Information and discussion for successfully cultivating potatoes, the world's fourth largest crop.
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September 29, 2012 | #1 |
Tomatovillian™
Join Date: Aug 2006
Location: TriCities, WA
Posts: 141
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Warty potatoes
What causes the warts on this red Potomac?
ImageUploadedByTapatalk1348974268.803644.jpg |
October 1, 2012 | #2 |
Tomatovillian™
Join Date: May 2011
Location: bald hill area thurston county washington
Posts: 312
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Looks like common scab..streptomyces acidiscabies.
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October 1, 2012 | #3 |
Crosstalk™ Forum Moderator
Join Date: Aug 2006
Location: 8407 18th Ave West 7-203 Everett, Washington 98204
Posts: 1,157
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The looks of it are too uniformly distributed to me to be scab. My guess is that it is due to wet soil and is likely swollen lenticels. Once they start...secondary infections often sets in and you have a host of maladies starting. Go to this site to compare...
http://www.greenlandgarden.com/veggie_woes.htm |
October 2, 2012 | #4 |
Tomatovillian™
Join Date: Feb 2006
Location: Alabama
Posts: 2,250
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Red Pontiac is also highly susceptible to nematode damage and there are a couple of nematodes that cause damage similar to the photo above. You can tell the difference by using a knife to slice the surface from one of the "warts". If there is an obvious blackened trail into the potato, then it is a nematode. Otherwise, it would probably be the lenticel problem as linked by Tom.
DarJones |
October 2, 2012 | #5 |
Tomatovillian™
Join Date: May 2011
Location: bald hill area thurston county washington
Posts: 312
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I stick by my diagnosis. The potato field guide to insects, diseases, and defects states "The bacterium enters newly forming tubers through immature lenticels." Swollen lenticels do not look so erumpent. But without laboratory analasis we are all just guessing. Common scab lesions often times will show mycelial growth when first dug from damp/wet soil.
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October 2, 2012 | #6 |
Tomatovillian™
Join Date: Feb 2006
Location: Alabama
Posts: 2,250
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wingnut, Red Pontiac is also highly susceptible to scab. that is why I no longer grow it. There are just too many diseases and pests that attack it.
DarJones |
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