Study Of Aloe Extracts On The Repellent Activity Of Oriental Fruit Fly(Bactrocera Dorsalis Hendel)

Oriental fruit fly,Bactrocera dorsalis(Hendel)is a serious international quarantine pest,which occurs on a wide range of fruit crops and vegetables.The main damage is the feeding of maggots(larvae)inside fruits.So that the fruit surface left spawning traces and interal rot,resulting in serious economic losses of fruit and vegetable industry.Todetermine the effects of non-host plant on the repellent activity and oviposition behavior of oriental fruit fly,and to explore the effect of the combination of liquid membrane and repellent to control the o riental fruit fly.The repellentactivity ofnon-host plantAloe vera L.against oriental fruit fly was studied.By the different solvent screen outthe higer repellent activity of extract,and the o lfactory behavior of this extract on the oriental fruit fly was studied.The effects of dose extract and oviposition behavior on the oriental fruit fly were studied.The extract of the preparation of dosage forms were studied preliminarily by film-forming and drug release and to investigate the effects of oviposition on the oriental fruit fly by liquid membrane bound extract.The results obtained might be summarized as follows.(1)Screeing of the repellent oviposition activity of different solvent extracts: The methanol,acetone,ethylacetate,dichloromethane and petroleumextracts of non-host plant Aloe vera L.were repellent oviposition of oriental fruit fly at the concentration of 1 mg/mL,but the acetone extract had the strongest repellent.The oviposition repellent rate was 85.41 % at 24 h in non-selective test and the oviposition repellent rate was 60.17 % at 24 h in selective test.(2)The olfactory behavior response of aloe acetone extract odor on the oriental fruit fly: The repellent effect of acetone extract of Aloe vera L.on the oriental fruit fly adults were studied by Y-type olfactometer.It was found that the male and female had a strong repellent effect,the female's repellent rate was 71.11 % and the male's repellent rate was 84.17 %.The results showed that the EAG of the female was 0.388 mv and the male was 0.257 mv.(3)The dose effect of repellent oviposition of aloe acetone extract against oriental fruit fly: The effects of different concentration of acetone extract of Aloe vera L.on the oviposition repellent effect of the host plant guava were significantly different on theoriental fruit fly.With the increase of the concentration of treat,the oviposition repellent effect was stronger.When the concentration was 10 mg/mL,the oviposition repellent rate was 89.43 % at 24 h in non-selective test and the oviposition repellent rate was 68.81 % at 24 h in selective test.(4)Persistence study: The oviposition repellent effect of the persistent period of Control acetone extract of Aloe vera L.lasted 6 days,when theconcentration was 10 mg/mL.Three days before the treatment,the repellent effect was stronger and the oviposition repellent rate was more than 60 %.(5)Interference to the oviposition behavior of aloe acetone extract on the oriental fruit fly: O viposition behavior of o riental fruit fly influenced by acetone extract of Aloe vera L.was observed.When female B.dorsalis encounted guava host treated with acetone extract of Aloe vera L.,the behavior was changed.The study found that the visiting frequency,the attempt oviposition frequency and the actual oviposition frequency were significantly less than the control.The total visiting time and attempt oviposition time were significantly lower than the control.The time of first finding was significantly longer than the control.The number of egg and spawning hole were also significantly less than the control.(6)The repellent effect of liquid membrane agent and combined with repellent on the oriental fruiut fly: The Aloe gel coated with guava had certainly repressive effect on theoriental fruit fly.Different alcoholysis degree of pva coated with guava could reduce the amount of egg on the theoriental fruit fly,which pva-224 had the best oviposition repellent effect.Combined pva-224 film with repellent could enhance the efficacy of repellent.The properties of pva-224 film were tested and their microstructures were observed by scanning electron microscopy.