Metabolomics studies to elucidate the biochemistry underlying the effects of biostimulants on maize
Metabolomics studies to elucidate the biochemistry underlying the effects of biostimulants on maize by Ms. Lerato Nephali
Bio: Ms. Lerato Nephali is a doctoral candidate in the Department of Biochemistry at the University of Johannesburg (UJ) under the supervision of Dr. Fidele Tugizimana. Ms Nephali obtained a BSc in Biochemistry and Psychology in 2016 and BSc Honours (Biochemistry), MSc (Biochemistry) at UJ in 2017 and 2020, respectively. Her PhD project is a metabolomics application to elucidate modes of action of plant biostimulants. Her current research focus, and interests include metabolomics, computational metabolomics, metabolite annotation, biochemical and molecular mechanisms underlying biostimulant-plant interactions. Ms. Nephali is an author/co-author of several metabolomics papers (from both her MSc and PhD work) in leading peer-reviewed international scientific journals.
Abstract: Metabolomics studies to elucidate the biochemistry underlying the effects of biostimulants on maize
Microbial biostimulants have emerged as effective and sustainable strategies to improve agricultural productivity; however, the modes of action of such formulations are still enigmatic. This hampers industries and farmers from confidently and innovatively exploring, formulating and fully implementing the use of microbial biostimulants into agronomic practices for sustainable agriculture and food production. Thus, in this work, mass spectrometry-based metabolomics and molecular networking (MN) were applied to (i) interrogate the intracellular metabolome of microbial biostimulants (Bacillus isolates and the consortium) and (ii) to elucidate metabolic changes in the rhizosphere and leaves of maize plants treated with the microbial biostimulants. The results revealed that the metabolome of the microbial biostimulants is characterised by various molecular families such as lipids and lipid-like molecules, benzenoids, organic oxygen compounds, organic acids and derivatives. Lipopeptides involved in the plant-microbe intercommunication, were found to be key discriminating metabolites in the intracellular metabolome of the microbial biostimulants. The rhizosphere metabolomics showed that the microbe-plant interactions are facilitated by a complex and dynamic chemical communication involving differential changes in various (rhizo-) metabolites such as benzoxazinoids. Furthermore, maize plants treated with the microbial biostimulants showed a reprogrammed metabolism involving alterations in various classes of metabolites involved in both plant growth and priming events. Such metabolic insights contribute to ongoing efforts to generate actionable knowledge for the biostimulant industry and the agricultural sector for sustainable global food security.