First report of Pepo aphid-borne yellows virus on courgette in Italy

During monitoring for cucurbit viruses in greenhouses in the munici- palities of Torre del Greco (Napoli province, Campania) and Aversana (Salerno province, Campania) in September 2019 and October 2022, respectively, samples of commercial hybrids of courgette (Cucurbita pepo) showing symptoms of leaf yellowing and mosaics (Figure 1) were collected and stored as dried material. Three samples from 2019 and two samples from 2022, were inoculated mechanically onto courgette. Within two weeks, typical symptoms of Tomato leaf curl New Delhi virus (ToLCNDV), consisting of leaf crumpling, yellowing and downward curl- ing, were observed. ToLCNDV infection was confirmed by DAS-ELISA (Bioreba, Switzerland). This is not a new record for Campania since ToL- CNDV was detected in courgette in 2016 and causes a serious disease problem for cucurbit crops in this region. The samples were also checked for polerovirus infection by RT- PCR as follows. Total RNA was extracted from infected tissues using TRI-reagent (Sigma-Aldrich, USA) and RT-PCR was performed with polerovirus primers Pol-G-F and Pol-G-R (Knierim et al., 2014). A 1.1 Kb fragment was obtained from two samples, one sampled in 2019 and the other in 2022. These amplicons were sent to Geno- screen (Lille, France) for direct sequencing. The sequences obtained (GenBank Accession Nos. OP156930 and OP973153, respectively), encompassing part of the polerovirus RNA-dependent RNA poly- merase, intergenic region, coat protein and movement protein, shared a close relationship with Pepo aphid-borne yellows virus (PABYV) iso-