Biochar increases arbuscular mycorrhizal plant growth enhancement and ameliorates salinity stress

TY - JOUR

T1 - Biochar increases arbuscular mycorrhizal plant growth enhancement and ameliorates salinity stress

AU - Hammer, Edith

AU - Forstreuter, Manfred

AU - Rillig, Matthias C.

AU - Kohler, Josef

PY - 2015

Y1 - 2015

N2 - We examined combined effects of biochar, arbuscular mycorrhizal (AM) fungi and salinity on plant growth and physiology to test whether and how biochar influences AM fungi mediated growth and nutrition enhancements, and whether and how biochar provides amelioration in salt stressed soils. We carried out a full three-factorial greenhouse experiment with Lactuca sativa; and a second study with a wider range of biochar and salt additions to examine physicochemical effects on soil parameters. Biochar together with AM fungal inoculation resulted in an additional plant yield increase compared to each alone under non-saline conditions. In parallel with increased plant growth, we found increased uptake of P and Mn with AM fungi and biochar addition, but to a lesser extent than biochar-induced growth promotion. Both factors, but especially biochar alleviated salinity-caused growth depressions, and improved Na/K ratio in salinity stressed plants. Reduced Na uptake of plants and reduced conductivity in biochar-ameliorated soils suggest that a likely mechanism involves ion adsorption to biochar surfaces. Our results suggest that plants depend on symbiotic microorganisms to fully exploit biochar benefits in soils, suggesting avenues for joint management in agriculture. Biochar may be advantageous in saline soils, but long-term studies are required before recommendations should be given. (C) 2015 Elsevier B.V. All rights reserved.

AB - We examined combined effects of biochar, arbuscular mycorrhizal (AM) fungi and salinity on plant growth and physiology to test whether and how biochar influences AM fungi mediated growth and nutrition enhancements, and whether and how biochar provides amelioration in salt stressed soils. We carried out a full three-factorial greenhouse experiment with Lactuca sativa; and a second study with a wider range of biochar and salt additions to examine physicochemical effects on soil parameters. Biochar together with AM fungal inoculation resulted in an additional plant yield increase compared to each alone under non-saline conditions. In parallel with increased plant growth, we found increased uptake of P and Mn with AM fungi and biochar addition, but to a lesser extent than biochar-induced growth promotion. Both factors, but especially biochar alleviated salinity-caused growth depressions, and improved Na/K ratio in salinity stressed plants. Reduced Na uptake of plants and reduced conductivity in biochar-ameliorated soils suggest that a likely mechanism involves ion adsorption to biochar surfaces. Our results suggest that plants depend on symbiotic microorganisms to fully exploit biochar benefits in soils, suggesting avenues for joint management in agriculture. Biochar may be advantageous in saline soils, but long-term studies are required before recommendations should be given. (C) 2015 Elsevier B.V. All rights reserved.

KW - Biochar

KW - Black carbon

KW - Salt stress

KW - Mycorrhiza

KW - Soil improvement

KW - Salt

KW - sorption

U2 - 10.1016/j.apsoil.2015.07.014

DO - 10.1016/j.apsoil.2015.07.014

M3 - Article

VL - 96

SP - 114

EP - 121

JO - Applied Soil Ecology

JF - Applied Soil Ecology

SN - 0929-1393

ER -