Microbial Consortia for Effective Biocontrol of Root and Foliar Diseases in Tomato

Abstract

The use of beneficial microorganisms for the biological control of plant diseases and pests has emerged as a viable alternative to chemical pesticides in agriculture. Traditionally, microbe-based biocontrol strategies for crop protection relied on the application of single microorganisms. However, the design of microbial consortia for improving the reliability of current biological control practices is now a major trend in biotechnology, and it is already being exploited commercially in the context of sustainable agriculture. In the present study, exploiting the microbial library of the biocontrol company Koppert Biological Systems, we designed microbial consortia composed of carefully selected, well-characterized beneficial bacteria and fungi displaying diverse biocontrol modes of action. We compared their ability to control shoot and root pathogens when applied separately or in combination as microbial consortia, and across different application strategies that imply direct microbial antagonism or induced systemic plant resistance. We hypothesized that consortia will be more versatile than the single strains, displaying an extended functionality, as they will be able to control a wider range of plant diseases through diverse mechanisms and application methods. Our results confirmed our hypothesis, revealing that while different individual microorganisms were the most effective in controlling the root pathogen Fusarium oxysporum or the foliar pathogen Botrytis cinerea in tomato, the consortia showed an extended functionality, effectively controlling both pathogens under any of the application schemes, always reaching the same protection levels as the best performing single strains. Our findings illustrate the potential of microbial consortia, composed of carefully selected and compatible beneficial microorganisms, including bacteria and fungi, for the development of stable and versatile biological control products for plant protection against a wider range of diseases.

Designing a synthetic microbial community devoted to biological control: The case study of Fusarium wilt of banana

“…(Smith, 2011;Johns et al, 2016;de Souza et al, 2020). The literature agrees that microbial consortia outperform formulations based on single strains, both for biotechnological tasks (Faust, 2019;Mauri et al, 2020;Sgobba and Wendisch, 2020) and biocontrol (Whipps, 2001;Thakkar and Saraf, 2015;Bradáčová et al, 2019;Minchev et al, 2021). One of the few examples of microbial consortia used against FWB was the combination of two endophytes, B. subtilis EPB56 and EPB10, and the rhizobacterium P. fluorescens Pf1, which gave 78% disease reduction (Kavino and Manoranjitham, 2018).…”

Epiphytic Yeasts and Bacteria as Candidate Biocontrol Agents of Green and Blue Molds of Citrus Fruits

“…This case was exemplified well by the bacterial isolate S15 of B. amyloliquefaciens , which performed better at a low temperature (4 °C), while its efficacy was significantly impaired at room temperature. This inconvenience may be circumvented by the use of broad-spectrum consortia of BCAs with complementary modes of action [ 135 ].…”

Advances and Perspectives in the Use of Biocontrol Agents against Fungal Plant Diseases

“…To circumvent these problems and increase the stability and efficiency of useful microorganisms introduced in the soil and rhizosphere, solutions based on combinations of BCAs, commonly called microbial consortia, consisting of two or more microbial strains, have been developed [52]. Recently, the design of microbial consortia is a major trend in biotechnology applied to the management of soil-borne diseases, and microbial communities consisting of separate application of prokaryotes [54,55] or fungi [56] or use of a mix of fungi and bacteria [57][58][59] are already available. Besides the natural microbiome, the application of selected mixtures of microorganisms has proven to be effective in biocontrol experiments [60,61].…”