Pantoea stewartii subsp. stewartii an Inter-Laboratory Comparative Study of molecular tests and comparative genomes analysis of Italian strains.

Pantoea stewartii subsp. stewartii (Pss), is a quarantine pest originally from North America that has spread internationally through the trade of maize seeds. Control strategies include the use of resistant maize varieties, insecticide application, and reliable diagnostic methods. Accurate identification of Pss is particularly important to distinguish it from P. stewartii subsp. indologenes (Psi), a non-quarantine bacterium also associated with maize seeds.This study presents the results of interlaboratory comparisons assessing the performance of real-time PCR assays for the detection of Pss in seed samples. The assays were evaluated for diagnostic sensitivity (DSE), specificity (DSP), and accuracy (ACC). In addition, whole genome sequencing of Pss isolates from Italy was carried out to support molecular identification and improve knowledge of the genetic diversity of this pathogen.