powdery mildew of pea on pod

agricultural agriculture algeria ascochyta blight brown cercle circular conidia covered damage danger dead death disease erysiphe fabaceae farm farmer feed field food fungi fungus garden grain green health healthy horticulture jijel leaf legume lesion loss losses microorganism mildew mycelim natural nature necrosis pathogen pathology pea phytopathology pisi pisum plant pod polygoni powder powdery pycnidia ring safe safety sativum spot stem symptom target threat tissue unhealthy which white