Author Topic: LZ spot on mature fruit  (Read 877 times)

palmcity

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LZ spot on mature fruit
« on: July 27, 2019, 07:14:21 PM »
Previous mention of LZ dark spotting of mature fruit on posts by Simon & JF: 
Reply post 183:   http://tropicalfruitforum.com/index.php?PHPSESSID=8d7309df3a74a261b6df161b372d9c7e&topic=28697.msg336940

And Reply post 184 of same thread, "I’m assuming that black spot is some surface fungus caused by moisture retention from the styrofoam Asian Pear wraps I use to protect my fruit. Wrapping the fruit with these types of wrappers seems to keep birds and rodents away but they hold moisture where it contacts the fruit. "




Many but not all of my LZ have had this spotting. IMO it is not a fungus. I applied today household bleach 6% to two LZ and there was no change in the coloration of the skin after 4 hours except where there was other fungus from clinging to insect secretions etc.

When my LZ are first picked at a yellow color the spots are very light green. Over the next 5 days the fruit changes color to orange and the very green spots now become very dark green like yours and appear almost black.

I am guessing these spots to be chlorophyll movement.

Plants often exhibit chlorophyll movement when mineral deficiency occurs as with chlorosis in leaves. It is now deficient of additional minerals when pulled from the tree so I guess movement of chlorophyll is possible and it does seem to broaden and become darker green to blackish with time. While reading online today I also found additional talk of chlorophyll movement in extreme heat and perhaps this is in play with our LZ also as temperatures before and after picking the fruit may help create the problem. Still unknown as far as I know and just some guessing again, but I do not think it to be due to fungus issues. I also agree that it causes no internal problems with the taste as far as I can tell. 

I ate one of these two today but should have waited at least 1 or 2 more days to turn darker orange as it was only 4 days sitting inside so far.

before adding bleach

bleach is the clear liquid on the fruit now

after beach has dried = no effect.

after bleach, cut piece inverted.

These are not yet as dark as Simons so I will try not to eat one for a few more days to add picture when it darkens more... If I can wait & as long as the other animals in the house do not eat it first (relatives visiting)...
« Last Edit: July 27, 2019, 07:16:25 PM by palmcity »

simon_grow

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Re: LZ spot on mature fruit
« Reply #1 on: July 27, 2019, 08:08:22 PM »
LZ naturally has a birthmark spot on it but your spot seems to be much larger than I normally see on LZ.

Simon

palmcity

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Re: LZ spot on mature fruit
« Reply #2 on: July 27, 2019, 09:07:59 PM »
LZ naturally has a birthmark spot on it but your spot seems to be much larger than I normally see on LZ.

Simon

My spots have been enlarging and darkening since picked.

Also note that the spot in your previous thread post was very small when fruit was picked greenish. It also grew 4 to 6 times in size or more during the ripening stage after being picked. I am guessing chlorophyll migration expansion. Look at borders in your picture of the spot.  Reply post 183:   http://tropicalfruitforum.com/index.php?PHPSESSID=8d7309df3a74a261b6df161b372d9c7e&topic=28697.msg336940

simon_grow

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Re: LZ spot on mature fruit
« Reply #3 on: July 27, 2019, 09:13:46 PM »
Great observation, I hadn’t noticed that before. I knew about LZ having a birthmark but I never paid attention to it getting larger, even after harvesting from the tree.

Simon