Farm and industrial residues must be adequately managed to avoid negative environmental implications. In this study, our objective was to evaluate (i) the impact of the co-production of vermicompost using grape bagasse and biochar (BC) on the yield and biochemical, chemical, and biological properties of vermicompost; (ii) the effect of BC on earthworms (Eisenia fetida Sav.). The vermicompost was co-produced over 5 months (n = 4 per treatment) using (i) grape bagasse as the substrate, (ii) earthworms (Eisenia fetida Sav.), and (iii) three BCs (eucalyptus sawdust BC, pig manure BC, and carbonaceous material from poultry litter CM) at 2% (w/w). A control without BC was included. The chemical, microbiological (activity and respiration), enzymatic properties, and enzymatic indices were characterized. After the incubation period, vermicompost yield increased with the application of the three BCs (25% on average). The number of adult earthworms was not affected by any of the BCs. Compared to treatments without BC, those with pig manure BC and eucalyptus BC resulted in maintained or significantly decreased enzymatic activity, indicating that the vermicompost was at an advanced stage of maturity. Eucalyptus BC significantly enriched the C content of the vermicompost by 4.3%, maintaining respiration rates at 18% lower than the treatment without BC. Additionally, pig manure BC generated the lowest respiration rate in the vermicompost (20% lower). We conclude that BC has a positive influence on the vermicompost process, stabilizing organic matter (especially pig manure BC) and improving the potential of vermicompost to store C (when high-C-content BCs are applied).

Water scarcity poses a significant threat to kiwifruit production, especially in Mediterranean climates. This study investigated the impact of late-season regulated deficit irrigation (RDI) on water use efficiency and fruit quality of yellow-fleshed kiwifruit (Actinidia chinensis cv. Soreli) over two seasons in central Chile. Four irrigation treatments were applied during fruit ripening: full irrigation (Control), moderate deficits for three or five weeks (D50S and D50L), and complete irrigation suspension for three weeks (D100). While D100 had minimal impact on stomatal conductance, it significantly reduced stem and leaf water potentials, indicating severe water stress. D100 treatment also showed the highest intrinsic water use efficiency (via δ13C enrichment) and improved water productivity by up to 20%. Fruits from D100 and D50S had higher soluble solids (up to 2.0 °Brix) without compromising firmness or yield. Sensory evaluations indicated greater consumer acceptance in water-stressed treatments, especially D100, due to enhanced color and flavor. Principal component analysis confirmed that moderate-to-severe-water stress correlated with favorable sensory profiles. These findings suggest that short-term, late-season water deficits can enhance fruit quality and water use efficiency without reducing yield, offering a sustainable strategy for kiwifruit production under increasing water limitations.

Chile, the leading exporter of cherries (Prunus avium L.) in the southern hemisphere, faces sustained variations in precipitation patterns and high evaporative demand in its productive areas. The low availability of water during the period of highest environmental demand makes it essential to reduce or suspend irrigation applications. In this scenario, regulated deficit irrigation (RDI) after harvest is an efficient strategy for optimizing water use without compromising orchard yields. This study was conducted over three consecutive seasons in a traditional commercial orchard of ‘Santina’ cherry trees grafted onto Colt rootstock, evaluating the effect of two levels of RDI, moderate (MDI) and severe (SDI), on productive and ecophysiological parameters. Both treatments resulted in water savings of between 10% and 28%, without negatively affecting yield or fruit quality. The SDI treatment, despite reaching higher levels of cumulative water stress, improved intrinsic water use efficiency while maintaining stable photosynthetic efficiency. In addition, an increase in the abundance of fine roots and beneficial rhizosphere bacteria populations, such as Azospirillum and Bacillus, was observed, suggesting the activation of water resilience mechanisms mediated by plant–microbiota interaction, possibly associated with stress-induced ecological memory and microbial legacy effects. These results position after-harvest RDI as a sustainable tool for coping with climate variability and water scarcity in commercial cherry orchards.