Research Advances of Beneficial Microbiota Associated with Crop Plants

Abstract

Plants are associated with hundreds of thousands of microbes that are present outside on the surfaces or colonizing inside plant organs, such as leaves and roots. Plant-associated microbiota plays a vital role in regulating various biological processes and affects a wide range of traits involved in plant growth and development, as well as plant responses to adverse environmental conditions. An increasing number of studies have illustrated the important role of microbiota in crop plant growth and environmental stress resistance, which overall assists agricultural sustainability. Beneficial bacteria and fungi have been isolated and applied, which show potential applications in the improvement of agricultural technologies, as well as plant growth promotion and stress resistance, which all lead to enhanced crop yields. The symbioses of arbuscular mycorrhizal fungi, rhizobia and Frankia species with their host plants have been intensively studied to provide mechanistic insights into the mutual beneficial relationship of plant–microbe interactions. With the advances in second generation sequencing and omic technologies, a number of important mechanisms underlying plant–microbe interactions have been unraveled. However, the associations of microbes with their host plants are more complicated than expected, and many questions remain without proper answers. These include the influence of microbiota on the allelochemical effect caused by one plant upon another via the production of chemical compounds, or how the monoculture of crops influences their rhizosphere microbial community and diversity, which in turn affects the crop growth and responses to environmental stresses. In this review, first, we systematically illustrate the impacts of beneficial microbiota, particularly beneficial bacteria and fungi on crop plant growth and development and, then, discuss the correlations between the beneficial microbiota and their host plants. Finally, we provide some perspectives for future studies on plant–microbe interactions.

Diversity and Structure of the Endophytic Bacterial Communities Associated With Three Terrestrial Orchid Species as Revealed by 16S rRNA Gene Metabarcoding

“…Bacteria and fungi, the dominant components of the plant microbiota, can deeply influence plant growth and responses to stresses. For these reasons, several studies in the last decade focused on the structure and functions of the plant microbiota, with the aim to link them to plant fitness and crop productivity ( Bulgarelli et al, 2013 ; Compant et al, 2019 ; Tian et al, 2020 ).…”

Comparison between wild and related cultivated rice species reveals strong impacts of crop domestication on methane metabolism of the rhizomicrobiome

“…Generally, it can be presumed that wild plant species have characteristics that support the plants to survive under adverse natural conditions, including environmental stresses like drought, extreme temperatures, low-nutrient soils and the presence of soil-borne pathogens [17][18][19]. This higher acclimatization ability of wild species may be attributed to their associations with the microbial communities in the rhizosphere among many others [19][20][21].…”

Wild rice controls more root endophytic fungi than cultivated rice in the F1 offsprings after the crossbreeding

“…Endophytic microbes inhabit plant tissues without causing any obvious damage to their host, and play crucial roles in plant growth, development, tness and protection (Farrar et al 2014;Truyens et al 2015;Tian et al 2020b). These endophytic microbes, including bacteria and fungi, spend a portion of their life cycle inside plants, normally residing on intercellular spaces and gaining carbohydrates, amino acids and inorganic nutrients from plants (Bacon and Hinton 2006).…”

“…Rice (Oryza sativa) is the main food staple for approximately half of the world's population; and thus, breeding for yield improvement to feed an ever-increasing world population is a critical goal for the rice research community (Zhang et Tian et al 2020b). Hybridization of cultivated plant species with wild species can transfer bene cial traits from both parents to the next generation, and may induce bene cial changes in the community composition of the endophytic microbiomes associated with the offspring to help them produce higher yields even under adverse environmental conditions (Goulet et al 2017; Cao 2018).…”