Influence of climatic factors on the carotenoid concentration of tomato fruits and their protective mechanism when exposed to moderate UV-B before harvest
C.P. Pérez, C. Ulrichs, S. Huyskens-Keil
Acta Horticulturae 1016: 69-75.
2014
บทคัดย่อ
With the purpose of increasing the concentration of bioactive compounds and evaluating the influence of climatic factors on the tomato, cultivar ‘Liberto’, fruits were exposed to physical stress in a glasshouse in Berlin before harvesting through the application of moderate doses of UV-B radiation in November, 2007 and in May, 2008. The objective was to investigate whether its use had an eliciting effect on the secondary metabolism that resulted in a change in the concentration of bioactive compounds. Two UV-B radiation doses were used: a) range between 0.075 and 0.105 Wh m-2 and b) 0.15 Wh m-2. The mean photosynthetic photon flux density (PPDF) was 18.8 mol m-2 d-1 in May and 5.9 mol m-2 d-1 in November. After 22 hours of adaptation time, the ripe tomato fruits were harvested to determine the lycopene and β-carotene contents. The results showed that the exposure of ripe fruits to UV-B caused β-carotene accumulation in the November-treatment. Temperature and PPDF showed a strong influence on β-carotene and lycopene accumulation, as well as on the dry matter content. The May- and November-treatments differed significantly with respect to carotenoid content between the non-treated fruits and those treated with UV-B radiation.