Aislamiento, caracterización y efecto de dos cepas de Rhizobium sobre el crecimiento en Lupinus mutabilis, bajo condiciones semicontroladas en suelos agrestes

Abstract

Abstract: The isolation and characterization of two strains ofRhizobium collected fromlupine plantations(Lupinus mutabilis)locatedin the provinces of Tungurahua and Cotopaxi, Ecuador, was carried out. The strains obtained were prepared in a suspension and encapsulated in sodium alginate and then inoculated in lupine seeds. It wasevaluated the effect of the strains, inoculation method and substrates on the vegetative development of the plants, under semicontrolled conditions in rugged soilsin the province of Tungurahua.For molecular identification, DNA extraction, amplification of the 16S region with specific primers, purification and sequencing were performed. Vegetative development was mainly influenced by the substrate used for germination of inoculated seeds. The hydrological characteristics of the Andean black soil substrate allowed the migration of the bacteroides towards the roots taking advantage of the capillary water retained in the substrate. The loamy loam soil substrate determined the lower vegetative development of the plant, as it was more susceptible to dehydration in the conditions under cover in which the researchwas carried out. The origin of the strain also influenced vegetative development, although it was not evident in nodulation. The strain originated in Tungurahua produced more vigorous plants, especially in interaction with the Andean black soil substrate.Nodulation was significantly influenced by the substrates sand (S1) and Andean black soil (S2), resulting in a higher number of nodules.