Is this little thing really what's destroyed my gardens?

[z_willus_d]

Steve, I'm on board with your analysis one-hundred-percent. I'm going to try and locate some kind of sulfur to spray the plants in the evening tomorrow. If I can't save the worst, perhaps I can protect the others. My records show that I sprayed with an oil-based product (Neem) on the 20th of May, about 2 weeks ago. I don't feel I should wait on this one, since I believe it is what took my entire garden out in the matter of two weeks last year.

Of course, it is possible that the neem was protecting my plants somewhat, since I haven't been using it for a couple weeks and now suddenly the problems seem more obvious. But, I do know the Wes and Heshpole and a few others were exhibiting signs of "yellowing" even before when I had been spraying neem more regularly. What's happened is I've added all kinds of additional sprays to my rotation, and it's forced neem to the back-burner (or rather I have to get through eight different products before I get back to neem), and that can take a couple weeks.

Lyn, I'm a huge admirer of your garden-houses. I'm sorry that you're facing this problem, and I hope we can all find a way to manage it so that we can maintain healthy, productive plants through our long CA seasons.

Steve, as I said above, thank you for your great help.
-naysen

[dice]

What happened to the thrips diagnosis? That seemed reasonably
likely to me. According to this page,
http://pubs.ext.vt.edu/444/444-281/444-281.html
thrips are attracted to flower pollen, but feed mostly on vegetation
rather than pollen. If that vegetation is in your flowers (pistil, style,
anthers, etc), I would expect that to lead to blossom drop.

You can find out if you have a thrip infestation with blue sticky traps.

Unfortunately, most of the biocontrols for thrips listed on that page
seem to operate best when humidity is 60% or higher, which would
be pretty rare at this time of year in your part of the country.

[z_willus_d]

Hi Dice, I have no question that I have a constant thrips infestation. I've been doing my best to fight them with organic sprays for months now. I know what the damage looks like that thrips can bring. While they can vector viruses, I don't think I'm dealing with that in this case. I believe this is an issue separate from the thrips problem. I realize that the post label here is misleading, since I was focused on bugs as the source of my issue last year (at least at first).

Steve, I've been researching sulfur and several sites suggest the flowable versions are more effective than the wettable and dust. I can't find it for sale anywhere, however. Can you point me to where you procured yours?
Thanks,
Naysen

[beeman]

Originally Posted by z_willus_d

Hi Beeman, Here's a pic from last year of the roots of one of my plants that went down to this problem:
http://www.tomatoville.com/attachmen...3&d=1338436905Thanks,Naysen

On the strength of that photo I would say not Corky Root Rot. But having said that, it does start off slowly, so I would look out for it when you decide to remove them at the seasons end.

[Heritage]

Lyn, thanks for the input and the heads-up on Zolotoe Serdtse. I did notice some yellow inside the canopy of ZS plants, so it looks like I'll spend today going through all of my determinates and thinning out some of the foliage for added air flow and yellow leaf removal.

Naysen, I bought a 50 lb. bag of 'Thiolux' about 10 years ago. I will be using the last of it tonight when I spray, so I will also be in the market for a 'micronized sprayable sulfur'. If you happen to find a suitable/similar product, in a smaller quantity, please post.

One thing I can never figure out when I spray sulfur: Instructions usually say something like "do not spray when the temperature exceeds 90 degrees" but some instructions say "if the temperature is expected to exceed 90 degrees". The second seems to imply you can't use sulfur if the temperature is going to exceed 90 during the next several days and would effectively eliminate the use of sulfur during the summer. If anyone knows the correct interpretation as it applies to tomatoes I would appreciate it.

Steve

[LDx4]

Steve, how long do you wait after spraying Neem to spray the sulfur? I spray Neem on a regular weekly schedule, so if I have to wait a month to spray sulfur, that will be a long time to go without spraying for other problems.

For my garden, I've found that the mildew usually lets up by mid/late summer, when it gets drier and hotter around here. Ironically, the best weather for healthy plants occurs in Oct/Nov for me -- I have no fungus issues at all with plants started late in the season. But fruit production is way down with the diminished sunlight hours then.

Also, this mildew is an equal opportunity disease -- it affects both OP and hybrids in my garden. This is one of the reasons I haven't jumped on the grafting bandwagon yet. If grafted plants get this stuff just like regular plants, I don't know if grafting will be worth the effort for me.

Lyn

[z_willus_d]

Originally Posted by beeman

On the strength of that photo I would say not Corky Root Rot. But having said that, it does start off slowly, so I would look out for it when you decide to remove them at the seasons end.

I certainly will. I'll also be looking for signs of F/V in the stems, as well as RKN in the roots.
Thanks,
Naysen

[z_willus_d]

Steve, thanks for the information. I'll get to searching. I do hope that temperature requirement only applies to the day of spraying. I guess if it also applied to the dry dust as well, we'd have a problem, since that would suggest that any sulfur residue in high heat on the foliage can be phytotoxic. I'm hoping it requires both the sulfur and the water component in the heat and with sun radiation to cause issues.

BTW, in my search I found that Potassium Bicarbinate is supposed to be helpful against powdery mildew. I already had purchased a product for this a couple years back, Green Cure. Here's a link to the label:
http://www.greencure.net/greencure_label.asp

Unfortunately, studies suggest it is only "moderately" effective and can not clear the issue. Davis lists it as acceptable as an organic solution here:
http://www.ipm.ucdavis.edu/PMG/r604100111.html

Note, Davis also lists Sulfur as a "partial control" solution:
"COMMENTS: Provides only partial control even when applied early. To prevent injury to the crop, do not apply within 2 weeks of an oil application."

I guess you have to graduate to the $1000 dollar a jug AZOXYSTROBIN chemicals to truly gain systemic mastery over this.
-naysen

[z_willus_d]

Oh, one good thing about the Potassium Bicarbinate (Green Cure) is that it doesn't have the same limitations on spraying w/ oil as Sulfur. So Lyn, that might be one potential stop-gap measure you could take. I'm going to water my plants with Aspirin water this morning, hoping it will help boost their immune system, as if they're not already amped up.

[Heritage]

Lyn, I have never sprayed oils and sulfur closer than 3 weeks apart so I've never really tested the limits. The last couple of hot, humid days have greatly increased the amount of mildew I'm seeing. It will be an interesting June.

Steve

[Paradajz]

Originally Posted by Heritage

...

Naysen, I bought a 50 lb. bag of 'Thiolux' about 10 years ago. I will be using the last of it tonight when I spray, so I will also be in the market for a 'micronized sprayable sulfur'. If you happen to find a suitable/similar product, in a smaller quantity, please post.

One thing I can never figure out when I spray sulfur: Instructions usually say something like "do not spray when the temperature exceeds 90 degrees" but some instructions say "if the temperature is expected to exceed 90 degrees". The second seems to imply you can't use sulfur if the temperature is going to exceed 90 during the next several days and would effectively eliminate the use of sulfur during the summer. If anyone knows the correct interpretation as it applies to tomatoes I would appreciate it.

Steve

hi, Steve,
sincere respect for your way of reasoning from my part

the correct word would be ''expected'', but it's just a general warning.
the use of sulfur at high temps has progressed ( although 10 years is quite a long period ), so 10-12h of suitable temperatures should do just fine. in practice it was shown that far more cases of fito- toxicity caused by sulfur was done by incorrect dosage of the stuff than high temps, and these days there is even quite a number of sulfur products that has such particle's size and formula that in appropriate doses those are considered temperature unrelated.
so one should just be carefull on doses and use it at appropriate time.

br,
ivan

[Paradajz]

Originally Posted by Heritage

Naysen, with that, you've moved me back into the Powdery camp. There are two different Powdery Mildews and the one we're talking doesn't have the fuzzy white growth:
http://ag.arizona.edu/plp/plpext/dis.../tomato/pm.htm

The high humidity inside the plant canopy would be ideal for mildew and the thick growth probably kept your preventative sprays from protecting the leaves.

Any sulfur formulation labeled for tomatoes and powdery mildew should help. I know you are aware of the caveat "do not spray when it's hot (>90F, especially if low humidity) or use sulfur if you have used oil sprays in the last 2 weeks (some say a month)". I sprayed my worst looking row of plants tonight with flowable sulfur. It's amazing how fast that yellow creeps up the plants.

As far as other organic fungicides for mildew, I have had good luck with Neem, but I know that is in your spray arsenal already and not been a great help. I would also like to know of an alternative to sulfur, maybe Paradatz, or others, can suggest an organic cure?

Steve

sorry, but one could say that the only organic cure for for L.T. caused mildews is not to get it

also, sulfur is a preventive with L.T. ( in addition to being an excellent acaricide ), but it won't stop the disease, only systemics like triazol ( penconazole, difenoconazole, etc. ) and some others actually can.
please also note, sulfur products might/will have some negative effects on ability of a flower to turn into a tomato.

but, eventually, if you had a L.T. problem on tomato, outdoors especially, you wouldn't have to worry about it that much: usually the bugger gets into control by weather on its own, with no required steps from your side- 25C almost stops it, 30C is a baricade it won't pass. ( sorry, short on time and having troubles managing with F-scale ).
anyway, outdoors it can produce significant damages only if the plants are very very very weak and/or overdosed by nitro. again, in such a case it if wasn't for L.T. to get it something else would, so one shouldn't worry about it just the same.
but, in this case, his plants aren't weak, just the oposite

[z_willus_d]

Ivan, I appreciate your inputs and expertise. From what I've read on the university sites, you're right about prevention being the only organic solution. I differ in your conclusion that I should not worry about the problem. Assuming L.T. is indeed what I have, and that seems quite likely (though I'd like to confirm), I know from experience that it can destroy a healthy vine in the matter of weeks. I know from experience last year in the same garden, that as the heat rose, my plants went down fast. I realize that the heat also acts as a barrier for further infestation, but I must already be largely infected. Ironically, last year as the Fall season came on with cooler temps, I noticed many of my seemingly dried up and dead vines were able to recover somewhat, put out new shoots, and power on. However, it was too late in the season for any of the fruit that set around Nov to actually mature.

In effect, this condition resulted in my gathering really only one or two rounds of harvest from my indeterminates. Harvest from very sick plants that were already half-"dead" of tomatoes which set when the plants were healthy. I wonder what effect that had on the taste/quality of the tomatoes as well.

I suspect I may do better this year with the grafted vines, but I don't feel I can just ignore the problem. My estimate for average lb of yield per vine (2' square space) was about 5lb or less. I would like to be 30+lb.

Thanks so much.
-naysen

[Paradajz]

Originally Posted by z_willus_d

Ok, lots of good stuff here... I love the deep dive into details.

First, let me thank Paradajz for the contribution. On the question of Verticillium, I will say that was one of the systemic diseases that I focused on heavily last year, along with Fusarium. I, ultimately decided that Verticillium was even less likely than Fusarium given the climate here, the low incident rate of V, lack of any darkening signs in the stem, etc. Now this year, since I'm grafting onto Maxifort, that seems even less likely. The Johnnies lists Maxifort with the following resistances:
* F2 Fusarium Wilt (Races 1 & 2)
* FOR Fusarium Crown and Root Rot
* N Nematodes
* PL Corky Root Rot
* TMV Tobacco Mosaic Virus
* V Verticillium Wilt

So with the "V" it would seem less likely than even last year that I have Verticillium. I will say that the look of the leaves does quite mimic that of V, which is why I latched onto it before.

Steve, I mainly grafted onto Maxifort, and a small handful got Beaufort. I note that some of the regular leaf types just seem to turn yellow, while the larger potato leaves have the characteristic yellow splotches, turning to necrotic brown.

Something else I noticed this evening was that the yellowing mainly appears within the cover of the plants outer foliage. That is to say, the outermost leaves and branches show the problem less than those within. That's not a rule, but it does hold sway. I also noticed that this same problem seems to be hitting my peppers now as well as the tomatillo plants (actually, I first noticed specific leaves turning yellow on the tomatillos several weeks back.

To the question of disease progression, I would comment from recent experience and last year that it seems to appear first on plants that have been out in the garden for the longest period of time, hence also those which are generally most mature. It seems like I notice it first on a single plant, but then a couple weeks on it is apparent on numerous. I think that in the matter of a couple days it went from not that noticeable to very noticeable on a few. On others it's been an escalating progression. For instance, my Wes was showing it weeks ago on the lowest branches, but not it's 65% consumed to within a quarter of the top of the plant. The older branches and leaves have turned to brown dust.

Frankly Steve, I'm really inclined to thing you hit the nail just about on the head. It would jive with what I've read about the mildew; the fact that I've been spraying so moist under leaves; that I let my plants bush out, so they're quite compacted in their cages. The only thing I don't really notice is the white fuzz and sporulations, though perhaps given the hot dry climate here, they can't quite coalesce to that stage.

I'm zeroing in on a couple products. Comments?
- http://www.domyownpestcontrol.com/hi...ay-p-2325.html
- http://www.amazon.com/BONIDE-PRODUCT...eywords=sulfur

I wonder, besides the sulfur, if there's something else I should try. It seems that sulfur will deter the mildew, but it is hard to impossible to get rid of. I feel that quick action is required here, and that time is of the essence."

Thanks all.
-naysen

( oh is this a long quote or what... sorry all )

hi, N.,

i also like the way you reason with the details very much.

short on time, so i'll try as shortly as possible: this is V. if i ever saw one
( actually, the only other thing i know of which produces such type of leaf necrosis is a very rare type of bacteria which is totally uncommon for solanaceas, and better not to talk about it since it's far worse that verticilliums )

tell- tell signs:
* do not think that the discoloration of a steam is a must, very often you won't be able to see it, what ever you've read about it. there is like a zillion reasons for it: even when noticable it's standardly extremely light, pink, rose, light- brown, even slightly darker green than xylema itself; there is a huuuge number of strains with extremely different levels of pathogenicity, which in combination with tomato sort, plant strenght, weather conditions in past and present, nutrients levels.... well, it's an abnormal number of possible outcomes, out of which each one can produce different visible symptoms
* ''V- resistant'' doesn't actually means 100%, it's actually an average capability of a sort to resist a certain villain
* when you compare L.T. and V. chances, analyse the reason for leaf chlorosis:
- with L.T. chlorosis appears around the spot where pathogen feeds and develops ( this place appears as a necrotic spot ), in other words chlorosis is caused by it. eventually, this chlorosis will be definite- bordering the spot where pathogen ''works'' with clear margins. it will be only in the terminal leaf stage that you won't be able to tell the margins of chlorosis, just as with about any other disease.
- with V. chlorosis is caused by toxins which the pathogen produces ( the place where it does it is xylema only at the beginning, later the bugger likes to spread to wider territories ) and the weaker ability/or dissability of a normal fluid flow, which with a tomato plant always tends to appear visible at leaf tops as necrotic burn- spots ( toxins ) and fire- like indefinite chlorosis ( sounds familliar ). there isn't actually that large range of pathogens which can induce indefinite chlorosis.
* cold is a word for V., but it actually needs no more than 24h of cold ( 21-27C is the ideal cold for it ), and it actually needed it some 30-45 days ago when the pathogen in my opinion found the way into your plants.
* ''V- shape'' as the most famous tell- tell sign doesn't actually have to be that often, depend on zillion things, but again- the sole presence of it is a street to look into.
* typical V. appearance time is when the plant is intensively setting fruits- which is late, far after the pathogen entered the host. this works for tomatoes mostly. only very weak or mechanically damaged seedlings will stop growing and dry- out quickly after planting.
* ''droopy'' leafs appearance is a clue.
* initial appearance at higher, partial or midd- sections of a plant is also a clue.

sorry, wanted to add some more but out of time
anyway, in my opinion you actually have just about all signs of V. there, just haven't found the most reliable one yet. still, my advice to you is to test one of those plants.

br,
ivan

[Heritage]

Ivan,

Great points, it's nice to have an expert's opinion. If I get a chance I'll post some contributory photos tonight.

Steve