Parsley

Typical symptoms of Septoria on parsley (caused by S. petroselini) are brown lesions sometimes with yellow haloes, on leaves and cotyledons. As the lesions age, the centres turn tan or light grey.

Tiny black fungal spore cases (pycnidia) are often visible within the lesions and this is a useful diagnostic feature. When infection is severe, leaves may die and drop off, and lesions may develop on petioles.

Coriander

Symptoms due to Septoria sp. are similar to those on parsley

Lemon balm

On lemon balm, septoria lesions (S. melissae) are dark brown/black, 1-2 mm in diameter and angular in shape (constricted between leaf veins). Spore cases are sometimes visible within lesions on the underside of the leaf.