CONICET | Buscador de Institutos y Recursos Humanos

Yellow leaf disease, caused by Sugarcane yellow leaf virus (SCYLV), is spread worldwide but its incidence and distribution in Argentina remain unclear. The aims of this study were to analyse SCYLV distribution in the main sugarcane production area in Argentina, characterize the virus, determine the correlation between virus presence and disease symptoms and evaluate the parental collection of the Sugarcane Breeding Program (SBP) of the Estación Experimental Agroindustrial Obispo Colombres (EEAOC) using different diagnostic techniques to detect SCYLV. One hundred and forty-six sugarcane leaf samples with and without symptoms were collected from commercial cultivars and advanced breeding clones at final testing stages of selection of the SBP in 2011 and 2012 in Tucumán Province. In addition, samples from parents used in SBP were collected during 2013, 2015, 2016 and 2017 to compare molecular and serological diagnostic techniques. SCYLV was detected by RT-PCR in 29 out of 146 samples from Tucumán, and was widely distributed among commercial sugarcane cultivars, both in symptomatic and asymptomatic plants. A low but statistically significant positive correlation between virus detection and disease symptoms was found, even though 83% of the positive samples were asymptomatic. BRA-PER was the only virus genotype detected. Phylogenetic analysis of the SCYLV-CP gene allows clustering of strains as well as ability to distinguish among individual isolates. Comparison of diagnostic methods concluded that RT-PCR using SCYLVf1/r1 primers were more sensitive than the YLS111/462 pair, and that molecular diagnosis was more sensitive than TBIA. We also identified potential SCYLV-resistant genotypes in the EEAOC parent collection, as some genotypes remained disease-free throughout the experimental period