Systematic position in plant classification: Helminthosporium is a fungus of the phylum-Deuteromycota, under the class- Deuteromycetes They are known as incomplete fungus.
Habitat: They live as parasites, in the leaf cells of different crops, such as paddy, wheat, burly etc.
i) Their mycelia extend and expand their branches through the stomata or broken cells from the lower surface of the leaf
ii) These branches are called conidiophores. The conidiophores contain conidia towards the apical parts.
iii) At the matured stage, conidia spread into other plants breaking up the sporangia and germinate in favorable condition to form new plants.
Reproduction: They reproduce by asexual method. As sexual reproduction is absent in them, they are called incomplete fungus.
i) Few species of them cause diseases in paddy, such as —leaf spots, stem rot etc. which reduce the overall production.
ii) Few species of them also cause food rot diseases in wheat and leaf spot and blight diseases in burly plants