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In sustainable/organic farming systems, Agro-ecological Service Crops (ASC) may provide many beneficial ecosystem services, when they are introduced as buffer zones, living mulches or break crops. This outlook paper focuses on: i) the role of ASC genotype and mixtures as catch crops for soil mineral nitrogen (NO 3 -) surplus, which is returned to the system after their termination; ii) living mulches and break crops management strategies, particularly comparing ploughing under (green manure) with termination by roller crimper; iii) summary of three recent case studies that have assessed the effectiveness of ASC management by no-till with roller crimper for tomato, zucchini and melon crops, under Mediterranean conditions. Recently, in central Italy yield and quality results on organic tomato indicated that this crop was suitable following termination of leguminous ASC by roller crimping. Similarly, this ASC management increased yield by about 70% compared to green manure in zucchini crop. In southern Italy, no substantial differences were found in the ASC management and organic fertilizer interactions in organic melon, confirming the suitability of matching these strategies to sustain crop production. More studies should be encouraged to further empower the use of ASC in a wide range of agro-climatic conditions. Furthermore, additional studies on the roller crimper should be performed, mainly to understand the dynamic of N mineralisation in the soil-mulch interface and synchronisation of N release with cash crop N requirements. Finally, Decision Supporting Systems (DSS) for ASC introduction into vegetable cropping systems should be developed.

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Integrating cover crops into vegetable cropping systems can provide a wide range of ecological services, of which weed management is a key component. Cover crop effects on weed control, however, are dependent on termination methods and weed species present in specific cropping seasons. A 2-year weed management experiment with two cultivars of organic zucchini (Cucurbita pepo L.) in central Italy was carried out to compare the effect of a barley (Hordeum distichum L.) cover crop terminated with a modified roller-crimper (RC) to incorporated barley as green manure (GM) and a tilled control left fallow (FA) in the off-season. The effects of cover-crop management on crop competitiveness, yields and weed populations were evaluated by direct measurement, visual estimation and competition index methods. Results showed a significant reduction in weed biomass (>80%) and weed abundance with the RC compared to the GM and FA treatments. Moreover, the RC barley mulch maintained weed control in zucchini plots even under high weed pressure, as determined by the agronomic tolerance to competition (ATC) value of 67% in the RC treatment compared to 40 and 34% in the FA and GM treatments, respectively, averaged over both years of the experiment. The competitive balance (Cb), which quantified the ability of the zucchini crop to compete with weed populations, was also greater (+0.37) in the RC treatment compared to FA (−0.87) and GM (−0.69) treatments over the same period. Zucchini crop biomass was greatest in the RC treatment in 2011. Zucchini fruit yields varied from an average over both years of 1.4 Mg ha−1 in the RC treatment to 0.7 Mg ha−1 in the GM treatment, but yields in the FA treatment, 1.2 Mg ha−1, did not differ from the RC treatment. No differences in yield between ‘Dietary’ and ‘Every’ zucchini, or any significant interactions between cultivar and cover management related to fruit biomass, were observed. Our findings suggested the viability of the modified RC in creating a barley cover-crop mulch to effectively manage weeds and enhance yields in transplanted zucchini.