Caracterização fenotípica e genotípica in vitro de polytrichum juniperinum hedw. Submetido ao estresse por ferro

Abstract

The mechanisms of changes in response to iron deficiency and toxicity are described only by plants for superior strain, and usually of economic importance, and these studies still lacking for most plants of ancient lineage of land plants. This work aimed to evaluate the morphological changes and the genetic variability of Polytrichum juniperinum Hedw. in response to the treatment using various concentrations of Fe-EDTA in vitro. In addition to testing the transfer of EST-SSR markers between Physcomitrella patens (Hedw.) Bruch & Schimp. and P. juniperinum for the use of primers successfully transferred in genotypic evaluation of samples subjected to different concentrations of iron. For the morphological characterization, the moss was grown in treatments containing 0ml.L-1 5ml.L-1 10ml.L-1 and 50ml.L-1 of the Fe-EDTA. In the 40 and 45 days, crops were evaluated. In the second study, alterations in the genetic variability of P. juniperinum subjected to different treatments was assessed using SSR and ISSR regions. The results indicated that the species is sensitive to high concentrations of iron, reducing the number of gametophytes regenerated or even inhibiting these and causing changes in color of the explants. In the deficiency of the metal, the plant had normal development indicating that the absence of the metal is not a limiting factor for its development. Starting from the phenogram obtained was observed that the control treatment differed from the others indicating that the plant had alteration in its genetic variability, which can be inferred that the species under stress conditions may be expressing genes involved in strategy I and II regulation of the iron homeostasis. Thus, this study suggests that plant species P. juniperinum can undergo morphological and genotypic changes by the high concentration of iron in soils that are under heavy metal pollution, including the Antarctic soil. Can also be used as a bioindicator of sites with little available iron, and a model for molecular studies involving processes of iron homeostasis.