Effects of arbuscular mycorrhizal colonization on the biomass and bioenergy production of Populus × canadensis ‘Neva’ in sterilized and unsterilized soil

Abstract

Arbuscular mycorrhizal (AM) symbiosis can improve the growth of poplar, which is considered to be a bioenergy feedstock and a substitute for fossil fuels. Microbes in plant rhizosphere may affect the interaction between AM fungi and host plant. The role of AM fungi on the biomass and bioenergy production of poplar in the presence or absence of other soil microorganisms was less investigated. In this study, the effects of Rhizophagus irregularis and Glomus versiforme on the growth, root-absorbing area, chlorophyll content, gas exchange, total organic carbon (TOC) content, gross calorie value (GCV), lignin and cellulose content of Populus × canadensis ‘Neva’ in sterilized and unsterilized soil were evaluated. The results showed that AM symbiosis increased the biomass parameters such as stem length, ground diameter, dry weight, root-absorbing area, chlorophyll content and gas exchange capacity, as well as bioenergy parameters such as TOC content, GCV and lignin content of poplar seedlings, but did not affect the cellulose content. The extent of this enhancement varied within AM fungi species and soil conditions. The effect of AM was higher in sterilized soil than that in unsterilized soil, and the function of R. irregularis was greater than G. versiforme in sterilized soil, but lower in unsterilized soil. In general, G. versiforme exhibited higher applying potential in the biomass and bioenergy production of poplar.