Morphological and molecular identification of Phytophthora cinnamomi Rands as causal agent of Crown and root rot in Blueberry (Vaccinium corymbosum) in Peru

The Blueberry production in Peru has had rapid growth in the last five years, from having no area of more than 3050 hectares at present. As a result of this increase, many pathologic plant problems have appeared among them Phytophthora sp. causing plants with symptoms of wilt, reddish of lower leaves, regressive death, rotting of roots and crown of different production areas of Peru. However, there is no identification reported in Peru. Therefore, this study was conducted in the Plant Pathology Clinic of the Universidad Nacional Agraria La Molina with the objective of to identify the species of Phytophthora causing Crown and root rot isolated from blueberry in Peru. Four isolates from the blueberry´s field were identified by morphological, molecular and pathogenically features. All the isolates formed corralled-type colonies with hyphal swelling on PDA and V-8 agar and produced obpyriform or ellipsoidal sporangia and globes chlamydospores. The internal transcribed spacer (ITS) of rDNA was amplified and sequenced with primer ITS1/ITS4 to confirm the identification, All the ITS nucleotide sequences from isolated obtained were submitted at GenBank of NCBI (Number Accession MH777152 to isolate AR-1, MH777151 to isolate AR-2, MH777150 to isolate AR-4, and MH777149 to isolate AR-3). Each one of the sequences showed 100% of homology with sequences of reference of P. cinnamomi in GenBank. Pathogenicity tests showed symptoms of redness and yellowing and root and Crown rot on Blueberry cv. Biloxi after 30 days of inoculation. Finally, concluded that P. cinnamomi is the species causing Crown and root rot in Blueberry in Peru. To our knowledge, this is the first report of P. cinnamomi on blueberry in Peru.