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In this research, physiological tests were carried out on the in vitro growth of four strains of ectomycorrhizal fungi (HECM) associated with Pinus leiophylla. The HECM strains were subjected to growth tests in different concentrations of glucose (10, 20, 30 and 40 g/L) and nitrogen sources (KNO3, (NH4)2HPO4 and urea). The variables of growth, final diameter, biomass, mean growth rate and biomass/area ratio were evaluated in the colonies. According to the statistical analysis, the Suillus pseudobrevipes strain (GF3246) presented a higher growth in the concentrations of glucose 20 and 30 (g/L); S. pseudobrevipes (GF3285) in KNO3 and (NH4)2HPO4; S. subtomentosus (GF3331) in 20 and 40 (g/L) and in S. variegatus (GF3349) the growth was indistinct among the treatments. The HECM strains presented different growth strategies according to their ability to explore, exploit and assimilate different nutrients. Due to the fact that the strains GF3246 and GF3349 presented higher of values biomass in low to medium concentrations of glucose and nitrogen sources, they are considered generalists and were selected to produce mycelial inoculum and induce mycorrhization and to evaluate their effectiveness on the survival and growth of Pinus leiophylla seedlings. [ABSTRACT FROM AUTHOR]

Floral visitors that act as pollinators are essential for sexual reproduction in angiosperms. Orchids (Orchidaceae), one of the families with the greatest species richness, present visual and chemical cues in their flowers to attract floral visitors, highlighting the shape, color and texture of the flowers, as well as the nectar, bait, pollen and floral aromas as rewards. Within the group, particular traits can be found that allow inferring the type of visitor that performs the pollination, that is, there are orchids with particular pollination syndromes. In this way, there are orchids whose flowers promote pollination by insects such as bees, wasps and butterflies, but there are species that are pollinated by birds (mainly hummingbirds). In this review, information is compiled that will allow orchids to be classified according to their floral visitors (pollinators) and that can serve as a guide to make inferences in the species that have not yet been described their visitors. [ABSTRACT FROM AUTHOR]

The soil microbiota is conformed by microorganisms present in the soil such as bacteria, fungi, algae, protists and archaea, mainly, which have a fundamental role in the mineralization and mobilization of nutrients, as well as in the protection of plants against pathogens, in addition to establishing mutualistic interactions in the rhizosphere. Therefore, microbiota play an important role in soil productivity, quality and structure. The objective of this bibliographic review was to Know the effect of anthropogenic activities on soil microbiota. From the review it was found that anthropogenic activities such as the use of agrochemicals, fires, erosion or change in land use have negatively affected the soil microbiota. There is evidence of a decrease in the diversity and abundance of microbial populations, in addition to the reduction or inhibition of the activity of microorganisms. This directly affects the functions of the microbiota (microbiome), since different microbial taxa influence soil physicochemical characteristics, biogeochemical cycles and plant population dynamics, although it is essential to conduct more exhaustive research to identify the effect of human activity. [ABSTRACT FROM AUTHOR]