紫花苜蓿病毒病病株空间分布型及抽样技术研究

The spatial distribution pattern and samplingmethodology of alfalfa virus-diseased plant in fields

摘要:

【目的】 明确紫花苜蓿病毒病病株空间分布型及其适合的抽样方法。【方法】 通过扩散型指标Iδ及其偏离度显著性F0检验、聚集指标（C，M*，M*/xˉ，I，K 与C）和Iwao 回归分析法研究了紫花苜蓿病毒病病株空间分布型。【结果】 紫花苜蓿病毒病病株空间分布型为聚集分布，分布的基本成分为个体群，个体群之间分布是聚集的；分析并确定了在不同病株率下保证抽样质量的理论抽样数量；通过对采用平行线、“Z”字型、“W”型、五点式、单对角线、双对角线6 种抽样方法获得的调查数据统计分析、比较，发现平行线抽样方法变异系数最小，更适合苜蓿病毒病病株空间分布型的调查。【结论】 紫花苜蓿病毒病病株空间分布型为聚集分布，适合的抽样方法为平行线法。

Abstract:

【Objective】 The objective was to ascertain the spatial distribution pattern of alfalfa virus disease strainand identify an appropriate sampling method.【Method】 The spatial distribution pattern of alfalfa virus ‐ diseasedplantswere studied using thediffusion index，its deviation significance（F0），aggregation indices，and the Iwao method.【Result】 The results indicated that the spatial distribution pattern of alfalfa virus‐diseased plantswere aggregate distribution，with thebasic compontent of distribution beingindividual groups. Their distribution was aggregated，showing anoticeable center of disease. The theoretical sampling quantity was determined under different diseased plant rates.Through statistical analysis and comparison of survey data obtained usingsix sampling methods （parallel line，Z ‐shaped，W ‐ shaped，five ‐ point，single ‐ diagonal and double ‐ diagonal），it was found that the parallel ‐ line samplingmethod had the smallest coefficient of variation and was more suitable for investigation the spatial distribution of alfalfavirus ‐ disease plants.【Conclusion】 Alfalfa virus ‐ diseasedplants exhibited an aggregated spatial distribution，andthe parallel‐line method was identified as the appropriate sampling technique for assessing spatial distribution patterns.