Dual Inoculation of Arbuscular Mycorrhizal and Phosphate Solubilizing Fungi Contributes in Sustainable Maintenance of Plant Health in Fly Ash Ponds

Abstract

Fly ash is one of the residues produced during combustion of coal, and its disposal is a major environmental concern throughout coal-based powergenerated counties. Deficiencies of essential nutrients, low soil microbial activity, and high-soluble salt concentrations of trace elements are some of the concerns for reclamation of fly ash ponds. The effect of fly-ash-adapted arbuscular mycorrhizal (AM) fungi and phosphate solubilizing fungus Aspergillus tubingensis was studied on the growth, nutrient, and metal uptake of bamboo (Dendrocalamus strictus) plants grown in fly ash. Co-inoculation of these fungi significantly increased the P (150%), K (67%), Ca (106%), and Mg (180%) in shoot tissues compared control plants. The Al and Fe content were significantly reduced (50% and 60%, respectively) due to the presence of AM fungi and A. tubingensis. The physicochemical and biochemical properties of fly ash were improved compared to those of individual inoculation and control. The results showed that combination of AM fungi and A. tubingensis elicited a synergetic effect by increasing plant growth and uptake of nutrients with reducing metal translocation.

A high Mn(II)-tolerance strain, Bacillus thuringiensis HM7, isolated from manganese ore and its biosorption characteristics

“…The content of Fe and Al were reduced in plants. Babu and Reddy (2011) Bacillus sp. Brassica campestris L. The strain had high resistant to Cr, Zn, and Pb, and secreted organic acid.…”

Improvement of Ni phytostabilization by inoculation of Ni resistant Bacillus megaterium SR28C

“…The decreased metal accumulation in all plants tested in the presence B. megaterium SR28C indicates that inoculation of this strain seemed to be effective in improving Ni phytostabilization through reducing Ni accumulation in both root and shoot tissues. Though the observation indicates that B. megaterium SR28C reduced the metal uptake in plants with this metal binding feature, several authors have pointed out that microbial biosorption was not solely responsible for the reduced metal accumulation and/or translocation in plants (Vivas et al, 2003;Babu and Reddy, 2011). Recently, Park et al (2011) investigated the immobilization of Pb in soils by inoculating two phosphate solubilizing bacteria (Pantoea sp.…”

Heavy metal phytoremediation of a poplar clone in a contaminated soil in southern Italy

“…In fact, H + ions can replace HM cations adsorbed to soil particles . Root exudates, releasing substances such as siderophores, plant growth hormones and 1‐aminocyclopropane‐1‐carboxylic acid (ACC) deaminase, also promote the proliferation of rhizosphere microorganisms which in turn improve both plant growth and HM bioavailability …”

“…24 Root exudates, releasing substances such as siderophores, plant growth hormones and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, also promote the proliferation of rhizosphere microorganisms which in turn improve both plant growth and HM bioavailability. 20,[25][26][27][28][29][30][31][32][33][34][35][36][37][38] Thanks to an extensive root system, able to explore large soil volumes, high water uptake, rapid growth and large biomass production the Poplar genus (Populus spp) has proved effective in soil remediation from HMs. [39][40][41][42] Laboratory and field studies have shown the high variability between species and clones in their ability to reduce metal pollution; 43 poplars are generally able to accumulate Zn and Cd in foliar tissues; 44,45 however, their capability in Pb phytostabilization has also been demonstrated.…”