Titania (TiO2) nanoparticles enhance the performance of growth-promoting rhizobacteria

Abstract

A novel use of nanotitania (TNs) as agents in the nanointerface interaction between plants and colonization of growth promoting rhizobacteria (PGPR) is presented. The effectiveness of PGPRs is related to the effectiveness of the technology used for their formulation. TNs produced by the Captigel patented SolGel approach, characterized by the transmission and scanning electron microscopy were used for formulation of the harsh environment PGPR strains. Changes in the biomass of wheat seedlings and in the density of single and double inoculants with and without TNs were monitored during two weeks of stress induced by drought salt and by the pathogen Fusarium culmorum. We show that double inoculants with TNs can attach stably to plant roots. Regression analysis indicates that there is a positive interaction between seedling biomass and TN-treated second inoculant colonization. We conclude that TN treatment provides an effectual platform for PGPR rational application via design of root microbial community. Our studies illustrate the importance of considering natural soil nanoparticles for PGPR application and thereby may explain the generally observed inconsistent behavior of PGPRs in the field. These new advancements importantly contribute towards solving food security issues in changing climates. The model systems established here provide a basis for new PGPR nanomaterials research.

Fighting Fusarium Pathogens in the Era of Climate Change: A Conceptual Approach

“…can survive several years on plant debris, even if located deep in the soil, the pathogens themselves, however, develop only on the upper parts of living plants [20]. Hence, the review focuses on the phyllosphere, which has a large potential for the design of beneficial microbial biofilm layers [52,53].…”

“…The aim of such a map is to find an optimum strategy to maximize the isolate's expected positive effect and minimizing the time it takes. Adapted from Bacillus thuringiensis AZP2 metabolic system [53].…”

“…For example, a change in a process that has a small effect on several biofilm components might not have a detectable effect on any single biofilm component. Strategies to avoid such biases depend on techniques where appropriate pools of genotypes or phenotypes are formed and by that boost the signal-to-noise ratio to allow effective detection of multiple component, which can ultimately improve the detection of the remaining signal for each component [53,77].…”

The plant microbiome as a resource to increase crop productivity and soil resilience: A systems approach

“…Plant growth-promoting rhizobacteria The soil surrounding plant roots is one of the main sources of plant growth promoting rhizobacteria (PGPR) that have metabolic capabilities for growth promotion and protection of different crops from abiotic and biotic stress (Timmusk 2013;Timmusk, El Daim et al 2014;Timmusk, Kim et al 2015;Timmusk, Seisenbaeva et al 2018). The very first report on enhancement of plant drought stress tolerance by rhizosphere bacteria was published in 1999 (Timmusk and Wagner 1999).…”

“…This enhances bacterial attachment to the root and plant biomass ( Fig. 1) (Palmqvist, Bejai et al 2015;Timmusk, Seisenbaeva et al 2018). In order to be able to reveal the mechanism of action and monitor the fate performance of the strains, strategies for the strains genetic manipulation have been developed and genomes sequenced (Kim and Timmusk 2013).…”