Agree with Dave.

Iron deficiency also looks like that--get your soil tested, especially pH, but if you've grown tomatoes there before with no problems, it's almost certainly glyphosate injury. Iron deficiency is comparatively much rarer than glyphosate injury.

If it's not too late in your season, I would recommend buying replacement plants. But make sure you figure out the source of the contamination first. If it's a neighbor, for instance, and s/he sprays again, you'll just end up with the same problem on your replacement plants.

Nitrogen deficiency in tomatoes is similar but not the same.

The bright yellow coloring of the newest cells is due to drift -- likely a sub-lethal dose -- from glyphosate.

Jean: iron deficiency does not look like that.

Agree that it's almost certainly glyphosate, as I said above. But iron deficiency does, indeed, look exactly like that sometimes.

Yeah Iron and Nitrogen deficiency aren't the same thing Jean.

Dave

Thanks for the replies, I found out my husband sprayed round up weed killer near the garden beds. Luckily only this tomato plant was affected out of the 22 tomato plants I have. Hopefully fruit production won't be too affected...

Yes , seems that some varieties are more sensitive.

CASE IN POINT: I have a sprayer that had been used as weed killer sprayer years before. I rinsed it few times and washed it few times with warm water and soap. Then I used it to spray fungicide. One of my plants slightly affected . The rest of about 25 are not affected.

sey

PS: I am going to wash and rinse it more.

The standard recommendation is to replace the plant as the odds of recovery are slim. Hopefully your husband now understands he can't do that. Spray can drift for up to 1/4 mile or more and tomato plants are especially sensitive to it.

Dave

Agree with Dave. Plants can recover and go on to produce, but they're generally set back a lot and usually have poor production.

Yeah I told him to never spray it again. It's a little late in my growing season. I live in zone 10b in Southern California, if I plant out a new tomato plant, I won't get much production from that plant because of the summer heat that comes in July. Should I just keep the damaged plant or plant a new one?

A store-bought early variety should have time to set fruit before July heat hits. Remember that heat affects fruit set. Once fruit is set, heat won't kill the developing fruits or anything. Meanwhile, this plant will need time to grow past the damage if it survives. Then it will need to bloom and set fruit. IMO it's the same difference in terms of timing, but the blooming and fruit set will prob. be better with a replacement plant. You can also replace it with a cherry, as cherries are not only early as a rule but also set in heat better than larger-fruited types.

How long after Roundup spray would this show up?

You can see signs the plant is unhappy in about two days after exposure, with the bleaching of the bases of the leaves very evident by 5 days or so afterward.

I sprayed the Roundup easily 2-3 weeks ago mostly approx 10 yards away and sparingly around the base of this raised bed, which is 4' tall. These leaves on mine are only a very small area, perhaps less than 10 leaves on a full 3' plant. Yellow is around edges on some leaves, blotches on others. Smaller tomato plants right next to this one have no indication. Thanks for your very timely response.

We'd need to see pictures. It could be related to the Roundup from weeks ago if soil and mulch have been moved, though not that likely, as glyphosate has a short half-life and doesn't wander or volatilize as much as other herbicides. Or perhaps just very slight exposure which took a while to show up? Sounds like it might be something else, though. Impossible to tell without seeing it.

A couple of years ago my neighbor got tired of weeding his garden so he sprayed round-up on the weeds growing around the base of each tomato plant (25 of them) ,,,,Big Mistake.