Abstract Phosphorus scarcity necessitates sustainable alternatives like struvite (MgNH4PO46H2O) recovered from waste streams. This study evaluated the efficacy of waste-derived organo-mineral fertilizers containing struvite on greenhouse-grown baby leaf lettuce (Lactuca sativa L.) and radish (Raphanus sativus L.) quality in Bosnia and Herzegovina, Italy, and Spain. Results demonstrated that struvite performed comparably to or better than conventional inputs, significantly increasing P concentration in radish across all sites (up to ∼4 g kg–1 DW) and in lettuce in most locations. Struvite maintained or enhanced photosynthetic profiles, maximizing total chlorophyll in B&H and Italy lettuce. Multivariate analysis (PLS-DA) revealed crop-specific metabolic shifts, notably reducing lipid peroxidation (malondialdehyde) in struvite-fertilized lettuce in specific regions while enhancing radish antioxidant flavonoids in Italy (reaching ∼1.2 mg CE g–1 FW). Struvite consistently proved to be a highly bioavailable P source that maintains or enhances vegetable nutritional and antioxidant quality, facilitating the transition toward circular agricultural systems.
Abstract Achieving localized delivery of signaling molecules in plants while obtaining spatially resolved, non-invasive readout of physiological responses remains a key challenge due to limitations in conventional methods for exogenous biomolecule application. These approaches typically rely on solution-based delivery or systemic treatments, which limit spatial precision and can disrupt the native physiological environment, making it difficult to study signal propagation. Here, we use the capillary organic electronic ion pump (c-OEIP) for localized, electronically controlled dry delivery of the phytohormone abscisic acid (ABA) in intact succulent plants. By combining the c-OEIP technology with infrared thermography, we obtain real-time, spatially resolved monitoring of physiological responses. We demonstrate this approach in Kalanchoë blossfeldiana, a drought-tolerant succulent species whose stomatal responses to exogenous signaling molecules remain poorly understood. Our results show that ABA delivery triggers stomatal closure during the day, consistent with observations in non-succulent plants. This work establishes a minimally invasive platform that combines bioelectronic delivery with spatially resolved readout, enabling spatiotemporal mapping of plant responses.
Abstract The overuse of mineral fertilizers represents significant environmental and economic concerns, highlighting the necessity of sustainable nutrient management. This study evaluated the biostimulant potential of bioproducts (BPs) from solid anaerobic digestate in greenhouse tomato cultivation to maintain productivity with reduced fertilization. Trials were conducted over two cycles, with soil application of BPs, combined with 100 or 60% of standard mineral fertilization (MF). Reducing MF by 40% resulted in a decrease in marketable yield; however, the combination of BPs with 60% MF compensated for this reduction, achieving yields comparable to the control in both growing cycles. Pigment content decreased under reduced MF, but BP-treated plants exhibited higher protein accumulation and increased enzymatic activities involved in nitrogen assimilation, suggesting enhanced nitrogen use efficiency. Overall, BPs acted as effective plant biostimulants, enabling a 40% reduction in mineral fertilizer input without compromising total yield or fruit quality, supporting a more sustainable tomato production.
Abstract This study evaluated the effects of different doses of Bradyrhizobium japonicum and Azospirillum brasilense, applied individually or in co-inoculation, on the physicochemical and physiological quality of soybean grains of the soybean genotypes BMX Zeus and BMX Valente. Grain quality was assessed through proximate composition, physiological parameters, and bioactive compounds. Significant effects of genotype and inoculation dose were observed (p < 0.05). Genotypic differences were observed independently of inoculation response. Overall, BMX Valente exhibited higher crude protein (41.45%), thousand-grain weight (191.01 g), and test weight (600.08 kg·m–3), together with lower electrical conductivity and free acidity. In contrast, BMX Zeus showed greater responsiveness to inoculation, with soluble protein reaching 80.87% and total carotenoids 14.30 µg β-carotene·g–1 under specific treatments. Excessive doses of B. japonicum alone negatively affected grain stability. Multivariate analysis identified the combination of A. brasilense (4.0 g·kg–1 of seeds) and B. japonicum (18.0 g·kg–1 of seeds) as the most favorable treatment, providing the best balance between physiological performance and grain quality.
