So, inside this orange, there is this "alien" thing. Before I want to say that this is GMO, I need a reasonable explanation about this. What is this thing?

(Warning: potentially phobia-inducing image. Images hidden behind the spoiler block. Click to reveal)

  • 10
    What a great 'alien'! Not something that would distinguish GMO from a natural orange. GMO attempts to perfect nature, make it better. This will be interesting to discuss!
    – stormy
    Apr 8, 2018 at 18:34
  • 2
    You need to give us more information: (A) how old was the orange? (B) was the orange seedless? (C) a photograph of the outer rind — i.e. the underside in that photograph. (D) how, exactly, did you prepare the orange? (E) what does the green thing feel like? (F) don't sniff it too deeply, but please describe the odor. I'd wish to upvote, but we need more info. Apr 9, 2018 at 1:47
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    Note: oranges are not natural, but gone long selection (and crossing) by humans. So it is genetically (and physiologically) not stable, especially on old plants. As far I know, there is no GMO orange (but just non-GMO marketing [which means "terrorism" to consumer]). It is also difficult to do GMO on long living individual (as I wrote old plants "changes", before to commercial use orange GMO, one should be sure that after 20 years one can still harvest GMO oranges. So longer testing, more costs. [coffee could be the exception, because of coffee crisis] Apr 9, 2018 at 5:57
  • 3
    Ironically, from the answers posted so far it seems like the answer is closer to "Because it's not GMO".
    – pipe
    Apr 9, 2018 at 11:13
  • 2
    Please mark NSFW. Apr 9, 2018 at 11:30

2 Answers 2


Preface: This answer is based solely on the search result. I'm not a gardener and I don't have any gardening knowledge to sufficiently answer this with full certainty.

Looking at the picture, it seems the most prevalent thing is the blackening of the core. Researching that gave results to a similar symptom from Alternaria/Black rot. This is caused by Alternaria spp. (e.g. Alternaria citri, Alternaria alternata), a fungal plant pathogen.

Some research papers on this:

  • 1
    black core rot caused by Alternaria fungus looks like the cause. Apr 9, 2018 at 5:30

Definitely looks like something from a sci fi/horror movie! Black areas within oranges are usually caused by a fungal pathogen - it enters most often at the 'navel' end of the orange and then spreads inside the fruit in varying degrees. It most often spreads up the central area, but can appear as small black areas in some of the cells of the orange. However,there is usually a small black or brown spot on the skin outside too, and internally, the spread is definitely sooty black, not greenish grey.

I've never seen a structure like that in association with a fungal infection; it's not impossible, but it's much more likely there might be another explanation - some kind of infection (fungal or otherwise) or randomly occurring DNA disruption has caused a mutation in the cells of the orange, creating this growth, rather than its just being the usual black rot.

It's unlikely to be related to GMO - these things do occur quite naturally, including in human beings, unfortunately.

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