ABSTRACT Knowledge of the interactions between soil physical properties and yield performance in agricultural crops is very important for the adoption of appropriate management practices. This study aimed to evaluate the linear and spatial correlations between some soil physical attributes, straw production in the palisade grass (Urochloa brizantha), and grain yield of winter common bean in succession to the grass under an irrigated no-till system in an Oxisol Haplorthox in the Cerrado lowlands region of Brazil. The plant attributes determined were dry matter yield of U. brizantha (DMY), and grain yield (GY) and final plant population (PP) of winter common bean. The soil physical attributes, evaluated at 0.0-0.10 m and 0.10-0.20 m, were soil bulk density (BD), macroporosity (MA), microporosity (MI), total porosity (TP), penetration resistance (PR), gravimetric water content (GW), and volumetric water content (VW). A geostatistical grid with 124 sampling points was installed to collect the soil and plant data in an area of 4000 m2. The remaining straw amount of palisade grass exhibited an inverse linear correlation with bean yield and bean plant population when the bean was cultivated in succession. However, no spatial correlations were observed among the attributes. The common bean yield had a direct linear correlation with gravimetric water content in the 0.10-0.20 m soil layer. From a spatial point of view, winter bean yield showed a strong dependence on the distribution of the volumetric water content in the 0-0.10 m soil layer. | RESUMO O conhecimento das interações entre os atributos físicos do solo e o desempenho produtivo das culturas agrícolas é de suma importância para a adoção de práticas de manejo adequadas. Deste modo, o presente estudo objetivou avaliar as correlações lineares e espaciais entre alguns atributos físicos do solo com a produção de palhada do capim-marandu (Urochloa brizantha) e a produtividade de grãos do feijoeiro de inverno cultivado em sucessão ao capim sob sistema plantio direto na região de Cerrado de baixa altitude, em condições irrigadas em um Latossolo Vermelho distroférrico. Os atributos das plantas foram: a produtividade de matéria seca (PMS) para a Urochloa brizantha, e para o feijoeiro a produtividade de grãos (PRO) e a população de plantas (PP). Os atributos físicos do solo avaliados nas camadas de 0,0-0,10 m e 0,10-0,20 m de profundidade foram: a densidade do solo (DS), macroporosidade (MA), microporosidade (MI), porosidade total (PT), resistência à penetração (RP), umidade gravimétrica (UG) e umidade volumétrica (UV). Para coleta dos dados foi instalada uma rede amostral contendo 124 pontos, em uma área de 4000 m2. A palhada remanescente do capim-marandu apresentou correlação linear inversa com os atributos do feijoeiro de inverno (população de plantas e a produtividade de grãos). Entretanto, sem correlação espacial sobre tais atributos. A produtividade de feijão teve correlação linear direta com a umidade gravimétrica do solo na camada de 0,10-0,20 m. Do ponto de vista espacial, a produtividade do feijoeiro de inverno apresentou forte dependência com a distribuição da umidade volumétrica na camada de 0-0,10m.

Knowledge of the interactions between soil physical properties and yield performance in agricultural crops is very important for the adoption of appropriate management practices. This study aimed to evaluate the linear and spatial correlations between some soil physical attributes, straw production in the palisade grass (Urochloa brizantha), and grain yield of winter common bean in succession to the grass under an irrigated no-till system in an Oxisol Haplorthox in the Cerrado lowlands region of Brazil. The plant attributes determined were dry matter yield of U. brizantha (DMY), and grain yield (GY) and final plant population (PP) of winter common bean. The soil physical attributes, evaluated at 0.0-0.10 m and 0.10-0.20 m, were soil bulk density (BD), macroporosity (MA), microporosity (MI), total porosity (TP), penetration resistance (PR), gravimetric water content (GW), and volumetric water content (VW). A geostatistical grid with 124 sampling points was installed to collect the soil and plant data in an area of 4000 m2. The remaining straw amount of palisade grass exhibited an inverse linear correlation with bean yield and bean plant population when the bean was cultivated in succession. However, no spatial correlations were observed among the attributes. The common bean yield had a direct linear correlation with gravimetric water content in the 0.10-0.20 m soil layer. From a spatial point of view, winter bean yield showed a strong dependence on the distribution of the volumetric water content in the 0-0.10 m soil layer.

RESUMO O feijoeiro-comum requer altos níveis de nitrogênio (N) para alcançar elevadas produtividades, os quais podem ser supridos, ao menos parcialmente, pela fixação biológica de N (FBN). Com o objetivo de avaliar os efeitos de diferentes plantas de cobertura e épocas de dessecação no desempenho agronômico do feijoeiro-comum inoculado com rizóbio, foram conduzidos dois experimentos em campo, na safra de inverno 2015. Os experimentos foram implantados em delineamento de blocos ao acaso com quatro repetições, em esquema fatorial de parcelas sub subdivididas com tratamentos adicionais (5x4x2+2). Os fatores foram: cinco plantas de cobertura, quatro épocas de dessecação, dois tratamentos de inoculação das sementes e duas testemunhas (TN = 90 Kg N ha-1 e T0 = sem N e sem inoculação). As variáveis analisadas nas plantas de cobertura foram massa seca (MS) e nitrogênio total (N-Total). No feijoeiro-comum avaliou-se teor de clorofila (TC), número de nódulos (NN), massa seca de nódulos (MSN), massa seca da parte aérea (MSPA), massa seca de raiz (MSR) e a produção de grãos (PG). Os resultados mostraram que o desempenho agronômico do feijoeiro-comum não foi afetado pelas épocas de dessecação das plantas de cobertura, embora a quantidade de N-Total acumulada pelas plantas de cobertura tenha sido influenciada pela época de semeadura. A inoculação do feijoeiro-comum promoveu aumento do NN e MSN, do TC e da MSPA do feijoeiro-comum. Em Santo Antônio de Goiás obteve-se maior PG do feijoeiro-comum em cultivo após braquiária brizanta, braquiária ruziziensis, milheto e pousio. | ABSTRACT The common bean requires high levels of nitrogen (N) to achieve high productivity, which can be supplied, at least partially, by the biological nitrogen fixation (BFN). Two field experiments were carried out in the winter season of 2015 aiming to evaluate the effects of different cover crops, desiccation times and the agronomic performance of the common bean inoculated with rhizobia. The experiments were assembled in a randomized block design with four replications, in a factorial split-plot arrangement with two additional treatments (5x4x2+2). The factors were composed of five cover crops, four desiccation times, two seed inoculation treatments and two additional controls (TN = 90 Kg N ha-1 and T0 = without N and without inoculation). The variables analyzed in the cover crops were dry mass (DM) and total nitrogen (Total-N). With the common bean, the chlorophyll content (CC), the number of nodules (NN), the nodule dry weight (NDW), the shoot dry weight (SDW), the root dry weight (RDW) and the grain yield (GY) were evaluated. The results showed that the agronomic performance of the common bean was not affected by the desiccation times of the cover crops, although the amount of Total-N accumulated by cover crops was influenced by sowing times. Inoculation of the common bean promoted an increase in the NN, NDW, CC and SDW. Higher GY of the common bean was achieved with its cropping after Brachiaria brizantha, Brachiaria ruziziensis, millet and fallow.

The common bean requires high levels of nitrogen (N) to achieve high productivity, which can be supplied, at least partially, by the biological nitrogen fixation (BFN). Two field experiments were carried out in the winter season of 2015 aiming to evaluate the effects of different cover crops, desiccation times and the agronomic performance of the common bean inoculated with rhizobia. The experiments were assembled in a randomized block design with four replications, in a factorial split-plot arrangement with two additional treatments (5x4x2+2). The factors were composed of five cover crops, four desiccation times, two seed inoculation treatments and two additional controls (TN = 90 Kg N ha-1 and T0 = without N and without inoculation). The variables analyzed in the cover crops were dry mass (DM) and total nitrogen (Total-N). With the common bean, the chlorophyll content (CC), the number of nodules (NN), the nodule dry weight (NDW), the shoot dry weight (SDW), the root dry weight (RDW) and the grain yield (GY) were evaluated. The results showed that the agronomic performance of the common bean was not affected by the desiccation times of the cover crops, although the amount of Total-N accumulated by cover crops was influenced by sowing times. Inoculation of the common bean promoted an increase in the NN, NDW, CC and SDW. Higher GY of the common bean was achieved with its cropping after Brachiaria brizantha, Brachiaria ruziziensis, millet and fallow.

RESUMO O objetivo do trabalho foi avaliar o efeito da densidade de plantas na fileira e de doses de nitrogênio (N) em cobertura na nutrição e desempenho produtivo das cultivares de feijão comum IPR 139 e Pérola. Para cada cultivar, o delineamento experimental utilizado foi em blocos ao acaso, em parcelas subdivididas e três repetições. As parcelas consistiram de três densidades de plantas (5, 7 e 9 plantas m-1 de fileira) e as subparcelas de cinco doses de N (0, 30, 60, 120 e 180 kg ha -1). Foram avaliadas: matéria seca da parte aérea, teores de macro e micronutrientes na folha diagnose, componentes da produção, produtividade de grãos e teor de proteína nos grãos. Menores densidades de plantas (5 e 7 plantas m-1) proporcionaram maior produção de MS e número de vagens por planta e não reduziram a produtividade de grãos. Na ausência da adubação nitrogenada, a redução da densidade de plantas diminuiu o teor de N nas folhas do feijoeiro. A adubação nitrogenada aumentou linearmente a produção de matéria seca e o teor de N nas folhas do feijoeiro, principalmente sob as menores densidades de plantas. Independentemente da densidade de plantas, o fornecimento de N aumentou linearmente a produtividade de grãos das cultivares IPR 139 e Pérola em 17,3 e 52,2%, respectivamente. | ABSTRACT The objective of this work was to evaluate the effect of plant densities and sidedressed nitrogen (N) rates on nutrition and productive performance of the common bean cultivars IPR 139 and Pérola. For each cultivar, a randomized complete block experimental design was used in a split-plot arrangement, with three replicates. Plots consisted of three plant densities (5, 7, and 9 plants ha-1) and subplots of five N rates (0, 30, 60, 120, and 180 kg ha-1). Aboveground dry matter, leaf macro- and micronutrient concentrations, yield components, grain yield, and protein concentration in grains were evaluated. Lower plant densities (5 and 7 plants m-1) increased aboveground dry matter production and the number of pods per plant and did not reduce grain yield. In the absence of N fertilization, reduction of plant density decreased N concentration in common bean leaves. Nitrogen fertilization linearly increased dry matter and leaf N concentration, mainly at lower plant densities. Regardless of plant density, the N supply linearly increased grain yield of cultivars IPR 139 and Pérola by 17.3 and 52.2%, respectively.

The objective of this work was to evaluate the effect of plant densities and sidedressed nitrogen (N) rates on nutrition and productive performance of the common bean cultivars IPR 139 and Pérola. For each cultivar, a randomized complete block experimental design was used in a split-plot arrangement, with three replicates. Plots consisted of three plant densities (5, 7, and 9 plants ha-1) and subplots of five N rates (0, 30, 60, 120, and 180 kg ha-1). Aboveground dry matter, leaf macro- and micronutrient concentrations, yield components, grain yield, and protein concentration in grains were evaluated. Lower plant densities (5 and 7 plants m-1) increased aboveground dry matter production and the number of pods per plant and did not reduce grain yield. In the absence of N fertilization, reduction of plant density decreased N concentration in common bean leaves. Nitrogen fertilization linearly increased dry matter and leaf N concentration, mainly at lower plant densities. Regardless of plant density, the N supply linearly increased grain yield of cultivars IPR 139 and Pérola by 17.3 and 52.2%, respectively.

RESUMO A interferência causada pelas plantas daninhas é um dos fatores que limitam a produtividade do feijoeiro e dentre essas destaca-se o picão-preto como uma das principais espécies que competem com a cultura pelos recursos do meio. Assim sendo, objetivou-se com este trabalho, avaliar a habilidade competitiva de cultivares de feijão do tipo preto (BRS Campeiro, IPR Uirapuru, SCS204 Predileto e BRS Supremo) na presença de biótipo de picão-preto. O delineamento utilizado foi o de blocos casualizados, com quatro repetições. Os tratamentos foram arranjados em série substitutiva e constituíram-se de proporções da cultura e de picão-preto: 100:0; 75:25; 50:50: 24:75 e 0:100, o que corresponde a 40:0, 30:10, 20:20, 10:30 e 0:40 plantas vaso-1. A análise da competitividade foi efetuada por meio de diagramas aplicados a experimentos substitutivos, mais uso de índices de competitividade relativa. Avaliou-se a área foliar e a massa seca da parte aérea aos 40 dias após a emergência das espécies. Houve competição pelos mesmos recursos do meio entre as cultivares de feijão e o picão-preto, ocasionando interferência negativa no crescimento das espécies, independentemente da proporção de plantas. As cultivares de feijão apresentaram menor perda relativa ao reduzirem as variáveis morfológicas do picão-preto e demonstram possuir superioridade na habilidade competitiva em relação à planta daninha. A competição interespecífica é menos prejudicial para ambas as espécies envolvidas do que a competição intraespecífica. | ABSTRACT Weed interference is a factor that limits the productivity of beans and, among these, hairy beggarticks is one of the main species competing with the crop for environmental resources. Thus, the aim of this study is to evaluate the competitive ability of black bean cultivars (BRS Campeiro, IPR Uirapuru, SCS204 Predileto and BRS Supremo) in the presence of a biotype of hairy beggarticks. The experimental design is a completely randomized block with four replications. Treatments were arranged in a replacement series, consisting of a proportion of the crop and the hairy beggarticks: 100:0; 75:25; 50:50: 24:75, and 0:100, which corresponds to 40:0, 30:10, 20:20, 10:30, and 0:40 plant pots1. We accomplished competitive analysis through diagrams applied to the replacement series, as well as using relative competitive indices. The leaf area and shoot dry mass were evaluated at 40 days after emergence of the species. There was competition between bean cultivars and hairy beggarticks for the same environmental resources, causing negative interference in the growth of the species, independent of the proportion of plants. Bean cultivars had a lower relative loss by reducing the morphological variables of the hairy beggarticks, thereby demonstrating superiority in its competitive ability in relation to the weed. Interspecific competition is less damaging than intraspecific competition for both species.

Weed interference is a factor that limits the productivity of beans and, among these, hairy beggarticks is one of the main species competing with the crop for environmental resources. Thus, the aim of this study is to evaluate the competitive ability of black bean cultivars (BRS Campeiro, IPR Uirapuru, SCS204 Predileto and BRS Supremo) in the presence of a biotype of hairy beggarticks. The experimental design is a completely randomized block with four replications. Treatments were arranged in a replacement series, consisting of a proportion of the crop and the hairy beggarticks: 100:0; 75:25; 50:50: 24:75, and 0:100, which corresponds to 40:0, 30:10, 20:20, 10:30, and 0:40 plant pots1. We accomplished competitive analysis through diagrams applied to the replacement series, as well as using relative competitive indices. The leaf area and shoot dry mass were evaluated at 40 days after emergence of the species. There was competition between bean cultivars and hairy beggarticks for the same environmental resources, causing negative interference in the growth of the species, independent of the proportion of plants. Bean cultivars had a lower relative loss by reducing the morphological variables of the hairy beggarticks, thereby demonstrating superiority in its competitive ability in relation to the weed. Interspecific competition is less damaging than intraspecific competition for both species.