02370naa a2200253 a 450000100080000000500110000800800410001910000190006024500760007926000090015530000130016452016880017765000080186565000140187365000160188765300240190365300200192770000160194770000170196370000180198070000160199870000170201477300850203115402652019-11-13       2004    bl uuuu     u00u1 u    #d1 aBRONOMELLI, A.  aResponse of grapevine defenses to UV-C exposure.h[electronic resource]  c2004  ap. 51-59  aAbstract: The defense potential of a tolerant American Yitis rupestris cultivar (Rupestris du Lot) and a susceptible European Vitis vinifera cultivar (Chardonnay) in response to UV-C irradiation was investigated, The expression of eight defense-related genes coding for enzymes of the phenylpropanoid pathway (phenylalanine ammonia Jyase and stilbene synthase), the octadecanoid pathway (lipoxygenase), and pathogenesis-related proteins (class I and Ill chitinases, B-I ,3-glllcanase, cIass 6 pathogenesis-related protein, and class 10 pathogenesis-related protein) was followed by real-time reverse transcription polymerase chain reaction (RT-PCR). Phenolic compound accumulation was monitored by microscopic observation. Accumulation of resveratrol, a major grapevine phytoalexin, was evaluated by HPLC, and chitinase and fi-I ,3- glucanase enzyme activities were measured. Both grapevine species responded to UV-C treatment by enhancement of defense mechanisms. Intensity of some defense responses was correlated with tolerance to diseases, as previously described for stilbene accumulation: the tolerant species responded more intensely to UV-C exposure than the susceptibJe one. UV-C irradiation is a practical and reproducible method for inducing grapevine defense responses and can be useful in determining the defense potentiaJ of grapevine cultivars. Keys words: grapevine, UV-C (200 to 280 nm), defense mechanisms, real-time RT-PCR Abbreviations: class I chitinase (Chitlb); class III chitinase (CH3); Iipoxygenase (LOX); phenylalanine ammonia lyase (PAL); class 6 pathogenesis-related protein (PR-6); class 10 pathogenesis-reJated protein (PR-IO); stilbene synthase (StSy)  aUva  aVariedade  aViticultura  aMecanismo de defesa  aRadiação UV-C1 aMERCIER, L.1 aFRANCHEL, J.1 aBAILLIEUL, F.1 aBENIZRI, E.1 aMAURO, M.-C.  tAmerican Journal of Enology and Viticulture, Davisgv. 55, n. 1, p. 51-59, 2004.