Vineyards play a crucial role in the economies, landscapes, and ecosystems of temperate regions. Cover cropping is an agroecological practice that enhances ecosystem services delivery while mitigating the negative impacts associated with grapevine cultivation. This meta-analysis assessed for the first time the influence of cover crops through multiple explanatory variables, including edaphic and climatic factors, vineyard and cover crop management on provisioning, regulating, and supporting ecosystem services in temperate vineyards worldwide. We analyzed data from 64 studies ( n = 1308 paired comparisons) using the natural logarithm of the response ratio [Ln(RR)] as the effect size, with 95% confidence intervals (95% CI) to evaluate the magnitude and significance of response variables. A random-effects model was used for the overall meta-analysis. Effect sizes for explanatory variables were subsequently compared using subgroup meta-analyses with mixed-effects models. Overall, cover crops had no significant effect on provisioning (−0.056; 95% CI: −0.154 to 0.042; p = 0.263), but significantly improved regulating (0.342; 95% CI: 0.075, 0.610; p = 0.012) and supporting ecosystem services (0.124; 95% CI: 0.008, 0.241; p = 0.036). Regulating ecosystem services were particularly enhanced in semiarid climates, organic systems, irrigated vineyards, under high grapevine density and in-row cover crop management, and where cover cropping had been adopted for a medium to long period. Greater gains were also associated with spontaneous vegetation, mixed or non-traditional cover crop species, and termination via green manuring or mowing. Supporting ecosystem services also benefited where cover cropping had been adopted for a medium to long period, particularly under organic farming, with cover crop mixtures, and when terminated via roller-crimping. Among studies assessing multiple ecosystem services, 28% reported win–win outcomes, 17% showed lose–lose scenarios, 42% exhibited trade-offs, whereas 13% did not affect ecosystem services. These results demonstrate the ecological benefits of cover crops in temperate vineyards, especially for regulating and supporting ecosystem services, without compromising grapevine yield.

Environmental benefits can be achieved by organic farming systems; however, weed pressure and timely crop nutrition remain important drawbacks for many field crops. Agroecological practices, such as double cropping (e.g., intercropping and relay cropping), using forage legume species can provide nitrogen (N) to the companion crop through biological N fixation and tackle weed issues by competing for light, water and land. The present study investigated the effect of intercropping (IC) and relay-cropping (RC) systems of durum wheat (Triticum turgidum subsp. durum (Desf.) Husn) and forage legumes (Trifolium subterraneum L., Medicago polymorpha L., and Lotus corniculatus L.) by varying organic N fertilization with the aim to reduce N-requirement and weed pressure and increase wheat grain yield and grain protein content in Mediterranean organic farming systems. N fertilizer significantly improved wheat grain yield and grain protein, while a null effect on legume and weed biomass yields was found. Double cropping (T. durum-M. polymorpha, and T. durum-L. corniculatus) enhanced wheat grain yield as compared to the control and the T. durum-T. subterraneum. IC significantly improved legume yield, grain protein and the land equivalent ratio (LER) and reduced weed dry biomass as compared with the RC and the control. Among legume species, T. subterraneum outperformed the others and was less affected by the wheat’s competitive performance. Nonetheless, M. polymorpha was as effective as T. subterraneum in controlling weeds. Weed dry biomass was linearly reduced by increasing legume yield; the relationship improved by cumulating wheat grain yield to legume yield. Overall, this study indicated that double cropping, especially IC, can be a suitable agroecological practice to tackle weed issues and reduce N-requirement in Mediterranean organic cereal-based systems.

Grasses constitute a key functional group in cover cropping strategies, particularly under the challenging conditions of Mediterranean climates, owing to their drought tolerance, rapid development, high biomass production, and extensive ground cover. Although their role in enhancing ecosystem services and supporting sustainable agroecosystems is increasingly recognized, a comprehensive synthesis specifically addressing Mediterranean climates is still lacking. To evaluate management options for efficient cover cropping strategies and the associated ecosystem services, this systematic review synthesizes evidence from 64 peer-reviewed field studies on grass cover crops, grown as single species or within grass-based mixtures, across three major Mediterranean agroecosystems (vineyards, orchards, and arable cropping systems). The following key points emerged: (1) cool-season grass species, either grain annual cereals or perennial forages, are the most effective at increasing soil organic matter content and nutrient availability, decreasing soil erosion, and suppressing weeds in Mediterranean environments; (2) if not properly managed, grass cover crops can compete with cash crops, immobilize soil N, and decrease crop yield; (3) species selection should be based on specific pedo-climatic characteristics and intended agronomic purposes; (4) despite context-specific differences, recommended management options in Mediterranean climate regions include drill planting, early autumn sowing, an appropriate seeding rate, and timely mechanical termination; and (5) optimizing cover cropping management based on biomass production and C/N ratio can help balance benefits and trade-offs, enabling targeted enhancement of specific ecosystem services. Grasses, when combined with legumes, often deliver even greater ecosystem services than when grown alone, as legumes complement grasses by increasing N availability, improving residue quality, and supporting more balanced biomass production. We conclude that grass cover crops hold considerable promise for promoting sustainable Mediterranean agriculture but require more long-term, multifunctional research to optimize their use.

Water scarcity is increasingly challenging greenhouse tomato production, particularly in Mediterranean and semi-arid regions where irrigation water availability is becoming progressively limited. This study evaluated whether a superabsorbent polymer (SAP) can support water-saving irrigation in tomato grown in coconut fibre. Plants were cultivated in pots under four irrigation amounts (100, 75, 50, and 25% of crop water requirement—WC) combined with two SAP levels (0 and 2 g L⁻¹). Irrigation was managed by a lysimetric control system. Reducing irrigation decreased total fruit yield (averaged across SAP treatments) from 100% WC (1212 g plant⁻¹) to 50–25% WC (914 and 624 g plant⁻¹, respectively), while non-marketable fruit number was unchanged (15.4 fruit plant⁻¹, on average). SAP increased total yield, averaged across irrigation treatments (from 925 to 1022 g plant⁻¹), and marketable fruit number (from 26.3 to 32.3 fruit plant⁻¹), without affecting unitary fruit weight (20.4 g fruit⁻¹, on average). SAP also increased net photosynthesis (from 16.0 to 17.4 µmol CO₂ m⁻² s⁻¹), while stomatal conductance (0.14–0.15 mol H₂O m⁻² s⁻¹) and WUE (4.0 µmol CO₂ mmol⁻¹ H₂O) were not affected by SAP. Total soluble solids increased under severe deficit (7.8 °Brix at 25% WC) and were enhanced by SAP (from 6.9 to 7.6 °Brix), while colour parameters were mainly driven by irrigation. Overall, the irrigation amount was the primary driver of performance. Moderate deficit irrigation (75% WC) maintained a marketable fruit number and total fruit weight comparable to full irrigation (100% WC). SAP amendment acted as a complementary tool to improve marketable production and net photosynthesis across irrigation levels, providing an additive benefit to crop productivity.

Intercropping rhizobia‐inoculated forage legumes in organic wheat systems reduces weed pressure and supplies nitrogen (N) to the companion crop via biological N ₂ fixation (BNF). However, adoption of combined intercropping and rhizobial inoculation remains limited. This 2‐year field study compared durum wheat ( Triticum turgidum L. subsp. durum (Desf.) Husn.), as a sole crop, or intercropped with forage legume ( Trifolium subterraneum L., Trifolium michelianum Savi, or Vicia sativa L.) in southern Italy. Legumes were rhizobia‐inoculated or non‐inoculated. Treatments were evaluated under reduced N fertilization (60 kg N ha ⁻¹ ) or standard N fertilization (120 kg N ha ⁻¹ ). The warmer and drier 2023/2024 season reduced wheat yields but increased grain protein, whereas the wetter 2024/2025 season enhanced yields, BNF (estimated using published empirical relationships linking N ₂ fixation to legume biomass yield and shoot N content), and wheat N recovery efficiency. Regardless of environmental conditions or agronomic treatments, wheat–legume systems consistently reduced weed biomass compared with sole wheat. Inoculated V. sativa and T . subterraneum improved wheat grain yield versus sole wheat, particularly under favorable conditions at reduced N rate. Vicia sativa exhibited the highest BNF, especially when inoculated at the low N rate, whereas T. michelianum showed smaller benefits. Inoculated T . subterraneum showed the highest nodule number and weight, and higher soil nitrate nitrogen (NO ₃ ⁻ ‐N), particularly at the higher N rate. Although results were context‐dependent on environmental conditions, legume living mulches integrated with effective rhizobial inoculation and reduced N fertilization support the agronomic sustainability of organic wheat systems in Mediterranean environments.

Durum wheat straw is an abundant by-product in Mediterranean cereal systems, but its low protein and high fiber content limit its use as ruminant feed. Integrating forage legumes as living mulches in durum wheat may enhance its feeding value through the addition of nutrient-rich legume biomass. A two-year field trial evaluated three forage legumes (Vicia sativa L., Trifolium michelianum Savi, Trifolium subterraneum L.) grown as living mulch with organic durum wheat (Triticum turgidum subsp. durum (Desf.) Husn.) under two NPK fertilization rates (target 60 and 120 kg N ha⁻¹), with or without rhizobial inoculation. Chemical composition and forage quality indices were determined for sole-wheat straw (SB) and legume biomass (LB) and subsequently used to estimate the nutritional characteristics of wheat straw–legume biomass mixtures (TSB). Biomass production was significantly affected by legume species in the first growing season and by legume species and rhizobial inoculation in the second, with Vicia sativa consistently showing the best performances. Correlation analysis showed that increasing LB contribution was significantly associated with all forage quality indices of the resulting TSB. These results indicate that rhizobially inoculated forage legume living mulch may improve the potential use of wheat straw as an on-farm feed resource in Mediterranean organic farming.