R. bilineatus, R. phoenicis, R. cruentatus and R. palmarum was investigated using partial sequences of Cytochrome c oxidase subunit I （COl） mitochondrial gene. The number ofpolymorphic sites ranged from 79 to 102 while the genetic distances ranged from 0.058 to 0.095. The number of polymorphic sites, genetic distances and phylogenetic relationships among R. ferrugineus and the other four tested species revealed that R.ferrugineus was more closely related to R. bilineatus while it was distantly related to R. palmarum. It is possible to rank the five tested species as follows： R.ferrugineus, R. bilineatus, R. phoenicis, R. cruentatus and R. palmarum. The result of this study is the first step of the revision of the uncertain taxonomic status and phylogenetic relationships among the Rhynchophorus genus. Further analysis should be performed using other Rhynchophorus species as well as other molecular markers.