Evaluación del impacto sobre el suelo y el rendimiento de un cultivo de maíz dulce para choclo fresco (Zea mays) con vicia (Vicia villosa) en un planteo hortícola comercial del suroeste de Río Negro.

Abstract

The earliest known agricultural systems consisted of mixed crops of desirable species that would meet the community's food, fiber, and other needs and—to a certain extent—mimic the natural ecosystem and its diversity. In this historical context, monocultures are a relatively recent innovation (Francis, 1989). Currently, multiple cropping occupies most of the cultivated areas in West Africa. In tropical Latin America, a large portion of staple crops are produced under this system. Multiple cropping can also be found in temperate zones in relatively large, mechanized production units with access to capital markets (Liebman, 1999). Multiple cropping is a tool for intensification over time and space that can be summarized as the planting of more than two crops in the same year on the same plot. This intensification can be carried out either as sequential or intercropping. Sequential crops can be double, triple, or quadruple cropped depending on the number of harvests per year, and in these cases, intensification occurs in the temporal dimension (Francis, 1989). Within this sequence of crops grown consecutively on the same site, crops that provide other services are often incorporated, currently referred to as service crops (SC). SCs are herbaceous crops, mostly grasses and legumes, planted in rotation between two cash crops. SCs have traditionally been cultivated for various purposes, such as preventing erosion, increasing soil carbon and nitrogen, reducing nitrate leaching, and increasing soil porosity (Ruffo & Parsons, 2004). Like a wide variety of technologies, cover crops have been used since ancient times by various cultures who observed how this practice improved crop yields and recovered impoverished lands (Haider, Cheema, & Farooq, 2019). Cover crops were created to keep the soil covered during fallow periods between harvest crops, and for this reason, they were originally called cover crops. However, with their repeated use, it has been observed that these crops generate multiple benefits, and different names have been proposed based on this. Due to their ability to absorb, retain, and immobilize nutrients from the soil, preventing their loss, they have been called trap crops; because they can serve several purposes simultaneously, they have been called multipurpose crops (Pinto 2012); and more recently, they have begun to be called service crops, since in addition to referring to their multiple purposes, they also refer to the ecological services they provide (Pinto & Piñeiro 2018). (Pinto & Piñeiro, Ecological intensification in the agroecosystems of the Pampas region: the role of service crops, 2018) (Pinto, Evaluation of biological nitrogen fixation and root production in different service crops and their effects on soil organic C and N reserves, 2012) Multiple crops also include intercropping, in which intensification occurs in both temporal and spatial dimensions. These include mixed intercropping, row, strip, and relay intercropping (Francis, 1989). The key to these polycultures is that they must be planted with the necessary spatial proximity to ensure competition or complementarity, thereby increasing overall yields while creating a more sustainable system that conserves resources (Álvarez & Alayon Luaces, 2020).