Quarantine Fumigation Technology Of Ethyl Formate And Phosphine On Jack Bell's Mealybug

Jack Bell S's scale has been intercepted at our quarantine port several times.In order to prevent the spread of this species of mealy bug in Chinese mainland,quarantine and elimination measures should be strengthened to study new ways of removing pests.Ethyl formate and phosphine as new fumigants have broad application prospects.In this paper,based on the establishment of the experimental population of mealybug,we used ethyl formate and phosphine as fumigants and combined with cold treatment to determine the toxicity of the two fumigants on different ages of mealybug,and to determine the effect of the two fumigants on the quality of imported fruit.The results showed that:1.In this paper,the biological characteristics of mealybug Jack bell were studied.Temperature 26±1?,humidity 80±5%of the feeding environment,An experimental population of mealybug Jack bell was established on germinated potatoes.It can be divided into five developmental stages:egg,first instar nymph,second instar nymph,third instar nymph and female adult.2.The ethyl formate fumigation technology of Pitaya carrying pink scale was established.The results of tolerance to ethyl formate fumigation were as follows:egg>female adult>old nymph>young nymph.After fumigation with ethyl formate at 20?for 4 h,the mortality of eggs and female adults reached the probability value of 9,and the concentration of ethyl formate required was 109.76 g/m~3and 78 g/m~3;The mortality of eggs treated at 5?for 12 hours or more and at 10?for 72 hours or more was 100%.The results showed that ethyl formate fumigation had no significant effect internal quality of Pitaya;However,fumigation with ethyl formate of more than 60 g/m~3 for 4 h caused surface damage to pitaya.Therefore,it is suggested to use 20 g/m~3at 20?Fumigation with ethyl formate for 4 hours or more,combined with 5?cold treatment for 12 hours or 10?cold treatment for 48 hours,were used as the quarantine treatment technical indexes of Pitaya.3.The phosphine fumigation technology of Pitaya carrying powdery scale was established.The results of tolerance to phosphine fumigation were as follows:egg>female adult>old nymph>young nymph.When phosphine was fumigated at 20?for4 h,the mortality rate of eggs and female adults reached the probability value of 9,and the required phosphine concentrations were 2645.75ppm and 1364.96ppm,respectively;The mortality of eggs treated at 5?for 12 hours or more and at 10?for 24 hours or more was 100%.The results showed that phosphine had no significant effect internal quality of Pitaya.Phosphine fumigation can stimulate the respiration rate of Pitaya in a short time,and gradually return to normal with the extension of time,and the whole process does not affect the quality and commodity value of the fruit.It is suggested that fumigation with 1500ppm phosphine at 20?for 4 h,combined with cold treatment at5?for 12 h or cold treatment at 10?for 24 h can be used as the technical index for quarantine treatment of P.jackbell.4.At 5?,the mortality of each insect state reached 100%after fumigation with800ppm and above phosphine for 2 hours and above,and there was no significant effect quality of longan,which would not affect the quality and commercial value of fruit.