Abstract:
Coffee leaf rust is the main disease that causes significant losses in Coffea arabica. In Peru, this disease caused epidemics between 2008 and 2013 with production losses of 35 %. The objective was to identify H. vastatrix using a morphological and molecular approach based on a phylogenetic species concept. Coffee leaf samples with symptoms of chlorotic lesions with the presence of yellow uredospores at different severity stages of different cultivars were collected from 11 locations in the departments of Pasco and Junin during 2017-2018. DNA was purified as proposed by Cristancho and coworkers. The major subunit of ribosomal DNA was amplified with universal primers LR0R and LR5, and sequenced by Macrogen and deposited in GenBank. Sequences from the genera Achrotelium, Blastospora, Cystopsora, Hemileia, and Mikronegeria were included for phylogenetic analysis. The results showed that the rust was distributed in coffee growing regions of Pasco: Villa Rica (Catimor, Caturra, and Gran Colombia); Oxapampa (Yellow Caturra), and Junín: San Luis de Shuaro (Catimor), Chanchamayo (Catimor), San Ramón (Catimor), Vitoc (Caturra), Pichanaki (Caturra), Río Negro (Caturra), Pangoa (Yellow Caturra, Gran Colombia, Limani). It was also grouped into a single clade with isolated H. vastatrix from Mexico and Australia, suggesting that they come from a common ancestor. This is the first confirmed report using molecular barcoding of H. vastatrix in the central jungle of Peru.
