New approaches for biological control of plant pathogens

Sunflower field with blooming sunflowers.

Beneficial microorganisms present a promising alternative to conventional plant protection and could replace chemical pesticides in the near future. Plant pathogens are responsible for various devastating plant diseases and lead to huge yield losses caused by pre- and postharvest spoilage.

It is estimated that around 30% of the global crop production is lost due to plant pathogens and microbial contaminations. Beneficial microorganisms, which can either actively outcompete such pathogens and/or deplete resources required for their growth, are known as BioControl Agents (BCAs). These microorganisms often provide additional advantages when sprayed on crops or encapsuled with plant seeds (acib partner Biotenzz). Such advantages include a higher resistance to drought and salt stress, higher germinations rates, plant growth promotion, and provision of specific nutrients. Researchers at acib are exploring the applicability of microbial communities for the reduction of biotic and abiotic stresses. In contrast to single BCAs, which often show inconsistent activity under field conditions, mixtures of different microorganisms are more likely to be able to deliver the desired effects in large-scale applications. Christin Zachow, a senior scientist at ACIB, and her team are currently exploring the potential of mixed bacterial communities towards economically important crop plants.

Christin Zachow is convinced that, “Microbiome-based strategies to improve plant health, growth and nutrition are the future of biocontrol. By applying target-specific microbial composition and particular helper strains emerging pathogens can be suppressed and abiotic stresses reduced. Moreover, tools with a bioinformatics background will unravel the plant microbiome structure and function. The resulting knowledge will provide individual solutions for agricultural tasks.”

So far it was demonstrated that specifically designed communities can enhance the persistence of maize, sorghum, and oilseed rape. Plants treated with these communities showed a significantly better response to biotic and abiotic stress than control groups treated with single BCAs. Future projects within acib will focus on the identification of stabilizing elements for mixed communities and novel mechanisms for efficient field application.

This blog bases on a presentation presented at the DPG Working Group Biological Control of Plat Diseases in March 2016: 
C.M. Laireiter, G. Berg and C. Zachow: Bacterial consortia against biotic and abiotic stresses  
Picture credits: Pixabay