The Peronosporales are an
order of
water mould
Oomycota forms a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms, called oomycetes (). They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction of an oospore is the r ...
s (class Oomycetes) which can be
pathogenic.
Many diseases of plants are sometimes classified under this order, but are sometimes considered members of order
Pythiales
Pythiales is an order of water-molds (oomycetes). Some species of this order are the causative agents of several economically important plant diseases, such as potato blight
''Phytophthora infestans'' is an oomycete or water mold, a fungus-li ...
. Some of these pathogenic protists include the organisms responsible for
potato blight
''Phytophthora infestans'' is an oomycete or water mold, a fungus-like microorganism that causes the serious potato and tomato disease known as late blight or potato blight. Early blight, caused by ''Alternaria solani'', is also often called "po ...
,
eucalyptus dieback,
sudden oak death
James Green aka "Sudden" is a fictional character created by an English author Oliver Strange in the early 1930s as the hero of a series, originally published by George Newnes Books Ltd, set in the American Wild West era. Oliver Strange died i ...
, and
blue mold
''Peronospora hyoscyami'' f.sp. ''tabacina'' is a plant pathogen infecting tobacco that causes blue mold. It is an oomycete (a fungus-like organism) that is highly destructive toward seed plants. It is very prevalent in humid farming zones, ...
. Further genetic studies may place these organisms more definitively in one order or another.
References
Heterokont orders
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