Metabolism Mechanism Of Agasicles Hygrophila In Response To High Temperature

Alternanthera philoxeroides(Mart.)Griseb(Amaranthaceae)is considered as an invasive species and has been spread to many countries.The spread of A.philoxeroides has had negative impacts on the economy,environment and society.Agasicles hygrophila(Selman & Vogt)(Chrysomelidae),the alligatorweed flea beetle,is a classical biological agent that has proven effective in controlling alligatorweed and is presently used in many countries.Field surveys showed that the population density of A.hygrophila decreases sharply during July and August in Hunan province,China.Therefore,it can not control the alligator weed efficiently,resulting in agricultural product loss and ecological damage during this time.In this study,we focused on the metabolome and transcriptome of A.hygrophila in response to high temperature,aiming to elucidate the metabolism mechanism of A.hygrophila by differential metabolites and genes expression levels under high-temperature stress.1.Differential metabolites of A.hygrophila under high temperature stress were analyzed by liquid chromatography-mass spectrometry(LC-MS).A total of 67 differential metabolites were identified under positive ion mode and 65 differential metabolites were identified under negative ion mode.We used principal component analys is(PCA)and orthogonal projections to latent structures-discriminant analys is(OPLS-DA)to analyze 132 different metabolites,and found there were significant differences between normal temperature(30?)group and high temperature(39?)group.The differential metabolites were mainly involved in the metabolic pathways of animo acids metabolism,galactose metabolism,fatty acid synthesis and metabolism,et al.2.The differential metabolites of A.hygrophila under high temperature stress were analyzed by gas chromatography-mass spectrometry(GC-MS).We identified 91 differential metabolites between normal temperature(30?)group and high temperature(39?)group.We used PCA and OPLS-DA to analyze 91 differential metabolites,and found there were significant differences between these two groups.The differential metabolites mainly involved in the metabolic pathways of animo acids metabolism,citrate cycle,pantothenate and CoA biosynthesis,et al.3.Transcriptome sequencing was used to analyze the differentially expressed genes of Agasicles hygrophila under high temperature stress.There were 701 genes showed different expression levels between normal temperature(30?)group and high temperature(39?)group,of which 422 genes were up-regulated and 279 genes were down-regulated.Based on the A.hygrophila transcriptome data,82 AhCYP genes were identified.After high temperature stress treated,22 AhCYPs were up-regulated and 19 AhCYPs were down-regulated in females,8 AhCYPs were up-regulated and 12 AhCYPs were down-regulated in males.4.Target metabolome technique was used to detect amino acid content of A.hygrophila in reponse to high temperature stress.Twelve amino acids in females and 18 amino acids in males showed significant differences in animo acid content after high temperature stress.Differential amino acids mixture was injected into A.hygrophila females and males.The results showed that the survival days,fecundities of females and egg hatching rates were significantly increased in response to high temperature.