摘要:
0,0-二甲基-(2,2,2-三氯-1-羟基乙基)磷酸酯(敌百虫)为广谱杀虫剂,用途广泛,但对藻类的毒理学效应研究还有待完善。采用4种受试藻样,设置5个敌百虫浓度组(1、5、10、50和100 mg·L-1)和对照组,实验周期40 d,藻细胞的初始接种密度106 cells mL-1,光暗比12 h/12 h,24 h曝气,24 h磁力搅拌,实验温度25 ℃,pH 6.8,每隔24 h取样。结果表明:5 mg·L-1、10 mg·L-1、50 mg·L-1浓度的敌百虫对铜绿微囊藻和小球藻的生长有促进作用,其中以50 mg·L-1浓度组的促进作用最为显著,促进作用主要表现在生长峰值的延后以及生长对数期的延长,而高剂量(100 mg·L-1)的敌百虫则有抑制藻生长的作用。取50 mg·L-1敌百虫浓度组以及铜绿微囊藻和小球藻作进一步深入研究,结果表明:50 mg·L-1敌百虫浓度组的叶绿素a含量峰值比对照组高30%,细胞体内的SOD、ATP含量都高于对照组。敌百虫的使用浓度通常在0.1~1.0 mg·L-1,低于本实验最佳浓度。本实验中1 mg·L-1敌百虫对藻生长影响效果不明显。
Abstract:
0,0-two-(2,2,2-three chloro-1-hydroxy ethyl) phosphate (trichlorfon) is widely used as pesticides, while its toxic effect on algae is still not well understood. The experiment adopts four algal species to be exposed to 5 different trichlorfon concentration groups (1, 5, 10, 50, 100 mg·L-1) and 0 mg·L-1 as control group. The experimental period is 40 days, and the initial inoculation density of algal cells is 106 cells mL-1 with the light dark ratio 12 h/12 h, 24 h aeration, 24 h magnetic stirring, the experimental temperature 25 ℃, pH 6.8. Samples are taken in every 24 h. Results show that 5 mg·L-1, 10 mg·L-1 and 50 mg·L-1 of trichlorfon has a promoting effect on the growth of Microcystis aeruginosa and Chlorella sp. CHX-1, and thereinto 50 mg·L-1 group has the most significant effect. The promoting effect is mainly manifested in the delay of the growth peak and the extension of the exponential phase, and high doses of trichlorfon (100 mg·L-1) inhibit the growth of algae. The further study shows that the peak of algal Chl a in 50 mg·L-1 trichlorfon group is 30% higher than the control group, and the SOD content and ATP content in the cells are higher than control group. Working concentration of trichlorfon is 0.1-1.0 mg·L-1, which is lower than the concentration of this study. The 1 mg·L-1 trichlorfon group has no obvious effect on the growth of algae.