Biochemical Profile and Antifungal Activity of Endophytic Bacteria From Roots of Piper nigrum L. (Piperaceae) Against Phytopathogenic Fungi

Beneficial endophytic bacteria may confer advantages to their host plants and to the environment by pathogen control, while reducing pesticide use. The aim of this work was to determine the biochemical profile and antifungal activity of endophytic bacteria from black pepper roots against Fusarium solani f. sp. piperis , F. oxysporum , and Colletotrichum gloeosporioides , which cause fusariosis and anthracnose in black pepper. One hundred and sixty‐four endophyte bacteria strains isolated from black pepper roots were tested in vitro against three phytopathogenic fungi. Seven selected antagonistic strains were identified at the genus level by sequencing the 16S region of the ribosomal RNA. In addition, the production of lytic enzymes and siderophores was evaluated that may be related to the biocontrol of pathogenic microorganisms. The effect of ethyl acetate and ethanolic extracts of antagonistic strains on the germination of pathogen spores was evaluated. Strains C5.4, C5.9, T1.5, T4.1, T4.7, T6.2, and T6.4 showed antifungal activity with inhibition ranging from 30.27% to 61.42%, and were identified as species of the genus Burkholderia . The biochemical profile showed that strains produced lipase, esterase, protease, and siderophores, which may be related to their antifungal activity. The best results of antifungal activity were shown by the ethyl acetate extracts of strains C5.4, C5.9, T4.7, T6.2, T6.4, and T4.1, with percentages ranging from 4.71% to 51.89%. This study demonstrated that endophytic bacteria from black pepper have potential for the biocontrol of fungal diseases and can be further investigated to obtain a formulation for the control of pathogenic microorganisms associated with this crop.