Identification of volatile compounds produced by the bacteriumBurkholderia tropicathat inhibit the growth of fungal pathogens

Abstract

It has been documented that bacteria from the Burkholderia genera produce different kinds of compounds that inhibit plant pathogens, however in Burkholderia tropica, an endophytic diazotrophic and phosphate-solubilizing bacterium isolated from a wide diversity of plants, the capacity to produce antifungal compounds has not been evaluated. In order to expand our knowledge about Burkholderia tropica as a potential biological control agent, we analyzed 15 different strains of this bacterium to evaluate their capacities to inhibit the growth of four phytopathogenic fungi, Colletotrichum gloeosporioides, Fusarium culmorum, Fusarium oxysporum and Sclerotium rolffsi. Diverse analytical techniques, including plant root protection and dish plate growth assays and gas chromatography-mass spectroscopy showed that the fungal growth inhibition was intimately associated with the volatile compounds produced by B. tropica and, in particular, two bacterial strains (MTo293 and TTe203) exhibited the highest radial mycelial growth inhibition. Morphological changes associated with these compounds, such as disruption of fungal hyphae, were identified by using photomicrographic analysis. By using gas chromatography-mass spectroscopy technique, 18 volatile compounds involved in the growth inhibition mechanism were identified, including α-pinene and limonene. In addition, we found a high proportion of bacterial strains that produced siderophores during growth with different carbon sources, such as alanine and glutamic acid; however, their roles in the antagonism mechanism remain unclear.

Antifungal Appraisal of Burkholderia Gladioli Strain Vimp03 (Jq867372) Against Ceratocystis Paradoxa

“…agaricicola against Fusarium oxysporum and R. solani. The Burkholderia tropica was documented to inhibit the growth of phytopathogenic fungi such as Colletotrichum gloeosporioides, Fusarium culmorum, F. oxysporum, and S. rolfsii [19].…”

Microbial Consortium of Plant Growth-Promoting Rhizobacteria Improves the Performance of Plants Growing in Stressed Soils: An Overview

“…Toluene, dimethyl disulfide, and terpenoid compounds like α-pinene and limonene are the other volatiles produced by Burkholderia sp. (Tenorio-Salgado et al 2013). …”

Identificación molecular de bacterias asociadas a plantas ornamentales producidas in vitro

“…oryzae con sinónimos Enterobacter guangdongense, Enterobacter oryzae (UniProt Taxonomy, 2014), se ha reportado como una bacteria que fija nitrógeno en las raíces de arroz (Peng et al, 2009), y por el momento no se tiene reportada como fitopatógena. En este mismo sentido, la bacteria Burkholderia tropica, también es considerada fijadora de nitrógeno, con importantes aplicaciones agro biotecnológicas como la actividad antifúngica para el biocontrol de hongos fitopatógenos de interés agrícola (Tenorio-Salgado et al, 2013).…”

“…oryzae, synonymous with Enterobacter guangdongense, Enterobacter oryzae (UniProt Taxonomy, 2014), has also been reported as a bacteria that fixates nitrogen in roots of rice plants (Peng et al, 2009), and so far it has not been reported as phytopathogenic. In this same sense, the bacteria Burkholderia tropica is also considered nitrogen fixating, with important agro-biotechnological applications such as antifungal activity for the biocontrol of phytopathogenic fungi of agricultural interest (Tenorio-Salgado et al, 2013). P. cypripedii, the previous name for which was Erwinia cypripedii (UniProt Taxonomy, 2014), produces the disease called orchid brown rot (Plantwise, 2014); it is a bacteria that affects plants such as the papaya tree (Carica papaya) and different types of orchids, such as the lady slipper or Venus's slipper (Paphiopedilum), the orchid var.…”