Archivio Journal of Plant Pathology

Abstract:

To ascertain the presence of Pseudomonas syringae pv. actinidiae in Campania (southern Italy) field surveys were carried out since 2011 in all areas of kiwifruit (Actinidia deliciosa and A. chinensis) cultivation. In some orchards of Caserta, Benevento, Napoli and Salerno provinces, leaf spot- ting and twig wilting were observed, possibly indicating the occurrence of the pathogen, but no cankers along the trunk and main branches and plant collapse were seen. Gener- ally, the incidence of these symptoms varied from 3% to 20%. Isolation from symptomatic organs and identification procedures were done according to Ferrante and Scortichi- ni (2009, 2010). In parallel, with all samples, duplex PCR (Gallelli et al., 2011) and real-time PCR (Gallelli et al., 2014) were directly applied to plant tissues. The reference P.s. pv. actinidiae CRA-FRU 8.43 strain (Ferrante and Scortichini, 2010) was used as positive control. Pathogenicity tests were carried out on pot-grown, one-year-old plants of A. deliciosa cv. Hayward with representative isolates of P.s. pv. actinidiae obtained from all of the provinces (Ferrante and Scortichini, 2009). Bacterial isolates from all provinces were identified by PCR as P.s. pv. actinidiae. In addition, the successful inocula- tion of cv. Hayward demonstrated the pathogenicity of the representative isolates. The occurrence of the pathogen was also confirmed by the detection techniques applied directly to plant samples. P.s. pv. actinidiae was isolated in Napoli and Benevento provinces from cv. Hayward; in Salerno province from cvs Hayward and G3 Gold, and in Caserta province from cvs. Hayward, JinTao and Soreli.