Change PQ SPAD

Project Guidance

Hi. Measured adaptation of leaf to dark, after turn off light.

n/a - control plant on light 0,2 - 20 minutes after turn off light 0,5 - 50 minutes after turn off light 1.5 - 90 minutes after turn off light

Changing many parameters. This is normal. But why change PQ SPAD???

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    Jul 2016

  • last reply

    Aug 2016

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Greg Austic

Aug 2016

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Just making sure I'm seeing what you're seeing - is it this time series graph? I do see a rise in SPAD from the first time to the 2nd, after which it stays constant. What was the light intensity prior to the data being collected? When the data was collected it was quite low (50 uE). It's possible if the intensity was really high before, then there could be chloroplast movement (?). I know that apparent chlorophyll content can change due to chloroplast movements over minutes/hours, and if it were high light before the experiment started, the plant could be getting greener because of chloroplast movement (?).

Maybe yes, this is chloroplast movements. I saw this only after turn off light for plant that growing on light. In plant that growing on impulse regime of lighting after turn on continuous light was not observed this effects.