With Tomatoes Failing, Why Are Mine Alive?

I've seen many articles about the tomato blight hitting the northeast, though what I find curious are the plants that avoid it, like the sungold tomato above. It's a hybrid variety though not immune to late blight.

In my community garden, many plants have succumbed to the disease but several in my plot are growing, the tomatoes maturing, including heirloom varieties. My yield though is down from last year.

In my sheltered backyard, where I grow sungold and heirloom chocolate cherry tomatoes in large pots, with nary another tomato plant in sight, I've no blight at all. Is it the variety? Is it the sheltered location? My friend, Jim Crawford, a Pennsylvania organic farmer, says: "No question, location makes a huge difference."

George Ball, who heads up Burpee Seeds, argues on his blog that heirlooms are least resistant to the disease:

If the spring and summer of 2009 is followed in succession by similar seasons in 2010, 2011, 2012 and 2013, we could face a complete extinction of many—not all—of the old-fashioned heirlooms and open-pollinated tomato varieties that folks in the Northeast have come to enjoy since those varieties were reintroduced in the early 1980s.

Now Burbee sells a lot of disease-resistant hybrids, which gardeners must buy each year because they are not open pollinated. But I see no reason why open-pollinated versions will fail to develop resistance on their own. Why not get a healthy heirloom standing tall in a field of failed plants and then breed it?

That's exactly what Crawford is doing. "We've got one field of Brandywines, which went completely brown, but in the middle are four plants that are green from top to bottom," he said. He's saving the seed for next year -- something you can't do with hybrids.

This dovetails with something Jim Gerritsen of Wood Prairie Farm writes about in his seed company's newsletter:

I know organic seed growers and breeders often prefer open pollinated varieties because type selection is fully within their control. This allows a practical and decentralized way of developing regionally adapted varieties that excel and resist disease pressure and certainly that's what we need as was made very clear by this year's cold wet conditions in the Northeast.

Who knows. Maybe one's even growing in my backyard. 

- Samuel Fromartz

Comments

[emily brown rosen]

Hi Sam,
I don't think it's possible to kill a Sungold! They are the best ever cherry tomato, with an intense flavor that is hard to match- but also the most wild, jungle like tomato plant there is. Impossible to fully control, rampant vines, something appealing about that. I am down to planting only 1 Sugold out of 36 or so plants in my garden. But now it is acting as shade provider for the Ramapos (a NJ hybrid from the 70s that is a personal favorite and has been revived) which I pruned really hard when the blight hit, leading to some sunburn. But -- the Ramapos survived, after pruning religiously and 3 sprays of copper soap. The tops look great now. And the tomatoes are big and very high yielding (not my experience with heirlooms)
I'm hearing from Cooperative Extension that this strain of late blight was not as severe (as pathogenic) as the strains hitting potatoes in prior years. Thank goodness.

Clearly there is a difference in varietal resistance. My limited observation was that Valencia, a potato leaf variety (similar leaf type to Brandywine) was susceptible. Also the Moreton variety, which is another NJ variety Rutgers brought back did not fare as well. I think George Ball is overstating the potential future disaster on heirlooms, but they definitely have less disease resistance for early blight (the common every-year tomato disease), so this is not surprising either. There is a reason plant breeders come up with new varieties.

See my article at www.paoroganic.org on what to do when you have blight.
also, the Resource Guide for Organic Insect and Disease Management ...
http://www.nysaes.cornell.edu/pp/resourceguide/

happy salsa,
Emily