Spatial Pattern of Southern Stem Rot Caused bySclerotium rolfsiiin Six North Carolina Peanut Fields

Frequency distributions of southern stem rot lesions in 5 of 6 data sets from groundnut fields sampled in 1980-82 were fitted by a negative binomial distribution, indicating that disease occurred in a clustered pattern. Incidence was 5.4-32.3% in the 6 fields sampled. Estimates of the parameter k of the negative binomial distribution were 0.87-6.49 and generally increased with plot size and with the population mean. Incidence of lesions in 3 fields was positively correlated with soil bulk density. Spatial correlations calculated from data from 3 fields indicated different patterns of disease in each field