Evaluación del uso de cultivo de cobertura - laboreo reducido y mulching con manejo orgánico sobre el rendimiento del cultivo de calabacín y la calidad del suelo

The rotation of horticultural crops with cover crops and reduced tillage (CC-RT) is a strategic practice in agroecological systems, but its adoption is limited due to, among other factors, inconsistent results and often low yields. This study aimed to contribute to the development and validation of this technology in an agroecological system by analyzing its impact on the physical, chemical, and biological properties of the soil, as well as on the yield of zucchini squash (Cucurbita moschata Duch). The experiment was conducted at the Centro Regional Sur of the Faculty of Agronomy, Uruguay. The CC-RT system was tested using two cover crop seeding densities (D1 and D2), additional mulch (D2+M), and bare soil (BS). Regarding physical properties, bulk density and penetration resistance remained below critical thresholds for root growth across all treatments, indicating favorable conditions for root exploration and adequate aeration of the soil profile. Soil chemical and biological properties showed a dynamic response influenced by the quality of cover crop residues and environmental conditions. During winter, high basal respiration (BR) and nitrogen mineralization potential (NMP) were recorded; in spring, a peak of mineral N—mainly ammonium—was associated with the rapid decomposition of lupine residues; and in summer, despite high temperatures, treatments with greater surface cover maintained higher overall microbial activity, demonstrating that maintaining soil cover enhances the biological health of the system. Yields ranged from 45 to 49 Mg/ha. Although total yield did not differ among treatments, differences in yield components (fruit number and weight) were observed, indicating variations in the systemic functioning of the crop. The results position CC-RT and mulching as promising technologies for agroecological transition, demonstrating that it is possible to sustain high yields and improve soil quality without relying on external inputs, thereby contributing to the development of more sustainable horticultural systems.