Estudo do potencial de controle biológico de fungos endofíticos associados ao babaçu

Abstract

Based on the potential for new discoveries from the exploration of secondary metabolism of endophytic fungi and the scarce studies of the microbiota of Attalea speciosa (babassu), the present work aimed to prospect endophytic fungi of this species, as well as to evaluate the biotechnological potential of fungal isolates through antagonism tests. The babassu samples, fruit in different stages of maturation and leaf, were collected at Campus II of Unifesspa, submitted to a sterilization process and inoculated in batata dextrose agar (BDA) culture medium for the prospection and isolation of fungal colonies. DNA extraction using the chloroform:isoamyl alcohol extraction protocol was performed to identify the endophytes. The gene material of the isolates was amplified, from which six were sequenced. To evaluate the antagonistic potential of the endophytes, each isolate was confronted with the phytopathogens Colletotrichum (C2) and Lasiodiplodia pontae (L18). Competition between the microorganisms was evaluated with daily measurements of the growth of the paired fungi and data analysis was performed by Excel and Paleontological Statistics (PAST) program. From the prospecting procedures 12 endophytic fungi were isolated, of which six were identified as Curvularia luneta (AMP), Daldinia eschscholtzii (FB2M), Curvularia aerialis (FB1V), Xilaria feejeensis (F1), Fusarium solani (FB3V) and Hipoxylon anthochroum (CA1M). From the evaluation of antagonism tests it was possible to highlight a promising inhibitory activity (65, 75% and 62.37%) associated with the endophytic D. eschscholtzii (FB2M) against both phytopathogens, L. pontae (L18) and Colletotricum sp (C2), in this order. Metabolic profiling studies from extracts obtained from the paired cultures led to hypotheses that the observed inhibition is due to a physical barrier or associated with the primary metabolism of the endophyte. Although preliminary, the results obtained are promising and motivate the continuity of the research, since this is the first record of the profile of endophytic fungi associated with babassu, as well as preliminary notions of the biotechnological potential of these isolates.