Endophytic bacteria in Ilex paraguariensis shoot cultures: localization, characterisation, and control using isothiazolone biocides.

LUNA, C.; ACEVEDO, M.; COLLAVINO, M.; GONZÁLEZ, A.; MROGINSKI, L.; SANSBERRO, P.

IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY. PLANT

SPRINGER

Lugar: Berlin; Año: 2013 vol. 49 p. 326 - 332

1054-5476

Nodal segment explants of Ilex paraguariensis, collected from a greenhouse, were found to contain endophytic bacteria. After sub-culturing in bioreactors, 16 rRNA gene analyses and API biochemical tests were used to identify these bacteria, which were found to be Stenotrophomonas malthophilia. The presence of bacterial cells in intercellular spaces of stem cortical parenchyma could be detected in histo-sections using scanning electron microscopy. A range of commercial isothiazolone biocides were tested for their ability to repress the growth of gram-negative bacteria grown in liquid medium during the multiplication phase of temporal immersion systems. The best results were obtained with the addition of 0.75 ml l-1 DelcideTM TG (5-chloro-2-methyl-4-isothiazolin-3-one + 2-methyl-4-isothiazolin-3-one, 1.05% and 0.45%, respectively) to the culture media. The addition of this biocide resulted in 100% visibly clean cultures, without suppression of shoot growth.