Effect of Inoculation of Earthworms and Soil Microorganisms on Soil Structure and Productivity of Alfalfa

The paper deals with exploration the influence of earthworms and soil microorganisms on soil structure and productivity of alfalfa. The observation was carried out on Chromic-Vertic Luvisols (fine texture) from Sofia field (Bulgaria) in pot experiment. The inoculations were made with three ecological groups of lumbrids: anecic (Lumbricus terrestris), epigeic (Eisenia fethida) and endogeic (Aporrectodea rosea, Aporrectodea caliginosa and Octolasion lacteum) earthworms. The inoculation with soil microorganisms was provided with nitrogen-fixing bacteria from genus Rhizobium. The soil structure of studied treatments was characterized by indicators derived from the soil water retention curve and total porosity. The most pronounced effect of inoculations of earthwоrms and microorganisms was found in the volume of macropores which increased with depth while in the control variant it decreased with depth. The results showed that interaction between earthworms and soil microflora increased the biomass of alfalfa. Our study demonstrated that earthworms and soil microorganism have positive effect on the aeration of roots and yield of forage crops.

Keywords:

Alfalfa, Earthworms, Forage crops Soil microorganisms,

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