Características morfofisiológicas, propagativas e atividade antifúngica de óleos essenciais foliares de três espécies de Aniba (Lauraceae) arbóreas

Abstract

Aromatic Lauraceae species present high potential in fragrant flora of the Amazon and are prominent renewable sources for the production of aromatic essences. The importance of these species and how they are exploited justifies the necessity for morphological and anatomical studies, because have an apparent similarity between them leaf morphological characters. Additionally, ecophysiological studies are also needed to determine the influence of the primary factors on survival, adaptation, growth and development, in order to provide elements for the establishment of a seedling production system and/or biomass incorporation. The success of farming depends, among other factors, practices to ensure the establishment of seedlings in environments that initially may impose conditions of stress, especially water and light stress. In addition, the increasing pressure from environmental agencies against predatory extractive activities, plus the intensification of the actions of consumers against the use of synthetic pesticides has led to increased market demand for the production and use of biofungicides with low impact on the environment and human health. Thus, studies that characterize morphological and anatomical and physiological species of Aniba (Lauraceae), aiming of bioprospecting secondary metabolites and proteins that are active against fungi, as well as in vitro propagation of these species can increase the availability of planted individuals, contributing effectively to develop new technologies that add more value and sustainable exploitation of these Amazonian species. This study was conducted in order to contribute to the propagation techniques of Aniba rosaeodora, Aniba canelilla and Aniba parviflora with the initiatives to prospecting and sustainable use of essential oils and other metabolites with potential antifungal activity. Given these assumptions, a set of experiments were conducted at the Laboratory of Plant Physiology and Biochemistry - INPA and from morpho-structural studies and functional seedlings of three species of Aniba, seeking to understand biological and applied aspects about some Lauraceae tree Amazon. The results of anatomical studies have shown that oil cells occur in all tissues evaluated, and identifying the anatomical differences between them such as, for example, the occurrence of winding abaxial epidermis presenting cells and lack of taste in A. canelilla, morphological similarity between A. rosaeodora and A. parviflora, while the conformation of the root can differentiate between them, since the first tetrarch shows a vascular system while in the second conformation is a conformation triarch. From the morphophysiological data, it was found that the variation in the availability of light the photosynthetic performance of the three species, observing reduced photosynthetic capacity under conditions of lower irradiance. However, the species showed ability to perform morphological and physiological adjustments in response to the different irradiance conditions, suggesting good capacity for acclimatization to the variation in light intensity, which may be due to the emission of leaves longer adequate anatomical and physiological characteristics which allowed increase the efficient use of light, as evidenced by the recovery of amounts of photosynthetic performance indices. As for in vitro establishment of three species of Aniba, the use of sodium hypochlorite at 2% for 30 minutes in aseptic treatment of foliar portions was greater efficiency in reducing microbial contamination and phenolic oxidation. Moreover, foliar portions of plants when cultured in vitro in culture medium supplemented with coconut water or combinations of auxins and cytokinins, showed cell dedifferentiation ability to form callus. Essential oils extracted from the leaves showed differences in the concentrations of constituents assessed the three species studied in response to differences in irradiance in luminance environments. The essential oils showed significant antifungal activity against three important species of pathogenic fungi (Alternaria sp., Fusarium oxysporum and Penicillium chrysogenum). Also, activities were detected trypsin inhibitors and chymotrypsin in protein extracts of rosewood seed (A. rosaeodora). Protein extracts showed high antifungal activity against the tested pathogens (Aspergillus sp., Aspergillus niger, Fusarium oxysporum and Penicillium chrysogenum). Advances in knowledge of the biology of these species may result in addition of new applications, the preservation of species through sustainable exploitation of valuable resources of trees in the Amazon flora.