Mobilization of recalcitrant phosphorous and enhancement of pepper P uptake and yield by a new biocontrol and bioremediation bacterium Burkholderia cepacia CQ18

Abstract

Aims Phosphorus (P) is a finite resource and inoculation of phosphorus‐mobilizing bacteria (PMB) is a promising approach for the enhancement of soil P availability and plant P uptake. This drives scientists to search for the microbes effective in mobilizing legacy P in soils. Methods and Results The current incubation and greenhouse pot experiments were conducted to investigate P mobilization and pepper P uptake as affected by a new biocontrol and bioremediation bacterium Burkholderia cepacia CQ18. This bacterium converted Ca3(PO4)2, FePO4, AlPO4, and lecithin into soluble inorganic P in the culture solutions and increased available P (including water‐soluble P and Olsen P) in the soil. There were positive correlations between the soluble inorganic phosphorus and the exudates (protons, organic acids (oxalate and gluconate), siderophores and phosphatases) in culture solutions. Pepper plant biomass, fruit yield and P uptake changed in the sequence: chemical fertilizers plus bacterial inoculant >only chemical fertilizers >only bacterial inoculant >blank control. Conclusions Taking into account the wide spectrums of P mobilization and simultaneous production of acid, neutral and alkaline phosphatases at a given pH, B.cepacia CQ18 may be a potential PMB used in soils with wide pH ranges. The mechanisms employed by this bacterium in the solubilization of recalcitrant inorganic P could be the efflux of protons, organic acids (oxalate and gluconate) and siderophores. Phosphatases could be of utmost importance in the mineralization of the organic P. The production of siderophores and phosphatases by of B.cepacia CQ18 could thus be crucial for not only the antagonism against plant pathogens but also the mobilization of soil sparingly available P. Significance and Impact of the Study Burkholderia cepacia CQ18 could be potentially developed into a biofertilizer.

Potential of Burkholderia sp. IMCC1007 as a biodetoxification agent in mycotoxin biotransformation evaluated by mass spectrometry and phytotoxicity analysis

“…Phylogenetic analysis of 16S rRNA gene sequences of IMCC1007 revealed that this strain showed closest homology with members of the genus Burkholderia cepacia. Having said that Burkholderia cepacia possessed versatile metabolic capabilities and occupied wide range of ecological niches, various biotechnological applications including bioremediation of recalcitrant xenobiotics, biological control and plant growth promotion have gained their bene cial effects (Jung et al, 2018;Peng et al, 2020). To best of our knowledge, our isolated strain was different from reported literatures, thus enriching the diversity of FAdegrading bacteria.…”

Ceriporia lacerata HG2011 enhances P mobilization and wheat agronomic performance irrespective of P fertilization levels

“…The broths in the second five flasks were acidified by 0.1 ml 1 mol L −1 HCl. After centrifuging at 10,000 g for 10 min at 4°C, organic acids in the supernatants were measured by high‐performance liquid chromatography HPLC (Peng et al, 2020).…”

Phosphorus mobilization and improvement of crop agronomic performances by a new white‐rot fungus Ceriporia lacerataHG2011

“…In the assessment of inorganic P mobilization, five flasks of each P source were randomly selected when the fungal isolates were incubated for 0, 2, 4, 6 and 8 days. After mycelia were taken out, culture solutions together with the solids were sampled from each flask, acidified by 0.1 mol L −1 HCl (HCl:culture solution = 1:5, v:v) and passed through a syringe filter with 0.22‐μm openers for the analysis of LMWOA by high‐performance liquid chromatography as described by Peng et al 19 . Thereafter, the remnant culture broth was centrifuged for 10 min at 10 000 × g .…”

“…In the assessment of inorganic P mobilization, five flasks of each P source were randomly selected when the fungal isolates were incubated for 0, 2, 4, 6 and 8 days. After mycelia were taken out, culture solutions together with the solids were sampled from each flask, acidified by 0.1 mol L −1 HCl (HCl:culture solution = 1:5, v:v) and passed through a syringe filter with 0.22-μm openers for the analysis of LMWOA by high-performance liquid chromatography as described by Peng et al 19 Thereafter, the remnant culture broth was centrifuged for 10 min at 10 000 × g. A pH meter (PHSJ-5; INESA Scientific Instrument Co., Ltd, Shanghai, China; as also employed to detect soil and solution pH) was used to detect the pH values of supernatants from broths with inorganic P compounds. The collected mycelia were repeatedly rinsed with deionized water, oven-dried, weighed and digested with H 2 SO 4 -H 2 O 2 .…”