LAUSR

The common bean is considered a staple food for more than 300 million people in Latin America and Africa, being an important source of protein, fibre, carbohydrates, and minerals (Celmeli et al., 2018; Mukankusi et al., 2019). Although it is one of the most widely produced leguminous crops in the world, the common bean is predominantly cultivated by small farmers, usually in marginal regions, where various biotic and abiotic factors often affect crop productivity (Androcioli et al., 2020; Beebe et al., 2009; Miklas et al., 2006). Stress caused by soil nitrogen (N) deficiency is considered as the main limiting abiotic factor responsible for low productivity of common bean worldwide (Leal et al., 2019). N is the most important element required by common bean crops (Barros et al., 2018; Chekanai et al., 2018). Although common bean plants can fix atmospheric N (N2) due to symbiotic interactions with bacteria of the genus Rhizobium (Hungria et al., 2003; Korir et al., 2017), fixation efficiency is generally low compared with other legumes, and N fertilization is recommended to meet the nutritional requirements of the plant (Appelbaum, 2018). Thus, several studies have highlighted the positive effects of N in increasing common bean plant productivity (Chekanai et al., 2018; Received: 24 December 2020 | Revised: 17 February 2021 | Accepted: 26 February 2021 DOI: 10.1111/pbr.12916