| Echinothrips americanus Morgan was noted as a pest on greenhouse plant, and it has spread over most of the Europe and America, and also be reported in Japan and Southeast Asia. In this thesis, it was recorded as the first species of genus Echinothrips from China. The morphological characters and symptoms of E. americanus were described, the distribution and host range of the species in the central Shaanxi plain were investigated. We also analyzed the population of the species, researched effect of temperature on development of E. americanus and impact of reproduction mode in its population.The result indicated the host plants of E. americanus include Plumeria rubra, Aristolochia ovatifolia, Dregea volubilis, Medicago sativa, Zea mays, Phaseolus vulgaris, Prunus persicae and Nicotiana tabacum.The temperature between 19℃and 28℃is the optimum growth temperature for E. americanus. The species can not complete generation in 34℃or elevated temperatures. In the optimum temperature,the max spawning rate is 2.75eggs, per female, per day. Developmental threshold temperature for whole generation of E. americanus is 9.88±0.76℃, effective accumulated temperature for completing growth period is 391.78±20.57Day·℃. With the annual average temperature of Yangling area, author calculated the amount of annual generation is 5.7.The sex ratio of E. americanus pupolation in Yangling is 1:0.63(♀:♂). The population overwinter in greenhouse, rather than field.The offspring through parthenogenesis of E. americanus are all male. The average life and spawning rate are different in female individuals with different reproductive modes .
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