Plant Microbiome: Origin, Composition, and Functions

Abstract

Microorganisms play an important role in the growth and development of a plant throughout its entire life cycle. Recent advances in the methods of molecular biological analysis have expanded our understanding of the composition and functions of plant microbiota (epiphytic, rhizosphere, and endosphere) and the molecular mechanisms associated with specific processes that govern plant-microorganism interactions. This article reviews the types of plant microbial communities, their sources of origin, and species composition, as well as the critical role they play in modulating the plant immune response against phytopathogens, improving the elemental nutrition of plants, scaring away herbivorous animals, producing phytohormones, and enabling plants to thrive under extreme environmental conditions.

Influence of the Antibiotic Oxytetracycline on the Morphometric Characteristics and Endophytic Bacterial Community of Lettuce (Lactuca sativa L.)

“…The number of OTUs in the soil of the control variant was higher than that in the water of the control variant of the hydroponic experiment. However, in leaves and roots, the number of OTUs was similar for both soil and hydroponic experiments since the endophytic bacterial community of plants is determined mainly by the composition of the seed bacterial community [35]. It was found that the greatest diversity of the bacterial community was in the soil samples, and the least was in the samples of the leaves and roots of lettuce.…”

“…As a result, the endophytic community of an adult plant consists of the species present in the seed and the species present in the substrate. A small proportion of the community is also occupied by accidentally penetrating species (for example, from the air through damage in plant cells) [32,35].…”

“…It was found that, in the control samples, the dominant species in different parts of the lettuce were similar regardless of the method of cultivation, whether in hydroponics or in soil. Indeed, it has been shown that the main number of microorganisms is formed in plant organs from the seed, and a smaller number is introduced from the environment [35]. In the presence of OTC, changes in the number of dominant bacteria were found.…”

Glutamic-N,N-Diacetic Acid as an Innovative Chelating Agent in Microfertilizer Development: Biodegradability, Lettuce Growth Promotion, and Impact on Endospheric Bacterial Communities

“…According to modern understanding, microorganisms residing within plants play an equally significant role as the plant's own tissues and organs. Indeed, the endophytic microbiome plays a crucial role in promoting plant growth (PGP) and combating phytopathogens [44,45]. Endophytes can directly influence plant growth by producing phytohormones (e.g., jasmonic and salicylic acids) and inhibit the production of plant cells' ethylene.…”