摘要
以病样方率、平均样方病株数、扩散系数和聚块性指标等多数分析了番木瓜环斑病病株的田间分布类型，并利用模糊聚类方法初步探讨了此病的流行特征。结果表明病株在田间的分布随着时间的发展而变化。在流行初期，病株呈随机分布，随后呈聚集分布，到后期则趋于均匀分布。
Analysis of the spatial distribution of Papaya ringspot disease showed that thedistribution pattem of the diseased plants in the field changed with time. At the be-ginning of the disease development,a random pattern was observed,then a clusteringtype of distribution,and an even pattern at the last stage. Based on Fuzzy clusteringmethod, the characteristics of disease spread dynamics in different time were studied.Atthe early epidemic stage when virus-carried alate aphids immigrated into the papayafield,the disease began to develop. In this period,the development of the disease wasmainly the increase of the diseased spots.Later on,after a great amount of vectorsimmigrating into the field,a rapid increase of diseased spots was found to spread allover the field,a rapid increase of diseased spots was found to spread all over thefield.Meanwhile there was a rapid increase in number of the diseased plants.At thelast epidemic stage,the diseased plants increased in number slowly,and a hundredpercent of plants in the field was infected by the disease.
出处
《华南农业大学学报》
CAS
CSCD
1995年第4期27-31,共5页
Journal of South China Agricultural University
