Curtobacterium, A Foliar Pathogen Isolated from Maize in Central Argentina

Plant pathogens, such as fungi, bacteria, and viruses, can cause serious damage to crops and significantly reduce yield and quality. Bacterial diseases of agronomic crops, however, have been little studied. The present study aims to isolate and identify bacteria recovered from symptomatic maize (Zea mays) leaves collected from field samples in the province of Cordoba, Argentina. Bacterial strains were identified using whole-cell matrix-assisted laser-desorption-ionization–time-off light mass spectrometry and 16S rDNA sequencing. Members of the genera Exiguobacterium and Curtobacterium were dominant in the studied vegetal material. Two strains (RC18-1/2 and RC18-3/1) were selected for further studies. The pathogenicity test showed that plants inoculated with Curtobacterium sp. RC18-1/2 exhibited the same symptoms as those previously detected in the field. To our knowledge, this study provides the first evidence about the isolation of a Curtobacterium pathogenic strain in maize. Effective crop disease management will require the use of integrated strategies, such as resistant cultivars and/or biocontrol agents.