Questions tagged [diseases]

For questions related to plant diseases.

Plants can be infected by a number of diseases. These can be caused by micro-organisms (e.g. bacteria, fungi, viruses; and multi-cellular creatures such as nematodes).

Macroscopic creatures (e.g. mites and aphids) and water/nutrient problems (too little or too much) can also cause symptoms that can be confused with diseases.

Use this tag for all questions related to diseases - especially diagnosis, management, and cures. Please include pictures of the affected parts of the plants.

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What is causing diseased leaves on my French beans?

My French bean plants have diseased leaves as shown below: What can be causing this? The beans themselves are relatively plentiful. Location: India. Weather In May-June: Hot! > 95F days. The bottom side of the leaves have small white flying insects…
gatul
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What is causing the bark on my crabapple to crack and peel off?

I have a flowering crabapple in my yard whose bark has several large areas where it cracks and curls away from the wood underneath: Hover over any image for description / click for full size I don't know what variety it is (the previous owners…
Niall C.
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White crystal like spot on bottom side of chili leaves

I have a (thai) chili in my kitchen. It seems to be fine overall. One week ago I discovered some white spots on the bottom of the leaves (see image). Whatever it is it does not seem to be moving. It is also kind of hard to scrub off. I tried it…
チーズパン
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Chilli plant leaf curling

The leaf of my green chilli plant keep curling and wither away. I have tried treatment with neem oil pesticide /fungicide but it does not show any improvement The plant does not flower / produce chillis
Badri
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Beet plant - leaves turning yellow-brown

I have a beet plant that I grew from seeds. They started off great and healthy. In fact I plucked some leaves to use in a salad. After that some of the leaves are turning yellow and drying up. What could possibly be the reason?
JStorage
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What is this Apple disease?

Close up of lesions Close up stem side I've had this Apple tree for a couple of decades which I had always assumed it was wild since it had always produced sour small apples. For some years the skin has had these blemishes which extend a little…
Graham Chiu
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Why are the leaves on my houseplant turning yellow and getting black spots?

I have this shade plant in my home. The leaves are becoming dry, turning yellow and developing black dots on them. I don't know whats wrong with it. If it's a lack of food, I can give it compost, compost tea or kristalon. Can you please tell me…
user2120121
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Is this powdery mildew on my tomato?

Just noticed this on my store bought plant (not grown from seed). It's now fruiting, and I don't see any white spots on the leaves. Update: 25 Feb 2016 with close up of the stems and an more distant view of the plant health
Graham Chiu
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What is causing irregular brown sunken spots on my tomatoes?

I have been growing tomatoes in the same spot in my garden for years. This year most of my tomatoes seem to be affected by a disease which only affects the tomatoes. I prune, water & fertilize the plants regularly and they seem quite healthy…
laylarenee
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Is my mint plant dying or diseased?

About a week ago I decided to propagate a healthy stalk of mint that I had bought from the grocery store. The roots appear to be healthy and full, but two of the leaves appear to be abnormal. One of them is brown, and the other has a light…
AN1
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Why did my red bell pepper become tan colored?

I planted a red bell pepper seedling that I bought from a local nursery a couple weeks ago. It has been growing rapidly and upright. One of the egg-sized vegetables had suddenly developed a large tan splotch. Its leaves have suddenly curled up as…
JoJo
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What's causing these yellow veins on my Okra leaves?

My Okra leaves have turned as shown below Is this a deficiency or a disease? How can I remedy this? Location: India. Weather In May-June: Hot! > 95F days. Current: Overcast with light rains.
gatul
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Is something wrong with my zucchini plant?

I have three large zucchini plants in my garden, and all three have been producing nice fruits for a few weeks. The last couple days, one of them has started to turn yellow and sickly: I've never grown zucchini before, so I'm not sure if this is…
Flimzy
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Will peach leaf curl affect my fruit?

My peach trees have peach leaf curl. (Spring came too fast this year, I wasn't prepared, and I didn't get a chance to spray.) They're still young/small trees (10' tall), but they've got a bit of fruit on them. Will peach leaf curl affect the fruit?…
bstpierre
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What is happening to our potato plants? (going black, wilting)

We have a row of 3 different heirloom potato varieties, 50 originally, of which we've lost about 15 to a problem we'd like to identify. The following photos show the start of the issue, through to a completely wilted and near dead plant over the…
Lamar Latrell
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