Tuesday, 12 August 2008

Taphrina deformans: Peach Leaf Curl

[photos from The Fifth Kingdom Chapter 4b and Backyard Nature]

Genus: Taphrina
Family: Taphrinaceae
Order: Taphrinales

In Peach Leaf Curl the leaves become thickened, distorted and turn yellow or reddish in colour, later causing the leaves to turn brown, dusty with ascospores and to fall. Taphrina deformans also affects the flowers and peach fruits, causing them either to drop early or become crooked at the stem or develop reddish to purple, wart-like deformities on the fruit surface.

Peach Leaf Curl (Kearnseyville Tree Fruit Research and Education Centre, West Virginia University)

"the lifecycle begins with an ascospore. The ascospore itself produces smaller spores by budding. On the leaf surface these spores produce more spores by budding, and when conditions are just right the spores sprout mycelium -- maybe after two spores fuse together. The full story isn't yet known."
"The mycelium enters the leaf and works its way among the leaf's cells. At this time, while a lot of complex genetic stuff is going on inside the mycelium cells, something causes the leaf's cells to elongate, causing twisting and blistering of the leaf. Eventually certain cells of the mycelium begin enlarging, growing to such an extent that they cause the leaf's cuticle, or "skin," to burst. Now these special, enlarged mycelium cells work themselves onto the leaf's surface and form a very thin surface called the hymenium consisting of stacked-together, clublike asci. The asci rupture, releasing ascospores, and now the life cycle starts over."
[from Backyard Nature]

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