Effects Of Lavender And Its Essential Oil On Biological Activity And Behavior Of Colorado Potato Beetle

Colorado potato beetle is one of the major quarantine pests in China,which has seriously affected the development of potato industry in China.In recent years,due to the long-term use of chemical pesticides,Colorado potato beetle resistance has increased,making it more difficult to control.At present,because of the diverse modes of action of plant essential oils in the control of targeted pests,they play an important role in the control of agricultural pests.Lavender,as one of the important fragrant plants in China,its essential oils also have good control effects.this paper studied the prevention and control effects of different treatment measures of lavender and its essential oil on Colorado potato beetle,and the main research results are as follows:Different concentrations of lavender essential oil had good antifeeding and stomach toxicity effects on Colorado potato beetle larvae.In terms of non-selective antifeeding,the antifeeding effect at 10μl/m L concentration was significantly higher than that at other concentrations,and the antifeeding ability at each concentration decreased gradually with the prolongation of time.At the concentration of 10μl/m L for 12 h,the highest antifeeding rate was 76.77%.At the concentration of 1.11μl/m L for 72 h,the lowest antifeeding rate was11.48%.The corrected mortality rate of the second and third instar larvae of potato beetle at 10μl/m L was significantly higher than that of the other treatments,and the mortality rate at each concentration was significantly higher than that of the control.Lavender essential oil significantly affected the growth and development of the 2nd and 3rd instar larvae of Colorado potato beetle at the concentration of 10μl/m L at 12 h.For Colorado potato beetle,at the same time,with the increase of concentration,the repellent effect gradually strengthened,at 2 h,50μl/m L,the best repellent effect was gradeⅣ,at 6 h,1.56μl/m L,the weakest repellent effect was gradeⅠ.The emergence rate and pupation rate of Colorado potato beetle were significantly decreased when the lavender residue was mixed with flower soil.With the increase of lavender residue ratio,the pupation rate and pupation rate of Colorado potato beetle were gradually decreased,and there was no effect on potato beetle entering the soil.According to the above research,lavender and essential oil have certain application value in the control of Colorado potato beetle.Treatment of Colorado potato plants with lavender essential oil had certain effects on the occurrence time and frequency of various behavior types of Colorado potato beetle adults.Under the time of behavior type,the total time of behavior type of male Colorado potato beetle after spraying the whole plant with lavender essential oil was1424.1 s,which was significantly lower than other treatments.For both male and female Colorado potato beetles,the feeding time of spraying essential oil on the whole plant and the upper part of the plant was significantly lower than CK and CK₁.Under a number of behaviors,the entire plant spraying lavender essential oil,the Colorado potato beetle behavior walk total number,plant number,feeding times were significantly lower than that of upper plant spraying oil,CK and CK₁,return number significantly higher than that of upper plant spraying oil on the ground,CK and CK₁,the Colorado potato beetle,female insect behavior have lowest total number of 6.5 times.The distribution of Colorado potato beetle on the plant was affected by spraying essential oil on the upper part of the plant and the whole plant,showing a significant repellent effect.