Strip cropping in organically managed vegetable systems: agronomic and environmental effects

This study evaluated the agro-environmental and economic effectiveness of strips introduced in a diversified organic vegetable system. Two experiments of three experimental years (2018, 2019, 2020) were carried out within the 4-year rotation of MOnsampolo VEgetable organic Long-Term Experiment (MOVE LTE) in Central Italy to test strip cropping vs pure stand. The crop combinations in the two experiments were faba bean (Vicia faba L.)-tomato (Solanum Lycopersicum L.) and common wheat (Triticum aestivum)-zucchini (Cucurbita pepo L.). We determined the productive and economic performances, disease and weed control, nutritional differences and effectiveness in returning carbon to the soil. The two strip cropping systems allowed a better use of resources, enhancing plant biomass and crop residues, particularly for tomato (+24%) and zucchini (+63%). However, the greater plant biomass did not always result in an increase in crop yields. For example, while the wheat-zucchini strip system showed a land equivalent ratio >1 in all three experimental years with a high yield performance in zucchini (+54% of yield), the faba bean-tomato system was more productive in strips only in 2018. On the contrary, this latter system contributed a carbon return >1 in all three experimental years. No significant differences between strip and pure stand systems were observed for fusarium (Fusarium oxysporum f. sp. lycopersici) and oidium (Oidium spp.) diseases on tomato and zucchini crops, respectively, and for weed control. Lastly, greater labor costs associated in both experiments did not affect their profitability (+21% and +319% in faba bean-tomato and wheat-zucchini experiments, respectively). Overall, our findings pointed out that farmers could increase sustainability of their cropping systems with the introduction of a well-designed strip cropping system, which can lead to the reduction of economic risks, greater potential soil carbon and more efficient use of resources on the same land.