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Olea europaea (L.) trees displaying leaf scorching symptoms, identical to those recently reported for olive trees colonized by Xylella fastidiosa in Southern Italy and also in Argentina, were observed in commercial orchards of two counties in Southeastern Brazil. PCR-based diagnosis using conserved primers for X. fastidiosa strains (RST31/33) and also specific to X. fastidiaosa subsp. pauca (CVC1/272-2 int) were positive for all symptomatic tested samples (n = 8 of 9), but no template was obtained using twigs from asymptomatic trees (n = 20). Bacterial colonies were isolated from symptomatic tissues on culture medium and confirmed by PCR using the set of primers specific to X. fastidiosa subsp. pauca. Comparative sequence analyses of seven MLST loci amplified from one tripled passaged colony (MFG01) perfectly matched with sequences of alleles leuA #7, petC #6, malF#8, cysG#10, holC#11, nuoL#8, and gltT#8, the allelic profile of Sequence Type-ST16, which is represented by the strain COF0238 isolated from Coffea arabica (L.) in Brazil (http://pubmlst.org/xfastidiosa/). Phylogenetic analysis placed the ST16 into subspecies pauca, but genetically closer to ST11 and ST13, both obtained from Citrus sinensis (L.) trees with citrus variegated chlorosis. The results confirm the association of olive plants showing leaf scorching with the presence of X. fastidiosa subsp. pauca , and represent the first report of this bacterium in Brazilian olive orchards., Phytopathologia mediterranea, 55 (1), ISSN:0031-9465, ISSN:1593-2095

This work focuses on the evaluation of flowering and vegetative growth of olive tree submitted to pruning and paclobutrazol application under field conditions with low temperatures during the winter. Two-years-old olive plant variety Grappolo 575, were submitted to light pruning, removing apical dominance, before treatments application. The treatments were organized in a 4×2 factorial scheme, respective to four PBZ concentrations tested: 0, 200, 400 and 800 mg L-1 of PBZ and two plants groups, with and without pruning, in randomized block with four replications. Paclobutrazol concentrations tested did not affect the olive tree flowering. The plant vegetative growth was reduced until 60 days after paclobutrazol application. Pruning resulted in stimulation of emission of vegetative shoots and reduction of flowering. Com o objetivo de avaliar o florescimento e o crescimento vegetativo da oliveira em plantas submetidas à poda e a aplicação do paclobutrazol foi conduzido um experimento em condições de campo com ocorrência de baixas temperaturas durante inverno. Plantas da variedade Grappolo 575, com dois anos de idade, foram submetidas a uma poda leve, retirando-se a dominância apical, antes da aplicação dos tratamentos, no mês de abril de 2009. Para a distribuição dos tratamentos, adotou-se o esquema fatorial 4×2, referente às quatro concentrações de paclobutrazol testadas e dois grupos de plantas, com e sem poda, em blocos casualizados com quatro repetições. As concentrações de paclobutrazol testadas não influenciaram no florescimento da oliveira. O crescimento vegetativo foi retardado até 60 dias após a aplicação do paclobutrazol. A poda estimulou a emissão de brotações vegetativas e reduziu o florescimento.