摘要
通过频次分布和聚集度指数的测定,以及m*-m回归和Taylor幂法则分析,研究西兰花菌核病病株田间空间分格局及其抽样技术。结果表明,西兰花菌核病病株田间分布趋向于聚集分布。被测田块都不符合二项分布,而同时符合核心分布;各田块的西兰花菌核病I指数>0,M*/M指标>1,Ca指数>0,扩散系数C>1,K指数>0,m*-m回归分析表明病株空间分布的基本成分是个体群,病株个体间相互吸引,病株在大田中存在明显的发病中心,个体群在田间呈随机分布格局,即分布的基本成分发病中心之间趋于随机分布,而个体群内的个体与核心分布相吻合。Taylor幂法则分析表明,西兰花菌核病病株个体的空间格局随着病株密度的提高越趋聚集分布。随着病情指数的增加,所需抽样数递减。序贯抽样模型为T0(N)=1.5N±2.8615N,调查株数N株时,若累计病情指数超过上界可定为防治对象田,若累计病情指数未达到下界时,可定为不防治田。病情指数15%,所需抽样数为90。
This paper studied the spatial distribution pattern and sampling technique for the fungal Sclerotinia sderotiorum, in the broccoli field. The tests of frequency distributions indicated that the all samples were not fitted to the evenness distribution, but to the neyman, The analyses of aggregation indexes showed that Lloyd＇s index of mean crowding （ m^＊） ranged between 1. 397 and 2.223. Cole＇s index （ I ） of dispersion was more than 0, David and moore＇s index （ m^＊/ m） more than 1, Kuno index （Ca） more than 0, dispersion index （C） more than 1, negative binomial index （K） more than 0, which suggesting aggregate or contagious distributions of the tested samples. The distribution pattern of the infected plant individuals had the tendency of gathering with the density of broccoli increased. The sampling numbers decreased with increasing the pathogen index. The sampling numbers were 90 plants when the incidence was 15% and the sampling numbers were 54 plants when the incidence was 25%.
出处
《浙江农业学报》
CSCD
2006年第2期63-66,共4页
Acta Agriculturae Zhejiangensis
基金
浙江省重大招标项目(2004C12001
2003C122003)
关键词
西兰花
菌核病
空间分布格局
抽样技术
Brassica oleracea L. var. italica Planch
Sclerotinia sclerotiorum
spatial distribution pattern
sampling technique
