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春小麦蚜虫空间分布型及抽样技术研究(英文)
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作者 任月萍 贺达汉 《Plant Diseases and Pests》 CAS 2010年第4期39-41,50,共4页
[ Objective] The aim was to study the spatial distribution pattern and field sampling method of aphid population in spring wheat. [ Method] The aphid quantity in tested wheat field was calculated, the field distributi... [ Objective] The aim was to study the spatial distribution pattern and field sampling method of aphid population in spring wheat. [ Method] The aphid quantity in tested wheat field was calculated, the field distribution pattern of wheat aphid was calculated by using aggregated index method, the aggregated reason was analyzed and the field theoretical sampling number was ascertained. [ Result] The wheat aphid population showed aggregation distribution and negative binomial distribution, and such aggregation distribution was induced by interaction of its behavior and environmental factors. The field theoretical sampling number of wheat aphid was related to sample variance and permissible error; the less the sam- ple variance [ S^2 ) was, the less the permissible error [ d') was, the bigger the theoretical sampling number without replacement was; when the initial population numbers were different, the theoretical sampling numbers were also different; after the permissible error being set, the bigger the sample variance ( S^2 ) was, the bigger the theoretical sampling number was. [ Conclusion] This study supplied scientific basis for prediction and field control of wheat aphid. 展开更多
关键词 Wheat aphid Spatial distribution pattem Theoretical sampling number
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