black sigatoka?
 

Hello everyone,

I have a slight problem. I am leaning towards a fungus. I can't quite identify the disease. Black sigatoka looks more spotty and generally starts from the centre of the leaf. This is strange, newest leaf seams to show more symptoms where as the other leaves have like rusty looking streaks.

I fertilise quite a bit, once a week at least, could this be affecting it?

Take a look at the photo's.

Re: black sigatoka?
 

Add water.

Re: black sigatoka?
 

I water it at least 3 times per week especially now that it is summer in Australia. What do you guys think it is?

Cheers

Re: black sigatoka?
 

G'Day Amp285,

You may want to rethink your assumption that Black leaf Streak (Sigatoka) begins in the leaf center or toward it. Wherever the water stays on the leaf long enough to support the "fungal" growth is where it starts.

Good growing! :2239:

Re: black sigatoka?
 

Those photos do not depict black sigatoka, in my opinion.

Re: black sigatoka?
 

If I understand correctly there are several banana diseases in the bananas native range that have not yet made it to Florida. I have only seen some of them in pictures and the International Banana Research site.

Scott, what disease do you think this is? :2239:

Re: black sigatoka?
 

Caloosamusa: I think there is nutritional deficiency plus some physical injury resulting from lack of water or too high or too low temperature, perhaps. I do not suspect a pathogen, but rather a physiological cause.

Re: black sigatoka?
 

Some trace metals can be toxic, I have seen deficiencies, color changes in the leaves usually yellow or lighter shades of green become apparent in different patterns, depending on the elemental deficiency. Leaf necrosis occurs usually with too much of a trace metal, especially when waste sludges are used, or near a septic tank.

Magnesium might be the problem. There can be too much of a good thing.

Soil and tissue samples could confirm.

This is just a possibility, a WAG (:ha:) more than a hypothesis. :2239:

Re: black sigatoka?
 

it looks like it has some fertilizer burn to me. Also depending on what kind of soil you have you may be still underwatering. Or if it's heavy sticky clay, you may be overwatering. What kind of soil is it in --and what kind of fertilizers are you using?Also what exactly is the weather like there, typically sunny and hot in the 90's or cloudy and 60's. What is the typical night time lows in the last week or so? Is your banana potted or in the ground.

Re: black sigatoka?
 

Hi people,

The plant is in a pot. I decided to take it out and found the following. The roots were black and very soft which means they were rotted. I think that i over watered them. The temperature here is about 30 degrees celcius. The roots at the bottom of the pot were white and healthy. I have re-potted it, hopefully it regenerates. Do they generally regenerate or once the root system has been rotted its time to throw out?

Cheers