COMPOSITION OF CAROTENOIDS IN TOMATO FRUITS AS AFFECTED BY MODERATE UV-B RADIATION BEFORE HARVEST

Tomato fruits are a rich source of bioactive compounds, such as carotenoids.
In order to increase health-promoting compounds in fruits, we studied whether the application of moderate UV-B radiation has an elicitor effect on secondary plant metabolism, and thus, subsequently change bioactive compound concentrations and composition in tomato fruits without morphological defects.
Therefore, tomato fruits cv.
Liberto were subjected to UV-B radiation before harvest with an UV-B dosage of 0.075 and 0.15 Wh m^-2. After different adaptation times of 22 and 44 h the concentrations of carotenoids in ripe tomato fruits were determined.
The present results showed that UV-B exposure before harvest caused an accumulation of lycopene and -carotene content.
The highest increase in lycopene and -carotene was induced by an UV-B dosage of 0.075 Wh m^-2 after 22 h of adaptation time.
Thus, the synthesis of carotenoids was promoted by moderate UV-B radiation before harvest.
However, it was demonstrated that time and duration of the UV-B exposure led to a plant compound-specific response, which has to be investigated in further experiments.

International Symposium on Tomato in the Tropics

C.P. Pérez, C. Ulrichs, S. Huyskens-Keil, M. Schreiner, A. Krumbein, D. Schwarz, H.-P. Kläring

UV-elicitor, bioactive compounds, lycopene, Β-carotene, antioxidant, ripening

https://doi.org/10.17660/ActaHortic.2009.821.24