The Effects Of Sublethal Thiamethoxam On The Social Behaviors Of The Ant Camponotus Japonicus

The use of chemical agentia can ensure the stability of agricultural production,but it will also bring about some negative effects.Neonicotinoid insecticide was a highly effective and low-toxic insecticide and was used to prevent pests of sucking mouthparts,such as planthoppers,leafhoppers and aphids.Neonicotinoid insecticides are highly toxic to target pests,but they also have adverse effects on non-target pests.Thiamethoxam is a neonicotinoid insecticide with a wide range of uses in agricultural production.It was mainly used for controlling brown planthopper in rice and was mainly used for controlling aphids and leafhoppers in fruit trees.In these ecosystems,there are also some social insects,bees and ants.Under normal circumstances,the ant(Camponotus japonicus)does not directly harm crops,but it forms a mutually beneficial relationship with some agricultural pests.In the prevention and control of agricultural pests,the ants(Camponotus japonicus)were bound to be affected by chemical agentia.Therefore,the study of the influence of chemical pesticides on the social behaviors of the ants(Camponotus japonicus)provides new information for the mechanism of non-target insects affecting neonicotinoid insecticides.1.The sublethal thiamethoxam changed the foraging and discrimination ability of the ant Camponotus japonicusThe effect of sublethal thiamethoxam on the ants(Camponotus japonicus)was mainly manifested through social behaviors,such as the behavior of foraging,attacking,and discrimination.C.japonicus workers were treated by the sublethal dose of thiamethoxam with 20%mortality to prepare the treated workers(TG);The untreated workers(control,CK)were co-reared in one nest with T workers at the ratio of 1:1 for 5 days,and then collected to prepare the affected workers(AG).In terms of foraging behavior,at the individual level,there was no significant difference in the probability of discovering food between differently treated groups;at the population level,the recruitment behavior of differently treated groups were inconsistent,and there was recruitment behavior in the control group.The other two groups did not show it.The Y-tube test and the Electroantennograhy(EAG)response were used to study the ability of ants to recognize the relatives in different treatment groups.Ants in the control group were able to identify siblings in the nestmate or non-nestmate at both ends of the Y-shaped tube,but the treatment and indirect affected groups were not very good.In the control group,the EAG response of ant on the cuticular hydrocarbons extracts of non-nestmate ants were higher than those of the treatment group and the indirect affected group.The aggressive behavior to other species ants,the control groups showed more intensely,the treated groups performed weak.Through the experiments,it has been found that sublethal thiamethoxam on ant(Camponotus japonicus)colonies have reduced foraging efficiency at the population level,and their ability to identify siblings with nestmate and non-nestmate has decreased.Frequent exchanges between ants,some of the unfavorable effects can also occur on ants that have not been in direct contact with pesticides.2.Transcriptome Sequencing Analysis of the sublethal thiamethoxam on ant Camponotus japonicusBy transcriptome sequencing,ants from different treated groups were analyzed.By performing comparative analysis of transcriptome data,we can obtain differentially expressed genes among different treatments.The differentially expressed genes were analyzed by GO enrichment and the KEGG pathway.The biological processes involved in the differentially expressed genes and the signal transduction pathways involved were known.Among the differentially expressed genes,some genes were either up-regulated or down-regulated in the direct and indirect affected groups,and they also have some genes that are expressed individually.These genes were analyzed by GO enrichment and KEGG enrichment.The processes involved in these genes are mainly metabolic processes.During transcriptome analysis,we mainly analyzed genes involved in cuticular hydrocarbons synthesis.The results of the analysis showed that there were differences in the expression of these genes among the ants in different treated groups,some of which showed up-regulation and some showed down-regulation.