EFFECT OF UV-C TREATMENT ON GENE EXPRESSION IN DIFFERENT STRAWBERRY FRUIT TISSUES

ROSLI HG; POMBO MA; FOLTA K; CIVELLO PM; MARTÍNEZ GA

Tucumán

Congreso; XLV Reunión ANUAL SAIB; 2009

SAIB

UV-C radiation of fruit has been tested to control postharvestdiseases and delay some ripening processes. Nevertheless, there islittle information concerning the mechanism by which beneficialUV-C induced changes occur. This work tests the effect of UV-Cradiation on gene expression in different fruit tissue levels. Ripestrawberry fruits (cv. Strawberry Festival) were irradiated with UV-C (4.1 kJ m-2). Control fruit received identical treatment with aPlexiglass filter. After treated, fruit were stored at 24 °C under whitelight, and samples from control (C) and treated (T) were taken atdifferent time points. The expression of an EXPANSIN gene(FaEXP2) was analyzed by Northern-blot. At 4 h the expressionwas found to be higher in control fruit, consequently this time pointwas chosen for further analysis. This difference was confirmed byqPCR, but no significant change could be detected for PECTINMETHYLESTERASE (FaPE1, AY324809) and b-1,3-GLUCANASE 2-1 (FaBG2-1, AY170375). Consequently, fruitwere irradiated, but after 4 h of storage in the dark, different tissueswere dissected (cortex and pith) and gene expression assessedseparately. In this case, differences could be detected, mainly in thecortical region of the fruit, being not evident or less marked in thepith. These results suggest a certain degree of localization of fruitresponse to UV-C radiation.