Difference between revisions of "AY Honors/Fungi/Rust infection"

Latest revision as of 23:25, 14 July 2022

Rust infection

Rust occurs on many species of plant, but in most cases any one species of rust can only infect one species of plant. The following describes the infection process of asexual spores.

Spore Attachment

When a rust spore lands on a plant surface it needs to attach to it, or it would simply be washed off. First, weak, hydrophobic interactions are formed between the spore and the plant cell surface. Then unknown signals cause the production of a substance called adhesin. This will stick the spore irreversibly to the plant surface. Once attached, the spore will germinate.

Germ Tube Elongation

Rust fungi penetrate the plant by using the natural pores on the underside of a leaf, but first the growing germ tube must locate it. The germ tube grows in a random manner until it reaches a ridge. At this point it will start to grow perpendicular to the ridge, greatly increasing its chances of locating a pore (called a stomata).

Appresorium Formation

The stomata is the site of a structure called an appresorium that functions to both firmly anchor the fungus and aid in penetration. From the appresorium an infection peg grows down into the plant and between the leaf cells.

The Haustoria

Rust fungi gain their nutrients from living cells. This requires a specialized penetration of the fungi into a living plant cell called a haustoria. This develops from a haustorial mother cell. The plant cell membrane surrounds the main haustorial body. An iron- and phosphorus-rich neck band bridges the plant and fungal membranes and acts as a seal preventing the escape of nutrients into the plant. The rust fungi will then continue to grow and invade the plant until it is ready to make new spores.

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-''This article is about the fungus. For the corrosion process, see [[rust]].''
+<noinclude><translate><!--T:1-->
-{{Taxobox begin | color = lightblue | name = Rusts}}
+</noinclude>
-<!-- {{Taxobox image | image = | caption = }} -->
+[[Image:Rustinfection.JPG|thumb|450px|Rust infection]]
-{{Taxobox begin placement | color = lightblue}}
+Rust occurs on many species of plant, but in most cases any one species of rust can only infect one species of plant. The following describes the infection process of asexual spores.
-{{Taxobox regnum entry | taxon = [[Fungus|Fungi]]}}
-{{Taxobox divisio entry | taxon = [[Basidiomycota]]}}
-{{Taxobox classis entry | taxon = [[Urediniomycota]]}}
-{{Taxobox ordo entry | taxon = '''Uredinales'''}}
-{{Taxobox end placement}}
-{{Taxobox section subdivision | color = lightblue | plural_taxon = Families}}
-[[Pucciniaceae]]<br/>
-[[Melampsoraceae]]<br/>
-[[Coleosporiaceae]]<br/>
-[[Cronartiaceae]]<br/>
-[[Phragmidiaceae]]<br/>
-[[Pucciniastraceae]]
-{{Taxobox end}}
-'''Rusts''' are [[fungi]] of the order [[Uredinales]]. Many of these species are plant [[parasites]]. Some are superficially similar to the [[smut]]s, although their relation to each other is not clear. The taxonomy of Urediniomycota, as a whole, is in a state of flux.
-Many of the rusts have two or more hosts ([[heteroecious]]) and up to five spore stages. Among them are ''[[Gymnosporangium]]'', the [[juniper]]-[[Apple (fruit)|apple]] and [[juniper]]-[[hawthorn]] rusts.
+<!--T:2-->
+;Spore Attachment:
+When a rust spore lands on a plant surface it needs to attach to it, or it would simply be washed off. First, weak, hydrophobic interactions are formed between the spore and the plant cell surface. Then unknown signals cause the production of a substance called ''adhesin''. This will stick the spore irreversibly to the plant surface. Once attached, the spore will germinate.
-The group received its common name from the fact that some species have a reddish [[spore]] stage, which resembles the corrosion process known as [[rust]].
+<!--T:3-->
+;Germ Tube Elongation:
+Rust fungi penetrate the plant by using the natural pores on the underside of a leaf, but first the growing germ tube must locate it. The germ tube grows in a random manner until it reaches a ridge. At this point it will start to grow perpendicular to the ridge, greatly increasing its chances of locating a pore (called a ''stomata'').
-==External links==
+<!--T:4-->
-* [http://botit.botany.wisc.edu/images/332/Basidiomycota/Teliomycetes/Uredinales/ Images of some rusts]
+;Appresorium Formation:
+The stomata is the site of a structure called an ''appresorium'' that functions to both firmly anchor the fungus and aid in penetration. From the appresorium an infection peg grows down into the plant and between the leaf cells.
-[[nl:roesten]]
+<!--T:5-->
-[[Category:Fungi]]
+;The Haustoria:
+Rust fungi gain their nutrients from living cells. This requires a specialized penetration of the fungi into a living plant cell called a ''haustoria''. This develops from a haustorial mother cell. The plant cell membrane surrounds the main haustorial body. An iron- and phosphorus-rich neck band bridges the plant and fungal membranes and acts as a seal preventing the escape of nutrients into the plant. The rust fungi will then continue to grow and invade the plant until it is ready to make new spores.
+{{clear}}
+<noinclude></translate></noinclude>