Biochemical Mechanism Of Frankliniella Occidentalis (Perganda) Adaptation To The Defenses Of Kidney Bean And Broad Bean Plants

Frankliniella occidentalis?Pergande?is one of the most important invasive pests in China,which has caused great harm to crops.F.occidentalis had fed on the favorite kidney bean plants and the non-favorite broad bean plants respectively,and the detoxification enzymes?CarE?GSTs and P450?,protective enzymes?CAT,POD and SOD?,digestive enzymes??-amylase,Trypsin and Tryptase?,and nutrients?total protein,total sugar,total lipids?in F.occidentalis were determined.In order to study the adaptability of F.occidentalis to the secondary substances produced by the non-favorite pepper,the different concentrations of capsaicin were added into food for F.occidentalis,and the detoxification enzymes?CarE?GSTs and MFO?and target enzyme?AchE?were determined.The results would revealed adaptation mechanism of F.occidentalis to host plants,and the which would provide theoretical basis for the prevention and control.The results were as follows:1 The adaptation of F.occidentalis in different generations to kidney bean plantsAfter converting F.occidentalis from the bean pod to the favorite kidney bean plants,the activities of the detoxification enzymes in F₁ were significantly higher than conteol.There was small difference in CarE activity between F₁ and F₂ in 2nd instar nymphs,and F₃ was the lowest with 0.3516 nmol/min/mg prot.There was no significant difference in CarE activity between F₂and F₃ in adults,and F₁ was the highest that was 0.4321 nmol/min/mg prot.The activitis of the GSTs in the 2nd instar nymphs and adults were simiar,F₁>F₂>F₃.P450 activities in2nd instar nymphswere:F₁>F₂>F₃,but their activities in adults in F₁were the highestwith,0.0305nmol/min/mg prot,and the difference between in F₂ and F₃ was not obvious.The enzyme activities of CarE and P450 in adultwere significantly higher than that of 2nd instar nymphs,but in the F₂,the difference of GSTs activity between adult and 2nd instar nymphs was not significant.The activities of protective enzymes in F₁ were significantly greater than that in the control group.The CAT and SOD activities of 2nd instar nymphs and adults were F₁>F₂>F₃.There was no significant difference in POD activity in 2nd instar nymphs between F₁ and F₂,but the enzyme activity of F₃ decreased,and down to 1.8809 nmol/min/mg prot.The POD activities of adults were F₁>F₂>F₃.The activities of protective enzymes in adult were significantly higher than that of2nd instar nymphs.The?-amylase and Trypsin activities of F₁ were significantly lower than control,while the Tryptase activity was not significantly different.In F₁,?-amylase activity in 2nd instar nymphs was the lowest,which was 0.0673 nmol/min/mg prot.There was no significant difference in F₂and F₃.Trypsin activity was F₁<F₂<F₃.There was no significant difference in the activity of Tryptasein2nd instar nymphs among generations about,but there were significant changes in adults,F₁<F₂<F_3.The'digestive enzymes in 2nd instar nymphs were significantly lower than that of adults.The nutrients of F.occidentalis were significantly lower than the control group,and there was no significant difference in nutrient content between the three generations.However,the nutrient content of 2nd instar nymphs was not higher than adults.2 The adaptation of F.occidentalis in different generations on to broad bean plantsThe GSTs enzyme activity was inhibited when F.occidentalis were transformed from the favorite bean pod to non-favorite broad bean plants,and the activity reduced with generations,which were lower than control significantly.The activities of P450 in 2nd instar nymphs and adults were the lowest in the F₃,which were 0.0263 nmol/min/mg prot and 0.0379 nmol/min/mg prot respectively,while the changes in F₁ and F₂ were not significant.In different insect stagees,the activityiesof detoxification enzymes in adult were higher than that of 2nd instar nymphs.The activity of SOD enzyme in F.occidentalis was inhibited,and F₁>F₂>F₃.All activities of SOD were significantly lower than that in the control group.The activities of CAT and POD in the 2nd instar nymphs and adult were significantly higher than that of the control group,and F₁>F₂>F₃.It was found that the protective enzymes in adults were high than 2nd instar nymphs at same generation.The activities of?-amylase and Trypsin in F.occidentalis were not high than contaol,and the activities increased with generation increase.The activity of Tryptase was higher than that of control,but it decreased with generation increase.The changes of digestive enzymes were different,and activity in 2nd instar nymphs were lowerthan that of the adults.The nutrients of F.occidentalis didn't not change significantly within 3 generations,and the contents of total protein and total sugar in both adult and 2nd instar nymphs were lower than control,and only the content of total lipids was no significant difference compared with control.The nutrient content differed significantly,and the nutrients of 2nd instar nymphs than that of adults.3 The adaptation of F.occidentalis to broad bean plants in the short termF.occidentalis were transfered from the favorite bean pod to the non-favorite broad bean plants for 12h,24h,48h,72h and 96h.It was found that the activities of detoxifying enzymes increased with the extension of treatment time,and the enzyme activity increased firstly and then decreased.The activities of CarE and P450 were the lowest at 12 h,and were the highest at 72 h.The GSTs activity increased with the increase of the processing time,ans was as high as 18.8453nmol/min/mg prot at 96 h.The change of protective enzymes activity also increased and then decreased.,Tthe activities of enzymes were lowest at 12 h,and whichwere highest at 48h.However,the activitiesof digestive enzymes were reverse,and which decreased firstly and then increased with the increase of processing time.The?-amylase activity was the lowest at 48 h,with0.0606 nmol/min/mg prot,and was the highest aat 96 h,with 0.0662 nmol/min/mg prot.The activities of Trypsin and Tryptasewere the lowest at 48h,and which was the highest at 12h.The content of total protein decreased firstly and then increased with the increase of the processing time.However,the contents of total sugar and total lipids decreased with theextension of treatment time.4 The adaptation of the female adults of F.occidentalis on non-volatile secondary substance of capsaicinDifferent concentrations of capsaicin were added to the feed for F.occidentalis for 48 h,72 h and 96 h respectively,and the adapation of F.occidentalis was anlyzed.Lower concentrations of capsaicin could induce the activities of GSTs,AChE and MFO significantly increase but when F.occidentalis was exposured to higher concentrations,their activites significant ly decreased,and when the concentration of capsaicin was 1%,the enzyme activity was the lowest.CarE activity was inhibited by all capsaicin concentrations.No significant interaction between capsaicin concentration and treatment time was apparent for GSTs and AChE,but was for CarE and MFO;the longer the treatment time,the more significant the effect.