First report of chickpea chlorotic dwarf virus in pepper in Tunisia and in Mediterranean countries

Pepper (Capsicum annuum) is one of the main crops grown and consumed in Tunisia. The main production areas are located in Cap Bon, Center and Sahel regions. Chickpea chlorotic dwarf virus (CpCDV, genus Mastrevirus, family Geminiviridae) has a monopartite single-stranded circular DNA genome, a very broad host range and is reported in many tropical and subtropical countries. CpCDV was reported in Tunisia on chickpea, watermelon and tomato (Zaagueri et al. 2019), crops that may have an overlapping growing season with pepper. During 2019 and 2020 surveys, leaf and fruit samples showing virus-like symptoms were collected from pepper plants. Ten independent plants were sampled (eight leaf and four fruit samples) and tested in end-point CpCDV-specific PCR following total nucleic acid extraction. The expected amplification product of 1376 bp including the large intergenic region, the V2 gene and partial C1 and V1 genes of the CpCDV genome was detected in all leaf samples tested (n = 8) and in 3 out of 4 fruits. CpCDV infection was confirmed by dot-blot hybridization using a DIG-labelled probe specific for CpCDV V1 gene following rolling circle amplification (TempliPhi Amplification kit, Sigma-Aldrich). Nucleotide sequences obtained from two samples were submitted to GenBank (OM735808 and OM735809). The two sequences showed 99.8% identity to each other and more than 99% identity with sequences of Tunisian strain A CpCDV isolates from watermelon (KX580024) and tomato (MK116546). Other strains of CpCDV have been reported infecting pepper in Oman (Akthar et al. 2014) and India (Byun et al. 2014) causing stunting and upward leaf curling. CpCDV strain A on pepper in Tunisia is apparently producing mild atypical symptoms. To our knowledge, this is the first report of CpCDV infecting pepper in Tunisia and in the Mediterranean area.