A recent article in the news paper concerning a disease called late blight caused by an oomycete pathogen has seed potato growers in Montana concerned. The disease travels on the wind and there is no cure once the crop is affected. Tomatoes, peppers and egg plants are also affected by the disease which rots the fruits. Cool, wet weather contributes to the spread of the disease and that is just what we are seeing now. Montana seed potatoes are a multi-million dollar business providing seed potatoes to a large part of the northwestern states which are responsible for much of the nation’s potato production. The first sign of the disease came late last season and still had a huge effect on seed potato production. The disease is incredibly aggressive and spreads like dandelions according to the article, and can over winter in the soil. The method of prevention recommended is an early crop fungicide application but no more information was given on the subject. Apparently there are some organic preventative measures as well.
And I thought the Colorado potato beetle was my worst nightmare. I intend to do some more research on the subject and would appreciate the help of anyone else interested.
Irish Potato Blight - 1840's - Back again in MT
The method used by Victorian gardeners and farmers was to grow as many different varieties as possible so if one got hit the others might get missed. Our problem now is we are growing so many vegetables as monocultures which was the problem in the Irish Potato Famine. The Irish were growing basically one type of potato, so when the pathogen came in from South America it could go through like a dose of salts. The interesting thing is it hit England and caused a famine there first before it hit Ireland. Its just that England had more resources. From what I understand they've pretty much given up trying to find a cure and are just concentrating of developing a resistant or partially resistant variety. Another interesting point is the Andean Indians still grow potatoes in the old way. They grow different variaties in several different locations in several different fields so if one or two get hit one or two still have a good chance of survival. What a concept!
There are signs up in the nurseries here in Bozeman begging home gardners to spray their potatoes and tomatoes with fungicides so they don't inadvertently contribute to wiping out the commercial growers.
mraider, do you use any particular spray? I have one called Fungonil (I think), but they suggest rotating between a couple different ones to get a full spectrum coverage.
Interesting comments yehudith. The same philosophy should and does apply to most gardening practices. I down loaded an article from Cornell University yesterday which states the "Planting resistant varieties will slow down (but not prevent) the development of the late blight. Currently, 'Defender' and 'Elba' are the most resistant varieties available." They also mentioned Kennebec, Sebago, and Allegany as being moderately resistant. Since the problem is equally as devastating to tomato plants I am wondering how it may affect my Stupice tomatoes which are my primary variety this season. The article mentions "Mountain Magic" as one of the first cherry tomatoes which was developed to be resistant to the disease and that other resistant strains would soon be developed. I think Carolyn might have something to say on the subject.
seran, I haven't checked yet on any fungicide sprays which might be available locally. As much as I hate the thought of using them I do not want to risk infecting either my neighbor’s garden or possibly have an effect on some commercial grower. Our prevailing winds are generally out of the west or North West which actually blow in the direction of the commercial growers in your area. We barely managed to harvest our potatoes last season before the cold, wet weather hit. A number of the gardeners in our area were not so lucky losing both corn and potatoes to the sudden change in weather. That is when I heard that a number of the commercial growers lost a good portion of their seed crops, but it was not until I read the article in the paper that I realized there was this hug concern about late blight. I appreciate your advice on the rotation of the fungicide sprays. My new neighbor who also gardens is an employee of the Ag Department and I have yet to visit with him on the subject but I will keep you informed of any developments on this end.
Thanks for the feedback.