两种常用消毒药物对绿菊花草光合速率的影响OA

To investigate the effects of common disinfectants,sodium chloride(NaCl)and potassium permanga-nate(KMnO4),on the photosynthetic performance of Cabomba caroliniana,the respiratory rate,net photosyn-thetic rate,and total photosynthetic rate were measured using an oxygen electrode under optimal light intensity following treatment with different mass concentrations of NaCl(0%,0.25%,0.50%,1.00%)and KMnO4(1mg/L,10mg/L).The results showed that exposure to different concentrations of NaCl for 3 days had no signifi-cant effect on the respiratory rate and total photosynthetic rate of C.caroliniana under optimal light(P>0.05),but had significant effect on the net photosynthetic rate(P<0.05).The net photosynthetic rate increased signifi-cantly in the 0.25%NaCl group(P<0.05)and then decreased gradually with increasing NaCl concentration.However,no significant differences were observed between the 0.50%and 1.00%groups and the control(0%)group(P>0.05).Different KMnO4 concentrations and soaking times(12 h,24 h)had no significant effect on the respiratory rate(P>0.05),but had a highly significant effect on both the net photosynthetic rate and total photosynthetic rate of C.caroliniana(P<0.01).After 12 h of exposure,no significant differences in net photo-synthetic rate or total photosynthetic rate were found between the 1 mg/L KMnO4 group and the control group(P>0.05).However,all other KMnO4 treatments resulted in highly significant decreases in the photosynthetic rate of C.caroliniana(P<0.01).These results indicate that C.caroliniana exhibits moderate salt tolerance,and low concentrations of NaCl can promote its photosynthesis.For disinfection purposes,1 mg/L KMnO4 solution can be used for C.caroliniana,but the soaking time should not exceed 12 h.