What causes rot inside mango fruit?

[BestDay]

Hi guys, a friend of mine grows Spirit of 76 here in SoCal. The last couple of years the fruit appears to ripen on the tree fine. The problem is when you cut the fruit open it has rotten around the seed. Here are some pictures. Anyone know what causes this?

[gnappi]

Look here, there may be something 

https://en.wikipedia.org/wiki/List_of_mango_diseases

[BestDay]

I didn’t really see a clear answer on that link. Has anyone here experienced this?

Bill

[skhan]

This happen to a few of my fruit this year.
Not widespread enough for me to panic, I would also like to know what's going on.

From the little I could gather it seems related to Boron and Calcium. That's assuming the article i read was describing this same phenomenon

[brian]

Is it typical to apply boron to mangos?  The fertilizer I use has .01% boron, and I have a big bag of borax.  Sounds like you can go overboard and give boron toxicity but I can't find much in the way of guidelines for single trees, only acres

[Johnny Eat Fruit]

Hard to say. Continue to grow, and if this situation remains for the next two years, top work it to another variety better suited to your climate.

Johnny

[BestDay]

I guess I will recommend that he fertilizes his tree heavily this spring.  If he gets bad fruit again then I guess a top working will be needed.  Strange that this is happening and no one else has a reason.

Bill

[spaugh]

It looks like it was left on the tree too long but I don't really know.  Did they pick some a little earlier and still have the issue?

[cbss_daviefl]

Is there any seed at all? Is there still a husk with rot inside? I think it looks like an insect larvae attacked the seed embryo, and the rot is contamination from the larvae waste. There is a pest known as the mango seed weevil. They lay eggs on the surface of the fruits. The eggs hatch and the larvae consume the seed. The mango seed weevil is known to be in most mango growing areas, Hawaii and in the Caribbean, but not in Florida or California.  Maybe the weevils are already here or maybe these are being damaged by something similar.

[Galatians522]

If you want a true expert opinion, you should post on the mango diseases thread. My opinion is that your friend's tree has a very bad case of what is known as "jelley seed" which has been exacerbated by letting the fruit go all the way ripe on the tree. Not many people realize it, but mangoes actually ripen from the inside out. In a fruit suffering from jelley seed, the inside breaks down and gets over ripe (or rots in this case) before the outside of the fruit can get ripe. Some varieties suffer more than others. Just like blossom end rot in tomatoes it is the result of a calcium deficiency. You can ammend the soil with gypsum or dolomite, but that usually takes a long time to get absorbed by the tree and there might be an issue with your ph that won't allow the tree to get what it needs. Your best bet in my opinion  is to spray the whole tree with liquid calcium. Suposedly, the best time to spray the calcium is at fruit set, but a couple extra sprays probably wouldn't hurt. If that fixes the problem, then it was jelley seed. If it doesn't, then you have me stumped.

[BestDay]

I don’t know if the seed rotted from the inside out or the outside in. I will have to check next year. We will definitely spray the tree with calcium and try picking some fruits earlier next year and see if that makes a difference. I doubt if it is a weevil problem because his other three varieties aren’t affected.

Thanks for the great advice. We will try the recommendations and see what happens next year. If all else fails we can top work the tree.

Thanks
Bill

[cbss_daviefl]

My next guess is that it is spongy tissue, a different disorder from jelly seed.  Take a look at the article linked below, at the end of page 58 in the section titled "Nutritional factors related to physiological disorders in mango". It states that there are a few potential causes, low levels of calcium, low levels of magnesium, high levels of nitrogen relative to calcium.   If that is the case, stop all N fertilizer and treat with gypsum and epsom salt or Cal-Mag for next year's crop.

https://actascientific.com/ASNH/pdf/ASNH-06-0977.pdf