qLeptomytales Leptomytales
It is a order of oomycetes
systematic position
kingdom . Fungi
Division Eumycota
Sub Division Mastigomycotina
Class Oomycetes
Order Leptomytales
Occurance
it is the small order with about 8 genra and 21 species which are either saprobes of fresh water or of polluted water .
Mycellium
Aseptate hyphae at intervals frequently plugged with cellulin and presence of one oospore in the oogonium.Chitin is present in the cell wall that is seems to be absent in all other oomycetes.Thallus bear basal holdfast bearing erect hyphae.
Reproduction
Asexuall reproduction is takesplace by means of biflagelate zoospores .Zoosporangia are usually terminal clyndrical ovoid , or pyriform and the zoospores are formed within the zoosprangia.the species may be diplantic with two swarming period and monoplantic with one swarming period .
Majority of spesies of leptomytales are homothallic except one specie sapromyces.
Sexual Reproduction is Oogamous and takes place by gamitangial contact.Anthridia are usually present.Oogonia are usually uniovulate .Oospores are large with thick walls and a central reserve globule as in the prenosporales .
The way the oospore germinate is not well known
This order devided into two families
i)Leptomitaceae
ii)Rhipidaceae
Refrance
.http.Newage.com(introduction to mycology)www.newage.com