|
|
|
|
|
| Anjos,João Carlos Rocha dos; Andrade Júnior,Aderson Soares de; Bastos,Edson Alves; Noleto,Donavan Holanda; Melo,Francisco de Brito; Brito,Raimundo Rodrigues de. |
| Abstract: The objective of this work was to evaluate water storage in a Plinthaqualf under different straw levels during the fourth ratoon season of a sugarcane (Saccharum officinarum) crop. The study was conducted in the 2013/2014 crop season, with the cultivar SP-813250, at two soil depths (0.0-0.3 and 0.3-0.6 m), in a randomized complete block design, with five straw levels (0.0, 4.2, 9.5, 13.0, and 18.4 Mg ha-1) and four replicates. Soil moisture content was monitored with a time-domain reflectometer. The straw provided gains of up to 20 Mg ha-1 stems and kept increased water storage in the soil, in comparison with the soil without straw, in all evaluated periods. Maintenance of up to 50% (9.5 Mg ha-1) of sugarcane straw on soil surface promotes better... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Saccharum officinarum; No-tillage; Soil mulch; Water balance. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2017000600464 |
| |
|
|
| Melo,Francisco de Brito; Souza,Henrique Antunes de; Bastos,Edson Alves; Cardoso,Milton Jose. |
| ABSTRACT Proposing sufficiency ranges and critical levels is an important technique for correct evaluation of leaf nutrient diagnosis. In this study, the objective was to propose critical levels and sufficiency ranges of macro- and micronutrients for the diagnostic leaf of cowpea, collected at flowering, with the results of macro- and micronutrients and productivity in the Northeast of Brazil. The critical level was calculated by the reduced normal distribution and by the boundary line method, which was also used to generate sufficiency ranges. For the critical level by reduced normal distribution, the relationship of the nutrients with 90% of maximum productivity was adopted. For the boundary line, the relationship of the nutrients that are in the upper... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Vigna unguiculata; Leaf content; Plant nutrition. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902020000400407 |
| |
|
|
| Cardoso,Milton José; Bastos,Edson Alves; Athayde Sobrinho,Cândido; Melo,Francisco de Brito. |
| ABSTRACT Cowpea beans play an important role in Brazilian farming, mainly in northern and northeastern regions, where it is widely grown among smallholder farmers. In recent years, commercial farmers have expanded its cultivation, mostly to the Midwest. This study aimed at evaluating the planting density of 'BRS Itaim' black-eyed cowpea beans under conventional (CT) and no-tillage (NT), with 75% mulch in the first year. Two experiments (CT and NT) were conducted at Embrapa Meio-Norte in Teresina - PI (Brazil), during the 2014/2015 harvest. Both experiments were carried out in a randomized block design with four replicates, considering the planting densities (PD) 12, 16, 20, 24, and 28 plants m-2. In both systems, grain yields (GY) and the number of pods... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Yield components; Yield grain; Vigna unguiculata (L.) Walp. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902017000500856 |
| |
|
|
| Melo,Francisco de Brito; Corá,José Eduardo; Cardoso,Milton José. |
| Na cultura do milho (Zea mays L.), o suprimento inadequado de nitrogênio e a densidade de plantio são considerados fatores limitantes ao rendimento de grãos. Objetivou-se, neste trabalho, avaliar a influência de doses de nitrogênio e diferentes densidades de plantas nos componentes de produção e no rendimento da cultura de milho. O experimento foi instalado na Região de cerrado do sul do Maranhão, MA, em um Latossolo Vermelho-Amarelo distrófico, textura argilosa, cultivado há seis anos em sistema de plantio direto (SPD). O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições, e os tratamentos segundo o arranjo em um esquema fatorial 5 x 4. Os tratamentos foram constituídos pela combinação de cinco doses de nitrogênio, na... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Milho; Planta-efeito do Nitrogênio; Plantio direto. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902011000100004 |
| |
|
|
| Melo,Francisco de Brito; Cardoso,Milton José; Andrade Júnior,Aderson Soares de; Ribeiro,Valdenir Queiroz. |
| ABSTRACT Zinc (Zn) is an essential micronutrient for plants, due to its role as a functional, structural, or regulatory cofactor in a large number of enzymes. The element is necessary for the synthesis of tryptophan, which is a precursor of indoleacetic acid. The aim of this study was to evaluate the behavior of two cowpea cultivars fertilized with four doses of Zn (0.0, 2.0, 4.0, and 6.0 kg of Zn ha-1) regarding dry grain yield (PGS), in addition to quantifying leaf and grain Zn content and grain crude protein. The experiment was conducted in the town of Brejo, in the state of Maranhão, Brazil. A 4 x 2 factorial scheme was used with four replications. Response functions were adjusted by calculating the Zn doses which provided a maximum technical... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mineral nutrition; Vigna unguiculata (L.) Walp; Grain yield. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902017000500739 |
| |
|
|
| Silva,Cláudio Ricardo da; Andrade Júnior,Aderson Soares de; Alves Júnior,José; Souza,Antonio Barros de; Melo,Francisco de Brito; Coelho Filho,Maurício Antonio. |
| The use of capacitance sensors is one of the methods used to quantitatively measure soil water contents (theta, m³ m-3). Sensors provide readings at desired depths and time intervals. A capacitance probe (Diviner 2000) was calibrated for a Rhodic Paleudult from the Piaui State, Brazil. Six access tubes were installed in a 5 × 2 m grid arrangement. Three moisture levels (saturated, moist and dry) were used in two replications. Probe readings and soil samplings to determine theta were made at 0.1 m depth intervals down to a depth of 1.0 m. A power calibration equation was developed for each depth as well as for the entire soil profile (Root Mean Square Error = 0.014, R² = 0.93) for a theta range of 0.068 to 0.264 m³m-3. A separate calibration for each depth... |
| Tipo: Info:eu-repo/semantics/report |
Palavras-chave: FDR probe; Sensor; Irrigation; Soil water content. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162007000600012 |
| |
|
|
|
