Influence of microbial inoculation with Rhizobium meliloti, Pseudomonas fluorescens and Glomus intraradices on forage quality of alfalfa (Medicago sativa L.)

Kostadinka Nedyalkova, Galina Petkova, Radka Donkova

Abstract: The effect of single and mixed microbial inoculation of alfalfa (Pleven 6 variety) with symbiotic nitrogen fixing bacteria Rhizobium meliloti 116 and Rhizobium meliloti 225, phosphate solubilizing bacteria Pseudomonas fluorescens and mycorrhizal fungus Glomus intraradices on alfalfa forage quality was studied. The assessment was made using the parameters of chemical composition, digestibility, energy and protein feeding values. A field experiment was carried out in 2018 on Chromic-Vertic Luvisol under irrigation. It was found that the mixed inoculation with Rhizobium meliloti 116+Pseudomonas fluоrescens had the highest complex forage quality evaluation. The forage was characterized with high crude protein (22.44%) and low fiber (15.35%) contents, high in vitro digestibility (70.81%), high energy (UFL-UFV 0.716-0.604) and protein (PBD-PDIN-PDIE 180- 141-103 g/kg) feeding values. Comparing to the control, all inoculations increased the crude ash content, and Pseudomonas fluorescens and Gl. intraradices+Rh. meliloti 116 increased the protein digestible in intestine depending on nitrogen (PDIN) value. Both single inoculations with Rhizobium meliloti 116 and Rhizobium meliloti 225 had no positive influence on forage quality parameters. The specificity of alfalfa- microbial inoculant relationships resulted in different effect on forage quality parameters.

Keywords: alfalfa; feeding value; Glomus intraradices; in vitro digestibility; Pseudomonas fluоrescens; Rhizobium meliloti

Date published: 2020-05-07