COMMENTS ON ALTERNARIA
Habit
Alternaria is a facultative parasite occuring in a large number of host plants. Most commonly it is recognized in potato plants causing early blight of potato disease Alternaria solani.
Somatic structure
Mycelia:
The somatic body is represented by multinucleated mycelium. The Mycelium consists of profusely branched septate light brown hyphae which are intercellular at first but become intracellular with the ramification of hyphae without haustoria.
Asexual reproductive structures.
i) Conidiophores:
They are short and dark ordinary hyphae which emerge out through the stomatal pores or dead and damaged epidermis of host leaves.
ii) Conidia:
They are large or small dark coloured, mostly obclavate terminating into a long septate beak like structure. The body of conidia is divided into small comportments by both transverse and longitudinal septa.