Re: RE:

Hi Stephen,
Well, I tell you, I don't know what this is. It really puzzles me. It just doesn't behave like bac. wilt. I have seen bac. wilt on my field pumpkins (C pepo.) and when they get it death is quick and complete with heavy wilting followed but dried up dead leaves. However, percentages of infected field pumpkins is very low, less than 1 percent. I grow up to 1000 field pumpkins every year so less than 1% loss is acceptable. Also, infected field pumpkins show the 'stringy sap test' confirming bac wilt, but AG's never show stringy sap.
AG's die very slowly and the wilting is never extreme, its just slight during the day and yellowish with severly stunted growth, but they hang on for a long time. To add a new wrinkle to this, a experimental AG crossed with Giant Zebra squash was infected and showed all the signs on the primary vine.The first secondary vine, unexplicably, did not show signs and matured a 150 pound pumpkin. I have never seen part of an infected plant set a pumpkins..why? my guess is to to its hybrization with the older more disease resitant variety. I did spray my most promising AG this year and it escaped disease and made it to 500 pounds. I have also found that the later the pumpkins are planted the less likely they are to be infected. 3 years ago I planted AG's in early May and then again mid June. All the May pumpkins were infected but none of the June pumpkins were. They both had the same seven sprayings. Sadly, the June pumpkins only had enough time to get to 250-300
After doing some reasearch, I have narrowed it down to a virus or bacteria. The bacteria may be other than the common bacterial wilt bacteria. I have found that there are many bacteria that can be transmitted to cucurbits from local vegetation through many different insects including, but not limited to cuc beetles, and squash bugs. Though, these are not common and can be highly localized. The only way I will really know is to send a tissue sample to a lab and have it offically diagnosed. Anyone have any idea how much this would cost?
Well, I think an better spray is the solution. I used triacide at recommended levels and it burned leaves when it was above 85 F. It did seem to kill large numbers of cuc beetles. but damages to leaves was pretty bad. Also, imidacloprid seems to give results below that of seven...it seems slow to kill the bugs. I may have to try the bifenthrin. Also, completely enclosing the plant would work but would have to regulated temp and water more often losing the benefit of rain water. 

Any advice would be greatly appeciated.

John

John Failor
Sandusky Valley Nursery
svnursery.com



Sounds like bacterial wilt which is vectored by cucumber beetles.



http://vegetablemdonline.ppath.cornell.edu/PhotoPages/Cucurbit/BactWilt/Bact
WiltPhotoList.htm



Have you seen any of these beetles?







Valley Green, Inc

Stephen J. Jepsen

823 Nichols Avenue

Stratford, CT 06614-3930

Tel: 914-260-7176

efax: 206-203-2397



-----Original Message-----
From: owner-pumpkins@hort.net [o*@hort.net] On Behalf Of 
John-Sandusky Valley Nursery
Sent: Monday, January 19, 2009 1:40 PM
To: pumpkins@hort.net
Subject: Re:
Hmm, this sounds very similar to a disease I have been fighting. This year 2 


plants had it. They did not die right away , took nearly a month. Plant

slowly turned yellowish and leaves wilted somewhat, and then slowly died
off. It did not grow at all after turning yellow. I sprayed with seven, and
it kept it off some of my plants but was not 100 percent effective. Also, it 


did not bother other pumpkins and gourds, only affected C. maxima.  Could

you send me more information on this disease?



Thanks,

John
----- Original Message ----- 
From: "Jessica S." <jschelske@wi.rr.com>

To: <pumpkins@hort.net>

Sent: Monday, January 19, 2009 9:16 AM






Research suggests that squash bugs carrying the pathogen (Serratia)



transmit it to the plant through feeding. Once infected, the plant
exhibits symptoms of yellowing and wilting foliage and stem discoloration. 



The plants collapse prior to fruit maturity, and death can follow. If the



plant lives, it will not produce any fruit.







The university of Ohio is researching this more...







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