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jemsister
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Septoria leaf spot--what to do?

I think my tomato plant seems to have early stages of Septoria Leaf Spot. It looks a little like this (not actually my photo):

Image

My question is, is this going to ruin my fruit? Should I pick what is blushing now before the fungus spreads?

Also, I understood that it usually starts at the bottom and works its way up, but in this case it is mostly on the middle and upper leaves...?

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gixxerific
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Septoria does not effect the fruit. But it will continue ass it is hard to control. And by control I mean lessen the damage, you will no get rid of it. You should rotate out for 4 years in a real world. In my world that is not feasible so I do what I can. I had it bad a few years back but still got a good crop. I just kept taking off the lower limbs it was ugly at the years end but the plants never died and I got fruit till the end. Seeds can be saved without fear.

You could spray with a fungicide and remove dead or dying limbs, that will help slow it down. Let me see if I can find my pics of them, you will see how bare they were yet still kept me afloat.

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jemsister
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Thanks, Gix. I picked off all the leaves I could find, and I sprayed it down with a copper spray. It started showing a few small brown spots here and there, but was pretty much doing great. Then we had a few days of rain, and today, as the sun came out, I saw the yellowing. :( I'm glad to hear that it doesn't effect the fruit though. Going to try to keep it in check as long as I can, hopefully I will still get a good crop. Going on vacation for a week, but Hubbyman has instructions to pick off any bad leaves while I'm gone. Hope he remembers!

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jemsister
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These are pictures of my own plant.
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My tomatoes got hit hard and fast this year and after a lot of research, this is what it looks like. The plants are spaced 2 feet apart and are like 6 feet tall. I only have 6 plants.

Half the plants are gone because kept ripping off the lower limbs, then the middle limbs and all that is left are sticks with some leaves that haven't got hit yet at the top and a lot of dead leaves/limbs in the middle that I just can't reach right now. UGH! So far the fruit still looks okay, but it is still green. I was glad to read it doesn't affect the fruit.

Thinking about next year - I too cannot move the location as I have very limited space - but I am thinking of spacing them even further apart with a much wider "cage." But that will mean I would only be able to have like 4 plants. If they had more space, do you think they would grow even bigger and produce more fruit to make up for the 2 less plants I will have?

Also, would the "VF" seeds or something like that I've seen that are supposed to be disease resistant work? I wouldn't be able to have the variety I have now, but it would be better than have dying plants. Has anyone tried those seeds that are supposed to be disease resistant? Do they really work?

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I find that when I get fungal diseases of any kind, on tomatoes, peppers, basil, cucurbits, I am ultimately not going to win especially in my humid climate. I try to start an anti-fungal preventive program when the weather conditions are favorable for fungal growth and try to prevent the problem before it starts, select for resistant cultivars, provide more air circulation, and if more than a couple of leaves are infected, I know when it is time to pull them out. It is important to pick up all of the leaves and debris as the fungal spores can survive on the dead matter. I also have a climate without winter to kill anything off, so cultivar choice, preventive measures, early detection, and removing the infected plants are my best defense.

I have not had to rotate out of a crop for fungal disease except for basil, but I have had to destroy a whole batch of plants before. The only time I had to rotate crops were for viruses and basil downy mildew.

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rainbowgardener
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Spacing the plants farther apart should help with the disease issues. Whether it will make up for having four plants instead of 6, I don't know, but it will be better to have 4 plants than none, because they died of disease.

It also helps from the beginning to take the bottom leaves off, so that nothing touches the soil. You also want to mulch well, so that soil can't be splashed up on to the plants. I think it helps along with removing suckers, to remove some of the interior branches, so that the plant has good air circulation.

Fungicides work better preventatively than as treatment. Organic fungicides include baking soda solution, diluted milk, hydrogen peroxide (but pick one, they can't be mixed, but you can alternate treatments, they need to be reapplied every couple weeks or after rain). Start spraying before you see any disease signs.

The disease resistant varieties are only resistant to certain diseases. That is what the initials tell you - V is verticillium wilt and F is fusarium. I don't think I have seen any septoria resistant varieties. But septoria in my experience is about the least virulant tomato disease. Tomatoes can survive and keep producing despite the septoria, much better than they can with the blight or wilt diseases. I have found like gixx was mentioning above, that if I keep taking the diseased leaves off, by the end of the season they are looking pretty bare on the bottom, but they are still producing.

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Please, I have heard other people say to use milk for fungus too. How does milk stop fungus?

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The lactobacillus in the milk attacks the fungus.

"Lactic acid bacteria are known to produce various antimicrobial compounds that are considered to be important in the biopreservation of food and feed. Lactobacillus rhamnosus L60 and Lactobacillus fermentum L23 are producers of secondary metabolites, such as organic acids, bacteriocins and, in the case of L60, hydrogen peroxide"
https://www.ncbi.nlm.nih.gov/pubmed/22497448

So it helps to let your milk sit out for a little while before you use it as a spray, maybe even stir in a spoonful of yoghurt with active lactobacillus cultures and let it sit a little. That way you have more active lactobacilli. You don't want to let the milk sour, just come up to room temp and get the bacteria active again.

I thought the above was interesting that the lactobacillus can actually produce hydrogen peroxide, which is another of the anti-fungal agents we recommend.

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That is fascinating. Thank you. I was afraid the lactose in milk would feed microbes, but that makes perfect sense about the LA.
That is what is so great about this forum, the learning. Many thanks Rainbowgardener, I am going to try it this season, because I can depend on the fact that their will be fungus!

SLC
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Here are pics of my tomatoes - I am sooooooooo angry cuz yesterday I sprayed them ALL with that Organic Copper Spray and soaked them like it says to do and used almost the whole bottle that wasn't that cheap, and then we had a thunderstorm last night!!!! UGH!!! :evil:

This does look like this Septoria Leaf Spot, right?

Here is a pic of my poor tomato plants:
Tomatoes 2 smaller.JPG
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And here is a closer one so you can see the leaves and the fruit behind that still looks good (and hopefully stays that way!)
Tomatoes smaller.JPG

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rainbowgardener
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yes gardeners need to always be very tuned in to the weather reports. Sometimes you can still get surprised, but watching the weather reports carefully helps with knowing when to plant, water, spray, etc.

Does look like probably septoria. All those dead leaves should be removed and trashed (not in compost pile) and as much as you can of the spotted leaves without defoliating the plant. Then see all the suggestions above.

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I agree. I don't like to let fungus infected leaves hanging over the fruits to easily drop/spread spores AND block airflow.

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applestar
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Juliuskitty wrote:Please, I have heard other people say to use milk for fungus too. How does milk stop fungus?
Truth is this particular technique appears to be controversial among the scholarly articles.

There are different reasons given when you look around. Some scientists even debunk the concept, and some scientific articles say it's a myth. Some say it works to prevent only some fungal disease and not others. Yet I have used it on all kinds of plants and found it to be effective in varying degrees. I think it IS best used as preventative, and that's what makes it difficult to quantify. (If fungal disease doesn't or only minimally appear after spraying diligently, is it because you sprayed or is it something else?)

- The first I've heard about it was based on its use on grapes -- I think this was in NAPA valley and in Australia.
- I've also read an article stating that dipping hands in solution of powdered milk to make up 30% MILK PROTEIN is effective for preventing spreading disease if used to dip hands in between touching diseased tomato plants. If I remember correctly, it wasn't fungal disease this article was talking about but some kind of virus, which I found interesting.
- I have read that definitive proof came from an article from a South American research on a non-tomato plant... a cucurbit, I think

I think I've posted the actual links to these articles somewhere before. I'll try to find them later.

My first understanding was that the lactobacillus would act as a shield by coating the leaves. Like all bacteria, they create biofilm which help them stick to the leaves and grow into the pores even when it rains, so unlike chemicals they won't be easily washed off. Their presence makes it more difficult for fungal spores to take foothold. Lactobacillus has it's own set of fungi that prefer to grow in it, those fungi will compete with fungi that are inimical to the plants for the space on the leaves. If they have spread their hyphae on the surface of the leaves, there is no room for the fungi that feed on the plants to take hold or grow (or they have to first fight for that first foothold).

This is where you discard the idea that you must kill/stop ALL fungal activity in order to save the plants. You are fostering biodiversity on the phyllosphere.

This is why I like to alternate milk spray with AACT.


In addition to or as opposed to the lactobacillus directly being fungicidal, one university research concluded that it's the milk protein that is effective in killing the fungal spores and the milk spray should be applied in presence of sunlight. -- Reading that gave me a pause because I had been concentrating on NOT spraying in direct sunlight. After some thought, I decided to continue choosing overcast days and even imminent gentle (not downpour) rain days and sundown to spray with milk. This has worked for me so far. And I think particularly with furry plants like tomatoes that can soak up and hold the solution and end up increasing the concentration in the sun, it's best to avoid spraying anything when the solution can dry up quickly (sunny, windy, ...). In fact I tend not to spray the milk solution on dry plants.

I think that thoroughly spraying top and bottom of the leaves also means significant amounts fall to the ground, thereby increasing the lactobacillus count in -- and enriching/feeding -- the soilfoodweb, which also would be adding to the plant's health and strengthening their immune system. I would think analysis of the milk solution should indicate a certain level of N and P (not sure about K), as well as minerals and other micronutrients, so you are effectively foliar feeding and soil drenching the plants as well.

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applestar
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applestar, in the last post on previous page, wrote:...(not sure about K)
...I had to find out :wink:

This isn't a definitive source, but it will do for this purpose:
The amount of potassium and sodium in milk decreases as its fat percentage increases. For example, a 1-cup serving of 2 percent milk contains 224 milligrams of phosphorus and 342 milligrams of potassium.
https://healthyeating.sfgate.com/much-po ... -4745.html

-- so maybe there IS a reason to use 2% milk which was the original recommendation in the grape industry. :o

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applestar
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In Subject: Disease on black cherry tomato plants
applestar wrote:You could try removing all wilted/dead foliage and spraying with milk, AACT, or your choice of fungicide. I have also read that soaking your hands in 35% protein milk solution helps to prevent spreading diseases by handling. That's what I did.

In the linked publication, the brief reference to use of 35% milk protein solution is in the section for Tomato Mosaic Virus and recommends spraying the seedlings too.

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applestar
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Also dug up this interesting excerpt from the 34 page Aerated Compost Tea thread 8)
rainbowgardener wrote:I went looking to see what I could find and immediately found this article on research done by Rodale Institute in conjunction with Penn state U

https://newfarm.rodaleinstitute.org/dept ... /tea.shtml

Summarized it says that ACT was effective treatment against powdery mildew in grapes, but not in pumpkins. In their potato patch there was not enough disease present to be able to show any results.

HOWEVER:

"The spuds did show a yield response to compost tea applications, however. Plants receiving regular doses of compost tea produced larger, better potatoes than both the nutrient-ingredient-only and the untreated control plants. Marketable yields in the compost tea plots were between 18 and 19 percent higher than in the untreated plots and about 15 percent higher than in the nutrient-only plots. Compost tea-treated plants also produced tubers that tested higher for a range of nutrients, including iron, boron, potassium, and manganese. Iron showed the biggest response, with levels an astonishing 1700 percent higher in plants receiving compost tea than in untreated plants."

To me that sounds HUGE. Especially in comparison to the nutrient only control group, where they worked on giving the plants all the same nutrients that the ACT would provide, without the ACT/compost. And still the ACT treated plants had 15% higher yield. So more, bigger, and more nutrient rich potatoes with ACT!

So what do you all that are using ACT think: are you using it primarily to prevent/treat mildew and other diseases or primarily for fertility/ nutrient benefits? What do you know of scientific evidence for the benefits of how you use ACT?
That thread is crammed full with really valuable information -- I really recommend at least skimming through it, and even poring over it. I haven't looked through it in a while so I might just do that myself. :D

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applestar
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Last one... well, two :()

I found a PDF "final report" of that Australian grape research:
Applications of milk and whey generally increased the population of indigenous bacteria, yeasts and filamentous fungi on leaves and bunches, compared with vines treated with sulfur, but had no obvious effect on species diversity. While increased microbial populations may contribute to the reduction of powdery mildew on the vine surfaces, there was no evidence that they impaired grape or wine quality.
In summary, when disease pressure is low to moderate, commercially acceptable control of grapevine powdery mildew on cultivars that are not highly susceptible can be achieved using a range of novel materials including milk, whey and mixtures of canola oil plus potassium bicarbonate. As these compounds act as contact fungicides excellent cover of leaf and berry surfaces is required for effective control, and spray intervals should not exceed 14 days during flowering, early berry development and periods of rapid shoot growth.
https://research.agwa.net.au/wp-content/ ... report.pdf


I also found this if anyone wants to buy it and give us the highlights. Does it imply you should spray hydrogen peroxide in conjunction with the milk spray? At what %? Simultaneously or prior to milk? 8)
Australasian Plant Pathology
September 2006, Volume 35, Issue 5, pp 487-493
Mode of action of milk and whey in the control of grapevine powdery mildew
P. Crisp, T. J. Wicks, G. Troup, E. S. Scott

$39.95 / €34.95 / £29.95 *
* Final gross prices may vary according to local VAT.
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Abstract
Grapevine powdery mildew, caused by the fungus Erysiphe (Uncinula) necator, is a major disease affecting grape yield and quality worldwide. In conventional vineyards, the disease is controlled mainly by regular applications of sulfur and synthetic fungicides and, in organic agriculture, by sulfur and botanical and mineral oils. Research has identified milk and whey as potential replacements for synthetic fungicides and sulfur in the control of powdery mildew. Electron spin resonance and scanning electron microscopy were used to investigate the possible mode or modes of action of milk and whey in the control of powdery mildew. Electron spin resonance experiments showed that various components of milk produced oxygen radicals in natural light, which may have contributed to the reduction of severity of powdery mildew on treated leaves. Milk and whey caused the hyphae of E. necator to collapse and damaged conidia within 24 h of treatment. Hydrogen peroxide, applied as a source of free radicals, also caused collapse of the hyphae of E. necator but did not damage conidia, and appeared to stimulate germination. Lactoferrin (an antimicrobial component of milk) ruptured conidia, but damage to hyphae was not evident until 48 h after treatment. The results support the hypothesis that free radical production and the action of lactoferrin are associated with the control of powdery mildew by milk.
https://link.springer.com/article/10.1071/AP06052

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rainbowgardener
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For some reason you removed my original answer that the lactobacillus has fungicidal effects. There is apparently a lot going on and it is a complicated situation. However I don't believe I was wrong. I gave a research citation about it, which I'm having trouble getting back to, which noted that in some situations (some strains of the bacteria?), the lactobacillus actually produces hydrogen peroxide.

There's also this:

Lactobacillus plantarum IMAU10014 was isolated from koumiss that produces a broad spectrum of antifungal compounds all of which were active against plant pathogenic fungi in an agar plate
https://www.plosone.org/article/info%3Ad ... ne.0029452

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Rainbowgardener you had me in a panic. I thought I had accidentally deleted it in the early morning fog.

I think you just lost sight of it in the shuffle: :arrow: https://www.helpfulgardener.com/forum/vi ... 12#p340812
rainbowgardener wrote:The lactobacillus in the milk attacks the fungus.
I think later when I have time, I will split off the discussion about effect of the milk as fungicide and make it a topic in the Organic Insect and Plant Disease Control, and leave a link for it here for reference. I think that would make more sense than what I did earlier which was to create a link to this portion of the discussion (PM me if you -or anyone- think otherwise or have other mod related recommendations).

I have no doubt your cited article also has merits and applies to the overall beneficial action of the milk spray, and I won't forget to include your post when I make the split. I was just trying to complete the picture, as it were, since I've looked into it many times, especially when asked to explain how it works, and when I come across or am pointed to debunking articles and citations.

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applestar wrote:
applestar, in the last post on previous page, wrote:...(not sure about K)
...I had to find out :wink:



[/quote="applestar"]- so maybe there IS a reason to use 2% milk which was the original recommendation in the grape industry. :o
Maybe nonfat milk would be even better, all the protein is there, and if less fat = more K than there you go. Apple this series of posts is a great education. Thank you for all the time and research on this subject. I brought this up on another forum and wasn't nearly as happy with the tepid response there. You are appreciated! :wink:



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