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Gourd UV fluorescence

Fluorescence
23 replies to this topic

#21 colinbm

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Posted 03 December 2020 - 11:42

View Postbobfriedman, on 03 December 2020 - 11:30, said:

no idea.

Why does there seem to be a cut-off in the area of fluorescence & non ?

#22 Andrea B.

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Posted 03 December 2020 - 17:55

I would suggest that the cyan might be due to a mould or fungus on the surface (and maybe not very visible to the eye without fluorescence).

That's what I'm thinking. :smile:



Why does there seem to be a cut-off in the area of fluorescence & non ?

Not all pigments fluoresce similarly (or at all) under 365 nm UV stimulation. The orange carotenoids, for example. And if the cyan fluor is due to organic deterioration, then the undeteriorated gourds would not have that.
Andrea G. Blum
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#23 colinbm

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Posted 04 December 2020 - 02:14

View PostAndrea B., on 03 December 2020 - 17:55, said:

I would suggest that the cyan might be due to a mould or fungus on the surface (and maybe not very visible to the eye without fluorescence).

That's what I'm thinking. :smile:



Why does there seem to be a cut-off in the area of fluorescence & non ?

Not all pigments fluoresce similarly (or at all) under 365 nm UV stimulation. The orange carotenoids, for example. And if the cyan fluor is due to organic deterioration, then the undeteriorated gourds would not have that.

The individual fruit seem to be bifurcated in where they fluoresce & don't fluoresce, ie the top half does not fluoresce & the bottom half does fluoresce ?

#24 Andy Perrin

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Posted 04 December 2020 - 09:32

Yeah, I noticed that with mine also. The fungus or whatever it is did not grow evenly on all parts of the gourd. It seemed to “like” some areas more than others.