Elucidating desiccation tolerance and implementing anhydrobiotic engineering and encapsulation strategies to increase storage stability of microbial control agents

• Grant number: 21/13594-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: June 01, 2023
• End date: June 09, 2026
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Italo Delalibera Júnior
• Grantee: Natasha Sant Anna Iwanicki
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated scholarship(s): 24/01614-7 - Anhydrobiotic engineering and encapsulation strategies to increase storage stability of microbial control agents, BE.EP.PD

Abstract

The genus Metarhizium (Hypocreales: Clavicipitaceae), an important group ofen to mopathogenic fungi, can grow in liquid medium as blastospores, yeast-like cells, that are infective to several pests in agriculture. Pantoea agglomerans is a gram-negative nonsporulating bacteria with a highly versatile lifestyle and great potential for use as a plant growth-promoting rhizobacteria (PGPR) and biocontrol agent for pathogens and nematodes. Limitations related to low desiccation tolerance and short-term storage stability have limited the commercial use of P. agglomerans and Metarhizium blastospores. Considering that preservation of blastospores and non-spore-forming bacteria by desiccation is the preferred method in formulations for long-term storage, approaches to understand and overcome challenges associated with low desiccation tolerance and short storage stability are necessary. In this research, we propose to profoundly investigate the mechanisms associated with desiccation tolerance of blastospores and non-spore-forming bacteria and ways to overcome them. We will use multidisciplinary approaches, including biochemical analyses, preconditioning process, high-performance liquid chromatography, flow cytometry, metabolome profile analyses, and encapsulation strategies to create new technologies. With the development of part of the project in Germany (BEPE-FAPESP period), part at USP-ESALQ and USP-FMRP with the participation of Prof. Patel and Dr. Dèsirèe, Prof. Delalibera, Prof. Braga, respectively, this project will provide a fundamental understanding of strategies for handling the culture medium and culture conditions for greater dissection tolerance and longer storage stability of blastospores of entomopathogenic fungi and non-sporulating bacterium P. agglomerans. Additionally, this research will be the first to deeply explore biochemical and physiological mechanisms associated with low storage stability in entomopathogenic fungi blastospores and P. agglomerans which might apply to other fungal and bacterial cells with similar characteristics. (AU)