Growth promotion of common bean ( Phaseolus vulgaris L.) by a strain of Burkholderia cepacia under growth chamber conditions

• Published in: Soil biology & biochemistry 2001-11, Vol.33 (14), p.1927-1935
• Main Authors: Peix, A., Mateos, P.F., Rodriguez-Barrueco, C., Martinez-Molina, E., Velazquez, E.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Antifungal-activity; Biochemistry and biology; Biological and medical sciences; Burkholderia; Burkholderia cepacia; Chemical, physicochemical, biochemical and biological properties; Fundamental and applied biological sciences. Psychology; Fusarium; Growth promotion; Microbiology; Nitrogen-fixation; Phaseolus; Phaseolus vulgaris; Phosphate-mobilization; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Soil science
• ISSN: 0038-0717; 1879-3428
• DOI: 10.1016/S0038-0717(01)00119-5

We isolated a strain of Burkholderia cepacia (SAOCV2), which solubilizes inorganic phosphates and antagonizes Fusarium oxysporum f. sp. phaseoli and Fusarium solani in vitro, from soil. However, this strain does not have antibiotic activity against the bacteria tested in this study, which included bacterial plant pathogens and rhizobia. The efficacy of this strain to enhance the growth and P content in common bean was assesed in a soil traditionally cultivated with this species. In this soil, the common bean is affected by Fusarium. Our results show that the strain SAOCV2 was able to mobilize P efficiently in the common bean, so that its P content was increased by 44% with respect to uninoculated plants, whereas it was not significantly different with respect to the plants treated with fungicide. Also, the N content in plants inoculated with the strain SAOCV2 was significantly higher than in uninoculated plants. This result is correlated with a larger number of nodules in plants inoculated with SAOCV2 and in plants treated with fungicide and indicates that the inhibition of fungal growth enhances the bacterial community in the plant rhizosphere, including rhizobia. Our results suggest that the inoculation with strain SAOCV2 promotes the growth of common bean by several mechanisms, that include P mobilization, antagonism towards pathogenic species of Fusarium and, indirectly, by an increase in nodulation that may lead to an increase in N 2 fixation.