草甘膦对铜绿微囊藻生长和叶绿素荧光诱导动力学的影响

Effects of glyphosate on the growth and chlorophyll fluorescence induction dynamics of Microcystis aeruginosa PCC 7806

以铜绿微囊藻Microcystis aeruginosa PCC7806为研究对象,研究草甘膦Glyphosate胁迫下M.aeruginosa PCC7806生长、细胞色素含量的变化,以及对光合系统的影响.结果表明,当草甘膦质量浓度50mg/L时,M.aeruginosa PCC7806的生长受到显著抑制.通过线性回归分析,96h,草甘膦对铜绿微囊藻的半效应质量浓度EC_(50)为62.33mg/L.草甘膦质量浓度为200mg/L时能显著降低铜绿微囊藻单位细胞内叶绿素a和类胡萝卜素含量.光诱导动力学分析结果显示,低质量浓度下光系统没有表现出明显抑制,并表现出高于对照组的峰,而当质量浓度为100mg/L时,24h与96h结果发现O-J-I-P特征均已消失,表明其光合系统Ⅱ(PSⅡ)活性受到抑制.

The effects of the growth,cytochrome contents and chlorophyll fluorescence transient of M.aeruginosa PCC7806 under the stress of glyphosate were studied.The results indicated that the growth of M.aeruginosa PCC 7806 was significantly inhibited when the concentration of glyphosate was greater than 50 mg/L,By linear regression analysis,96 h,EC_（50） of glyphosate on M.aeruginosa PCC 7806 was 62.33 mg/L.AT the concentration of 200 mg/L,the contents of chlorophyll a and carotenoid could be significantly reduced.The result of chlorophyll fluorescence transient analysis showed that photosynthetic system was no significantly inhibited by the low concentration of glyphosate,and the peak showed higer than control group.But when the concentration of glyphosate was 100 mg/L,24 hand 96 hresults indicated that O-J-I-P features have disappeared,that the photosystem Ⅱ（PSⅡ）activity is inhibited.