Study On Mechanism Of Pushing Or Pulling Empoasca Vitis (G(?)the) By Volatiles From Seven Species Of Host And Non-host Plants

Tea green leafhopper Empoasca vitis (G the) is the dominant species pestin tea plantations.Traditional control methods for prevention and treatment of theleafhopper have the limited effect.For a long time,chemical control has the goodeffect,but using the chemical pesticides frequently has brought a series of troublesand the production of tea also does not meet the requirements.Thus it is necessary tofind a green security way to control the leafhopper.There are a variety of herbaceous and woody plants in the tea plantationsecosystem.In this paper, the behavioural bioassay on tea green leafhopper wasexecuted by Y-tube olfactometer with the tender part of Rosmarinus officinalis L．,Mentha haplocalyx Briq．, Pelargonium odoratissimum (L.) L Hér．, MelissaOfficinalis L．, Tagetes erecta L．, Lavandula angustifolia M．and Camellia sinensis(L．) O．Kuntze being odor source.We delve into the volatiles of Rosmarinusofficinalis L．and Mentha haplocalyx Briq．on the regulative effect of leafhopper,carryon the field test and the effect is ideal.The results are as follows:1. Potential effect of volatiles from tender Rosmarinus officinalis L．shoots withfresh leaves on the tea green leafhopper behavior was assayed using Y-tubeolfactometer against the clear air as CK. The result showed that the numbers of thetea green leafhoppers to choose the Rosmarinus officinalis L．odor source firstlyincreased as the increase of odor dosage, and then reduced as further increase of theodor dosage in a parabolic curve-like relationship.46volatile compounds wereidentified from the Rosmarinus officinalis L．shoots with fresh leaves, including9alcohols,4ketones,4esters,1acid,18alkenes,7alkanes,1ether,1aldehyde and1phenol. Alcohol was the major volatile group with52.20%of the total amount.Eucalyptol,1S--pinene and Verbenone were three major components, accounting for42.54%,10.37%and6.82%of the total content, respectively. From the identifiedRosmarinus officinalis L．volatile compounds,25synthetic candidates representingall the major and some minor components were tested in Y-tube olfactometer inseveral dosages on the tea green leafhoppers against hexane as CK.10-2g/mL Camphor,10-4g/mL Caryophyllene,10-6g/mL and10-8g/mL-Phellandrene,10-4g/mL and10-10g/mL-Terpineol,10-10g/mL and10-8g/mL Eucalyptol displayed asignificant attraction to the leafhopper, whereas10-10g/mL β-Pinene showed asignificant repellency. Screening several active conponents to comprise variousblends at different ratio, loading blend on the rubber septa to become lures,subsequently attaching lure on the yellow jasmine board which was used to trap theleafhopper. The results were as following:①three component high dosage lureincluding10-2g/mL Camphor,10-2g/mL-Terpineol and10-2g/mL Caryophyllene at111ratio repelled the leafhopper;②five component appropriate dosage lureincluding10-2g/mL Camphor,10-4g/mL Caryophyllene,10-6g/mL(R)-(-)--Phellandrene,10-4g/mL-Terpineol and10-8g/mL Eucalyptol at11111ratio attracted the leafhopper intensely;③the half-life period of the fivecomponentlure could lengthened2-3days with the paraffin liquid being the additive;④the leafhopper activated during the dusk and daybreak, and the catches of theleafhopper from18:00to6:00accounted for over70%of the total amount.2. Potential effect of volatiles from tender Mentha haplocalyx Briq．shoots withfresh leaves on the tea green leafhopper behavior was assayed using Y-tubeolfactometer against the clear air as CK. The result showed that the numbers of thetea green leafhoppers to choose the Mentha haplocalyx Briq．odor source firstlyraised and then reduced in pace with odor source quality increasing, but whenbeyond a certain threshold,it present repellent effect.When Mentha haplocalyxBriq．at the dose of1g,the quantity difference of choosing mint odour and CK reachsignificant level.49components were identificated from the volatiles, including4alcohols,6ketones,2esters,30alkenes,4alkanes,1aldehyde and2others, with thecontent of ketones being the largest occupied83.85%of the total amount. The singlecomponent Pulegone, Cyclohexanone,5-methyl-2-(1-methylethyl)-cis-and Mentholpossessed the largest content, respectively occupied57.00%,23.25%and9.69%ofthe total amount. Selecting21compenents from the identificated volatiles and1gMentha haplocalyx Briq．volatiles as odor sources, using Y-tube olfactometer toperform bioassay, we found out that10-2g/mL cis-3-Hexenyl acetate、10-4g/mL3-Octanone、10-4g/mL Caryophyllene、10-6g/mL and10-8g/mL (R)-(-)--Phellandrene， and10-10g/mL γ-Terpinene、10-10g/mL and10-8g/mLEucalyptol disclosed significant attracting activity, whereas10-10g/mL β-pineneshowed a significant repellency. Screening several active conponents to comprisevarious blends at different ratio, loading blend on the rubber septa to become lures,subsequently attaching lure on the white board which was used to trap the leafhopper.The results were as following:①six component lure including10-2g/mLcis-3-Hexenyl acetate、10-4g/mL3-Octanone、10-4g/mL Caryophyllene、10-6g/mL(R)-(-)--Phellandrene，10-10g/mL γ-Terpinene and10-8g/mL Eucalyptol at1:1:1:1:1:1ratio attracted the leafhopper intensely, and its control effect attained65%during the peak of the leafhopper；②the leafhopper activated during the dusk anddaybreak, and this period captured the largest number of the leafhopper;③thehalf-life period of the six component lure could lengthened2-3days with the paraffinliquid being the additive.3. The behavioural bioassay on tea green leafhopper was executed by Y-tubeolfactometer with the tender part of Pelargonium odoratissimum (L.) L’Hér．,Melissa Officinalis L．, Tagetes erecta L．, Lavandula angustifolia M．and Camelliasinensis (L．) O．Kuntze being odor source.The result showed that Pelargoniumodoratissimum (L.) L Hér． and Camellia sinensis (L．) O．Kuntze attracted theleafhopper,while Melissa Officinalis L．, Tagetes erecta L．and Lavandula angustifoliaM． had repellent effect. Using the Super Q as adsorbent, the routine air enterainmentwas used to collect the volatiles of Pelargonium odoratissimum (L.) L Hér． andMelissa Officinalis L．,then it was injected into GC-MS for qualitative andquantitative analysis.In conclusion, Rosmarinus officinalis L．and Mentha haplocalyx Briq．volatilescan control the behavior of tea green leafhopper effectively.The active components ofvolatile can be made to leafhopper bait.Or Rosmarinus officinalis L．and Menthahaplocalyx Briq．can be intercropped in tea plantations to attract the leafhopper. Thusexcept Camellia sinensis (L.) O．Kuntze,other plant volatiles also can attactleafhopper and have good effect. Pelargonium odoratissimum (L.) L Hér．, MelissaOfficinalis L．, Tagetes erecta L．and Lavandula angustifolia M．can also discussaccording to the research method of Rosmarinus officinalis L．and Mentha haplocalyx Briq．.It provides reference for screening tea trap plants.