Recycled water use with added microbial consortia in the cultivation of aromatic plants

Research objective: This research aims to evaluate the potential of biologically purified water with added beneficial microorganisms for soil and plants for possible use in agriculture. In such a way that this type of water, which is not always accepted by growers, can instead be positively perceived by technicians in the sector and by those who often have no other water resources to irrigate their plants.

Materials and Methods: The experiments, which began in April 2023, were conducted to the Abbey of S. Antimo in Piombino (LI) on different types of aromatic plants (rosemary, sage, mint, thyme). The experimental groups were: control; aqueduct water; aqueduct water with added microorganisms; recycled water; recycled water with added microorganisms. On 17 May 2023, plant height, number of leaves, vegetative weight, volume and length of roots, number of microorganisms in the substrate, number of dead plants and pH of the substrate were determined.

Results and Discussion: The experiment showed that it is possible to use recycled water supplemented with microorganisms to significantly improve plant height, leaf number, and vegetative and root biomass, reducing plant mortality on aromatic species such as mint, rosemary, thyme and sage. In general, a significant increase in plant height and number of leaves as well as vegetative and root biomass was observed in plants treated with microorganisms

The trial significantly showed how water inoculated with plant-stimulating microorganisms can significantly increase the vegetative and root biomass of various aromatic plant species. This aspect was also found in other horticultural species.

Conclusions: The possible use of these waters in agriculture requires a careful study of the microbial communities present in them, which are often not suitable for plant growth. This experiment aimed to assess whether the use of plant-specific micro-organisms added to previously biologically treated water could improve the adaptation and growth performance of certain aromatic species. The results were significant and certainly deserve further studies on other horticultural species.