Abstract
A epidemic of banana leaf spot [Mycosphaerella fijiensis var. difformis] was monitored every 2-4 wk for five continuous growing seasons from 1980 through 1985 in 10 locations of southern Taiwan. There was a linear relationship between disease severity (calculated according to Stover''s international scale) and incidence (proportion of leaves diseased) when both variates were logarithmically transformed. The slope of the relationship was consistent over the five growing seasons but varied according to location. This variation may reflect an important distinction between disease epidemics in temperature and tropical regions. There was no consistent relationship between the estimated parameter values for the incidence-severity relationship and the overall level of disease (incidence or severity) at each location.