Toxicity Analysis Of Arecoline On The Intergenerational Development Of Aedes Aegypti And Its Inhibitory Effect On Chitinase

Areca catechu is a palm plant,and its arecoline has many effects such as insecticidal,antibacterial and cytotoxic.In this paper,Aedes aegypti was used as the target organism.Based on the sublethal concentration of arecoline,the effects of arecoline on developmental toxicity,neurotoxicity and detoxification enzymes of Aedes aegypti were studied,and the teratogenic mechanism of arecoline was preliminarily discussed.The main results are as follows:1.The toxicity of arecoline to Aedes aegypti was determined.After 48 h treatment,the LC₅₀ value of arecoline was 72.675 mg/L;52,58 and 63 mg/L can be used as sublethal concentrations.2.The effects of arecoline on the developmental parameters of parents and offspring of Aedes aegypti at sublethal concentration were measured.It was found that during the emergence stage of the test insects,the adults would have deformed shapes in different degrees,even leading to leg loss.The pupation rate,emergence rate,average egg production and hatching rate of parents decreased significantly with the increase of treatment concentration.There was no significant difference in the above growth indexes among the offspring.3.The postlethal effect of arecoline on larvae was measured at sublethal concentration.It was found that the cumulative mortality rate,dead pupa rate,abnormal emergency rate and leg loss rate of larvae increased with the increase of treatment concentration after arecoline treatment.The pupa weight,head length and width showed a downward trend,and the indexes measured at the concentrations of 58 and63 mg/L were significantly different from those of the control.4.The effects of arecoline on acetylcholinesterase and toxine receptor in the test insects were measured at sublethal concentration.It was found that the activity of acetylcholinesterase in the test insects increased gradually with the increase of drug concentration,and there were significant differences between the treatment group and the control group.The degree of activation of toxine receptor in the larvae was significantly higher than that in the control group,but there was no significant difference between the concentrations.The effect of arecoline on the detoxification ability of larvae was found.The results showed that with the increase of the concentration of chemicals,the content of reduced glutathione in the test worms increased gradually,and the activity of GST enzyme increased gradually.There was a significant difference between each drug treatment group and the control group.5.By measuring the changes of transcription level of adult Aedes aegypti with leg（deletion）deformity,the related genes such as nfkb-1,rel2,uap,cht1 and cht2 were screened out for fluorescence quantitative analysis.The results showed that the relative expression of nfkb-1 and rel2 increased and the immune ability was enhanced.The relative expression of uap,cht1 and cht2 decreased,and the metabolism of amino acids and nucleotides decreased.6.The effects of arecoline on the immune ability and chitinase of test insects at sublethal concentration were determined.It was found that the activity of phenol oxidase in the drug treatment group was significantly higher than that in the control group.The chitinase activity of larvae showed an upward trend,while that of adults showed a downward trend.Further determination of the effects of pesticides on the chitin content of test insects showed that with the increase of pesticide concentration,the chitin content of pupae,adults and legs of test insects decreased gradually,and the63 mg/L treatment was significantly different from the control.To sum up,arecoline has an effect on the F0 development parameters of Aedes aegypti,but has no genotoxicity on F1.The immune homeostasis is broken,and the decrease of chitinase and chitin content may be one of the reasons for mosquito leg deformity.