ISOLATION AND IDENTIFICATION OF MYCOBIOTA FROM SOILS DEDICATED TO TOMATO CULTIVATION IN AZUERO

Abstract

Antagonist fungi represent an ecological alternative to the use of agrochemicals to control phytopathogenic microorganisms that affect crops. This work was carried out during 2016 and 2017 with the purpose of finding fungi of the genus Trichoderma and knowing the diversity of fungi present in soils dedicated to the cultivation of tomatoes (Solanum lycopersicum). Eight study sites located in the Azuero Peninsula were selected. In total, 200 soil samples were collected (25 per site) and serial dilutions were carried out for isolation. Thus, a total of 590 fungi were isolated, thus generating around 576 inclined fungi (morphotypes). The identification was carried out at the genus level, and at the morphospecies, for fungi that only produced vegetative structure. The data were statistically analyzed using Pearson's correlation coefficient. On the other hand, 340 fungal growths were isolated in small Petri dishes, grouped into 15 genera. 75% of the isolates were identified at the gender level; 2% were yeasts; 23% were sterile mycelium. The most frequent genera were: Aspergillus and Penicillium. In addition, biochemical tests of microbial respiration and enzymatic activity of dehydrogenase were carried out in the soils of the four farms of greatest agricultural importance, where it was determined that the soil that presented the highest microbial activity xi (CO₂ production) was that of La Colorada, followed by El Faldar and Tonosí; the one that presented the lowest microbial activity was Tonosí Centro. With the calculation of the CFU it was possible to determine that the optimal fungal load is found in the 10^-4 dilution.