Isolation and characterization of endophytic bacterial community from potato (

Plant microbiota plays a crucial role in the growth, development, and health of their hosts. Understanding the plant–microbe interactions support strategies to improve the productivity and quality of crops. This study aimed to analyze the cultured endophytic bacteria from seed potato of five varieties. The morphological diversity of isolates was assessed using the following parameters: color, form, surface, appearance, size of the colony, cell shape, Gram reaction, endospore formation. The identification of the endophytic bacteria was carried out using MALDI-TOF mass-spectrometry method. A total of 49 endophytic isolates were first found in leaves, stems, roots and tubers of potato cultivars Reggi, Sprint, Gala, Red Sonia, and Picasso at the flowering stage. It was shown that the majority of endophytic bacteria (59%) belonged to the genera Bacillus. Functional diversity was screened for the ability to produce the phytohormone indole-3-acetic acid (IAA) and antagonistic potential against Fusarium oxysporum. The application of cluster analysis methods to the morphological and functional characteristics of 49 endophytic isolates allowed for a clear demonstration of the diversity of endophytic bacteria in the different potato varieties studied. The most interesting cluster was found to be cluster 2, which contains the isolates Bacillus toyonensis R SE L 22 and Enterobacter ludwigii R S R 3 obtained from the leaves and roots of cultivar Reggi. These isolates showed the highest IAA production, inhibited the growth of strain F. oxysporum DR57 by 62.2% and 50.3%, respectively, and can be considered as promising growth-promoting endophytic bacteria.