Study On Sustained Release From Mating Disruption Meso-dispensers Of Grapholita Molesta

Grapholita molesta（Busck）（Lepidoptera,Tortricidae）is a destructive pest,which seriously harm fruit.Biological control has been widely used in the prevention and treatment of G.molesta because of the characteristics of being safety,effectiveness and environmental friendliness.Mating disruption technology is an indispensable part of biological control.At present,the research about mating disruption products mainly focused on the formulation ratio and field control.But,there are some problems in the field application process such as large dosage,time-consuming and laborious layout.Therefore,it is of great significance to develop mating disruption meso-dispensers with good effect and a number of layouts for the highly effective control of G.molesta.In this paper,different thickness of mating disruption meso-dispensers were screened in the field at different release intervals,and the indoor release rate of mating disruption dispensers was determined.The main findings are as follows:1.G.molesta in peach orchard was controlled by mating disruption meso-dispensers.The experimental results show that the rate of mating disruption with a thickness of A can achieve a higher at a distance of 20 m,by comparing the rate of mating disruption of the mating disruption dispensers of different thicknesses（A,B,C and D）at different intervals（10,20,and 30 m）.2.By gas chromatography analysis,the standard curve of（Z）-8-dodecenyl acetate（Z8-12: Ac）was obtained as y = 16.918 x + 7.1694（r² = 0.9997）.The release rate of pheromone was determined by residual quantity method.The results showed that the release rate of pheromone in the mating disruption mesodispensers decreased with time,and the retention rate changes exponentially with time.The retention fitting curve of low,medium and high contents of mating disruption meso-dispensers were y = 1.00008e^-0.29243x（r² = 0.99996）,y = 1.00558e^-0.11029x（r² = 0.99099）,y = 1.03164e^-0.07563x（r² = 0.99077）.The release rate of pheromone in mating disruption wire fluctuated with time,and the retention rate was linear with time.The fitting curve was y =-0.00327 x + 0.95421（r² = 0.90683）.3.The release rate of（Z）-8-dodecenyl acetate（Z8-12: Ac）was determined by weighing method in three kinds of sealing methods.The results showed that the release rate of heat-sealed mating disruption meso-dispensers was longer than that of normal and vacuum sealing,and the heat-sealed mating disruption meso-dispensers could improve the release duration of pheromone.In summary,this article has screened out the optimal thickness of mating disruption dispensers as A and the optimal delivery distance of 20 m through 2 years of field and indoor experiments.At the same time,the relationship between the release rate of the mating disruption dispensers and the application time was clarified,which provided a theoretical basis for the research and development of the sparse mating disruption dispensers and the development of application technology,and optimized the application of pheromones to prevent and control the mating disruption application measures.