DETECTION OF Clavibacter michiganensis subspecies michiganensis IN TOMATO OF THE STATE OF SONORA, MÉXICO

Abstract

Bacterial canker caused by Clavibacter michiganensis subspecies michiganensis (Cmm) is one of the major limitations of tomato (Lycopersicon esculentum Mill.) production in the world. In México the tomato production represents 73 % of the vegetable production. Northwestern México, specifically the State of Sonora, has been affected by diseases that have caused losses of up to 100 %. The objective of this study was to detect Cmm in tomato in the State of Sonora, México. Seed, leaves, stems and fruits were collected in nine localities of the state, either in greenhouses, shade houses or opencast fields. Cmm was detected through ELISA, by culture in YDC and NBY, followed by identification of colonies by biochemical tests and by PCR. A 279 bp fragment of the intergenic spacer (16S-23S) specific of the ribosomal operon of Cmm was amplified. Another fragment of approximately 480 bp of 16S rRNA was amplified and sequenced, which showed a 99 % homology with sequences of Cmm from public databases. The presence of the bacteria in tomato represents a risk for tomato producers. Therefore, it is necessary to carry out tests on imported seeds, to prevent its introduction to the country.