Volatile organic compounds characterized from grapevine (Vitis vinifera L.) berries increase at pre-harvest and in response to UV-B radiation.

GIL M, BOTTINI R, BERLI F, SILVA MF, PONTIN MA, PICCOLI PN

PHYTOCHEMISTRY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2014

0031-9422

Ultraviolet-B solar radiation (UV-B) is an environmental signal with biological effects in different plant tissues. Recent investigations have assigned a protective role of volatile organic compounds (VOCs) in plant tissues submitted to biotic and abiotic stresses. This study investigated VOCs in berries at three developmental stages, veraison, pre-harvest and harvest, of Vitis vinifera L. cv. Malbec plants exposed (or not) to ?field-like? doses of UV-B both, in in vitro and field experiments. By Head Space-Solid Phase Micro Extraction-Gas Chromatography-Electron Impact Mass Spectrometry (HS-SPME-GC-EIMS) analysis, 10 VOCs were identified at all developmental stages of berries: 4 monoterpenes, three aldehydes, two alcohols and one ketone. Monoterpenes increase their levels at pre-harvest and in response to UV-B in both, in vitro and field conditions. UV-B also improved the synthesis of some aldehydes, alcohols and ketones. These results along with others from the literature suggest that grape berries exposed to UV-B produce VOCs (mainly monoterpenes), which act as antioxidants that protect the tissues from UV-B itself and other abiotic and biotic stresses. Higher emission of monoterpenes was observed in the field experiments as compared with in vitro, suggesting the UV-B/PAR ratio is not a signal in itself.