Influence of multilayers Bernal and Rhombohedral graphene obtained by green chemistry on the acceleration in the germination process of tomato seeds

Abstract

The environmental ramifications stemming from the application of graphene-based materials have sparked significant interest in recent years. This study delved into assessing the influence of multilayer graphene, specifically focusing on the Bernal (2H) and Rhombohedral (3R) phases, on the germination process of tomato (Solanum lycopersicum) seeds. Multilayers Bernal-Rhombohedral Graphene (MBRG) were synthesized employing green chemistry principles, utilizing the ultrasonication technique operating at 40 kHz within a deionized water solution. Systematic characterization of the phases was conducted via X-ray diffraction, Raman Spectroscopy, TEM, and conductivity measurements. Subsequent administration of MBRG at concentrations ranging from 10 to 500 mgL−1 on tomato seeds revealed an expedited germination process, achieving completion within 3 days. Noteworthy enhancements were observed, including a 12 % absolute increase in germination, a 3 % rise in relative root growth, and a 9 % elevation in the germination index compared to the control. Moreover, a discernible augmentation in root length was evident with escalating concentrations of MBRG, peaking at 50 mgL−1, albeit exhibiting a slight decrement at 500 mgL−1. Additionally, the antioxidant activities of root extracts were assessed across various MBRG concentrations, demonstrating no significant alterations. The outcomes posit that MBRG compositions, comprising 60.44 % (2H) and 39.55 % (3R) phases at specific concentrations, hold promise as a viable additive for expediting early seed germination, thereby presenting a potential sustainable solution in agricultural contexts.