Genus-Specific Molecular Markers for In Vitro Detection of Corinectria Forest Pathogens

Canker disease caused by Corinectria constricta has resulted in significant losses of Pinus radiata for the Chilean forestry industry in recent years. Accurate and prompt detection and identification of the pathogen is essential in this context. In this study, a set of molecular markers was developed using multiple alignments of the actin-1 (ACT) and β-tubulin (Btub) gene regions to detect the genus Corinectria in vitro. The designed molecular markers were evaluated for specificity and sensitivity using conventional PCR assays, which successfully differentiated Corinectria species from other closely related species and fungal pathogens of P. radiata. The results showed that the molecular markers were able to detect Corinectria genus with high specificity and sensitivity, with Act-31F/Act-543R detecting 0.1 ng/µL of template DNA and Btub/BtubR detecting 0.05 ng/µL. This study represents the first report of specific molecular markers being developed to detect/identify the genus Corinectria in vitro, and the use of these markers is suggested for the timely detection of the pathogen in P. radiata plantations.