Diversity of microorganisms associated to Ananas spp. from natural environment, cultivated and ex situ conservation areas

Abstract

Brazil is among the world's largest fruit producers, with emphasis on pineapples [Ananas comosus var. comosus (L.) Merril]. Although it is believed that Ananas spp. maintains relationships with a large range of phytopathogenic or beneficial microorganisms, studies of the microbial diversity associated with pineapple plants are still scarce. Therefore, the present work aimed to quantify and compare the diversity of culturable microorganisms considered in the literature as beneficial, existing in the rhizospheric soil and in internal tissues of Ananas spp. from three different environments: natural populations, commercial cultivation field and ex situ conservation area - Pineapple Germplasm Bank (Pineapple GB). Culture-dependent methods were applied to the microbial communities associated with Ananas spp., as well as molecular techniques based on BOX and ERIC markers for characterization of the samples and its fractions. These techniques allowed the grouping of isolates from different environments and fractions, such as those from soil, root and stem, in the same cluster, implying that there is correspondence in the distribution of beneficial microbiota (functional groups) from the soil to the aerial parts of plants. Furthermore, correlation analyses indicated the association of certain functional groups with the samples and that the plants are always requiring the same groups of microorganisms as in a certain network for sustaining adequate plant growth. The results enable a series of possible applications to this important crop species.