Bacillus subtilis QST 713 Confers Protection to Tomato Plants Against Pseudomonas syringae pv tomato and Induces Plant Defence‐related Genes

Abstract

Bacterial speck, caused by Pseudomonas syringae pv. tomato (Pst), is an economically important disease of tomato, resulting in yield loss of marketable fruit. Management of bacterial speck is a challenge in commercial production fields due to the limited efficacy of current disease management strategies, as the pathogen acquires resistance to antibiotics and fixed copper bactericides and host resistance has not proven durable. Therefore, it is essential to develop alternative disease management strategies, like biological control. In this study, the efficacy of the commercially available biocontrol agent Bacillus subtilis QST 713 along with copper hydroxide was tested against Pst under greenhouse conditions. QST 713 reduced significantly disease severity and incidence compared to control and the copper hydroxide treatment; subsequently, the Pst population was lower in the QST 713‐treated plants compared to control. In parallel, QST 713 and copper hydroxide increased plant height compared to control and mock plants. Furthermore, the quantitative PCR analysis of PR1a, PR1b and Pin2 expression suggests a positive role for Pin2 in the plant protective activity of QST 713, as Pin2 expression was significantly higher in the QST 713‐treated plants challenged with Pst compared to the control Pst‐inoculated plants.

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

“…The progress in pest management strategies using endophytes is an emerging area in plant protection to rationalize the damage caused by plant pathogens in economically important crops. Members of genus Bacillus are considered as potential biological control agents due to their broad-spectrum antagonistic activity against fungi and bacteria, high spore production capacity and resistance to unfavorable conditions (Wulff et al, 2002;Li et al, 2008;Raddadi et al, 2009;Wang et al, 2014;Ferraz et al, 2015;Fousia et al, 2015). In this work, we focused on a Bacillus subtilis CBR05 strain isolated from rice plants that had potent biocontrol activities against the phytopathogenic fungi, F. oxysporum and R. solani (Ji et al, 2014).…”

Bacillus: A Biological Tool for Crop Improvement through Bio-Molecular Changes in Adverse Environments

“…However, the systemic resistance to diseases induced in plants by Bacillus spp. is made possible by increasing SA content and the gene and protein expression of proteinase inhibitor II ( Pin2 ) and pathogen resistant 1 ( PR1 ) (Jiang et al, 2015 ; Fousia et al, 2016 ; Hinarejos et al, 2016 ).…”

Biological control of Pseudomonas syringae pv. aptata on sugar beet with Bacillus pumilus SS-10.7 and Bacillus amyloliquefaciens (SS-12.6 and SS-38.4) strains

“…Fousia et al . () showed that tomato plants treated with the pathogen P. syringae pv. tomato and after that with B. subtilis QST 713 had just 7% disease severity.…”