Interactions between a soil fungus, Trichoderma harzianum, and IIb metals?adsorption to mycelium and production of complexing metabolites

Abstract

Fungi are capable of accumulating metals and, in soil, such accumulation may influence metal speciation and transport. The interactions between a common soil fungus, Trichoderma harzianum, and IIb elements were studied in the present investigation. The accumulation of the metals zinc, cadmium and mercury by starved and non-starved mycelium at different pH was determined by a batch technique using radioactive tracers; uptake of the metals was found to be large, with respective distribution coefficients of about 103"5, 10 z'5 and 104.0 for zinc, cadmium and mercury, respectively. Metal accumulation by a starved system was largely independent of pH in the range 3-9, where in a non-starved system an increased accumulation of zinc (at 10 -8 M) was observed at low pH (3-5). Potentiometric titrations performed on the two systems revealed significant differences in acid capacities, i.e. values close to zero for the starved system and 500-800 meq kg -1 for the non-starved system. The maximum metal uptake was at least 50 mmol kg -1 at pH 6.5 (calculated from adsorption isotherms). The present findings suggests that in the non-starved system a metabolite is produced and then released when the pH is within a certain range.

Pyrene degradation and copper and zinc uptake byFusarium solaniandHypocrea lixiiisolated from petrol station soil

“…Altomare et al (1999) demonstrated that T. harzianum could solubilize insoluble minerals (MnO 2 , metallic zinc and calcium phosphate). Passive metal biosorption by T. harzianum has also been studied (Lokesha and Somashekar 1989;Krantz-Rulcker et al 1993;Ledin et al 1999) including a recent uranium biosorption study by Akhtar et al (2007). Therefore, the information gathered in this study indicates that H. lixii isolate no.…”

“…Passive metal biosorption by T . harzianum has also been studied (Lokesha and Somashekar 1989; Krantz‐Rulcker et al. 1993; Ledin et al.…”

Toward the Quantification of Confrontation (Dual Culture) Test: A Case Study on the Biological control of Pythium aphanidermatum with Trichoderma asperelloides

“…Effective Trichoderma isolates can play important roles in sustainable agriculture. These isolates would be able to (i) control phytopathogenic fungi [8], (ii) control plant nematodes [9][10][11][12], (iii) increase plant growth, development, and yield [13][14][15][16][17][18][19][20][21][22], (iv) induce plant systemic resistance of induced systemic resistance [22,23] acquired systemic resistance [24] against plant pests and diseases (v) increase plant resistance to abiological stresses [25,26], (vi) remediate polluted agricultural soils [7,27,28], (vii) improve soil environment [29][30][31][32], (viii) potentially control insect pests [33,34] and weeds [35][36][37].…”

Chromium, Cadmium, and Lead Dynamics During Winter Foliar Litter Decomposition in an Alpine Forest River

“…Furthermore, fungi in decomposing litter have been reported to be capable of accumulating significant amounts of the metals present in their external environment, even in unpolluted areas (Gadd and Griffiths, 1978;Berthelsen et al, 1995). As fungal mycelia can constitute a significant pool of organic material with a high capacity for heavy metal accumulation, they are thus likely to affect the overall mobility of a heavy metal in a litterbag (Krantz-Rülcker et al, 1993). This is an interesting finding that is not only meaningful for explaining the capacity of ecosystems for selfpurification but also significant for the control of hazardous materials.…”