What the heck? Late blight?! Please help

[Mark0820]

Originally Posted by carolyn137

If it were me I think I'd check all other plants first, then if nothing, blast those lesions with Daconil, your Ortho product, and watch it closely.

I checked all of the other plants and there are no lesions or leaf spots on them. I blasted the lesions three times with the Ortho product, and decided to spray all of the plants. There are three lesions in total, all in the 2nd foot of the plant. The plant is about 3 1/2 feet tall and looks extremely healthy from the foliage.

I had a problem with Sarah Black last year (black spots on the leaves that turned brown and crunchy). It seems like there might have been lesions on the stem also, but I can't be sure. I might just be thinking there were lesions since I saw them this year. Anyway, Sarah Black was very productive and produced right up until frost (I just kept pruning all of the lower leaves.).

I guess I will see what happens next. My only concern is the rain in the forecast for tomorrow and Saturday. Hopefully it will miss us.

[Mark0820]

Well maybe I do have late blight. I found this link:

http://www.longislandhort.cornell.ed...ato.htm#images

The third photo down labeled "leaf lesions due to late blight" looks very much like the leaves on my Sarah Black last year (only the spots were much smaller than what is shown in the photo). There were black spots on the leaves before they turned brown and crunchy.

However, last year I didn't spray for disease at all, and Sarah Black was the only plant infected (it never spread). And I am pretty certain there were lesions on the stem. The lesions never did develop the white spores shown further down in the above link.

So I am still confused. It looks like late blight, but never spread from the Sarah Black, and the Sarah Black was very productive right up until the first frost. So, I guess I will continue to closely monitor my Couilles de Taureau and see what happens to it.

[shlacm]

Okay, I Googled late blight in Virginia, Central VA, and even my town... read information on VATech's website... and it seems that late blight is rarely a problem (if ever) around here. So, I'm wondering if sun damage could cause damage resembling late blight... because I think I burned the plants spraying them late morning last week.

[Mark0820]

Originally Posted by carolyn137

If it were me I think I'd check all other plants first, then if nothing, blast those lesions with Daconil, your Ortho product, and watch it closely.

Best I can do but the final decision, as always, rests with you.

I can tell you that Couilles de Taureau is a really nice variety, but that shouldn't sway your decision b'c there's always next year.

Again, Taryn knows that LB has been in her garden and you say that it hasn't been in yours, and to me that's a strong point to consider especially with only one plant affected, to date.

Carolyn,

Thanks for the good advice! I blasted the lesions 2 or 3 times during the rainy period we had, and now that the weather is dry, the symptoms have cleared up.

I don't see any new lesions on the stem or any new spots on the leaves (I removed all of the lower leaves that had a few spots). I will continue to watch this plant closely, but right now it appears everything is going to be just fine, and I will be able to taste that really nice variety; Couilles de Taureau .

[Jeannine Anne]

Last year I grew most of my own but bought 4 large plants as I was late starting. Fortunately they went into a different area than the others and in pots not the ground, it took very little time for the trouble to show on those 4 and we got them out straight away, we were very lucky.

I did go back to the shop and tell them..Tania,it was the timber/garden shop kitty corner to Coquitlam centre.. the R... shop. They were very kind and refunded without a murmer and they admitted they has had problems in the shop stock which they returned to the vendor.

I will not buy in plants anymore, and it was so fast.

XX Jeannine

[Mark0820]

I guess I spoke a little too soon. I found 2 new small lesions, but whatever disease it is, it appears to be under control and spreading slowly at this point.

[Mark0820]

I can finally make an accurate diagnosis. I have early blight. This isn't too surprising since I have it just about every year. The stem lesions sure did look like late blight when I first saw them, but the leaves indicate it is early blight.

[shlacm]

Originally Posted by Mark0820

Well maybe I do have late blight. I found this link:

http://www.longislandhort.cornell.ed...ato.htm#images

The third photo down labeled "leaf lesions due to late blight" looks very much like the leaves on my Sarah Black last year (only the spots were much smaller than what is shown in the photo). There were black spots on the leaves before they turned brown and crunchy.

However, last year I didn't spray for disease at all, and Sarah Black was the only plant infected (it never spread). And I am pretty certain there were lesions on the stem. The lesions never did develop the white spores shown further down in the above link.

So I am still confused. It looks like late blight, but never spread from the Sarah Black, and the Sarah Black was very productive right up until the first frost. So, I guess I will continue to closely monitor my Couilles de Taureau and see what happens to it.

At this link, about halfway down the page - the 3rd picture up from the first pic of infected fruit - is a picture of stem lesions with the caption: "The brown spots on this tomato stem (below) are probably not due to late blight."

But it doesn't say what it might be... any thoughts/suggestions?

[carolyn137]

Originally Posted by Mark0820

I can finally make an accurate diagnosis. I have early blight. This isn't too surprising since I have it just about every year. The stem lesions sure did look like late blight when I first saw them, but the leaves indicate it is early blight.

Which is what I would expect.

Early Blight ( A. solani) can also cause stem lesions.

And I've never heard of a situation where just ONE plant amongst others has either Early OR Late Blight b'c both are transmitted by wind and embedded in rain drops so it would be rare to see just ONE plant infected.

The first indication of LB is a downward bending of the petioles, then development of the leaf lesions, which are NOT spots, rather, large areas of water soaked looking gray areas.

[lurley]

Its what I'm dealing with too Mark, I've never had to spray before, it has to be from the non stop rain we have had all spring.

Sent from my X10a using Tapatalk

[Mark0820]

If I am remembering correctly, I think I have read on Tville that PL plants tend to resist disease better than RL.

This is my first year planting PL plants, and I must say they are handling the early blight much better than the RL plants. On the PL plants, there are just a few spots on the very bottom leaves. On the RL plants, the early blight is spreading much more aggressively. It is interesting to see the difference in the two types of plants.

[grizlbr]

I just had a storm knock my plants down. Seems to be just below a tie up cord? Did a little weather bruise the plant and it grew a ways?

[grizlbr]

I pruned all bottom leaves and pulled tomatoes 16-20 from the Early girl and topped at 6 feet.
Hoping it is just my water is too Alkaline switching to an acid fertilizer. And not a Manganese deficiency?

[gourmetgardener]

If you have late blight, the Fungicide Quadris works wonders on it. It is a strobilurin fungicide, a synthetic derivative of a fungicide derived from wood fungi. It has both protective and curative effects. If you don't have disease, but have a neighbor with diseased tomatoes, it is a good idea to use a protective fungicide containing mancozeb.

[carolyn137]

Originally Posted by gourmetgardener

If you have late blight, the Fungicide Quadris works wonders on it. It is a strobilurin fungicide, a synthetic derivative of a fungicide derived from wood fungi. It has both protective and curative effects. If you don't have disease, but have a neighbor with diseased tomatoes, it is a good idea to use a protective fungicide containing mancozeb.

I can't speak to any other US states or countries, but here in NYS last I knew Quadris and Tatoo and similar could only be purchased by someone who held a pesticide license, but see below.

The main preventive for Late Blight that's suggested is Daconil, the 29.6% concentrate to be diluted, and then either Mancozeb or a copper containing prep.

http://vegetablemdonline.ppath.corne...ed%20Rates.pdf

Only Quadris Opti is listed as helpful for Late Blight (P. infestans) in NYS and Cornell is one of the leading centers for info on LB in the NE and has already put out an alert for same for this season.

Maybe Quadris is OK for folks to use without a pesticide license, I didn't check that, but if you go to the Syngenta website or similar for Quadris I think you'll see that it's sold in gallon amounts for several hundreds of dollars which I know I can't afford, not being commercial.

Hope that helps.