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利用模糊聚类分析方法对小白菜花叶病介体蚜虫种群增长和病害流行的时空动态分别进行分析,并对介体种群增长和病害流行时空动态进行概述。田外带毒介体扩散迁入,花叶病开始发生,在病害流行初期,由于介体在本田内未建立种群,来自田外的带毒有翅蚜虫在田内随机扩散,导致病害的空间扩展迅速,病样方率逐渐上升,病株率伴随上升,每病样方多为1株病株;在病害流行前期,随着介体的进一步迁入和定殖,病害的空间扩展加快,病样方率迅速上升,样方内病株数量增加,病害严重度上升缓慢;在病害流行中期,田内介体种群密度上升,有翅介体在田内大量扩散,导致病株遍及全田,病样方率接近饱和,病害的增长以病株率上升为主;在病害流行后期,病株率接近饱和,严重度迅速上升,然后超于平缓。
The temporal and spatial dynamics of aphid population growth and disease epidemic in Brassica campestris were analyzed by fuzzy clustering analysis. The spatial and temporal dynamics of the population growth and disease epidemic were summarized. In the early days of disease, vector-winged aphids from outside of the field were randomly spread in the field due to the mediator’s lack of population in Honda, resulting in the expansion of disease space Rapidly, the rate of disease-like quadrats increased gradually, and the rate of diseased plants increased with the number of isolates in each disease was mostly 1 strain. In the early stage of disease prematurity, with the further migration and colonization of mediators, the space expansion of disease accelerated. The quadrats rate increased rapidly, the number of diseased plants in the quadrats increased, and the severity of the diseases increased slowly. In the mid-term of disease epidemic, the population density of the mesophytes increased and the abundance of the finned mediators spread in the fields, The rate of disease is close to saturation, and the increase of disease is mainly caused by the rate of disease. At the later stage of the disease epidemic, the rate of diseased plants is close to saturation, and the severity rises rapidly and then exceeds the flat rate.