Septoria leaf spot--what to do?

[applestar]

...(not sure about K)

...I had to find out

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.

[applestar]

In Subject: Disease on black cherry tomato plants

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.

[applestar]

Also dug up this interesting excerpt from the 34 page Aerated Compost Tea thread

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.

[applestar]

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?

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.
Get Access
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

[rainbowgardener]

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

[applestar]

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: https://www.helpfulgardener.com/forum/vi ... 12#p340812

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.

[Juliuskitty]

...(not sure about K)

...I had to find out



[/quote="applestar"]- so maybe there IS a reason to use 2% milk which was the original recommendation in the grape industry.

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!