| The paper studied the species of the thrips in Yangzhou and investigated the thrips in eggplant ,pepper and cucumber. It showed that the dominant species of thrips in the vegetables was Thrips palmi Karny through making microsection to observe in microscope and photographing living bodies in Electronic microscope to discriminate the morphological characteristics of different thrips .The population fluctuation of Thrips palmi was investigated in eggplant , pepper and cucumber from November , 2001 to December , 2002. It showed that there were three peaks of population in late July , mid-August and early September . At the same period , the amount of Thrips palmi in cucumber was the highest . It was subordinate in eggplant and pepper . The Efficiency of three rearing ways were observed on surviving rate of each instar of Thrips palmi nymphs. The experiment showed that surviving rate was the highest when they were reared by the way of microscope concave slides. The total surviving rate from nymph to adult was 59.2%. The ways of using potted eggplant and of water island were subordinate. The efficiency was 42.4% and 20.0% respectively.Aggregate indexes and Iwao-law were used to test the spatial pattern of adult and nymph of Thrips palmi in eggplant fields . Each index showed that the spatial pattern of Thrips palmi in eggplant field was aggregate. The reason was their own behavior or the effect of the combination of the behavior and environmental disparate nature.Different sampling methods were compared in eleven eggplant fields. That was to compare the result of using sampling method of "Double-diagonal" , "Five-spot" , "Z-shape" , "Checkerboard-shape" with that of whole-plantssampling. It was showed that the efficiency of Checkerboard-shape way was the best and it can show the true amount of Thripspalmi in the fields objectively .Potted eggplant and microscope concave slides were combined to rear Thrips palmi from early April to early October in order to observe the influence of different average temperature under natural temperature on growth and development of Thripspalmi. Then Enzyme Reaction Kinetic Model was used to simulate the relationships between the developmental rate of Thrips palmi and temperature and the direct optimum method was used to estimate the thresholds of development and thermal constants in different development stages of Thrips palmi .The developmental thresholds of Egg, Nymph (1st intar to 2nd instar),Nymph(3rd instar to 4th instar) and the whole generation were 11.49?, 10.51 , 8.16 , 10.80 , respectively, and the thermal constants were 58.33DD, 60.36DD, 101.67DD, 218,17DD respectively. The model was also fitted for the relationship between surviving rates of different stages of Thrips palmi and temperature. The theoretic optimum temperatures of low-instar larvae and high-instar larvae were 24.2 ,24.7 respectively according to the data of experiment population life table under different temperatures . In addition , the experiment population life table was drawn in different hosts of eggplant, pepper and cucumber . The indexes of population increase in these hosts were 23.6,17.1 and 32.4 respectively. So it can be concluded that the cucumber was the mostbeneficial to the growth of Thripspalmi population .The methods of forecasting for the population of Thripspalmi were explored in this paper . It showed that bluish color was the most attractive to Thrips palmi, The attracting amount of Thrips palmi in the range of color wave length from 4700 to 4750A was the highest, so bluish sticky card can be used to attract the adults and get the fluctuation dynamic of Thrips palmi adults . Moreover , Thrips palmi was always found to fall onto the soil to pupate as high-instar larva . So thefluctuation dynamic for the various amount of pupae on the soil surface can be got through investigating regularly . The fluctuation dynamic of adults , that of pupae and the through-year fluctuation dynamic of larvae were compared, which showed there was significant correlation between the...
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