Use efficiency and responsivity to nitrogen of common bean cultivars

Abstract

Common beans are the main source of protein in underdeveloped countries, and nitrogen (N) is one of the nutrients the most limits the productivity of this crop. This study, under field conditions, aimed to: a) determinate through efficiency indices how N is used by 16 cultivars of common beans; and b) classify these cultivars regarding use efficiency and responsivity to N application. The experimental design was in randomized blocks in split-plot scheme, with four replicates. Main plots consisted of 16 cultivars of common beans commercially classified as ‘Carioca type’. Subplots comprised two rates of N: 20 and 120 kg ha-1 applied as top-dressing. The evaluations were number of pods per plant and grains per pod, hundred-grain weight, shoots dry matter at full flowering, straw and grains dry matter at physiological maturity and grain yield. Based on the dry matter and its nutrient contents, the N accumulations were calculated in shoots and grains. The agronomic, physiological, agro-physiological, recovery and use efficiencies of N were calculated. Cultivar BRSMG Uai stands out by agronomic, physiological, recovery and use efficiencies of N. Genotypes BRSMG Uai, BRS FC402, IPR Campos Gerais, IPR Maracanã and TAA Bola Cheia are efficient and responsive to top-dressing N application.

Genetic Progress of Seed Yield and Nitrogen Use Efficiency of Brazilian carioca Common Bean Cultivars Using Bayesian Approaches

“…SY increased under high N top-dressing (17.51%), corroborating a previous study that reported N as the macroelement that most influences SY in common bean crop (Barros et al, 2018). Similar results were also observed for 16 Brazilian carioca common bean cultivars which observed an increase of approximately 21.71% in plants under high N condition (Leal et al, 2019).…”

Top-Dressing Nitrogen Doses in Maize Sown in Single and Double Rows and Cultivated in Winter

“…The use of efficiency indices enables a better understanding of how the nutrient is utilized and for which organs it is destined in plants (Leal et al, 2019).…”

“…especially for physiological and utilization efficiencies, indicates that the spatial arrangement used, with the super-early hybrid of erect leaf architecture, did not favor the increase in leaf area, making it difficult for plants in the doublerow system to convert their better N nutrition into compounds such as proteins and carbohydrates in leaves and grains. Physiological efficiency indicates the amount of shoot dry mass increased for each kg of N accumulated in the shoots, and the utilization efficiency represents the amount of shoot dry mass increased for each kg of N applied via fertilizers(Leal et al, 2019).In general, the N use efficiency decreased with the increase in the dose applied as topdressing, as observed byFarinelli & Lemos (2010).Carvalho et al (2012) obtained a similar result when comparing 10 maize cultivars subjected to top-dressing fertilization with 40 and 160 kg ha -1 . The authors observed that there was no significant difference between the cultivars evaluated for the N content in the shoot dry mass.…”

Cobertura Nitrogenada Em Diferentes Estádios Fenológicos Do Feijoeiro Comum Altera Produtividade E Qualidade De Grãos

“…Além disso, estudos de Leal et al (2019) sobre eficiência e responsividade ao N por cultivares de feijoeiro comum classificaram a cultivar Pérola como eficiente no uso do N aplicado em cobertura. Outro ponto importante é que é comum a ausência de resposta significativa para o N foliar em estudos de adubação nitrogenada em feijoeiro comum, já que pode ocorrer efeito de diluição com o aumento de matéria seca proporcionado pela aplicação de N (PEREZ et.…”