Caracterização fenotípica e molecular de isolados de nódulos de jurema preta (Mimosa tenuiflora) cultivada em solos de áreas de Caatinga

Abstract

The symbiosis established between native rhizobia and forage legumes, essential to biological nitrogen fixation (BNF), is fundamental to the cycling of nutrients, providing viable alternative to agricultural systems in semi-arid. These studies can promote ecological and taxonomic knowledge of rhizobia in semiarid regions, and generate information on the functionality of these bacteria in Semi-Arid environments. The objective of this research was to perform the isolation and evaluation of the cultural diversity of rhizobia isolated from nodules of forage species Mimosa tenuiflora (Wild. Poir), grown in different soils of the semiarid region of Pernambuco state region. Soil samples for cultivation of plants in the greenhouse were collected in the municipalities of Sertânia, São Bento and Arcoverde. 216 nodules were collected, isolated and peaked amid LMA and proceeded to cultural characterization of isolates being observed in each of the individual characteristics of the colonies: growth time for viewing the colonies, shape and diameter of the colonies, gum production, coloration of the colonies and change of pH. The data were submitted to cluster analysis to observe similarity. Isolated from nodules set in Mimosa roots tenuiflora naturally occurring in soils of the areas of pernmbucanos municipalities have rapid growth and mostly did not change the pH of the medium, feature normally found in the genus Burkholderia predominant colonization of Minosa tenuiflora. Isolates of Arcoverde and São Bento produce greater amount of exopolisacarídeos (mucus) than the Sertânia. From the Jaccard coefficient isolates were grouped into 31 distinct groups showing a high morphological diversity.