Attraction And Synergistic Effect Of Spent Brewer's Yeast Protein Bait And Its Volatiles On Three Fruit Flies And Odorant Binding Protein Genes Expression In Bactrocera Dorsalis (Hendel)

Fruit flies(Diptera:Tephritidae)are severe insect pests of horticultural crops and cause massive damage to fruits and vegetables.The protein produced from spent brewer's yeast has a good attraction effect on tephritidae fruit flies species.The purpose of study was 1)To evaluate the indoor and outdoor average attractiveness of seven major spent brewer's yeast volatiles at different concentration;3-methyl-1-butanol,benzaldehyde,octyl acetate,phenethyl acetate,ethyl caprylate,benzyl cyanide and phenethyl alcohol at three adult physiological stages;pre-mating,post-mating and post-oviposition stages of male and female Bactrocera species;Bactrocera tau,B.cucurbitae and B.dorsalis.The results revealed that four volatiles;3-methyl-1-butanol,octyl acetate,ethyl caprylate and phenethyl alcohol were showed highest average attraction rate 60.36%to female and 54.76%to male at at 20%and 25%concentrations.B.cucurbitae in response to four volatiles collectively;3-methyl-1-butanol,phenethyl acetate,ethyl caprylate and phenethyl alcohol were showed average highest attraction 58.76%to female and 54.23%to male at 10%and 15%concentrations.B.dorsalis in response to four volatiles;phenethyl acetate,octyl acetate,ethyl caprylate and phenethyl alcohol showed average highest attraction rate 60.44%to female and 55.47%to male at at 15%and 25%concentrations.The attraction response of female was higher than male and the results further revealed that indoor experiment were consistent with outdoor experiment at three adult physiological stages of Bactrocera spp.in response to four attractive volatiles.2)To investigate the influence of single addition of four volatiles separately with torula yeast and protein bait at three adult physiological stages of male and female Bactrocera spp.(B.tau,B.cucurbitae and B.dorsalis)at indoor and outdoor conditions.The results revealed that the single addition of four most attractive volatile compounds were showed less attraction than control group at three adult physiological stages at indoor and outdoor conditions respectively.3)Testing the attraction effect of four most attractive volatiles mixture formulation at the ratio of 1:1:1:1:6 with three solvents i.e.paraffin oil,torula yeast and protein bait at three adult physiological stages of three Bactrocera spp.The average lure rate of B.tau up to 60.89%to female while 56.44%to male,with torula yeast and protein bait were showed average attraction rate up to 92.95%to female while 87.33%to male.B.cucurbitae with paraffin oil showed attraction rate up to 61.78%to female while 54.89%to male,with torula yeast and protein bait were showed average attraction rate up to 93.55%to female while 89.44%to male.B.dorsalis showed attraction rate up to 61.95%to female while 57.33%to male,with torula yeast and protein bait were showed average attraction rate up to 86.89%to female while 82.56%to male at indoor and outdoor conditions respectively.The results exhibited synergistic effects while protein bait and torula yeast showed highest synergistic effect as compared to the paraffin oil after mixing with four attractive volatiles while,female showed higher attraction response than male and the results further revealed that indoor experiment were consistent with outdoor experiment at three adult physiological stages to male and female of Bactrocera spp.4)On the basis of above study,the best proportion of four volatiles were mixed with paraffin oil,torula yeast and protein bait.The best four attractive volatiles to B.tau were 3-methyl-1-butanol,octyl acetate,ethyl caprylate and phenethyl alcohol,during three physiological stage,the optimal proportion of four attractive volatiles with paraffin oil were 25:15:25:20,with torula yeast were 20:20:25:15,with protein bait were 25:15:25:20.The best four attractive volatiles to B.cucurbitae were 3-methyl-1-butanol,phenethyl acetate,ethyl caprylate and phenethyl alcohol with paraffin oil were 5:10:10:10,while,with torula yeast were 15:10:5:15,with protein bait were 15:15:10:5.The optimal proportion of four attractive volatiles to B.dorsalis were phenethyl actate,octyl acetate,ethyl caprylate and phenethyl alcohol with paraffin oil were 25:25:20:15,with torula yeast were 15:15:15:15 and with protein bait were 25:20:15:25.5)The effect of protein baits and volatile compounds on the odorant binding protein genes expression profiling in the antennae of B.dorsalis.The results revealed that OBP1 during post-mating,OBP2 during all tested stages were largely expressed in response to protein bait and torula yeast.OBP1-OBP7 during pre-mating and post-oviposition while OBP5,OBP6 and OBP10 during post-mating stage were highly expressed in response to(MIX)treatment.OBP7 during pre-mating and post-mating while OBP5 during post-mating and OBP4,OBP5,OBP7 and OBP9 during post-oviposition stage were highly expressed to phenylethyl acetate(PA).OBP5,OBP1 were abundantly expressed to ethyl caprylate(EC)during post-mating and post-oviposition stage respectively.OBP3,OBP5 during pre-mating,OBP5,OBP6,OBP8,OBP10 during post-mating and OBP10 at post-oviposition stage were highly expressed in response to irradiation(N)treatment.