These weird tiny blisters appeared on an F1 hybrid used for grafting called Maxifort. Whatever it is, it had greatly weakened the seedlings prior to grafting. Other tomatoes grown in the same conditions and in close proximity show no sign of this, nor have I ever seen this. I’ve seeded them 3 different times since January and each time the seedlings were affected.
The bumps begin to appear on the edges and work inward. After a certain amount of the leaf is covered, the edges dry out. This continues until the leaf curls and eventually the branch falls off.
An internet search yielded nothing for ‘bumps/blisters on tomato leaves’ Most show bumps on the stems, which are common and not the issue here.
Did anyone else growing this variety (purchased from Johnnys) see this feature?
I’m wondering if it is a virus passed through the seed?
Please advise.
Thanks Mark. I thought maybe, but I used a magnifying glass and couldn’t tell with the magnification I had. They seem more like a blister.
Whatever it is, it does not appear to have affected the scions I grafted to it so far.
Thanks. It’s very odd. All three sowings of tomato varieties, spaced a month apart, and only Maxifort shows this - no sign on any of the others. Watering for all was the same.
Johnnys has an email in their inbox.
What about light level, was is the same as well? Also, I guess some varieties with stronger root pump water faster, but there is no good evaporation from leaves indoors, so those may be affected…
Thanks Galina, that’s the strange thing, everything happened to be the same for all 3 varieties. It could be a quirky thing with Maxifort (the fellow I spoke with on the phone said Maxifort was quirky). So I sent pictures and someone should get back to me. If Maxifort doesn’t like ‘wet’, it certainly isn’t the rootstock for here.
We’ll see how it does outside.
What I learned, it is not actually about them to be very wet - it is not enough light. They can stay directly under the light, but as soon as they tall enough for bottom leaves to be far from lights - it starts… Week outside, even if it is not clear sky - they improve very much. When I just started making my own seedlings I threw away at least 4 batches thinking it is a dangerous virus . Then I noticed, that ones that are on north-west window affected more than on south-east. And also the ones that grew in cooler temperature are better than the ones in the warmest spot… So I started to look for physiological disorder and found info about edema. Instead of throwing 5th batch out to the trash, I threw it out to the deck(weather permitted) and in a week they were just fine.
You’ve probably already thought of this, but I think it’s interesting that this only affect this one tomato cross that you’ve made. To me, this suggests one of a few things:
This variety caught a disease that is transmitted by seed. I’ve looked at a few, like tobacco mosaic virus, whose symptoms are not unlike what you describe. It seems like these diseases are rarely as severe as you describe, but descriptions do say that different plants react differently to these diseases, with some plants just being very susceptible. From my reading, there are ways to sterilize the seeds, although it doesn’t work 100% against all diseases. Still, something you may want to try.
You’ve bred a variety that, for some reason, has nutritional requirements that are different from most tomatoes. For example, magnesium deficiency sounds somewhat like what you’re describing. Maybe you could make sure you fertilize these plants ASAP with the most complete fertilizer you can find (or perhaps a mix of different fertilizers to cover all the bases.
Similar to #2, somehow you’ve bred a tomato that is hypersensitive to some environmental condition. Plenty of posters have suggested different things along those lines.
To me, this tomato almost sounds like more trouble than it is worth, but I understand the compulsion to figure out what’s wrong.
Also, have you done a post-morten on these tomatoes? Do the roots look ok, or do they look diseased, or have galls, or look rotten, etc? Have you cut through the stem? Are there brown streaks, like the vascular duct is clogged? Stuff like that?
@VSOP, I did not mean to give the impression that I did the hybridization. This is actually a popular Monsanto hybrid for grafting tomatoes onto. (I know , holding my nose). So I don’t get the credit for this.
Thanks for your analysis. I’m hoping it is not a disease transmitted by seed but that was my first thought after closely examining them.
None have actually died, well, actually, I cut the tops off to graft onto to them and the grafted plants look fine…at this point. I was wearing lighted magnifying glasses (like dentists use) and when doing the splice graft, and I noticed no irregularities - but really wasn’t looking for them.
It appears that your Maxifort plants are suffering from Edema (also known as Oedema). I have included a link to more information about this for your here: Oedema. This condition happens when the plants absorb more water than can be transpired from the surface of the leaves.
This condition is common at this time of the year when the weather tends to be cloudy and cool. It also tends to affect certain varieties more than others.
Even though the affected leaves may eventually die and fall off the plant, Edema is rarely fatal to plants.
I would suggest cutting back on the amount of water your plants receive, and watering them only when the top layer of soil begins to dry out. I would also recommend increasing the amount of light and airflow that your plants are receiving.
So I’m guessing that the tomato varieties that are bred to have uber vigorous root systems (for grafting purposes) are more likely to develop edema since their leaves cannot keep up with what their roots pull up from the soil. That explains why the other varieties with the same culture did not display these symptoms. This also explains why grafts would push apart - even though the rootstock was not watered prior to grafting. The vigor of this rootstock may need to be attenuated by holding off watering even moreso than with other tomatoes prior to grafting.
. Then I noticed, that ones that are on north-west window affected more than on south-east. And also the ones that grew in cooler temperature are better than the ones in the warmest spot… So I started to look for physiological disorder and found info about edema. Instead of throwing 5th batch out to the trash, I threw it out to the deck(weather permitted) and in a week they were just fine.
, holding my nose). So I don’t get the credit for this.
but that was my first thought after closely examining them.