Screening and systematic resistance induction of endogenous antagonistic growth-promoting bacteria against Camellia oleifera root rot.

LI Li-li; ZENG Guang-yu; WANG Ji-chun; HE Yuan-hao

In order to enrich the biocontrol resources of Camellia oleifera root rot disease and explore its resistance mechanism, antagonistic growth-promoting bacteria were screened from endophytic bacteria of C. oleifera root by plate confrontation method and colorimetric method, and their effects on defense enzyme activities and defense genes of C. oleifera root were measured. The results showed that two strains of efficient endophytic growth promoters AF9 and AH6 were screened from the root system of C. oleifera by combining the antagonistic effect, IAA production, organic phosphorus soluble, inorganic phosphorus production and iron-producing carrier capacity. Both strains were identified as Bacillus. Both of them could increase the root defense enzyme activities, and the activities of superoxide dismutase (SOD), phenylalanine ammoniase (PAL), polyphenol oxidase (PPO), and peroxidase (POD) reached the peak at 8 h, 10 h,12 h, and 24 h, respectively. PAL, RBOHC and POD, genes were highly expressed at 10 h, 12 h, and 24 h, respectively, while no significant expression was found in control group. The results indicated that the antagonistic growth promoting bacteria AF9 and AH6 could induce systemic resistance of C. oleifera, which laid the foundation for the development of later bacteriotics and biological control of C. oleifera root rot.

ENDOPHYTIC bacteria; CAMELLIA oleifera; POLYPHENOL oxidase; SUPEROXIDE dismutase; BACILLUS (Bacteria); ROOT rots

Chinese Journal of Oil Crop Sciences, 2024, Vol 46, Issue 6, p1390

1007-9084

Academic Journal

10.19802/j.issn.1007-9084.2023115