Isolation and identification of endophytic actinobacteria from Iris persica and Echium amoenum plants and investigation of their effects on germination and growth of wheat plant

Abstract

Plant biotechnology helps to develop different types of new products with increased resistance to disease, greater tolerance to drought and salt stress, and better nutritional value. The interaction of plants and microorganisms will play a significant role to achieve this purpose. The aims of this study were to isolate endophyte Actinobacteria strains of some medicinal plants and the investigation of their bioactive potential. 15 Actinobacteria strains were selectively isolated from Persian iris and Echium amoenum plants, and then their belonging to Actinobacteria phylum was confirmed using an Actinobacteria‐specific primer pair. The antioxidant activity of the crude extract obtained from the isolated strains was investigated based on DPPH method. Investigating the antioxidant activity of the crude extract showed that at a concentration of 100 μg/mL, the two strains EG1 and EG2 had 71% and 78% antioxidant activity, respectively. According to the phylogeny studies, it was determined that two strains belonged to the Streptomyces genus. The effect of supernatant achieved from selected endophytic strain on 35‐day wheat plants showed that the supernatant considerably promotes root and shoot growth and chlorophyll content under salinity stress (150 mM NaCl). In general, it can be concluded strains that live symbiotically with medicinal plants are rich sources of bioactive compounds. Therefore, identification of the bioactive compounds in the extract of isolated Actinobacteria from medicinal plants and further studies on their metabolism are suggested.

Deciphering the mechanisms, hormonal signaling, and potential applications of endophytic microbes to mediate stress tolerance in medicinal plants

“…(2023) reported that Bacillus strains NBRI HYL5, NBRIHYL8, and NBRIHYL9 with ACC deaminase activity, biofilm, phosphate solubilization, exo-polysaccharide and alginate generation properties enhanced abiotic stress tolerance in Gloriosa superb . Endophytic microbes, Streptomyces umbrinus EG1 and S. carpaticus EG2 promote root-shoot growth and chlorophyll content, thereby enhancing salt tolerance in Iris persica and Echium amoenum plants ( Oloumi et al., 2023 ).…”