Yellow sap in mangosteen

[ben mango]

Anyone had this problem with mangosteen? Not really sure how it works but the sap forms and then the inside of the fruit slowly starts to form this yellow growth. Ruins the fruit. I read that fertilizing with Calcium during the flowering stage can help but wanted to ask if anyone has personal experience correcting this problem.

[happyhana]

Talking about gamboge? Nasty yellow latex?

My understanding is that it is a physiological problem caused by damage to fruit while developing. So unpruned tree in a windy spot would cause this. A guess, no personal experience correcting.

I don’t have mature trees but a neighbor does. Almost all the fruit have gamboge and are inedible. Along with gumosis from standing water.

[happyhana]

Calcium makes sense; stronger cell walls to resist damage. Also Hawaiian soils are super deficient.

[Finca La Isla]

As the fruit develops, if there is a lack of calcium or too much water then the husk doesn’t keep up with the devopment of the pulp. The pulp gets squeezed and… Another problem besides the sap is that the pulp gets translucent and hard. Also a calcium deficiency.
Splitting jakfruits is basically the same issue.
Peter

[happyhana]

Thank you for the insights!

[Finca La Isla]

I was having this problem with a few of my mangosteen trees and others were consistently good. I obtained the information I shared from an Australian research paper. So I did leaf analysis of some trees that had problems and others that were always good. Sure enough, everything was pretty much identical except for calcium!
Peter

[Mike T]

Gamboge and translucent flesh disorders often go together and they are not by a disease/pathogen. Trees often have a few fruit with it. Some much more than others. Two things that may be partially relate seem to be behind it.How trees get watered and in places with a big wet season and dry season that is really dry it is more of a problem and also in poorly drained soils. Calcium is also involved and this can be due to balance with K and even Mg and soil acidity can influence Ca availability.

[ben mango]

Peter, have you tried fertilizing with calcium to correct the problem? I remember you mentioned you had this problem with a couple trees. The lady I’m working for has it on all her trees. The first flush of fruits were mostly good but by the 2nd flush they are all ruined. Trying to correct this issue for her next season

[Finca La Isla]

Hi Ben
So I would apply calcium carbonate or dolomite in a wide band on both sides of the drip line at least twice a year. 500 grams per square meter. When fruit sets apply calcium with boron foliar spray every two weeks.
It would be nice to have a soil test to work with and to be doing leaf analysis to see if the trees are really absorbing the calcium and then see how it effects fruit quality.
Suerte!
Peter

[happyhana]

Aloha Ben, you in Hawaii?

Gypsum is recommended form of calcium here. Dolomite raises ph and adds magnesium which we generally have enough of. Gypsum also has sulphur and will not increase ph. What Peter said, best to have soil analysis.

[ben mango]

good idea Peter and thanks for that added input, happy Hana, and yes, Kona side. With what you said earlier the tree really need a good pruning too so maybe that will help them. I’m planning on having a soil test done sometime soon and will look into getting a leaf analysis done as well. It’s a shame when there would be a decent crop coming from these trees but right now it’s all going bad