| The cheese mite, Tyrophagusputrescentiae(Schrank) belonging to the family Acaridae is an important pest on stored products and the mushroom in the world. It is also a major pathognomonic pathogen of dermatitis, some internal disease and allergy of human being. It is widely distributed and can feed on many different agricultural products. That minute individual is so easy to infect and contaminate crops and foodstuff that it results in serious loss or harm to agricultural products and people's health.The effect of temperature on the development and growth of T. putrescentiae were conducted. The sensitive baselines of 15 pesticides were initially set up. The developmental dynamic and resistant mechanism of T. putrescentiae to phosphine were studied through selectively raising in laboratory. Based on the studies, the methods of controlling T.putrescentiae, the criterion of resistance detection of T. putrescentiae to phosphine and the countermeasure of controlling development of its pesticide resistance were discussed. The results could be summarized as follows:1. Developmental periods of all phases of T. putrescentiae besides the phase of eggs and prophase were radically shorten as temperature is raising. Developmental periods of whole generation was 65.92 days at 12. 5癈 and 10.99 days at 30.0癈. The regressive relationship of developmental period, developmental rate and temperature are: the phaseof eggs, D= 23. 2750-0. 7759T (R=-0. 8917*K V =-0. 1864 +0.02087 (R= 0. 9237*) ;the phase of larva, D=17. 8350-0. 55157(R=-0. 8741*), V=0. 0869 +0.01477 (R=0. 9290*); the phase of protonymph, D= 12.9850 - 0.40807 (R=-0. 9231*), V= -0. 2321+0. 02677(R=0. 9836**) ;the phase of deutonymph, D= 24. 1450- 0. 82047(R=-0. 8242*), V= -0. 2315+0. 02357(R=0. 9643**) ; the whole generation, D= 85. 7550-2. 78417(R=-0. 8581*) N V= -0. 0343+0. 00437 (R=0. 9721**).2. High or low temperature was harmful to oviposition but had no evident effect on hatching of eggs. The most suitable temperature for existing of larva was 20℃. It had no evident effect on existing of protonymph of temperature, but the survival rate of deutonymph radically decreased when temperature was from 12. 5℃ to 30℃.3. The threshold temperatures for the development of eggs, larva, protonymph and deutonymph were (10.47 ± 2.31) ℃, (8.09 ± 2.36) ℃, (9.09 ± 1.16) ℃ and (10.59 ± 1.73) ℃ respectively. The developmental effective accumulated temperature for eggs, larva, protonymph and deutonymph were 41.79, 58.06, 36.27, and 39.53 day-degrees, respectively. It needed 221. 72 day-degrees for completing one generation above 8. 38℃. According to this, 7. putrescentiae could complete 18-19 generation in one year in Fuzhou.4. The results of toxicity measurement of 15 insecticides to 7. putrescentiae showed that these insecticides could control 7. putrescentiae female adults, but no effect on eggs. The most effective insecticide was abamectin. Its LC50 was 0.2568 mg - L-1. But the least effective one was dichlorovos , whose LC50 was 320. 4793 mg ?L-1.5. The suffocating toxicity of phosphine to the sensitive population of 7. putrescentiae was 28.4 minute. The resistance level of 7. putrescentiae had reAChEd 4.75-fold to phosphine after being treated 16 generations in the laboratory. The regressive curve equation between LT50 of resistant generations and treated generations was y=13. 2021+7.4088x(R=0.9841).6. Protein content was different in different 7. putrescentiaegenerations. Protein content of resistant generations radically increased along with the level of resistance development. The regressive curve equation between protein content and resistant generations was y=0. 3953+0. 0909x(R=0.9515).7. One of the mechanism of resistance to phophine was that the activities of CarE and AChE T. putrescentiaehad changed. The activities of CarE and AChE radically boosted up along with the resistance level development. The regressive curve equation between the activities of CarE and AChE of resistant generations and the level of resistan...
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