Forecasting and control of leaf and pod spot (Mycosphaerella pinodes) on field peas

A series of trials on winter and spring sown field peas was carried out at sites in the east and south west of England during 1998 and 1999. Differing numbers of sprays of chlorothalonil plus carbendazim were applied in order to either prevent or allow the development of Mycosphaerella pinodes at different times. Disease control and yield response started to decline when the first spray was applied after mid-flower. Meteorological data and the dissemination of spores of M. pinodes were monitored at an additional site by exposing trap plants. In each year, the most intense periods of spore dispersal occurred after rainfall. Variations in levels of M. pinodes developing on a range of field pea cultivars suggested that moderate levels of partial resistance were present in some material.