PLANT-SOIL-MICROORGANISM INTERACTIONS UNDER THE USE OF ROCK POWDER: A MULTI-OMIC APPROACH

Abstract

Brazilian agriculture, heavily reliant on synthetic potassium-rich fertilizers, faces significant environmental challenges. In this scenario, remineralizers such as rock powder emerge as sustainable alternatives by enhancing soil quality. In addition to increasing nutrient availability, rock powder interacts with microorganisms in the rhizosphere, playing an essential role in nutrient acquisition and rhizospheric microbial community dynamics. In soybean production, a key crop in Brazil, the demand for eco-efficient alternatives underscores the importance of rock powder. It can not only improve biological activity and influence the rhizospheric microbial community but also foster a beneficial association between microorganisms and roots, providing optimal conditions for soybean growth. Thus, rock powder plays a crucial role in the pursuit of more sustainable and efficient agricultural practices. This study comprises two parts: Study I will evaluate the impact of rock powder addition as a soil conditioner compared to a synthetic fertilizer on plant-soil-microorganism interactions in soybean cultivation (Glycine max (L.) Merrill) through a multi-omics approach. This approach will provide a genomic-level insight into the functionality and taxonomic groups involved in rhizospheric biogeochemical processes, especially when rock powder is added. The investigation involves greenhouse experiment setup, collection of rhizospheric soil samples from soybeans cultivated with rock powder (granite and phonolite) and a traditional fertilizer (potassium chloride - KCl). The methodology includes genetic material extraction, amplicon and transcriptomic library construction, followed by next-generation sequencing on the Illumina platform. Bioinformatics tools will be employed to analyze taxonomic diversity, microbial interactions, and metabolic mechanisms in the root-microorganism-soil relationship. Analysis of differentially expressed genes will provide molecular insights into soybean response to soil conditioning. Lastly, 16S rRNA and ITS sequencing will allow a detailed analysis of microbial community composition and diversity in the rhizosphere, with potential implications for enzymatic assays and functional assessments. Study II aims to validate the findings of the first experiment. In this context, Arabidopsis thaliana will be employed as a model plant to investigate genetic responses observed in the initial study. Functional tests in A. thaliana will be conducted through a greenhouse experiment to assess the response of A. thaliana cultivated under rock powder application, based on previous studies. Subsequently, enzymatic assays and sequencing of 16S rRNA and ITS genes will be conducted. The integration of genomic, transcriptomic, and microbiological data seeks to provide a holistic understanding of the mechanisms underlying plant-soil-microorganism interactions. The results aim to contribute to a deeper understanding of processes influencing soybean development under the influence of rock powder, exploring potential