Truffle farming and nanomaterials: a new technology for the optimization of the mycorrhization process and release of "helper" microorganisms

Truffle farming is synonymous with specialized plantations where the quality of the starting material, that is the plant with the mycorrhiza, determines its productivity and economic sustainability. The mycorrhizal phase still represents a crucial point in the process and the study of the rhizospheric microbiome in the process of mycorrhizal symbiosis through the action of 'helper' microorganisms is of crucial importance. The TANA project is part of this complex context, in which research groups from the University of Tuscia, Sapienza, in collaboration with the start-up Nanomnia, thanks to funding from LazioInnova regional funding agency for innovation of Regione Lazio, have proposed a new synergistic approach for the enhancement and optimization of truffle farming processes thanks to the combined use of nanotechnologies. Indeed, numerous inorganic compounds, bacteria and viruses contribute to the complexity of the soil biota; among these, bacteria are the most abundant and many of them are classified as MHB (mycorrhiza helper bacteria) because they are able to stimulate the formation of mycorrhizal symbiosis and its vitality. In this context, nanomaterials can act as carriers for bioactive species and at the same time can be effective in stabilizing and protecting encapsulated molecules / microorganisms (fungi and bacteria), favoring their gradual release into the environment. The study of inorganic nanoparticles and polymer / nanoparticle composites, to be used as carriers of microorganisms in the soil, has the main purpose of improving the development of the rhizosphere by providing a consistent source of fungi and bacteria capable of interacting with the root system and the microbiome of the soil. Polysaccharides are among the most stable and most efficient biomaterials to meet the needs that the encapsulation of microorganisms requires. Among these, alginate, a natural polymer extracted from brown algae, is the most used because it is non-toxic to humans and the environment, inexpensive and suitable for encapsulating living cells. It is therefore possible to prepare alginate beads with a controlled diameter and, with a simple methodology, also create formulations by encapsulating mycorrhizogenic fungi and MHB bacteria at the same time. Furthermore, it is possible to encapsulate inorganic nanoparticles (AgNPs) which at low doses show beneficial effects on the growth and development of the rhizosphere thanks to a slow controlled release. The specific objective of TANA is therefore to develop a new biotechnological manufacturing product based on the use of nanotechnologies, functional to the truffle supply chain for Tuber melanosporum (precious black truffle) in the process phase that concerns the production of high quality mycorrhized plants, for productive plantations.