【摘要】 采用线粒体DNA控制区(D-loop)序列对2015年和2017年长江口中华鲟(Acipenser sinensis)幼鱼样本进行了遗传多样性分析。2015年的682个样本共检测出11个单倍型,2017年的158个样本共检测出8个单倍型。2015年和2017年长江口中华鲟幼鱼的平均单倍型多样性(h)为0. 857±0. 006,核苷酸多样性(π)为0. 010 2±0. 005 5,均低于截流前数据(h=0. 949±0. 010;π=0. 011±0. 006)。分子变异方差分析(AMOVA)显示,中华鲟幼鱼的遗传变异主要来自于群体内,但其年度样本之间出现了中等程度的遗传分化。更多还原

【Abstract】 Chinese sturgeon Acipenser sinensis,a typically anadromous fish,is mainly distributed in the continent shelf of the Yellow and East China Seas,and the middle and lower reaches of the Yangtze River.Extensive studies have shown that the natural resources of wild Chinese sturgeon decreased rapidly since the closure of Gezhouba Dam. Chinese sturgeon is on the verge of extinction and was listed as a category Ⅰnationally protected species in China in 1988. And in 2010,this species was considered by the International Union for the Conservation of Nature( IUCN) as critically endangered. In 2013,2015 and 2017,natural propagation of Chinese sturgeon was not observed in the spawning ground,thus it faces survival crisis.Muscle and fin samples of juvenile Chinese sturgeon were collected from the Yangtze Estuary in 2015 and2017. A 462 bp mitochondrial D-loop sequence was amplified by PCR and then used for genetic analysis. We detected 11 haplotypes of 672 samples in 2015 and 8 haplotypes of 158 samples in 2017. The average haplotype diversity( h) of 2015 and 2017 was 0. 857 ± 0. 006,and the average nucleotide diversity( π) was0. 010 2 ± 0. 005 5. The genetic diversity was lower than that of the spawning population samples in 1995—2000( h = 0. 949 ± 0. 010; π = 0. 011 ± 0. 006). AMOVA analysis indicated that 91. 70% of the genetic variability occurred within each year’s juvenile populations. The value of Fstshows a middle genetic diversity between annual samples.更多还原