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Phytochrome-mediated Carotenoids Biosynthesis in Ripening Tomatoes
1Department of Food Science, Clemson University, Clemson, South Carolina 29631.
Plant Physiology
|September 1, 1975
Summary
Red light promotes carotenoid biosynthesis in tomatoes, while far-red light inhibits it, indicating a light-mediated process. This suggests distinct pathways for carotenoid production influenced by specific light wavelengths.
Area of Science:
- Plant biology
- Photomorphogenesis
- Biochemistry
Background:
- Carotenoids are vital pigments in tomato fruit development.
- Light quality is known to influence plant growth and development.
Purpose of the Study:
- To investigate the effect of red and far-red light on carotenoid biosynthesis during tomato ripening.
- To elucidate the role of light signaling pathways in regulating carotenoid production.
Main Methods:
- Ripening tomatoes were exposed to different light conditions: red light, far-red light, and darkness.
- Carotenoid content was quantified using spectrophotometric methods.
- The effect of sequential light treatments (far-red followed by red) was assessed.
Main Results:
- Red light significantly induced carotenoid biosynthesis compared to dark controls.
- Far-red light inhibited carotenoid biosynthesis.
- Red light reversed the inhibitory effect of far-red light, suggesting phytochrome involvement.
- Analysis of individual carotenoids supported the existence of two separate biosynthetic pathways.
Conclusions:
- Light quality, specifically red and far-red wavelengths, plays a crucial role in regulating carotenoid biosynthesis in ripening tomatoes.
- The observed responses suggest a phytochrome-mediated signaling pathway controlling these processes.
- Evidence supports the hypothesis of distinct carotenoid biosynthetic pathways in tomatoes, differentially regulated by light.
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