Kostas

Hello

One of my AAA East African Highland bananas is yellowing/blackening the older leafs in a strange pattern:






What causes this and what can I do to prevent it?

Thank you very much in advance!

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kubali

looks like you got some Black sigatoka

Kostas

This is Black Sigatoka? Didn't know that! It has been happening every year the last years every time the weather cools down some. I have had bananas get it real bad and have few leafs remaining till the end of the wet season. But only very very few cultivars are affected. Unfortunately the AAAs seem to be at least moderately affected. Have you found any cultural practice particularly helpful at keeping the bananas healthier? Winter is coming so I want the important ones such as this EAH AAA be as strong and healthy as possible...but without spraying pesticides.

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Kostas

I looked at Black Sigatoka pictures again and it doesn't really look like them. Neither the pattern nor the damage. The leafs do not dry like Sigatoka affected ones,nor develop clean steaks like i see. They all end up the way you see and linger in a yellowed state with black and water soaked brown markings. No idea what causes it. Its not Cordana either,i do have Cordana and get it some years but as far as i am aware and have taken all measures against introducing,i don't have black sigatoka. I do have various leaf fungi and get quite some damage from them on various plants in wet years but not black sigatoka in the form i see it in pictures. Is it black sigatoka or something else maybe?

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kubali

what it looks like to me and happens when real wet, but I am no expert on banana disease you might ask Nicolas naranja he is a member here that grows bananas down in south fla and I'm sure he would know what it is.......Fusarium wilt of banana or maybe xanthomonas wilt like I said no expert on banana disease just trying to help you.

Kostas

Thank you very much for your reply Kub Just sharing the info i have so that we can make an educated diagnosis. The black sigatoka was a good guess,but i haven't found any pictures of it depicting this kind of damage. It shows differently as far as i can find. I am no expert either but have read the major banana diseases thoroughly so that i know what to watch out for and to follow a protocol successful at preventing their introduction here,since they do not exist in Greece.

It is still hot here and does have rained a few times but it doesn't have its leafs wet regularly, though the weather does is overcast and humid. It gets sun as well though,so damaged tissues that cannot sustain themselves would be dry fast.

Its definitely not fusarium or xanthomonas i think,most all bananas of mine did that when really young and most thrive to this day,they would be long dead otherwise and they would have had the rest infected as well

But the cause and way to keep it from happening still escapes me...So all help is needed in making an ID of this. Anyone else has had that happening?

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Nicolas Naranja

Is fertilizer or salt burn a possibility? The other option I might suggest is sulfur deficiency

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Kostas

Thank you very much Nicolas!
No,neither fertiliser nor salt burn should be a possibility as i have a very long time to fertilize and we had heavy rains earlier this month that would leach out any possible salt accumulation from the dry season.

So, sulfur deficiency causes such symptoms? As you can see, the severity on each leaf is a little random. Would fertilising with an organic fruit tree fert stop this from continuing if its sulfur deficiency?
Any,even remote,chance of it being sigatoka?

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''To try,is to risk failure......To not try,is to guarantee it''

Nicolas Naranja

Does not look like sigatoka at all.

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Some people go bananas, I went plantains.

Kostas

Thanks for confirming that Nicolas! Great to be sure!

__________________
''To try,is to risk failure......To not try,is to guarantee it''

Nicolas Naranja

Give it a shot of epsom salt, you aren't going to revive the dead leaves but you might prevent further damage

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Some people go bananas, I went plantains.

Kostas

Thank you,i will! Lets see what happens

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siege2050

A few of mine started looking like this since the weather has cooled off, and days length is shorter too. Its not fertilizer burn here because I was giving them much more a month ago, and slowed down because its closer to fall, You are in a higher growing zone so not sure, but I am thinking it is seasonal, maybe due to shorter day length or temperature.

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Kostas

Thank you very much for your reply!

They do seem to do that every fall or with cool evening temperatures and I had thought it was temperature related or the leafs staying too wet too often, but right now it makes no sense to be caused by the temperatures alone especially being a tropical highland banana,thus the temperatures it's seeing right now here would be the usual temperatures it would see at its place of origin(18C min and 28C max). It's not too cool yet. And the other EAH AAA are not getting such damage yet. It's puzzling...

Let's see if light fert and micronutrients fix it, it does seem to be missing fert,more than one element...

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cincinnana

I agree with Siege.
And if you notice it is generally the oldest leaves on the plant that start decaying first as the summer season changes to fall.
Mine do basically the same thing every fall.
Just my guess though and my plants seem to be disease free.


.I trim leaves like this once a week or so.

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Kostas

Thank you very much for your reply!

Mine got it worst on 2 random leafs,not the oldest ones only. But maybe the change to cooler(though still warm) weather contributes to that as well.

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