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Citrus => Citrus General Discussion => Topic started by: Piss P on September 22, 2021, 11:51:38 AM

Title: Yuzu Leaf Diagnosis - Hypopigmentation?
Post by: Piss P on September 22, 2021, 11:51:38 AM
Hey All,

I have a young Yuzu that I recently brought indoors for the winter and I am noticing some yellow spots developing on the leaves (pics below). My thoughts are either a reaction to being moved indoors under new light or a nutrient deficiency. Let me know if y'all want more pics or info.

Any and all advice/thoughts about what could be going on are welcomed!

Thanks
pp
(https://i.postimg.cc/K3yPVBtM/IMG-6418.jpg) (https://postimg.cc/K3yPVBtM)

(https://i.postimg.cc/t7XthtRK/IMG-6414.jpg) (https://postimg.cc/t7XthtRK)
Title: Re: Yuzu Leaf Diagnosis - Hypopigmentation?
Post by: tedburn on September 22, 2021, 06:04:48 PM
perhaps this link can help you
https://www.yara.fr/fertilisation/solutions-pour-cultures/agrumes/carences-agrumes/ (https://www.yara.fr/fertilisation/solutions-pour-cultures/agrumes/carences-agrumes/) even if it is in french
regards Frank
Title: Re: Yuzu Leaf Diagnosis - Hypopigmentation?
Post by: Piss P on September 23, 2021, 09:01:04 AM
Danke Frank!

For posterity I will be following up on this.

Looking further, I now believe it is mesophyll collapse that came about via water stress (I err on underwatering vs overwatering) or root damage/stress from transplantation. My initial inkling came from this http://ipm.ucanr.edu/PMG/W/A-CI-WSNE-FO.001.html (http://ipm.ucanr.edu/PMG/W/A-CI-WSNE-FO.001.html) and I became confident in this diagnosis after reading https://www.ncbi.nlm.nih.gov/pmc/articles/PMC438118/pdf/plntphys00285-0149.pdf. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC438118/pdf/plntphys00285-0149.pdf.)

Mg deficiency is my second guess so I am going to throw some MgSO4 at the base for good measure. 

pp
Title: Re: Yuzu Leaf Diagnosis - Hypopigmentation?
Post by: Millet on September 23, 2021, 10:26:37 AM
Piss P your tree's leaves certainly are not showing a Magnesium deficiency.  The symptoms for a magnesium deficiency is a darker green delta shape at the bottom of the leaf structure on an other wise green leaf.
Title: Re: Yuzu Leaf Diagnosis - Hypopigmentation?
Post by: Piss P on September 23, 2021, 10:47:53 AM
Millet - good to know. Appreciate it! Any thoughts on my diagnosis?
Title: Re: Yuzu Leaf Diagnosis - Hypopigmentation?
Post by: incubator01 on October 02, 2021, 06:15:31 AM
the back of that leaf certainly has a lot of dark dots, if it's not dirt, it could be bugs? (mites, aphids?)
Try spraying the back of those leaves with water so they're clean and see if it gets worse or the spots come back. If so you may need some neem oil based product.

Indoors many plants get insects because it's a lot warmer there, I had armored scale in january once on a kaffir lime, it was terrible :( there was a whole colony on every branch.
Title: Re: Yuzu Leaf Diagnosis - Hypopigmentation?
Post by: flos on November 11, 2021, 07:11:43 AM
Hello together,
i got the same spots on my clemyuz22 and where unable to find a real diagnosis.
I found some article in the citrusindustry-newsletter. Herbizid-damage looks a bit similar to our "disease".

Could this be possible?

https://citrusindustry.net/2021/11/08/impacts-of-herbicides-on-young-citrus-trees/?fbclid=IwAR3gEVwe63B7E644v91SwgR8XWgx97mCKAVEUZYTfVK-zo_FeId68yy0Ap0 (https://citrusindustry.net/2021/11/08/impacts-of-herbicides-on-young-citrus-trees/?fbclid=IwAR3gEVwe63B7E644v91SwgR8XWgx97mCKAVEUZYTfVK-zo_FeId68yy0Ap0)


Title: Re: Yuzu Leaf Diagnosis - Hypopigmentation?
Post by: brian on November 11, 2021, 10:19:27 AM
two of my in-ground, in-greenhouse trees have this same issue.  One is a Xie Shan satsuma, the other is a Valentine Pummelo.  the Valentine Pummelo has had a recurring red spider mite infestation, but the Xie Shan despite being right next to it, hasn't had an obvious mite problem.  I spray both when treating, though.  These two trees are located right next to each other in an area of my greenhouse that sometimes has standing water when it rains heavily outside, because inside the greenhouse it is actually below grade relative to the outside.  I suspect that flooding is the root cause of this for me, and the spider mites are exacerbating it.