环境因子对大石鸡种群遗传多样性的影响

Effects of environmental factors on the population genetic diversity in the rusty-necklaced partridge(Alectoris magna)

分别以mtDNA的非编码基因D-loop和编码基因Cytb为分子标记,研究了大石鸡分布区内12个种群遗传多样性与环境因子之间的相关性.173个样本的D-loop部分序列(1127 bp)中共发现了34个多态位点,定义了44种单倍型;230个样本的Cytb部分序列(807 bp)中共发现了13个多态位点,定义了14种单倍型.基于D-loop和Cytb的单倍型多样性和核苷酸多样性与样本量之间均无显著相关性.所有的种群遗传多样性与环境因子相关性检验中,基于D-loop的核苷酸多样性与降水量的负相关、基于Cytb的单倍型多样性与纬度和相对湿度变异系数的负相关以及基于Cytb的核苷酸多样性与相对湿度变异系数的负相关达到了显著水平,说明纬度、降水和相对湿度变异系数是影响大石鸡遗传多样性的主导因子,低纬度、干旱以及气候稳定的环境下,大石鸡的遗传多样性更高.

Correlation between environmental factors and genetic diversity of 12 populations throughout their ranges was examined using mitochondrial DNA（mtDNA） non-coding control region（D-loop） and coding Cytochrome b（Cytb）.A total of 1127 nucleotides of D-loop were sequenced from 173 samples.Forty-four haplotypes were defined by 34 variable sites.A total of 807 nucleotides of Cytb were sequenced from 230 samples.Fourteen haplotypes were defined by 13 variable sites.The correlation between all of the genetic diversity indexes and the sample size was not statistically significant.Based on D-loop sequences,a significant negative relationship was observed between nucleotide diversity and precipitation.However,based on Cytb sequences,significant negative relationships were observed between haplotype diversity and latitude and variation coefficient of relative humidity, as well as between nucleotide diversity and variation coefficient of relative humidity.Latitude,precipitation and variation coefficient of relative humidity were the dominant factors that influenced the genetic diversity of the rusty-necklaced partridge.The genetic diversity of the rusty-necklaced partridge tended to increase in the environment with a lower latitude,less rainfall and a more stable climate.