Life cycle assessment of mycorrhizae production

Life cycle assessment of mycorrhizae production Cecilia Girón-Rojas1, Giovanni Russo2 Gabriela Clemente3 Neus Sanjuan 3 1 Universitat Politècnica de Catalunya, DEAB, Escola Superior d’Agricultura de Barcelona, c/ Esteve Terradas 8, Ed, D4, 08860 Castelldefels, Spain. ecgirrojpvnet.upv.es 2 Department of Soil, Plant and Food Sciences (Di.S.S.P.A.)Dipartimento di Scienze Agro-Ambientali e Territoriali, Università University degli Studi di ofBari Aldo Moro, Via Amendola 165/A, 70126 Bari, Italy. giovanni.russo@uniba.it 3Food-UPV, Universitat Politècnica de València. Camino de Vera, s/n. 46022 - Valencia, Spain. nsanjuan@tal.upv.es, gclemen@upv.edu.es E-mail contact address: ecgirrojpvnet.upv.es 1 . I N T R O D U C T I O N The production of mycorrhizae is gaining importance in modern agriculture (Rouphael et al., 2015) due to the search for more environmentally friendly practices. Mycorrhizae are fungi with a symbiosis with plant roots and are used as biostimulants. They have been shown to boost the development and productivity of various plant species (Berruti et al., 2016). These symbiotic associations play a fundamental role in the functioning of terrestrial ecosystems by improving nutrient uptake (Clark & Zeto, 2000; Zakaria M. Solaiman et al., 2014), increasing disease resistance, and improving soil quality. Consequently, its application reduces the dependence on chemical fertilizers and enhances efficiency in using natural resources (Jansa et al., 2003; Noceto et al., 2021). Research on life cycle assessment in the production of mycorrhizae for use as biostimulants needs to be better developed. The main goal of this study is to assess the environmental impacts of mycorrhizal production in vivo for four scenarios. 2 . M E T H O D S The functional unit considered was the production of 10,000 spores. Four scenarios were assessed, the main differences being the mycorrhiza strain, the host plant, the type of substrate, and the fertilization plan. The system boundaries comprise all the processes and inputs needed to produce the inoculum, namely seed disinfection, substrate production and sterilization, fertilizers’ production, and the energy to irrigate and light the plants. For the development of the inventory (Table 1), data were collected from scientific literature. Ecoinvent v3.9 and Sphera database were used for the background processes, and ten impact categories were evaluated with Environmental Footprint 3.1. 3 . R E S U L T S A N D D I S C U S S I O N The impact scores of the four scenarios show slight differences for most of the impact categories (Table 2), with the exceptions commented below. Acidification scores range from 0,007 to 0,015 mole of H+ eq· FU-1, the difference due mainly to higher water use and fertilization in scenario 2. The excessive use of fertilizer causes an increase in scenario 2 in climate change, the values are between 0.4 to 4.32 kg CO2 eq·FU-1; whereas for land use, the results vary between 2 and 26 pt · FU-1 due to the different substrate and fertilization. The scores of fossil resources range from 5.8 to 60.4 MJ· FU-1, although it is mainly due to the electricity production, differences are due to the resources used for fertilizers manufacturing. Water use is to 1.3 and 21 m3 world eq · FU-1 due to different irrigation doses. O N C L U S I O N S From the results, it can be concluded that even following similar processes, changes in the substrate used and t he fertilization plan are crucial to decrease the impacts of mycorrhizae. 5 . A C K N O W L E D G E M E N T S We thank the Ministry of Universities for the support of the "Margarita Salas" program for the training of young doctors. The study forms was supported Partnership for Research and Innovation in the Mediterranean Area (PRIMA) funding for the New AGRoecological approach for soil fertility and biodiversity restoration to improve ECOnomic and social resilience of MEDiterranean farming systems.