Efficacy of fungicides in the control of Pseudocercospora fuligena on tomato

We examined the fungicidal effects of 16 fungicides on Pseudocercospora fuligena by examining spore growth in a spore suspension on tomato. One-tenth of the registered concentration of TPN, cymoxanil plus TPN, and azoxystrobin plus TPN completely controlled spore growth and showed high fungicidal activity. We also examined the fungicidal effect of TPN, polyoxin, iminoctadine albesilate, and azoxystrobin on Pseudocercospora fuligena on tomato by spraying a field at 14-day intervals. On the basis of our findings and the assumption that the environment would be less suitable for disease and the likelihood of infection would be reduced, we recommend that TPN, alone or in combination, or iminoctadine albesilate be sprayed preventively at 14-day intervals from the initial incidence of Pseudocercospora fuligena.