Study On The Attractiveness Of Various Rice Plant Volatiles And Odor Substances On Anagrus Nilaparvatae Pang Et Wang

With the development of chemical ecology,the behavior of plant volatiles in controlling pests and natural enemies is receiving more and more attention.Using semiochemical-based biological control methods to control pests with natural enemies has become the focus of research.Anagrus nilaparvatae Pang et Wang is the major parasitoid natural enemy in the oviposition stage of the rice planthopper,which has significant effect on the control of the number of planthoppers in rice fields with the large population,strong reproductive capacity and wide ecological niche.In this paper,a variety of rice volatiles and odor substances were selected to study the attractiveness to A.nilaparvatae.The details are as follows:The behavioral responses of A.nilaparvatae to 15 individual rice plant volatiles(1-octen-3-ol,1-nonanol,2-heptanol,leaf alcohol,6-methyl-5-hepten-2-one,β-ionone,2-octanone,geranyl acetone,β-caryophyllene,ocimene,methyl eugenol,isoeugenol,indole,1-octanal and cis-3-hexenyl acetate)were tested in Y-tube olfactometer.The research results showed that A.nilaparvatae female adults were significantly attracted by 10 mg/L of 1-nonanol,1 mg/L of 2-heptanol(alcohols),0.1 mg/L of geranyl acetone(ketones),and 0.01 mg/L of β-caryophyllene(alkenes).Eleven mixtures composed of behavior-active compounds were also tested in Y-tube olfactometer.The results showed that geranyl acetone(0.1 mg/L)+ 2-heptanol(1 mg/L),geranyl acetone(0.1 mg/L)+β-caryophyllene(0.01 mg/L),2-heptanol(1 mg/L)+ 1-nonanol(10 mg/L),and 2-heptanol(1 mg/L)+ 1-nonanol(10 mg/L)+ β-caryophyllene(0.01 mg/L)attracted A.nilaparvatae significantly.Eight species of flowering plants(japanese youngia,annual fleabane,oxalis,ruccola salad,purpus privet,pyracantha,cole and leptosin)were selected to test the behavioral responses of A.nilaparvatae to the flowers in flowering period.According to the results of biological assay,A.nilaparvatae showed significant preference to annual fleabane(weed),purpus privet(shrub)and leptosin(ornamental plants).Eignt species of main honey(linden honey,acacia honey,clover honey,jujube honey,thorns honey,longan honey,codonopsis honey and vetch honey)in our country were used in the olfactory test of A.nilaparvatae.The results showed that the concentration of 1% of the acacia honey,10% of the clover honey and the concentration of 0.1 % and 1% of the vetch honey had a significant effect on the behavior of A.nilaparvatae.The above results showed that volatiles released from the host plant,flowering plants and honey have specific components to attract A.nilaparvatae,these components can be used as attractants to trap natural enemies for biological control.The research could provide theoretical basis for promotion of information compounds in the field.