SUB DIVISION DEUTEROMYCOTINA
Deuteomycotina are also called fungi imperfecti because it includes those fungi in which only asexual ( inperfect ) stages are known and sexual ( perfect ) stages are not yet recorded . The classification of deuteromycotina is artificial hence the various taxa are known as form-order , form- family , form-genus etc .
FORM CLASS HYPHOMYCETES
Form genus Alternaria ( Form Order Monilliales )
Alternaria species are saprophytic or pathogenic . Alernaria solani causes early blight of potato . Symptoms appear as yellow brown spots ( in the form of concentric rings ) on the leaves . These are known as target board symptoms . Conidiophores may be geniculate ( bent like knee ) and conidia may be muriform ( brick like arrangement ) in shape . Perfect stage of alternaria is Pleospora infectoria .
Form genus Cercospora ( Form Order Monilliales )
They are mostly pathogens . Tikka disease of groudnut is caused by Cercospora personata . Perfect stages of species of Cercospora are included in Mycoshaerella .
Form genus Helmithosporium (Form Order Monilliales )
The conidium germinates characteristically from both the ends .
Form genus Fusarium (Form Order Monilliales )
Most of the species of Fusarium are facultative parasites . Characteristic symptom is wilting of seedlings and plants .
Form genus colletotrichum ( Form Order Melanoconiales )
Colletotrichum is a parasitic fungus causing anthracnose disease in plants . Colletotrichum falcatum is responsible for red rot of sugarcane . Acervuli ( having conidiophores ) and lesions appear on sugarcane stem . The internodes of infected sugarcane plants usually get shrink .