BACTERIAL ENDOMICROBIOTA OF AGAVE PULQUERO (Agave salmiana). I. ISOLATION, FREQUENCY AND MOLECULAR IDENTIFICATION

Current trends in practicing agriculture point towards the use of microorganisms to influence health, production and quality of crops; previous studies in agave have achieved the isolation of different microorganisms, but the identification of endophytic bacteria is an area that has been little addressed despite its economic importance. In the present study, an analysis of the endomicrobiota present in five types of pulquero agave (Agave salmiana): Manso, Chalqueno, Ayoteco, Pua Larga and Carricillo was carried out. Leaves of these plants were collected in Nanacamilpa de Mariano Arista, Tlaxcala, Mexico and processed for the isolation of endophytic microorganisms in selective media for diazotrophic bacteria, bacilli and fluorescent Pseudomonas. The isolated microorganisms were molecularly identified by the amplification of fragments of the 16S ribosomal subunit. Thirty-five endophytic bacteria were identified from the five types of pulquero agave. The number of isolations obtained corresponded to 7, 11, 3, 5 and 9 from Ayoteco, Carricillo, Chalqueno, Manso and Pua Larga, respectively. The bacterial endomicrobiota of Carricillo was the most diversified (nine species), while Chalqueno presented the lowest bacterial richness (three species); Ayoteco, Manso and Pua Larga presented five unique bacterial species. Overall, the genera with the highest representation in the five types of agave were Bacillus with 12 entries, and Enterobacter and Leclercia with seven entries each. Bacillus subtilis and Leclercia sp. were the species most represented in the agaves as they were found in three of the five types analyzed.