甜瓜霜霉病斑在叶片上的空间分布格局及抽样技术  

Spatial distribution pattern and sampling technologies of melon leaf downy mildew disease spots on the blades

作　　者：段显德[1] 董荣春[1] 王硕[2] 杨信东[2] 

机构地区：[1]辽东学院农学院,辽宁丹东118003 [2]吉林农业大学农学院,吉林长春130118

出　　处：《东北师大学报（自然科学版）》2015年第4期123-128,共6页Journal of Northeast Normal University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(30600003);辽东学院博士启动基金资助项目(891101);丹东市科技发展计划项目(20130726)

摘　　要：通过扩散系数和聚集指数两个空间分布型指标及平均拥挤度和均值的回归关系,研究了甜瓜霜霉病斑在叶片上的空间分布格局.结果表明:甜瓜霜霉病初侵染的病斑在叶片上呈现随机分布,再侵染的病斑呈现聚集分布.随着病斑数的增加,所需抽样数递减.序贯抽样模型为T(高/低)=0.1 N±0.682 N1/2.调查叶片为N片时,若累计病斑数超过上限则可确定为需防治田圃;未达到下限时,可确定为不需防治田圃;如在上下限之间,则应继续调查.采用集聚指数和均值数据进行相关分析,判断甜瓜霜霉病病斑在叶片上的集聚程度与病害发生程度间的相关性,可以取代Taylor幂法则等其他判断聚集强度与种群密度相关性的方法.Spatial distribution pattern in leaves of disease spots of melon downy mildew was studied in this paper.The study was conducted through the two spatial distribution pattern indexes of dispersion coefficient and aggregation index as well as the regression relationship of evenness aggregation and mean value.The results showed that the downy mildew spots were distributed randomly in melon leaves after first infection,while it exhibited an aggregated distribution after second infection.With the increase of disease spots,the sampling number needed gradually decreased.sequential sampling model is T（high/low）=0.1 N ±0.682 N^1/2,When the number of leaves is N,if the field of the accumulated disease spots beyond the upper threshold is considered the field that should be prevented and treated,if it is under the lower threshold,the one unnecessary to be prevented and treated,if it is between the lower and upper threshold,a continuous survey is due.Used the relativity method based on aggregation index and average data to analyze and judge aggregation degree of disease spots of melon downy mildew in leaves and disease severity,which can completely replace Taylor power law or other relativity methods to judge aggregation intensity and population density.

关 键 词：甜瓜霜霉病 空间分布格局 理论抽样数 序贯抽样检索表 

分 类 号：S432.1[农业科学—植物病理学]