Biogenic volatile organic compounds emitted by basil grown in a vertical farm under two different red : blue LED ratios

Abstract

Unidad de excelencia María de Maeztu CEX2019-000940-M

Vertical Farms (VFs) are emerging as innovative solutions for local food production, with integrated LED lighting potentially enhancing crop yield and quality, such as basil. However, indoor cultivation can increase Biogenic Volatile Organic Compound (BVOC) emissions, affecting air quality. This study examined the effects of two red and blue light ratios (RB1 and RB3) on BVOC emissions produced by basil cultivation, comparing levels with European regulatory thresholds. BVOC emissions were measured at young and mature plant stages, with sampling intervals of 5, 10, and 15 minutes, alongside monitoring of physiological and environmental parameters. Representative BVOCs compounds were investigated. Results showed higher BVOC emissions under RB1 during the young stage and under RB3 at maturity. However, young plants exposed to RB1 emitted more lipoxygenase derivatives, while mature plants under RB3 increased o-cymene and 1.8-cineole emission. Nevertheless, higher emissions and stomatal conductance observed under RB3 highlighted the significant role on plant stimulation excited by red light. Temperature and relative humidity had a general negative impact on BVOC emissions and the stomatal conductance, whereas CO2 relationship was unclear. Overall, emissions decreased over time. On average, BVOC emissions were below the Lower Concentrations of Interest (LCIs). Once lipoxygenase derivative emissions exceeded given threshold under RB1 light. Occasional peaks of sesquiterpenes and 1.8-cineole were detected but were not remarkable along the cultivation cycle. Based on these findings, health risk concerns due to BVOCs emission exposure associated to indoor agriculture are believed to be minimal.