Control of Verticilliosis and Grey Rot of Tomatoes Using Phosphite-Based Fungicides

Abstract

In vitro, three phosphite formulations (zinc phosphite-manganese, iron phosphite, and copper gluconate) were tested for growth and sporulation of Verticillium dahliae and Botrytis cinerea. The three phosphite formulations tested showed notable antifungal activity against the two pathogenic fungi. In vivo, iron phosphite was tested in a greenhouse to protect tomato plants against the development of grey rot induced by B. cinerea. The effectiveness of the curative and preventive treatment of this fungicide was evaluated by measuring the severity of the disease and the sporulation of the fungus on the host. Iron phosphite was the most effective against sporulation of B. cinerea. In vivo, curative treatment with iron phosphite was more effective than preventive treatment in reducing the severity of grey rot and fungal sporulation. Iron phosphite has proven to be a promising alternative to traditional chemical pesticides to control verticillium wilt and gray rot in tomatoes.