Enhanced root uptake of acibenzolar-S-methyl (ASM) by tomato plants inoculated with selected Bacillus plant growth-promoting rhizobacteria (PGPR)

• Published in: Applied soil ecology : a section of Agriculture, ecosystems & environment ecosystems & environment, 2014-05, Vol.77, p.26-33
• Main Authors: Myresiotis, Charalampos K., Vryzas, Zisis, Papadopoulou-Mourkidou, Euphemia
• Format: Article
• Language: English
• Subjects: Acibenzolar-S-methyl (ASM); Agronomy. Soil science and plant productions; Bacillus; Biochemistry and biology; Biological and medical sciences; CGA 210007; Chemical, physicochemical, biochemical and biological properties; Fundamental and applied biological sciences. Psychology; Lycopersicon esculentum; Microbiology; Physics, chemistry, biochemistry and biology of agricultural and forest soils; plant growth-promoting rhizobacteria (PGPR); Pumilus; Soil science; tomato; uptake
• ISSN: 0929-1393; 1873-0272
• DOI: 10.1016/j.apsoil.2014.01.005

•Dissipation rate of acibenzolar-S-methyl (ASM) in rhizosphere soil is not affected by plant growth-promoting rhizobacteria (PGPR) inocula.•Rapid formation of the major metabolite CGA 210007 in the rhizosphere.•Maximum concentrations in aerial parts were observed 48–96 h after application.•Bacillus subtilis GB03 and Bacillus pumilus SE34 stimulate the systemic translocation.•Higher colonization of PGPR in the roots compared to the rhizosphere soil. The combination of plant growth-promoting rhizobacteria (PGPR) and plant resistance inducers is an alternative crop protection approach in modern agricultural systems. Despite the numerous reports regarding the improved suppression of plant pathogens by their combined application, little is known about the interactions among these components. In the present study, the persistence behavior of the plant activator acibenzolar-S-methyl (ASM) in the rhizosphere of tomato plants and its root uptake as well as systemic translocation ability in aboveground parts after combined use with certain Bacillus PGPR strains (B. amyloliquefaciens IN937a, B. pumilus SE34, B. subtilis FZB24 and GB03) were investigated. Additionally, the population dynamics of the PGPR strain B. subtilis GB03 at the tomato root system and rhizosphere soil applied with or without the pesticide were studied. The results showed that the addition of PGPR inocula did not affect the dissipation rate of ASM in rhizosphere soil. Also, the formation of its major metabolite CGA 210007 in soil was rapid, since it was detected one hour after root drench and it was maintained at high levels during the sampling period without considerable variations among the bacterial treatments compared to the control. The uptake and systemic translocation of ASM and its metabolite CGA 210007 from root to shoot was rapid and maximum concentrations were observed at 48–96 h after its application. It was revealed that in plants treated with the PGPR strains B. subtilis GB03 and B. pumilus SE34 the uptake and systemic translocation of ASM and CGA 210007 in the aerial parts of the tomato plants was significantly higher compared to the control receiving no bacterial treatment. Also, the populations of the strain B. subtilis GB03 showed high colonizing ability in the root system and the rhizosphere soil. PGPR strains that lead to enhanced pesticide uptake by plants should be further evaluated as components in integrated management systems.