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That State Up North

I have been mostly on the bench with regards to pumpkin growing the last several years, but have begun to gear back up again. I grew just a few plants last year to competitive care standards, mainly focusing on some genetics heavily concentrated on 1161 Rodonis and the highest % heavy offspring, the result was a complete loss due to pythium. This began me considering that there may have been an inadvertent selection among the best modern giant genetics for disease susceptibility. My hypothesis begins with the notion that most growers at the highest level have very intensive fungicide programs (I was going light IPM/organic because there had never been pumpkins where I was growing). Due to the lack of a need for any genetic resistance to the most prevalent pumpkin diseases in the pumpkin patches from which primary genes have been selected over the past 5 years there has likely been no selection for any traits related to disease resistance. The hypothesized result would be inadvertent loss of genes related to disease resistance. There is very little data widely available on the plants that have died off due to disease, or causes of loss of plants which never make it into the GPC database. So I am searching for speculation from other growers who may have noticed particular modern sets of genetics which have greater or lesser tolerance to specific diseases. Back in the good old days when I grew 500+ giant pumpkins I would see very clear differences between blocks of 20 plants of the same seed in the level of disease resistance. For this reason I know there is a natural amount of variation within the giant pumpkin gene pool. I am wondering if there have been some valuable traits lost in the past 5-10 years of competitive selection. Or maybe they aren't valuable traits so long as everyone has a good spray program.

Any observations from people more "in the game" the past 5 years?

1/10/2013 10:08:16 PM

South East

Finally somebody thats paying attention. Disease resistance should really be one of our main goals next to size.
i would say that about 80% of what we do revolves about pest and disease control. And no matter how severe the programm theres always that one spore that seems to make it thrue.
Selecting for resistance only makes sence. And we have been foolish to neglect that part of growing.
I dont really to select for it though because i,m forced to go by other growers obeservations. Always subjective, always with good intentions but hardly ever correct or trustworthy. Theres no good info out there really...
Without solid scientific individuals representing enteties that actually investigate these issues, its just another growers guess.

Somthing that could reveil patterns in disease, areas of the country and world in wich its worst would be a:

Giant pumpkin disease data bank

It would have specific incidents of disease for every grower just like aggc has info on its fruit.
This would link disease to weather patterns, regions, soil conditions. It would also shed more light on effective fungicides. All of this specific to our fruit of choise.

Breeding in resistance could be a long and painstaking procces of trial and error, with no garantee of succes.
Hens the fungicide,,wich may or may not had negative effects.

My gut says your on to something.

1/11/2013 6:13:34 PM

Hinckley MN

But there is no prize for the most disease resistant plant. Anytime you increase the number of traits you select for, you decrease the rate of improvement on those traits.

1/11/2013 9:09:05 PM

South Bloomfield, Ohio

A very interesting thread indeed Nic. I've noticed over several years of growing that some plants are prone to certain diseases and infections while plants on either side of them are disease-free.

The simplest way to control diseases to date is to prevent them in the first place with a rotation of pesticides and patch locations and planting natural soil fumigants such as mustard in fallow patches within our rotation area.

However, it is logical to believe that we may be inadvertently breeding pesticide-tolerant diseases much like we've done with weeds with the prolific use of Roundup. We all love to take the easy way out but it may cost us dearly in the end.

Also, I sometimes wonder if diseases aren't transferred through seeds from infected patches. No doubt it will take a lot of time to breed disease resistance into AG's.

1/11/2013 9:24:19 PM

Cincinnati,OH

I tried an experimental cross in 09.
http://www.bigpumpkins.com/Diary/DiaryViewOne.asp?eid=124338

1/12/2013 5:26:24 PM

Cincinnati,OH

I grew it in 10 but didn't get any viable seeds.
http://www.bigpumpkins.com/Diary/DiaryViewOne.asp?eid=145893

1/12/2013 5:29:08 PM

Lakewood, CO

Interesting post - You know in the years I've been in the horticulture industry, I've rarely met anyone who was truly knowledgeable in plant pathology. I always found that rather scary when you consider events that have taken place over time related to plant pathology - Irish potato famine for one.

I've spoken to other growers about this and have heard stories of growers sending in the same leaf sample from the same plant to two different labs for tissue testing - only to receive two completely different results back from the labs. I've always felt a bit vulnerable in regards to that issue, and really question how knowledgeable we are in regards to plant pathology?

You can't say there's no information about plant failure being reported, but it's only human nature to report your successes. Vegas comes to mind. I agree with you - valuable information is being lost because it's not being compiled.

1/14/2013 2:21:35 PM

Colorado

Yep,the hobby has been breeding for weight or beauty only.Long term ags may become candy asses. However plants that produce 1500# plus fruit may have have inherent disease resistance.When you consider how much reserves(a big fruit takes out of the plant) and for how long the plant has to stay healthy to produce a monster-we might be selecting somewhat for disease resistance without knowing it. Time will tell

1/15/2013 2:00:47 AM

Central Minnesota

Very good point cojoe...goes back to survival of the fittest.

1/15/2013 9:01:39 AM

President - GPC

Selective breeding at itZ best....

1/15/2013 10:05:28 AM

Connecticut

Nic-

From my experience cucurbits in general are susceptible to many diseases, and when you say that you have seen differences in disease resistance levels over a large sample size what diseases are you talking about?

For us growers trying to grow the biggest pumpkin possible we are putting an increased level of stress on the plant to produce such a large and continually growing storage organ so it would seem that the rate of disease incidence would also increase. What makes it difficult to compare disease susceptibility across the world is that there are different disease pressures in different regions on any given year.

Now my “in the game” experience with some plants in the greenhouse has shown differences in Powdery Mildew tolerance. The clone material from the plants that grew the 1663 Zoellner and the 1723 Marshall did seem to get powdery mildew at a delayed rate compared to the other plant material I had at the time.

In the field pumpkin industry there are some more tolerance options available (powdery mildew and some viruses), but the Atlantic Giants are actually in general more disease resistant in general than most Cucurbita pepo’s.

Hope this helps.

1/15/2013 4:59:13 PM

Leerdam, The Netherlands

Matt, Nic,

1663 Zoellner came to my mind also. could be your starting point

1/16/2013 3:15:10 AM

Georgetown, Ontario

It's funny, the 1663 Zoellner has been mentioned a couple times and I grew the 1663 and an 1161 Rodonis two years ago. The difference between the two plants was amazing. While the 1161 was eventually 50% rotted away due to pythium the 1663 never lost even a single leaf. The 1161 was eventually 25% covered in Powdery Mildew while the 1663 never got any. I remember seeing a picture in Jeff Zoellners diary showing how healthy the 1663 was in October so there is definately some good disease fighting genes in that one.

1/18/2013 5:40:53 AM