【摘要】 应用荧光定量PCR技术对蓝藻水华暴发期间太湖和巢湖水体中产毒微囊藻和总微囊藻种群丰度的空间分布进行了研究.分别以微囊藻毒素合成基因基因家族成员mcyD和小核糖体16S rDNA序列构建定量PCR标准曲线,研究产毒微囊藻和总微囊藻种群丰度.结果表明:太湖和巢湖微囊藻种群由产毒微囊藻和非产毒微囊藻组成;蓝藻水华暴发期间,微囊藻种群组成及其丰度分布具有明显的空间差异性:太湖产毒微囊藻种群丰度为9.89×104～4.51×106 copies mL-1,产毒微囊藻占总微囊藻种群的比例为20.5%～38.1%;巢湖产毒微囊藻种群丰度为4.12×104～5.44×106 copies mL-1,其占总微囊藻种群的比例为8.4%～96.6%.总的来说,富营养化严重的湖区总微囊藻和产毒微囊藻种群丰度较高,产毒微囊藻占总微囊藻种群的比例也较高.图7表3参29更多还原

【Abstract】 The spatial changes in abundances of microcystin-producing and total Microcystis populations in the Taihu Lake and the Chaohu Lake during water bloom were investigated using quantitative real-time PCR(qPCR) techniques.Primer sets based on the small subunit ribosomal RNA gene(16S rRNA) and the microcystin synthetase gene(mcyD) were used to target the total Microcystis population and the potential microcystin-producing subpopulation,respectively.The results showed that Microcystis existed as a mixed population of potentially toxic and non-toxic genotypes in two lakes.There was significantly spatial variation in the abundance of microcystin-producing Microcystis in the Taihu Lake and the Chaohu Lake.The abundance of microsystin-producing Microcysits subpopulation ranged from 9.89×104 to 4.51×106 copies mL-1 in the Taihu Lake and the ratio of its abundance to total Microcystis varied from 20.5% to 35.3%.The abundance of microsystin-producing Microcysits in the Chaohu Lake ranged from 4.12×104 to 5.44×106 copies mL-1,making up 8.4%~96.6% of the total Microcysits.In one word,the abundance of microcystin-producing and total Microcystis population increased with increasing trophic level of the lake,and the propotion of microsystin-producing Microcysits to the total Microcystis followed the same trendency,which suggested that the Chaohu Lake might face greater risk of toxic cyanobacterial bloom pollution than the Taihu Lake.Fig 7,Tab 3,Ref 29更多还原