Diversity and function of culturable actinobacteria in the root-associated of Salvia miltiorrhiza Bunge

Abstract

The root-associated actinobacteria play important roles in plant growth, nutrient use, and disease resistance due to their functional diversity. Salvia miltiorrhiza is a critical medicinal plant in China. The root actinobacterial community structure has been studied; however, the functions of root-associated actinobacteria of S. miltiorrhiza have not been elucidated. This study aimed to decipher the diversity and function of the culturable root-associated actinobacteria in plant growth using culture-dependent technology and culturable microbe metagenomes. We isolated 369 strains from the root-associated actinobacteria, belonging to four genera, among which Streptomyces was dominant. Besides, the functional prediction revealed some pathways related to plant growth, nitrogen and phosphorus metabolism, and antagonistic pathogens. We systematically described the diversity and functions of the culturable root-associated actinobacteria community. Our results demonstrated that the culturable root-associated actinobacteria of S. miltiorrhiza have rich functionalities, explaining the possible contribution of culturable root-associated actinobacteria to S. miltiorrhiza’s growth and development. This study provides new insights into understanding the function of the culturable root-associated actinobacteria and can be used as a knowledge base for plant growth promoters and biological control agent development in agriculture.

Potentiality of actinobacteria to combat against biotic and abiotic stresses in tea [Camellia sinensis (L) O. Kuntze]

“…Several studies on the inhibitory effect of actinobacteria have been related to the production of fungal cell wall degrading enzyme, chitinase (Kamil et al, 2018; Veliz et al, 2017). Actinobacteria are also extensively documented as a producer of another lytic enzyme, β‐glucanolytic enzymes (β‐1,3‐glucanase) that inhibit many PPF (Edison & Pradeep, 2020; Wu et al, 2021).…”

“…Furthermore, genome analysis revealed the presence of genes involved in the biosynthesis of EPS, glycine‐betaine synthesis and transport gene ( betABP ) associated with salt tolerance. Additionally, Wu et al (2021) reported several genes involved in nitrogen metabolism and phosphorus metabolism ( nifU , narG , narI , nirB , nirD , nirK , nxrB , norB , glnA , GLUL, gltB , gltD , nxrA and gdhA , phoD , phnG , phnI , phnJ and phnA ) and siderophore biosynthesis ( pchB , dhbF and entF ). Cruz‐Morales et al (2017) proposed a novel des gene, termed as desG , found to be associated with phenylacetyl incorporation during biosynthesis of siderophores in actinobacteria.…”

Biological control and plant growth promotion properties of Streptomyces albidoflavus St-220 isolated from Salvia miltiorrhiza rhizosphere

“…In addition, they are able to survive in harsh environments and colonize the root of plants belonging to multiple species including Sa. miltiorrhiza ( Suárez-Moreno et al, 2019 ; Jose et al, 2021 ; Wu et al, 2021 ). Moreover, Streptomyces strains have multiple strategies to suppress fungal pathogens such like nutrients competition, cell wall degradation, virulence factors degradation and plant immunity induction ( Chen et al, 2018 ).…”