Efficacy of some fungicides against late blight of tomato

V. Alexandrov

Abstract: The influence of some fungicides, recommended for use in Bulgaria for control of late blight of tomato, was observed in an experiment carried out at PPI-Kostinbrod. The effect of the active substances dimethomorph, cymoxanil, azoxystrobin, famoxadone, chlorothalonil, fenamidone, fosetyl-AL, cupric oxychloride and cupric hydroxide and some major products based on them (Acrobat R, Equation Pro, Quadris, Banco, Verita and Funguran) was studied. A variant with no application of fungicide was used as a control. All tested chemicals except azoxystrobin (Quadris) suppressed the appearance of late blight of tomato. Preventive spraying of plants with fungicides by mid-August was а precondition for significant development of the disease at the end of the vegetation period. The treatment of plants with contact fungicides by the end of August provides good protection of their leaves and fruit until crop harvest. During the period of the study, a strong manifestation of brown leaf spots was observed along with the symptoms of the late blight. This disease was considered to be the second most important one for the crop.

Keywords: early blight; fungicides; Phytophthora infestans; potato late blight; tomato

Date published: 2019-10-16