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derry n.h u.s.a.

THIS IS MY LAST RESORT for powdery mildew.I,ve tried ,daclinol,Mancozeb,Bakingsoda,neem oil,Bleach!,Copper,Caption ,Compass,to say the least my leafs are taking a beating.So i got a the phone with a couple other growers and came up with zero tolorance,Its and oxidizer,Fungicide unrestricted,it requires 1 1/2 ozs per gallon of spray,you drench the plants top and bottom leaf tubes and vines,you apply a three stage drenching,12 hours apart,some tried sump pumps but it goes to fast,so i used my pump sprayers ,took me 10 gallons to compleatly soak my 1000 sq/ft patch (2 plants) this was last night ,this morning got out their at 6.00 am sharp and applyed again,most of the white fungus or fuzzy spores had dissapeared,the second application even washed what white was left ontop of the leafs,undersides are harder to see!tonight the third application,took me about 2 hours for each application,you have to lift leafs where they touch each other,hit leaf bottoms at all angles,and just blast the bad areas real good.The other fungies keep it in check from getting uncontrolable,but does not kill it,im hopeing this works well.its about 120.00 for 2 1/2 gallons ,i found its best to split it with someone thats in the same boat.Best of luck to all.John

8/21/2003 9:10:59 AM

derry n.h u.s.a.

OOPS forgot to ask my question!
Has anyone else here tried this 3 step methid ,and what were your results if so?

8/21/2003 9:17:01 AM

Wood River, Nebraska

John, I've not done the three step but Zerotol has been working well for me so far. I use a backpack sprayer and one of the long arm pick up and reaching tools to pick up each leaf in order that I can spray the underside. Sure beats bending over. I'm anxious to hear how you do with the 3 step.
dave=stewee

8/21/2003 10:44:19 PM

derry n.h u.s.a.

Steve:
it seems to have worked,the powdery areas are drying up and turning brown,and no sign of new dew anywhere,Thank you lord. now if i can just get my pumpkin to start growing again!!

8/22/2003 4:03:37 PM

Montoursville, PA

John.........We are not sure why but a foliar feed called Vigor-Phos used in conjunction with kelp seems to prevent the growth of milldew in the first place. This product is from AGRO-K. Craig Lembkle one who is a member here is the company representative. Since begining to use it I have very little evidence of milldew. I have always felt kelp helps. In your recovery this may not be a bad consideration to add to your tricks. Craig's cjlemb@webtv.net 716-672-2367

8/22/2003 11:35:17 PM

Ctpumpkin@optonline.net

Dwaine,

It sounds like "potassium phosphyte". Can we lose the trade name & check for the actual ingredient name? Since Aliette lost it's patent there are no shortage of similar products on the street. But trade names confuse this issue.

Steve

8/23/2003 8:34:38 AM

Garden State Pumpkins

Got me thinking John...Came back to a bad case of PM after vacation...daconil wasn't having any effect so made a mix of ortho rose funginex and zerotol...it worked...maybe just the zerotol would have done it...got me worried while applying I noticed a reddish brown tint to the wet leaves and thought I had burned em but that wasn't the case...wouldn't have mattered since they were solid gray any way...haven't had to reapply since but will mix another batch this week.

8/23/2003 8:39:25 AM

Montoursville, PA

Steve, Agro-K has a tech bulleton that fully explains the value and well tested use of Vigor-Cal and Vigor-Cal-Phos
. It is not just the the 5% calcium, in the product. A host of healthy plant and ground ammendments or fertilization support is in the package.The total concept induces self defense mechanisms within the plants. It is known that various plant diseases, both fungal and bacterial, establish more easily in plants suffering from calcium deficiency or improper nutrient balance.

I understand your interest in specifics but when considering organic or healthy soil-plant builders the specifics are only a small part of the total supporting intent of the products. Just adding calcium in any form alone seldom improves the form or condition of calcium that the plant can use over a significant period of time. Only a healthy soil and soil plant relationship can right a wrong and maintain that ballance long term while even improving in the long term.

I personally do not need or even want to know specifically how they work. I am pleased to simply observe that they do work now and for years to come in most instances.

It would take up oodles of site space to lay this all out to many who may not be interested anyway. Anyone can go to the AGRO-K site and begin an investigation into the value of healthy soil healthy plant management. I have found them quite knowlegeable and helpfull in this area. Most of their products are helping nature build rather than treating specific ills. It just happens that on lettuce and now maybe pumpkins this specific compound product seems to enable the plant to ward off milldew...therefore reducing or in some cases eliminating the use of fungicides. They more than likely know it is the process in total not a single chemical, mineral or trace element.

8/23/2003 11:40:20 AM

Herndon, VA

John- Glad to hear that your PM is getting under control. Make sure you treat 'em with Daconil or some other fungicide that will stay on the leaves and help work as a preventative. ZeroTol is great for killing what's there, but will not protect against new spores that fly in overnight from your neighbors patch.

8/25/2003 10:25:42 AM

Ctpumpkin@optonline.net

Found it Dwaine. It ios Calcium Phosphite. Which is doing the same thing as Potassium Phosphite in the plant cells. Cool stuff. Phosphites are how Aliette got the job done. Now that the patent is expired there will be a lot more products like these. I suspect the kelp is keeping the Mildew down. Phophites are responsible for a whole raft of actions in the plant & may be helping.

The most noted effect is on Phtyophthora as we discussed over the winter.

Not organic though. But when marketed as a plant nutrient, phosphites are exempt from needing an EPA registration number. The seller/manufacturer has to be careful how they word the labeling though. The feds are just dying to generate some much needed revenue from fines if they discover someone marketing fertilizer ingredients as pest control products even though in this case, disease control is very real. You should see what our legal department did to the label of our "LESCO-PHYTE" before we could sell it. One might think it did nothing at all. But that's the price you pay to avoid litigation. Due to our size, the feds would view us as "easy picking low hanging fruit" if we claimed disease supression in writing. Smaller companies might think they're flying under the EPA's radar & try to get away with something. Lord help them if the "environment cops" get a hold of them. LOL

Steve

8/25/2003 11:16:21 AM

Ctpumpkin@optonline.net

I'll try to copy part of a research summary here so folks who like the tech stuff can see.

____Steve_________________________begin clip_______

PHOSPHOROUS PRODUCTS FOR TURF DISEASE CONTROL?
By Paul Vincelli
In response to questions received from golf course superintendents, I recently reviewed a substantial amount of literature regarding phosphorous acid (=phosphonate) materials and their disease control potential. Consider this as a "status report", since this topic is somewhat complex, interesting, and important. I plan to continue to investigate it further in the future, as I have more to learn about these materials.
Fosetyl Al (the active ingredient in Chipco Aliette) breaks down in the plant to phosphite (PO3-), which in some way is the active component. Phosphite is thought to stimulate plant defenses as well as to be directly toxic to fungi (in at least some circumstances). Now that the patent on fosetyl Al has expired, other manufacturers are interested in selling phosphonate products which are being represented as having the same disease control activity. This claim may or may not be true.
I reviewed six years of reports in Fungicide and Nematicide Tests, published by the American Phytopathological Society. This journal is not limited to turf disease control but includes studies on all crops. I was very surprised and disappointed to see how little research has been conducted on phosphonate products. For turf diseases, this is all I can say about the following products:
Fosphite (contains phosphorous acid) provided no control of anthracnose on annual bluegrass in the only report I could find on turfgrass disease control.

continued

8/25/2003 11:18:50 AM

Ctpumpkin@optonline.net

Prophyt (contains potassium phosphite, monobasic) was included in one test on turfgrass, for control of Pythium cottony blight. The product provided excellent preventive control for 20 days under high disease pressure.
Biophos L (a composted solid organic phosphate fertilizer): I could find only one report for turfgrass disease control with this product; at a high (12 fl oz/1000 sq ft) rate applied 2 wk before inoculation, it provided good control of Pythium cottony blight for 20 days.
I could find no published reports of turfgrass research on products such as Magellan, Phosguard, Nutrol, Ele-Max, Nutri-Grow, and Prudent Plus. There likely are other such products than those listed above; manufacturers are invited to contact me and provide technical information. A few products have been tested thoroughly on other crops, like Nutrol and Prophyt, but the above is still a pretty disappointing summary relative to turfgrass disease control. There are plenty of researchers in the turf disease control arena who are qualified to properly assess their potential. The products simply aren't being tested. Why not?
With the exception of the fungicide Magellan, none of the phosphonate products are labeled for turf disease control, to my knowledge. Several are sold as fertilizers only, and as such cannot be represented as disease control chemicals. To do so would be a violation of federal law. Furthermore, it appears in some instances that manufacturers may be avoiding taking the steps necessary to register their product as a phosphorous fertilizer with extremely low use rates rather than as a disease control chemical, perhaps hoping to avoid EPA regulations.

8/25/2003 11:19:00 AM

Ctpumpkin@optonline.net

rather than as a disease control chemical, perhaps hoping to avoid EPA regulations.
The chemistry of phosphorous in the soil and the plant is complex. For example, phosphite (H3PO3) applied to soil can be converted by microbes to phosphate (H3PO4) under oxidizing conditions and, in some soils, it can be converted back to phosphite and then to hypophosphite (H3PO2) under reducing conditions. Another example: some studies suggest that the ratio of phosphite to phosphate that the pathogen is exposed to determines how toxic the phosphite is to the fungus.
From a practical standpoint, the complexity of phosphorous chemistry reinforces the need for research on these products to find out how well and how consistently they control turf diseases. Maybe that is self-serving; I am an Extension Specialist. I feel a lot better about predicting how well a fungicide might work when there is a solid database of research to draw on. These transformations also suggest that phosphonate materials should be applied directly to plants and not watered into the soil, where they may undergo chemical changes.
Also, excess phosphite is phytotoxic, although reportedly at rates and formulations not reflective of the current generation of products. Nevertheless, this buttresses the need for research with the current phosphonate products. Be a skeptic: ask for the data.
_________end clip__________________________________

8/25/2003 11:20:16 AM

Ctpumpkin@optonline.net

Sorry about the length of all that.

Paul was studying turf grass only. Though Aliette was labeled (still is) for much more.

Calcium Phosphite would be the same as Potassium Phopsphite since the phosphites are converted in the plant cells to "phophorous acid". This is where the disease detroying exchange is taking place.

I have more stuff like this on other crop uses but none yet specifically for cucurbits.

I know most folks aren't interested in the technical aspect of this. But if so, send me an email & i'll forward what I can find. This stuff is very interesting to me & I enjoy exploring the options they afford us.

Steve

8/25/2003 11:24:24 AM

Montoursville, PA

I believe AGRO-K is selling the product into healthy soil healthy plant relationships. The result is little more than a peachy good side benefit. Nowhere is the word fungicide used yet the plants ability to ward of milldew in fact then reduces the need for fungicides or for less fungicide if one needs or feels he/she needs help.

From my non-technical viewpoint I am pleased that this and other healthy soil improvements or maintenance just happen.
The reverse consideration is just as important to me. If whatever I am doing nukes the good stuff that continually goes on in the magic of good soil I want to replace it with something that will build soil not nuke it.

We know in most instances all the elements of good soil are within most soils. All we need do is nourish it with our goodies to build back up to excellent. Once excellent is achieved maintenance becomes easy if we are careful about our additives.

8/25/2003 1:11:17 PM