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Author Topic: Meyer lemon leaves with odd symptoms - advice needed  (Read 258 times)

matt_citrus

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Meyer lemon leaves with odd symptoms - advice needed
« on: August 25, 2017, 01:27:31 PM »
To be honest, I tried another forum a month or so ago but am looking for more opinions. There was a long-ago post where another user (in Florida) had the same issue but never indicated if it was resolved (not sure if we can link there, but if you web search for "Problem With Meyer Lemon Leaves" and "charles27gardener" his post will show up).

My improved Meyer lemon (on a standard non-dwarfing rootstock) has been growing like gangbusters since planting a year ago. Recently, the underside of many of the leaves have started to become covered with rough brown spots. A number of the leaves fall off.

This is the only tree experiencing the issue of five trees that are about the same size and on the same watering schedule (two blood orange, one minneola tangelo, one page mandarin, and this meyer lemon).

The suggestion was fungal and that fungicide could control - I've begun that regimen but it continues to get worse (more leaves falling off, at the same time the tree is flushing with newer growth). Could it be mites? Edema? Fungal but takes longer to control? Other ideas?

I'm in the coastal Los Angeles area. Theoretically greasy spot is rare here?

Top of leaves, backlit (no noticeable issues with tops of leaves, but you can see where whatever is happening is affecting the tissue to make it lighter yellow) (Click for full-size)


Underside of leaves, note (necrotic?) brown spots (Click for full-size)


Fallen leaf top and bottom (click for full-size)


The tree itself, in lighting that doesn't reveal the issue, except for the defoliation near the top:

Susanne42

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Re: Meyer lemon leaves with odd symptoms - advice needed
« Reply #1 on: August 25, 2017, 01:44:40 PM »
Maybe a combination of Parasites (mites,thrips?) and fungus?
What did you use to treat the tree?
I would think that whatever you used willl not cure the leaves but prevent from spreading to the new flush. Seems that looks healthy and green??
« Last Edit: August 25, 2017, 01:48:08 PM by Susanne42 »

matt_citrus

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Re: Meyer lemon leaves with odd symptoms - advice needed
« Reply #2 on: August 26, 2017, 09:27:54 PM »
Monterey Liqui-Cop (Copper diammonia diacetate complex) and more regular treatment of horticultural oil (I tend to use Southern AG's Parafine). New flushes seem healthy but the spread continues. Have not seen any webbing but mite damage would be consistent with the rapidity...

How does everyone avoid / suppress mites on their trees?

Mark in Texas

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Re: Meyer lemon leaves with odd symptoms - advice needed
« Reply #3 on: August 27, 2017, 09:10:47 AM »
Mites can easily be blasted off with water or use a dormant oil.  Forbid 4F is THE silver bullet but is not listed for citrus.

Keyplex 350 DP is the silver bullet for chlorosis but that almost looks like some kind of blight or virus.  Recommend you take a leaf to your local ag extension specialist or send a sample into a lab for analysis.

 

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