Pests, Diseases and Other Problems
|
Subject: Big dark brown dead spots on leaves
|
|
From
|
Location
|
Message
|
Date Posted
|
EndlessTrail |
Fresno, CA
|
I could use some input on this mystery damage. I don't know if it is just the effect of senescence on leaves that had suffered earlier burn damage of somde kind, or if it is a disease. The brown dead spots on leaves started on a couple leaves four days ago on pollinator plant and now are on 12+ leaves on main plant. I'm on day 31 with fruit trying to make it as long as possible.
http://bigpumpkins.com/Diary/DiaryViewOne.asp?eid=142301 http://bigpumpkins.com/Diary/DiaryViewOne.asp?eid=142302
|
8/9/2010 2:30:48 PM
|
pumpkin cholo |
Bloomington, IN
|
I have the same thing trying to get started on my plant. Started out on a couple of leaves, then two days later its on a dozen or so. Mancozeb seems to have halted it's spread temporarily...I'd like to know what it is too.
|
8/9/2010 2:50:13 PM
|
Tremor |
Ctpumpkin@optonline.net
|
This could be fungal but also appears mechanical...how often have these been fertilized? How heavy?
|
8/9/2010 9:59:39 PM
|
swaintech |
churchville, ny
|
Could it be anthracose? OR the 2nd photo looks like the leaf has bird shit on it - could it be that acid burning the leaves?
|
8/9/2010 11:16:17 PM
|
EndlessTrail |
Fresno, CA
|
Tremor - I Fertilized once every 7-12 days with low strength (usually 1/4 to half recommended strength/dilution) neptunes harvest fish and kelp (2-4-1). Also about once a week with compost tea. They have also been sprayed at times with dawn soap (4x this season), milk (4x this season?), safer soap (twice this season) and organicide (2x this season), low concentration 0.8% Copper Soap fungicide (1x this season). I always spray in the early morning or late evening.
|
8/9/2010 11:56:46 PM
|
EndlessTrail |
Fresno, CA
|
swaintech - I think you're right - the pics of anthracnose definitely look like what I have. The only part that doesn't fit is that it's supposed to be a problem when warm rainy weather hits. We havent had rain for months here. I do have frequent misting on one plant which would match. But the pollinator plant only gets one manual misting a day and it developed the symptoms first.
|
8/10/2010 12:21:54 AM
|
pumpkin cholo |
Bloomington, IN
|
I put some pics in my diary showing it. The first three photos are from this years plant, the next two are what it progressed into when my plant got it last year.
http://www.bigpumpkins.com/Diary/DiaryViewOne.asp?eid=142314
The only fertilizer my plant has gotten is a weekly foliar of fish and seaweed with a bit of molasses mixed in.
|
8/10/2010 2:13:47 PM
|
EndlessTrail |
Fresno, CA
|
I agree pumpkin cholo - it looks like the exact same thing.
|
8/10/2010 4:15:12 PM
|
pumpkin bell |
Alabama
|
I have it too I was wondering if it was Downy Mildew check it out. http://www.bigpumpkins.com/MsgBoard/ViewThread.asp?b=6&p=357508
|
8/10/2010 5:07:44 PM
|
rybec |
Montgomery, IL
|
YA ,i have the same issue i have lost all the leaves three feet from the stump on one plant????
|
8/10/2010 5:42:40 PM
|
EndlessTrail |
Fresno, CA
|
pumpkin bell, I'm not sure. It does look like what you have too. Most of the downy mildew pictures I have seen on the internet have more yellow spots per leaf to start with and the yellow color terminates at the edge of leaf veins very abruptly giving it an angular look. That is why I am thinking this is anthracnose like swaintech suggested. However I think the optimal temperature range for downy mildew is warmer than for anthracnose which would seem to be a better fit for our hotter climates. I treated with Serenade Garden(on both soil and leaves) yesterday morning. I think it did some shock to the soil microbe community in my patch because growth on both plants dropped considerably today. One plant dropped from 8lbs to 5lbs and the other from 5lbs to 1lb. So be warned - a traditional chemical fungicide may be a better idea than what I did.
|
8/11/2010 11:54:49 AM
|
EndlessTrail |
Fresno, CA
|
rybec, can you post some pics on your diary of the problem leaves?
|
8/11/2010 11:57:05 AM
|
Tremor |
Ctpumpkin@optonline.net
|
I must have never hit post reply....regardless, if you are sure nothing has been dripped or misapplied, I'd either find an experienced grower/mentor/club or find the local free entomologist in the blue pages. California has great resources.
|
8/11/2010 1:41:29 PM
|
Peace, Wayne |
Owensboro, Ky.
|
Leaf tissue analysis...is this a possibility? Peace, Wayne
|
8/12/2010 12:35:41 AM
|
Tremor |
Ctpumpkin@optonline.net
|
Is this damage limited to those leaves that were covered in a cloche this spring?
|
8/12/2010 1:22:52 AM
|
rybec |
Montgomery, IL
|
EndlessTrail ,yep ill try to take some today and post later
|
8/12/2010 8:37:37 AM
|
EndlessTrail |
Fresno, CA
|
Thanks Tremor, I will see what resources our local university ag extension office has. I didn't use cloches at all. Only cover of any kind I have used is the 22% white shade cloth about 5.5 feet above ground. Wayne, I hadn't thought of tissue analysis. Is that expensive?
|
8/12/2010 3:35:18 PM
|
EndlessTrail |
Fresno, CA
|
Pumpkin cholo sent me some great info he got from North Shore Boyz on Anthracnose, and how to prevent it with Companion, and Infuse systemic and milk. Also pumpkin cholo said mancozeb stops it from spreading.
|
8/15/2010 1:34:23 AM
|
Total Posts: 18 |
Current Server Time: 9/2/2024 11:25:53 AM |