混播草坪锈病植株田间分布型测定及抽样技术分析

锈病（ＰｕｃｃｉｎｉａｃｒｏｎａｔａＣｏｒｄａ）是草坪草重要病害．通过对当地田间１６个混播草坪区的系统调查，并用聚集强度指标进行测定分析，其扩散系数Ｃ＞１．负二项Ｋ＞０，Ｃａｓｓｉｅ，Ｒ．Ｍ（１９６２）和Ｋｕｎｏ，Ｅ·（１９６８）指标Ｃ．＞０，Ｄａｖｉｄ和Ｍｏｏｒｓ（１９５４）丛生型指标１＞０，Ｌｌｏｙｄ聚集性指标＞１用幂指数法（Ｔａｙｌｏｒ）和ｌｗａｏ法分析结果表明，混播草坪上锈病株的田间分布型在平均发病率８．７—４１．２％范围内时其个体群为聚集分布．个体群内部分布是随机的，田间分布型属负二项分布．田间调查锈病株时，以对角线取样和Ｚ字型取样误差小．其抽样数量由平均发病率决定．发病程度越轻抽样量应越大．

A Preliminary Study on the Spatial Distribution andSampling Technique for Rust. Disease of Mixed-Seeding Turf

Rust disease (Paccinia cronata corda)is the major disease for turfgrass and oc cured commonly in our region. The growth and the coor and the quality of the turf were affected by this disease. The spatial distribution and sampling technique for damaged plants ofthe turf were studied preliminarily in order to prevent and estimate accurately in the stress.The damaged condition of 16 mixed-seeding plots were analyzed by systematic surveyin the field and using gathering indexes. Result showed: the coefficent of dispersion C>1,the index of negative binomial K> 0,R.M.(1962) and Kuno,E. (1968)CA> 0, index ofclumping of David and Moors (1954)1>0,index of patchiness OF lioyd 1,the lwaomethod and the Taylor method wete also used. Result indicated that the spatial distributionpattern of damaged plants (8. 7-41. 1% )of the turf was gathering distribution which belongsto negative binomial distribution.In gathering distribution was as a crowd in the field and in side distribution of a crowd was random.The reason for making up gathering was attributedto the characteristics of pathogenic bacteria themselves and the reactions upon the differentenvironmental condition.The samplimg of the diagonal and "Z"shape had the less error. Thesampling quantity was depended on the incidence of thd disease. The less the disease occured,the more the samples should be taken.