Spatial distribution pattern and sampling technique for the fungal wilt disease in watermelon fields
西瓜枯萎病病株空间分布格局及其抽样技术

The precent paper dealt with the spatial distribution pattern and sampling technique for the fungal wilt disease, Fusarium oxysporum Schl., in the watermelon field. The tests of frequency distributions indicated the all samples were not fited to the evenness distribution, but to the poissson, neyman, negative-binomial, poisson-binomial, or compound poisson distributions, respectively. The analyses of aggregation indexes displayed that Lloyd's index of mean crowding (m~*) ranged between 1.533 and 1.983. Cole...