Molybdenum supply and biological fixation of nitrogen by two Brazilian common bean cultivars

Abstract

The common bean has been considered to have low biological nitrogen fixation capacity; however, this process can be made more effective with molybdenum (Mo) supplementation. The objective of this study was to evaluate the influence of Mo rates on the growth and biological nitrogen fixation by two Brazilian common bean cultivars using the 15N isotope dilution technique. The experiment was performed in 2014 in a completely randomized design arranged in a 5 x 3 factorial scheme, corresponding to 5 rates of Mo (control, 40, 80, 120 and 240 g ha-1), the common bean cultivars Aporé, Ouro Negro and NORH-54 (a non-nodulating common bean cultivar), and three replicates. The application of Mo and the inoculation with rhizobia strains contributed to improving nitrogen fixation and grain weight. The cultivar Ouro Negro showed a higher number and weight of nodules and a higher amount of nitrogen derived from the atmosphere than the cultivar Aporé. The biological nitrogen fixation of Aporé was more dependent on the application of Mo. These results indicated that inoculation with Rhizobium strains and Mo supply effectively contributed to biological nitrogen fixation and improving grain production.

Evaluating the Effectiveness of Rhizobium Inoculants and Micronutrients as Technologies for Nepalese Common Bean Smallholder Farmers in the Real-World Context of Highly Variable Hillside Environments and Indigenous Farming Practices

“…Increases in nodule number, nodule dry weight, and SNF in common bean have been observed with the application of Mo [30][31][32][33] and B [34,35]. However, in our study, application of B and Mo alone did not significantly increase nodulation in common bean, although it had a slight positive impact on root and shoot dry weight at the flowering stage.…”

Genome-Wide Association Studies Detect Multiple QTLs for Productivity in Mesoamerican Diversity Panel of Common Bean Under Drought Stress

“…This reinforces the fact that landraces remain a vital resource for contemporary plant breeding and demand permanent conservation and knowledge of their genetic variability ( Villa et al, 2005 ; Azeez et al, 2018 ). Regarding the Ouro Negro cultivar, from Honduras, which has black grains and a normal cultivation cycle (80–100 days; Amaro et al, 2015 ), in addition to standing out for disease resistance ( Valentini et al, 2017 ), it also has high capacity to fix nitrogen ( Da Silva et al, 2017 ), combining a number of attributes for plant breeding.…”

Molybdenum Foliar Fertilization Improves Photosynthetic Metabolism and Grain Yields of Field-Grown Soybean and Maize

“…Mo is typically applied with the aim of stimulating biological nitrogen fixation (BNF) and nitrate reduction ( Calonego et al, 2010 ; Mercante et al, 2011 ; Crusciol et al, 2019 ). Under Brazilian field conditions, the application of Mo via seed or leaves has been shown to be efficient in increasing nodulation, nitrate reductase activity, protein content, leaf area, number of pods, and grain yield ( Calonego et al, 2010 ; Almeida et al, 2013 ; Silva et al, 2017 ; Crusciol et al, 2019 ); however, recent research has demonstrated that Mo also directly impacts photosynthesis due to its involvement in chlorophyll biosynthesis and stability of the photosynthetic apparatus ( Yu et al, 2006 ; Imran et al, 2019 ). In addition, enhancing photosynthesis by adding Mo increases water use efficiency (WUE), leading to greater tolerance of abiotic stresses ( Wu et al, 2020 ).…”