Mildew on tomato leaves

Powdery mildew on tomatoes is restricted to warm, arid and semiarid climatic regions. A fine talcum-like powder growth develops on the leaves resulting in the loss of 30-40% of the leaf canopy. Defoliation predisposes fruit to sunscald and reduced quality. The tomatoes become soft or are burned before they reach maturity.

“Powdery mildew is a serious economic problem in Mediterranean tomato production. The disease is currently controlled by fungicides (especially sulfur) in both conventional and organic production. In addition to causing reductions in yield and quality, it may make plants vulnerable to secondary infections by other fungal pathogens (e.g., Botrytis cinerea). Fungicides are used to control tomato powdery mildew, even in organic production, where sulfur fungicides are permitted and widely used.”

Authors: N. G. Dafermos, et al.
Affiliation: School of Agricultural Technology, Technological Educational Institure of Crete, Heraklion-Crete, Greece.
Title: Integration of Elicitors and Less-Susceptible Hybrids for the Control of Powdery Mildew in Organic Tomato Crops.
Publication: Plant Disease. 2012. 96(10):1506-1512.