How do I treat fungus on my squash plants?

Question

I have zucchini and yellow crookneck squash in my garden. So far I have managed to keep everything organic. However, I have recently discovered a black spore that is gathering on my flowers and stems. The fungus looks like dozens of black headed straight pins. There are also powdery spots on the leaves, and some leaves are yellowing, wilting, and dying. I also have three watermelon plants, as well as a cantelope. Are the fungi dangerous to the other "squash" type plants? Do I need to remove the summer squash plants, or can they be treated? I prefer to use an organic method, however, I am not adverse to trying whatever I have to in order to save my plants. Thanks fellow gardeners!

Answer 1

Wagner Bettiol, a scientist from Brazil, found that weekly sprays of milk controlled powdery mildew in zucchini just as effectively as synthetic fungicides such as fenarimol or benomyl. Not only was milk found to be effective at controlling the disease, it also acted as a foliar fertilizer, boosting the plant's immune system. In his experiments with zucchini plants, Bettiol found that a weekly spray of milk at a concentration of at least 10% (1 part milk to 9 parts water) significantly reduced the severity of powdery mildew infection on the plants by 90%.

Paul James, master gardener and host of Gardening by the Yard says he used a milk-and-water solution (1 cup of milk with 9 cups of water) to control powdery mildew on cucumbers twice a week and his powdery mildew problem disappear. Milk has a germicidal effect (it kills the fungal spores) & it also appears to stimulate plants in such a way that they become more resistant to the disease. "In recent university tests, the milk and water spray was found to be more effective than the two most popular synthetic fungicides on the market today".

Any kind of milk can be used, but Paul Crisp (University of Adelaide, Australia), recommends using dry-milk powder—15 grams for every liter of water. So far, he finds, this formulation appears to work on all surface mildews. It's best to use milk on sunny days because they need the sun's light to kick-start their mildicidal action.

David Bruer, formerly a professor of enology (winemaking), likes to alternate using different organic agents such as mik: (emulsified canola oil and bicarbonate once a week and then moving to a spray of whey and then seaweed extract the next cycle) because they appear to offer different modes of action in killing mildew. He is reluctant to use one organic fungicide exclusively saying: "That might make it easy for the mildew to develop resistance to control."*

Those black lessions sound like Choanephora Wet Rot. "The organism (Choanephora cucurbitarum) attacks summer squash as the blossoms wilt and quickly spreads down the fruit. A black mold, resembling tiny pinheads, appears on the necrotic area. Spores are spread by insects and splashing water. This disease is common under high moisture conditions". http://www.uga.edu/vegetable/squash.html
Chaonephora fruit rot is soilborne disease which rots the young fruit. "It can be controlled with a combination of treatments using foliar sprays of chlorothalonil, raised beds and open foliage varieties. This allows air movement to dry the soil and the foliage. Also, avoid planting squash on heavy, poorly- drained soils. Apply fungicides during wet periods". http://plantanswers.tamu.edu/vegetables/squash.html
After the crop has been harvested, all remaining debris should be removed and destroyed. A 3-year crop rotation should be implemented as the bacterium can persist in the soil for up to a year and a half. Handle fruit carefully to minimize injury prior to curing since infection also occurs post-harvest. (Another site recommended a 4 year crop rotation for fungal disease: anrcatalog.ucdavis.edu/pdf/7245.pdf)

Good luck! Hope this helps.

Answer 2

This Site Might Help You.

RE:
How do I treat fungus on my squash plants?
I have zucchini and yellow crookneck squash in my garden. So far I have managed to keep everything organic. However, I have recently discovered a black spore that is gathering on my flowers and stems. The fungus looks like dozens of black headed straight pins. There are also powdery spots on...

Answer 3

Mildew On Squash Plants

Answer 4

Take a leaf with the fungus into your local greenhouse. Be sure to put it in a zip lock bag.

I have found that the greenhouses that sell bedding plants are usually more knowledgeable than the folks at the bigger stores (walmart, lowes, home depot, etc).

They can identify it and you can also talk to them about organic vs chemical treatment, then decide what is right for you.

Answer 5

Pumpkins + goards typically have some fungus growing on them, I would physically wash the fruit to keep the fungus from building up. Perhaps some of the Soap incecticides that are pretty harmless would keep the fungas at bay.

good luck.

Answer 6

I have fungis on my cleminis plants what should I d/