Interactive effects of organic acids in the rhizosphere

Oburger, Eva; Kirk, G. J. D.; Wenzel, Walter W.; Puschenreiter, Markus; Jones, Davey L.

doi:10.1016/j.soilbio.2008.10.034

Cited by 162 publications

(96 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, our results show that malonate greatly increases soil respiration. This finding is consistent with that of Oburger et al (2009), who found malonate did not inhibit microbial activity when added to a range of soil types in solutions also containing malate, citrate and oxalate.…”

Section: Citrate and Malonate Enhanced Microbial Activity In Uncontamsupporting

confidence: 91%

“…Carboxylates may act as bio-stimulating agents in the degradation of PHCs through the provision of a labile carbon source that supports increased microbial growth and activity. When added to soils, carboxylates are rapidly degraded by soil microorganisms, with up to 80 % mineralized to CO 2 within 24 h, depending upon the carboxylate added and the soil type (Evans, 1998;Ström et al, 2001;Hashimoto, 2007;Oburger et al, 2009;Fujii et al, 2010;Ryan et al, 2012). In addition, carboxylates have the capacity to enhance soil phosphorus supply and, hence, microbial growth and activity through phosphate desorption either due to anion exchange or their ability to chelate to metal cations (e.g., Al 3+ , Fe 3+ and Ca 2+ ) (Jones and Darrah, 1994;Ryan et al, 2001;Shane and Lambers, 2005).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Citrate and malonate increase microbial activity and alter microbial community composition in uncontaminated and diesel-contaminated soil microcosms

Martin

George

Price

et al. 2016

SOIL

View full text Add to dashboard Cite

Abstract. Petroleum hydrocarbons (PHCs) are among the most prevalent sources of environmental contamination. It has been hypothesized that plant root exudation of low molecular weight organic acid anions (carboxylates) may aid degradation of PHCs by stimulating heterotrophic microbial activity. To test their potential implication for bioremediation, we applied two commonly exuded carboxylates (citrate and malonate) to uncontaminated and diesel-contaminated microcosms (10 000 mg kg −1 ; aged 40 days) and determined their impact on the microbial community and PHC degradation. Every 48 h for 18 days, soil received 5 µmol g −1 of (i) citrate, (ii) malonate, (iii) citrate + malonate or (iv) water. Microbial activity was measured daily as the flux of CO 2 . After 18 days, changes in the microbial community were assessed by a community-level physiological profile (CLPP) and 16S rRNA bacterial community profiles determined by denaturing gradient gel electrophoresis (DGGE). Saturated PHCs remaining in the soil were assessed by gas chromatography-mass spectrometry (GC-MS). Cumulative soil respiration increased 4-to 6-fold with the addition of carboxylates, while diesel contamination resulted in a small, but similar, increase across all carboxylate treatments. The addition of carboxylates resulted in distinct changes to the microbial community in both contaminated and uncontaminated soils but only a small increase in the biodegradation of saturated PHCs as measured by the n-C17 : pristane biomarker. We conclude that while the addition of citrate and malonate had little direct effect on the biodegradation of saturated hydrocarbons present in diesel, their effect on the microbial community leads us to suggest further studies using a variety of soils and organic acids, and linked to in situ studies of plants, to investigate the role of carboxylates in microbial community dynamics.

show abstract

Section: Citrate and Malonate Enhanced Microbial Activity In Uncontamsupporting

confidence: 91%

Section: Introductionmentioning

confidence: 99%

Citrate and malonate increase microbial activity and alter microbial community composition in uncontaminated and diesel-contaminated soil microcosms

Martin

George

Price

et al. 2016

SOIL

View full text Add to dashboard Cite

show abstract

“…Apart from respiration, photosynthesis and nitrogen metabolism, organic acids are said to have vital roles in helping the plant to adapt to nutrient deficiencies and metal stress [33]. We have recorded the pyru J. Saha et al In our study we observed an elevation in the organic acid contents in the test seedlings treated with sodium arsenate.…”

Section: Effect On the Intermediates Of Krebs Cyclesupporting

confidence: 54%

Influence of Arsenate and Phosphate on the Regulation of Growth and TCA Cycle in the Rice (<i>Oryza sativa</i> L.) Cultivars IR64 and Nayanmani

Saha¹,

Dutta²,

Biswas³

2017

AJPS

View full text Add to dashboard Cite

The influence of arsenate and phosphate on the growth and respiration of 21 days old seedlings in two cultivars of rice, viz., IR64 and Nayanmani was studied. As arsenate and phosphate are similar in their chemical configuration and the latter is preferentially taken up by the phosphate transporters, it results in a competitive inhibition of arsenate uptake in presence of phosphate. Increasing concentrations of sodium arsenate (25 µM, 50 µM and 100 µM) hindered the growth in both the cultivars, with cv. IR64 being more severely affected than cv. Nayanmani. There was an elevation in the levels of organic acids measured in both the cultivars, accompanied by a reduction in the activities of the dehydrogenases of the TCA cycle, viz., pyruvate dehydrogenase, isocitrate dehydrogenase, succinate dehydrogenase and malate dedrogenase under arsenic treatment alone. Also, an elevation in the activities of citrate synthase and fumarase enzymes was noticed in both test seedlings with increasing concentrations of arsenic. These alterations were more prominent in cv. IR64 than in cv. Nayanmani. On joint application of phosphate along with arsenate, amelioration of the toxic effects of arsenate was observed to some extent, resulting in an overall revival of respiration leading to improved growth and metabolism.

show abstract

“…In this case, protonation of a mineral surface can weaken metal-oxygen bonds Xu and Gao 2008). Organic acids may also chelate with formerly organic-bound surface cations (Golubev et al 2006;Wang et al 2014;Kleber et al 2015) or compete with binding sites and directly displace MAOM via ligand exchange (Oburger et al 2009;Keiluweit et al 2015). These processes can affect both metal oxides and silicate clays, although the potential for MAOM destabilization through this mechanism is generally greater among the former (Golubev et al 2006).…”

Section: Direct Destabilization Pathwaysmentioning

confidence: 99%

Minerals in the rhizosphere: overlooked mediators of soil nitrogen availability to plants and microbes

et al. 2018

View full text Add to dashboard Cite

Despite decades of research progress, ecologists are still debating which pools and fluxes provide nitrogen (N) to plants and soil microbes across different ecosystems. Depolymerization of soil organic N is recognized as the rate-limiting step in the production of bioavailable N, and it is generally assumed that detrital N is the main source. However, in many mineral soils, detrital polymers constitute a minor fraction of total soil organic N. The majority of organic N is associated with clay-sized particles where physicochemical interactions may limit the accessibility of N-containing compounds. Although mineralassociated organic matter (MAOM) has historically been considered a critical, but relatively passive, reservoir of soil N, a growing body of research now points to the dynamic nature of mineral-organic associations and their potential for destabilization. Here we synthesize evidence from biogeoscience and soil ecology to demonstrate how MAOM is an important, yet overlooked, mediator of bioavailable N, especially in the rhizosphere. We highlight several biochemical strategies that enable plants and microbes /doi.org/10.1007/s10533-018-0459-5 to disrupt mineral-organic interactions and access MAOM. In particular, root-deposited low-molecularweight exudates may enhance the mobilization and solubilization of MAOM, increasing its bioavailability. However, the competitive balance between the possible fates of N monomers-bound to mineral surfaces versus dissolved and available for assimilation-will depend on the specific interaction between mineral properties, soil solution, mineral-bound organic matter, and microbes. Building off our emerging understanding of MAOM as a source of bioavailable N, we propose a revision of the Schimel and Bennett (Ecology 85:591-602, 2004) model (which emphasizes N depolymerization), by incorporating MAOM as a potential proximal mediator of bioavailable N.123 Biogeochemistry (2018) 139:103-122 https:/

show abstract

Interactive effects of organic acids in the rhizosphere

Cited by 162 publications

References 31 publications

Citrate and malonate increase microbial activity and alter microbial community composition in uncontaminated and diesel-contaminated soil microcosms

Citrate and malonate increase microbial activity and alter microbial community composition in uncontaminated and diesel-contaminated soil microcosms

Influence of Arsenate and Phosphate on the Regulation of Growth and TCA Cycle in the Rice (<i>Oryza sativa</i> L.) Cultivars IR64 and Nayanmani

Minerals in the rhizosphere: overlooked mediators of soil nitrogen availability to plants and microbes

Contact Info

Product

Resources

About

Interactive effects of organic acids in the rhizosphere

Cited by 162 publications

References 31 publications

Citrate and malonate increase microbial activity and alter microbial community composition in uncontaminated and diesel-contaminated soil microcosms

Citrate and malonate increase microbial activity and alter microbial community composition in uncontaminated and diesel-contaminated soil microcosms

Influence of Arsenate and Phosphate on the Regulation of Growth and TCA Cycle in the Rice (&lt;i&gt;Oryza sativa&lt;/i&gt; L.) Cultivars IR64 and Nayanmani

Minerals in the rhizosphere: overlooked mediators of soil nitrogen availability to plants and microbes

Contact Info

Product

Resources

About

Influence of Arsenate and Phosphate on the Regulation of Growth and TCA Cycle in the Rice (<i>Oryza sativa</i> L.) Cultivars IR64 and Nayanmani