Resumen

MALDONADO-BONILLA, Luis David et al. Strain of Pseudomonas syringae causes bacterial leaf spot in marigold plants (Tagetes erecta) in Mexico. Rev. mex. fitopatol [online]. 2021, vol.39, n.3, pp.493-502.  Epub 13-Dic-2021. ISSN 2007-8080.  https://doi.org/10.18781/r.mex.fit.2104-5.

Marigold (Tagetes erecta) is an Asteraceae plant commonly used as an ornamental and ceremonial flower during the fall season in Mexico. Marigold plants cultivated in the field presented bacterial leaf spot disease symptoms. A bacterial strain that potentially causes spot disease was isolated. The main goal of this research was to classify this bacterium and assess its pathogenicity towards marigold and other plant species. The biochemical profiling identified this strain as Pseudomonas syringae LF2012. The phylogenetic analysis of the 16S rRNA gene revealed a close relation with Pseudomonas genomospecies. The I-CeuI macro-restriction profile of the chromosomal confirmed its high degree of similarity with distinct P. syringae pathovars. P. syringae LF2012 causes spot disease when inoculated by spray in marigold leaves. Infection assays towards plants from other families (Asteraceae, Brassicaceae, Amaranthaceae, Poaceae y Solanaceae) suggested that disease might be limited to marigold plants. Furthermore, this strain causes hypersensitive-like responses in Nicotiana tabacum leaves.

Palabras llave : bacteria; phytopathogen; virulence; hypersensitive response; 16S rRNA.