Citation: Quintarelli, V.; Radicetti, E.; Allevato, E.; Stazi, S.R.; Haider, G.; Abideen, Z.; Bibi, S.; Jamal, A.; Mancinelli, R. Cover Crops for Sustainable Cropping Systems: A Review. Agriculture 2022, 12, 2076. https://doi.org/10.3390/ agriculture12122076 Academic Editor: Manuel Ângelo Rosa Rodrigues Received: 1 November 2022 Accepted: 30 November 2022 Published: 3 December 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). agriculture Review Cover Crops for Sustainable Cropping Systems: A Review Valentina Quintarelli 1 , Emanuele Radicetti 1, * , Enrica Allevato 2 , Silvia Rita Stazi 1 , Ghulam Haider 3 , Zainul Abideen 4 , Safia Bibi 3 , Aftab Jamal 5 and Roberto Mancinelli 6 1 Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Luigi Borsari n. 46, 44121 Ferrara, Italy 2 Department of Environmental and Prevention Sciences, University of Ferrara, Via Luigi Borsari n. 46, 44121 Ferrara, Italy 3 Department of Plant Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad 44000, Pakistan 4 Dr. Muhammed Ajmal Khan, Institute of Sustainable Halophyte Utilization, University of Karachi, Karachi 75270, Pakistan 5 Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of the Yangtze River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China 6 Department of Agricultural and Forestry Sciences, University of Tuscia, Via San Camillo de Lellis snc, 01100 Viterbo, Italy * Correspondence: emanuele.radicetti@unife.it Abstract: Cover cropping is a promising and sustainable agronomic practice to ameliorate soil health and crop performances in agro-ecosystems. Indeed, cover crops (CCs) may regulate several ecosystem services such as nutrient cycling, soil fertility, moderation of extreme meteorological events, pollination, and climate and water regulation; in addition, CCs are also used as forage crops and have considerable effects on plant and soil biodiversity. However, to achieve the desired effects on agro-ecosystems, cover cropping should be carefully adopted by considering the specie choice, period of cultivation, and termination method based on site, farm, or purpose-specific. The main objective of this manuscript is to analyze the effects of modern agriculture on soil and environmental health and how cover crops can support sustainable cropping systems and global food security. In addition, it focuses on how the incorporation of cover crops into conventional cropping systems can help in the diversification of crops and assist in mitigating the environmental effects of cropping systems. Finally, this review thoroughly investigates the potential effects of CCs on environmental sustainability, which can be an important source of information for sustainable crop production and food security. Keywords: agro-ecosystems; soil cover; subsidiary crops; crop yield; carbon sequestration; nutrient cycle; greenhouse gas emissions 1. Introduction Global agri-food systems are facing challenges in realizing food chains for feeding the growing population, which is expected to be 10 billion people by 2050 [1]. At the same time, agricultural systems need to be managed by a sustainable approach to reducing external inputs, such as fossil fuels, and non-judicious use of mineral fertilizers and pes- ticides. In addition, environmental concerns such as greenhouse gas emissions (GHGs), nutrient leaching, especially nitrogen, and its associated environmental pollution should be addressed by means of sustainable practices [2]. The United States Department of Agriculture (USDA) defines conventional farming systems as “agricultural practices which include the use of synthetic chemical fertilizers, pesticides, herbicides, and other continual inputs, genetically modified organisms, con- centrated animal feeding operations, heavy irrigation, intensive tillage, or concentrated monoculture production” [3]. In fact, these approaches to managing agricultural lands are Agriculture 2022, 12, 2076. https://doi.org/10.3390/agriculture12122076 https://www.mdpi.com/journal/agriculture