Effect Of E-β-farnesene(EBF) On Behavior And Wing Differentiation Of Rhopalosphum Maidis Fitch

Aphids are important pests in agriculture and forestry which have brought about serious losses every year. In this thesis, the life table of the laboratory population of Rhopalosiphum maidis Fitch was set up, the behavioral response to (E)-β-farnesene (EBF) at different life stages was observed and the effect of parental density experience as well as EBF on wing differentiation of R. maidis was studied. The main results were as follows.1 The life table of laboratory population of Rhopalosiphum maidis FitchThe life table of laboratory population of R. maidis at the temperature of 23±1℃and relative humidity (RH) of 75±5% was set up. The results were: rm=0.341,λ=1.406, R0=24.119, T=9.335 and t=2.033, respectively.2 Behavioral response of Rhopalosiphum maidis Fitch to (E)-β-farnesene (EBF)Comparatively, the 1st instar nymphs were most sensitive to EBF at 1% (V/V) for the moving ratio reached 56.0% 3 min after exposure; the 2nd instar nymphs were most sensitive to EBF at 0.1% and 1% and the moving ratios were 52.1% and 51.6%, respectively and the 3rd and 4th instar nymphs and adults were all sensitive to EBF at the concentration ranged from 0.001% to 1% and the moving ratio was ranged from 39.5% to 52.4%。3 Effect of parental density experience of Rhopalosiphum maidis Fitch on wing differentiation of next generationThe wing type ratio was from 26.97% to 34.44% when R. maidis were reared at the density from 1 individual per plant to 30 individuals per plant. When the wingless R. maidis were reared at the density of 10, 20, 30, 40 and 50 individuals per plant, respectively, the wing type ratios of the nxet generation were 53.09%, 67.50%, 77.38%, 80.50% and 82.96%, respectively. Also, the parental density experience of R. maidis was found to affect the wing differentiation of the offspring.4 Effect of (E)-β-farnesene (EBF) on wing differentiaon of offspring of Rhopalosiphum maidis FitchThe wing type ratio of the offspring of Rhopalosiphum maidis Fitch was found to increase with EBF exposure frequency. When EBF exposure frequency was set at once, 3 times and 5 times a day, the wing type ratios of the offspring, which were reared at the density of 10 individuals per plant, were 54.00%, 68.00% and 81.00%, respectively and they were sinificantly higher than those in controls which were 32.00%, 25.00% and 32.00%, respectively.