Powdery mildew of plants, apart from Leveillula taurica can caused by other genus of epiphytic parasites such as Oidium, Erysiphe and Sphaerotheca, depending on the host.L.taurica is an endoparasite which means that it penetrates the plant tissue through stomata and grows intercellularly. Eventually, the mycelium grows and appeared outside of the leaf via stomata, mainly in the lower side of the leaf(rarely grows on the upperleaf surface). On the contrary, the other powdery mildew pathogens are ectoparasites, which means that the fungi grows only on the upper leaf surface and doesn’t penetrate the plant tissue. Pathogen spores dispersed via wind and rain water. It is quite difficult to control the pathogen because it lives inside the leaf, most of its life. If not treated efficiently , it can destroy the entire crop. The pathogen can survive in volunteer plants in the field or in greenhouse. The symptoms of the disease can progressively decrease the productivity of the plant.
Leaves: Yellowish/light green irregular spots/lesions on the upper leaf surface that eventually turn brown, as a result of the necrosis of the infected plant tissue. In optimum conditions, a whitish, powdery fungal sporulation growth can evolve in the lower side of the leaf surface. The spots are gradually expands and the whole leaf dies. This may lead to defoliation.
Stem: Stunted appearance of the whole plant
Hosts: tomato, eggplant, onion, pepper, cotton
“Vegetable diseases” – Panagopoulos G.C.
Aegerter, B. J., Stoddard, C. S., Miyao, E. M., Le Strange, M., & Turini, T. A. (2014, June). Impact of powdery mildew (Leveillula taurica) on yield and fruit quality of processing tomatoes in California. In XIII International Symposium on Processing Tomato 1081 (pp. 153-158).