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 the problem/disease that causes bobbly peach tree leaves?

What is the likely cause of the bobbly forms on the leaves of a peach tree? Does it matter or is it just some natural anomaly that doesn't affect the tree's health? If is it a concern how can it be treated? The tree in question is about 1m (3 ft)…
Lisa
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What causes cucumber leaves to turn yellow, brown, wilt, die, and the plants to stop producing?

Every year it seems my cukes will go gang busters then suddenly the leaves turn yellow (starting with yellow spots), then turn brown, wilt and slowly die off. This all happens from the root crown and works its way out. I have pictures of early…
Bill
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How dangerous are the roots of brassicas (cabbage, broccoli etc)?

I've read that putting the roots of brassicas in the compost is a bad idea because of the risk of disease. I've also read that you shouldn't even plant them in the same spot for three years! What can you do to mitigate the danger and how dangerous…
Peter Turner
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What disease is causing raised blisters on the leaves of my plant?

Plant :Alstonia Appearance:Blisters (gall) on both sides,cutting galls leaves white fluid. After some time holes apppears in the blisters.so it seems some insect laid eggs. What kind of disease is this? It seems to be some kind of blisters on the…
Atul
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Why does my blueberry bush have brown/scorched leaves?

I recently purchased a dwarf Northsky blueberry bush from a mail order company. When I recieved it, roughly 15-20% of its leaves had the appearance of being burned or scorched; the bad leaves were about 50% brown and curled, like they were burned or…
Ashley Grenon
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How do I treat rhubarb rust?

I have a small rhubarb plant and one of the stems has gotten some rust on it. What should I do? (there are only 3 small stems on the plant)
Dale
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Why are the leaves of my pea plant (little marvel) drying up and turning brown?

The pea plant (Pisum sativum) was grown in an ebb & flow hydroponics system until it failed; now it's in a deep water culture unit. I noticed that the leaves were turning brown/grey. I thought this may be a disease so I sprayed Daconcil when needed,…
linuxrules94
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How do you manage dying leaves on young plants?

If a leaf on a plant is shriveling or yellowing, should you cut it off or leave it there? If you do the former, should you only snip off the damaged parts or should you cut off the entire leaf? My question is pertinent to young plants that may have…
JoJo
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What is happening to the leaves of my avocado?

I have an avocado plant in my outdoors balcony. It's been growing nicely, but there are small brown dots/holes in the leaves for some time now. I don't see anything in the underside of the leaves, and up until now new, healthy looking leaves have…
Eyal
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Grapevine leaking water and white mucus

Problem While I was recently helping my mother prepare her garden for the spring, I discovered that the leak on her porch was not actually coming from the overhang above the door, but rather from a branch of her grapevine. Observations Examining…
Synetech
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Cucumber disease/ pest identification

Can anyone tell me what is happening with this cucumber plant?
Machak
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Why is my pear tree dying around the blossoms?

Shortly after the blossoms fell on my pear, areas around the blossoms started to turn black and die. This is spreading. Although the dead areas tend to be on the end of the branches, there are exceptions where a branch may have 2 or 3 dead zones…
winwaed
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What's wrong with this fig?

I have a fig tree in a pot in my balcony. Recently it has lost a couple of leaves and they all display the same features: yellowish color on the front side of the leaf, and tiny small white dots on the reverse. Some of the leafs in the tree are…
ariera
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Is there any cure or treatment for a queen palm tree diagnosed with fusarium decline?

A "certified arborist" looked at the tree (>20ft high) and determined that this was the cause. Some of the fronds in the tree seem frozen in place, while most have actually drooped down completely (but not fallen). The arborist said that it was a…
Phillip
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Why do my tomato leaves look powdery?

I have a threesome of tomato plants planted in on my porch. All three have some leaves that seem to be a bit white and powdery. One of the leaves has even started to turn a bit brown. I don't think this is blight, I'm pretty sure I know what that…
wax eagle
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