Name this malady...if you can

[z_willus_d]

Hi,

I've been fighting what I assume are various forms of mildew and fungus on my indoor (garage) garden for over a month now since the humidity kicked up (and the plants started to crowd one another). So, I've lost about 1/3 of the branches on 4/5ths of the plants (I have 12). Now the four or so plants that actually have some tomatoes growing on them are starting to go down, but with a slightly different malady to my eye. Their leaves curl up, dry up, and then turn dark. I've been spraying regularly with Daconil, but it hasn't seemed to help.

When I examine the underside of the afflicted leaves, I find that they have a white/pink/magenta ting of what seems powder (though it doesn't rub off) around and along the veins. The pics I've posted don't do a great job with the color (phone camera), but hopefully they'll spawn some ideas. I've devoted loads of time, not to mention $$'s on this indoor garden experiment, and so far no real results. My best hope is in keeping these four Rosella Purple plants living long enough for them to deliver something.

What can I do to fight this problem? Thanks for your ideas and help.

--naysen

[gnol]

It may be curly top virus.
http://aces.nmsu.edu/pubs/_h/h-106.html

A couple of my plants got it this season. They still produced as it was later in the season.
I've had it other years where the plant just stops growing and I've pulled them out.
Not the best picture but it is one from this season.

[VC Scott]

Perhaps leaf roll.

http://www.alltomato.com/tomato-diseases-leaf-roll.html

[amideutch]

One of the problems could be is stress. Why don't you use Actinovate and EXEL LG for your foliar applications versus Daconil. Daconil is a protectant and nothing more. With Actinovate and EXEL LG you will have a contact and systemic fungicide which is also Bio-friendly. For the stress aspirin dissolved in water and applied as a foliar works well as it will turn on the plants defenses to help fight whatever is bothering it. Ami

[bower]

Three known causes of purpling of leaf veins are: phosphorus deficiency, usually a physiological uptake problem due to cold soil; curly top virus; and tomato spotted wilt virus.
http://www.ext.colostate.edu/pubs/garden/02949.html
http://www.clemson.edu/extension/hgic/pests/plant_pests/veg_fruit/hgic2217.html

Since the soil isn't cold, a virus is more likely. Ami's suggestion to treat with aspirin (or another source of salycilic acid eg willow leaf extract) is a good one, if you want to give the plants a chance to develop resistance. I would add that culling and burning the infected leaves is a good idea.

The two virus possibilities are spread by different pests: curly top by leafhoppers, and TSWV by thrips. The necrosis of the leaves suggests TSWV is likely the cause, afaict. You can check for thrips if you haven't seen them by using yellow sticky traps.
Where thrips are endemic and beyond control, aluminum faced mulch has been found to reduce the incidence of the disease.
http://cat.inist.fr/?aModele=afficheN&cpsidt=5602118
An integrated pest management strategy pdf, which refers specifically to the present situation with TSWV in California, is linked at this page:
http://www.ipm.ucdavis.edu/PMG/r783102211.html
The IPM strategy document also has some better photos and descriptions to distinguish TSWV from other causes. This virus is fairly new on the scene, and infects a huge number of host plants, as well as infecting the thrips that carry it.

Another control measure that might work for your greenhouse situation : "Screening air intakes and using double-door entries have helped reduce incidence of TSWV by preventing the entry of viruliferous vectors into the greenhouse." This is among the management strategies reviewed and suggested, including the reflective mulch, at the site linked below, which also gives a very detailed overview of the virus itself and its lifestyle - it actually belongs to a family of viruses that infect insects, not plants (fascinating to the virus hunter..).
http://www.apsnet.org/edcenter/intro...ottedWilt.aspx

[z_willus_d]

Gnol, I suppose it's possible I got a virus. But why would it have only affected these four plants in this way, and only the Rosella Purples (not the four or five other dwarfs I have). How did I pick up the virus? I suppose it would have to have come from an insect vector. I do have a few fruit flies and white flies flying around the garage as I keep my worm bin in there too. I don't have an exorbitant number of insects flying around though. I have sticky traps and have actually used a beneficial nematode product called ScanMask that does a good job of eliminating the problem systemically.

Did the plants you had that were affected by the virus have a light-pink color to the veins as seen from the back side of the leaves?

Thanks,
Naysen

[z_willus_d]

Scott, common leaf roll is apparently due to over-watering and wet roots. I'm using Ray's InnTainers with their self-wicking media for watering. The media does keep moist, but it seems to work for a lot of folks without leaf-curl. Also, my leaves aren't leathery so much as slowly drying up and then becoming crispy and dead.

Thanks for passing on the idea.
-naysen

[z_willus_d]

Ami, I actually sprayed twice with Actinovate (as well as did a soil drench) when I first noticed the fungus/mildew problems onset. I didn't perceive even the slightest improvement, which was mightily saddening to me as I was looking forward to a true test of the Actinovate's strengths. It may be I have conditions that Actinovate just does not address, or perhaps the problem was just too prevalent. That's why I moved on to the brute force Daconil method, which I hate to do. It's true that Daconil has done nothing to "kill-off" or eliminate the problem, it just appears to slow it down. And I agree I may be stressing the plants with its nasty, milky lathering applications.

I don't have EXEL LG (can't seem to find it anywhere around here to buy), but it's actually next on my list of products to purchase for next season (outdoor). I'll look to purchase it online and pay the $10 shipping if I can't find it local.

Related, have you ever used Serenade for this purpose. How did it stack up against EXEL, Actinovate, Daconil?

What about Azoxystrobin and where do you purchase it?

Thanks!
Naysen

[z_willus_d]

Bower,

It sounds like you're money is on a virus. I appreciate all the links you've embedded, particularly the HGIC one, which I had not before seen. I think they've done a good job of summarizing a number of common maladies. That one went in the bookmarks.

I've had sticky traps out for over a month, and they have an assortment of 2 or 3 bugs. I need to examine them again for any evidence of thrips, which I assume based on the all knowing Wikipedia look like the attached pic.

It may not have been clear in my intro to the thread, that these plants aren't in a green house but rather under artificial light (LED and T5 Fluorescent) in my semi insulated garage. The number of organisms available to attack my plants should be minimal as the bins started with mostly sterile soiless mix. I write mostly because I also mixed in home-made worm-castings, which I'm certain include mites (Acarina) and possibly springtails (Colembola) though I've never seen the later near the bins. There are also fruit flies. In any case, I'll examine my six or eight traps for evidence of the thrips.

I'll also follow Ami's advice and try a foliar of asparin. Any guidance on the concentration levels for this would be nice. Also, can another Actinovate application marry well with the asparin, or should those be separated.

Thanks,
Naysen

[z_willus_d]

BTW- I read this about these mites in my worm bin. It suggests they're beneficial, though I'm not sure if they had plants and tomatoes in mind rather than the bin itself. I'd like to know if these types of mites (not sure they're spider -- probably not) can be a problem. You (or at least I can) just barely see them with the naked eye.

"Mites are among the most numerous inhabitants in the worm bin, with many different species feeding on decaying organic matter, fungi and other organisms. They are generally found on the surface of the bin, though some predatory species will venture deeper if the material is loose and there is a food source. While beneficial to the system for the most part, it is not uncommon for mite populations to become so large that they stress the worms. Infestation level blooms generally occur on the surface of the bedding and cause the worms to remain in the lower areas of the bin and to decrease their activity. Mite populations can be controlled by removing the upper few inches of bedding during an infestation level bloom, or by placing melon wedges, fleshy side down on the bedding. This is a favorite mite food, and they will soon collect on the melon, which can then be removed from the system. Leaving the bin lid open and exposing the bedding surface to drying and UV light will also control mite populations.

The vast majority of mite species in the bin are beneficial organisms which make up a significant part of the bin ecosystem. Mite species which damage living plants are not found in the worm bin. Control of mite populations should only be considered if the worms are demonstrating stress behaviors like refusal to come to the surface, huddling in a ball, low reproduction or mass exodus. What worms consider to be infestation levels of mites is often very different from the human view.

Mites are cousins to spiders and have large bodies, small heads and eight legs. Their colors range from mottled brown, to red, to glossy white. Species of mite found in the worm bin pose no threat to garden plants or people.
"

[maf]

It may just be natural leaf senescence. Rosella Purple has the gf gene so the old leaves do not turn yellow before death, instead they go directly to brown and dead, or alternatively fall off while still somewhat green.

I think your setup was 100% artificial light and some of the plants were 6 feet high now IIRC? The intensity of light falls off by a factor of 4 every time the distance from the source doubles, which is not a concern when the sun is the light source, but when using artificial lights, even high output ones, any leaf more than a couple of feet down in the canopy is contributing very little energy to the plant and will be sacrificed so that the energy stored in the leaf can be put to better use (as far as the plant is concerned) growing new foliage nearer to the light source.

[bower]

maf could be right - and the purple colour could be simply caused by diversion of the phosphorus from senescent leaves to the fruit that are forming - you did mention that the affected plants are the ones setting fruit. Setting fruit requires lots of P.

I found an excellent page about phosphorus uptake factors, which explains the physical reason for purple colouring:
"When respiration is restricted due to a P shortage, sugars are not converted into energy and they accumulate within the plant tissue. The accumulation of unused sugars leads to the purple coloration often seen with P deficiency. "
http://www.spectrumanalytic.com/supp...f/P_Basics.htm

There are also reasons other than cold soil, explained on that page, why phosphorus uptake may be restricted and limit respiration thus causing purple leaves. But the demand for fruiting is probably enough to explain it.

I'm assuming that the antifungal was used on all the plants, not just the fruiting ones, so it would not account for reduced P uptake due to adverse effects on the mycorrhizae (which can double P uptake in tomatoes).

Perhaps a side dressing of bone meal would supply enough P for the fruit formation and for all else, and limit the loss of leaves on your fruiting plants?

[amideutch]

Naysen, purchasing Azoxystrobin in Germany is no problem and can be done over the counter at most garden centers. But in the US it's a totally different story. About the only folks that can get it are commercial growers in commercial quantities. I even e-mailed the North American Rep of the company that produces it over here and no joy.

Normally 2 Aspirin tablets per gallon of water. Over here Bayer sells aspirin plus Vitamin C in tablets that dissolve in water like Alka Seltzer which is easier than dissolving tablets in water. Don't know if they are available in the US. For now I would apply aspirin and Actinovate at different intervals till we get a read from Boomer at Natural Industries. I asked Boomer the question about applying Actinovate and EXEL LG together and he said no problem.

The key is to use these products as a preventative as opposed to a curative. Don't wait till the plants get infected to act as eradication is a lot harder and not always successful. And don't forget the mycos as they can help with soil borne disease as well. Biota Max and MycoGrow Soluble make a pretty good team. Ami

[z_willus_d]

Originally Posted by maf

It may just be natural leaf senescence. Rosella Purple has the gf gene so the old leaves do not turn yellow before death, instead they go directly to brown and dead, or alternatively fall off while still somewhat green.

I think your setup was 100% artificial light and some of the plants were 6 feet high now IIRC? The intensity of light falls off by a factor of 4 every time the distance from the source doubles, which is not a concern when the sun is the light source, but when using artificial lights, even high output ones, any leaf more than a couple of feet down in the canopy is contributing very little energy to the plant and will be sacrificed so that the energy stored in the leaf can be put to better use (as far as the plant is concerned) growing new foliage nearer to the light source.

Maf-

Yes, I've noticed that the branches of the RP plants are prone to just jettison once the leaves have started to become necrotic. The other dwarfs don't eject their branches as readily. Yes, I'm 100% artificial right now, and these four RP plants are beneath the 8-bulb T5 HO fluorescent. They're up about 5' now. The plants under my LED light that I've given up on are over 6'. I'm going to dump them outside in the backyard and let them fend in the cold. It will get down to 35F at night but up to 60-70F in the day. I expect they're done for in any case. Just to show I'm not all that terrible a caretaker, I'll leave the aquarium heaters in their water reservoirs on the hope that extra heat to the soil and water will help them get through the coldl nights.

With respect to your comment about the light difference, I'd say that definitely the leaves and branches at the bottom canopy are dying off. They either get wilted, dark then drop or I aid them with my scissors. The leaves I'm concerned about actually are near the top of the plants and they are getting plenty of light, as can be seen in my pics. I don't think they're lacking for light at this time. No, it's something else that's afflicting them.

Thanks!
Naysen

[z_willus_d]

Bower, just following up on my earlier post about the thrips. I checked my sticky bug traps, and I didn't find anything that looked quite like a thrip. I had a few larger mosquito (the basssstards!), a couple white flies, but in the main plain old fruit flies.

To your comments about phosphorus deficiency, I think that's a heavy contender. I've actually gone out of my way to *not* feed the plants for over two months now, since I was having serious blossom drop issues on most (and all until recently with the RPs) of the dwarfs. I took care of any temperature concerns with aquarium heaters and a large oil-filled heater in the garage. Some folks thought I might have over-fertilized the plants, though I followed Ray N's tomato tone (slow release fert) recommendations, and I later added a little TigerBloom and 1/2 tsp of Calcium Nitrate. But... as I said, I've cut out all fertilization (other than the embedded TT) for over two months. Maybe it's time to apply the TigerBloom again to these four fruiting RPs.

Yes, I've applied both Actinovate (foliar and soil drench) and Daconil (foliar) to all plants equally.

I'll add some TigerBloom to the water reservoir of one of the two InnTainers that store the RP plants -- we'll see what happens.

Thank you,
Naysen