Induction of defence-related enzymes in tomato (Solanum lycopersicum) plants treated with Bacillus subtilis CBR05 against Xanthomonas campestris pv. vesicatoria

Abstract

Induction of defense-related enzymes in tomato (Solanum lycopersicum) plants treatedwith Bacillus subtilis CBR05 against Xanthomonas campestris pv. vesicatoria Running Head: B. subtilis CBR05 induced defense-related enzymes in tomato ABSTRACT Bacterial spot disease, caused by Xanthomonas campestris pv. vesicatoria is one of the most important destructive diseases of tomato in many parts of the agricultural world. Bacillus sp.has been reported to be significantly reducing the incidence of disease in the diversity of hosts. The present study aims to determine the effects of Bacillus subtilis CBR05 inoculation on bacterial spot disease severity and the induction of defense-related enzymes response in tomato. Tomato leaves were evaluated to determine the activities of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and polyphenol oxidase (PPO)) and the content of malondialdehyde (MDA). A reduction in bacterial spot severity was observed in plants inoculated with B. subtilis, compared those of uninoculated controls. A significant increase in SOD, CAT, POD, and PPO activities was observed in plants treated with B. subtilis after 24 h inoculation compared with non-inoculated pathogen control and mock-inoculated controls. During 72 h after inoculation, B. subtilis inoculated plants resulted in significant increase of SOD, POD and PPO activities comparing to non-inoculated pathogen control. We also observed that low levels of natural SOD, CAT, POD, and PPO activities in the mock-inoculated control. Moreover, MDA content was induced by pathogen infection, and its amount in B. subtilis inoculated plants was significantly lower than in pathogen control. Our results suggest that early increases in antioxidant enzymes and the reduction in MDA content with B. subtilis inoculation may play a pivotal role in mitigating oxidative stress thereby induced systemic resistance against bacterial spot disease in tomato.

Bacillus subtilis CBR05 for Tomato (Solanum lycopersicum) Fruits in South Korea as a Novel Plant Probiotic Bacterium (PPB): Implications from Total Phenolics, Flavonoids, and Carotenoids Content for Fruit Quality

“…Similarly, increases in total flavonoids content by B. licheniformis have been reported for tomato fruits [32]. In our previous studies, we also found that B. subtilis CBR05 inoculation enhanced the accumulation of peroxidase and polyphenol oxidase enzymes, which are involved in the metabolism of phenols and flavonoids [22,23]. Hence, this shows that B. subtilis colonization induces resistance against biotic and abiotic stress agents.…”

“…The use of PGPR is increasing in agriculture and may offer an attractive alternative to synthetic chemicals and fertilizers. Plant growth-promoting microorganisms are efficient microbial competitors that can promote plant growth by producing phytohormones and/or by increasing available nutrients through production of secondary metabolites or act as biocontrol agents to protect plants from infection by phytopathogens [19,[21][22][23][24]. There have been many reports on PGPR and their effective roles [19][20][21][22][23][24].…”

“…Among various PGPR approaches, Bacillus species are considered as likely candidates due to their broad-spectrum antagonistic activity against phytopathogens, production of long-lived and stress-tolerant spores, secondary metabolites, lytic enzymes, resistance to adverse environments, and plant growth promotion [19,[21][22][23]. Bacillus subtilis plays a significant role in improving plant growth and tolerance to both biotic and abiotic stresses.…”

Induction of Systemic Resistance in Cucumber by Hypovirulent Binucleate Rhizoctonia Against Anthracnose Caused by Colletotrichum orbiculare

“…Increased peroxidase activity is also well observed in rhizobacteria-induced systemic resistance. Chandrasekaran and Chun (2016) demonstrated that treating tomato plants with Bacillus subtilis CBR05 significantly enhanced the activities of antioxidant enzymes including peroxidase. Yanti (2015) reported that rhizobacteria enhanced peroxidase enzyme activity.…”

Bacterial Endophytes: The Hidden Actor in Plant Immune Responses Against Biotic Stress

“…A numerous study indicated that ISR can be trigged through several compounds produced by endophytes such as phytohormones, lipopeptides, pyocyanin, siderophore, and VOCs [135][136][137][138]. ISR triggered by endophytic bacteria can protect the host against a wide range of pathogens including soilborne pathogenic fungi [139][140][141], biotrophic pathogens [142,143], viruses [144][145][146], nematodes [147], and insect herbivores [148,149].…”