TY - THES A1 - Nidola, Marta T1 - Frass upcycling: study on the properties of frass and its use as fertilizer and soil amendment in agriculture N2 - Frass, as by-product of the emerging insect market, has been used as fertiliser worldwide. However, the impacts on soil microbial community structure and activity have been not yet well characterized. The aim of this study was to assess the effects that frass from black soldier fly reared on 3 different diets may cause when applied fresh and dried (70°C) on a sandy loam soil, in 2 application rates (0.2 and 2% w/w). For that, frass was chemically characterized before a 28-days incubation, at the end of which samples were analysed from the chemical and biological point of view. It was found that thermal treatments and diets didn’t vary significantly in microbiota stimulation, even though a chemical analysis would suggest the potential for enriched-frass from pig effluent and wheat bran to encourage microorganisms differently from beer & coffee diet. Furthermore, fresh frass contrarily to what expected didn’t contribute with living microorganisms to enhance microbial activity and growth. However, a difference was reported for the application rates, with the 2% leading to more mineralisation than control. A trend for 2% dried frass from B&C was found, indicating the establishment of an efficient community of fungi slowly mineralizing recalcitrant and exhausted frass. Results indicate that more studies testing application rates ranging between 2 and 2.5% have to be conducted. In fact, there is evidence that BSFF between the mentioned application rates could enhance a fast microbial growth leading to a substantial mineralisation of frass, thus availability of nutrients in the short and long term. Y1 - 2021 ER -