Consulta: creatorFacets:"Araujo,Leandro Coelho de"
Registros recuperados: 7
Data/hora: 10/06/2024 17:17:39

Modelos empíricos para estimar o acúmulo de matéria seca de capim-marandu com variáveis agrometeorológicas
Provedor de dados: Pesquisa Agropecuária Brasileira
Autores: Cruz,Pedro Gomes da; Santos,Patricia Menezes; Pezzopane,José Ricardo Macedo; Oliveira,Patrícia Perondi Anchão; Araujo,Leandro Coelho de.
O objetivo deste estudo foi testar modelos empíricos de regressão linear, para a predição do acúmulo de matéria seca (TAMS) de Urochloa brizantha cv. Marandu, em função de variáveis agrometeorológicas. Para gerar os modelos, foi utilizada a taxa média de acúmulo de matéria seca, em condições de sequeiro, entre 1998 e 2002. As variáveis avaliadas foram: temperaturas mínima, máxima e média, radiação global (Rg), graus-dia, evapotranspiração real (ETR) e potencial (ETP) obtidas a partir do balanço hídrico, unidades fototérmicas (UF) e índice climático de crescimento (ICC). As regressões univariada e multivariada mostraram boa capacidade de predição, com exceção para as que utilizam a UF. Os melhores resultados foram para a regressão multivariada, com Tmín, Rg...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brachiaria brizantha; Urochloa brizantha; Regressão linear; Regressão multivariada.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2011000700001

Dry matter production of Tanzania grass as a function of agrometeorological variables
Provedor de dados: Pesquisa Agropecuária Brasileira
Autores: Pezzopane,José Ricardo Macedo; Santos,Patricia Menezes; Mendonça,Fernando Campos; Araujo,Leandro Coelho de; Cruz,Pedro Gomes da.
The objective of this work was to develop and validate linear regression models to estimate the production of dry matter by Tanzania grass (Megathyrsus maximus, cultivar Tanzania) as a function of agrometeorological variables. For this purpose, data on the growth of this forage grass from 2000 to 2005, under dry‑field conditions in São Carlos, SP, Brazil, were correlated to the following climatic parameters: minimum and mean temperatures, degree‑days, and potential and actual evapotranspiration. Simple linear regressions were performed between agrometeorological variables (independent) and the dry matter accumulation rate (dependent). The estimates were validated with independent data obtained in São Carlos and Piracicaba, SP, Brazil. The best statistical...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Panicum maximum; Climatic growth index; Degree‑days; Evapotranspiration; Modeling.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012000400001

Critical periods of sorghum and palisadegrass in intercropped cultivation for climatic risk zoning
Provedor de dados: Revista Brasileira de Zootecnia
Autores: Lima,Nino Rodrigo Cabral de Barros; Santos,Patricia Menezes; Mendonça,Fernando Campos; Araujo,Leandro Coelho de.
The objective of this work was to define critical periods for sorghum and palisadegrass cultivated on crop-livestock integrated systems under water deficit. An experiment was carried out in a completely random block design with four treatments (control and interruption of water supply in three periods) and three replicates. Water supply was interrupted until soil water humidity was close to permanent wilting point at the phases: germination of palisadegrass seeds; start of tillering of palisadegrass and initiation of panicles of shorghum; start of shorghum flowering. Water deficit starting at palisadegrass germination delayed intital development of the plants because of the reduction in tillering. Water restriction at panicle initiation phase and at...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Abiotic stress; Brachiaria brizantha; Crop-livestock integrated systems; Drought.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000700008

Response mechanisms of Brachiaria brizantha cultivars to water deficit stress
Provedor de dados: Revista Brasileira de Zootecnia
Autores: Santos,Patricia Menezes; Cruz,Pedro Gomes da; Araujo,Leandro Coelho de; Pezzopane,José Ricardo Macedo; Valle,Cacilda Borges do; Pezzopane,Cristiana de Gaspari.
Two cultivars of Brachiaria brizantha (Hochst ex. A. Rich) Stapf. (Syn. Urochloa) were evaluated for their adaptation to water deficit and the stress response mechanisms in a greenhouse experiment. The experimental design was in completely randomized blocks with a 2 × 2 × 4 factorial arrangement. The Marandu and BRS Piatã cultivars were evaluated under two water availability conditions, with or without water restriction. The harvests were carried out 0, 7, 14 and 28 days after the start of water restriction. For both cultivars, the water deficit stress caused a reduction in shoot biomass and leaf area and an increase in the percentage of roots in the deeper soil layers. The B. brizantha cv. Marandu reached critical levels of leaf water potential in a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: BRS Piatã; Marandu; Osmotic potential; Water availability; Water potential.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013001100001

Establishment of Brachiaria brizantha cv. Marandu, under levels of soil water availability in stages of growth of the plants
Provedor de dados: Revista Brasileira de Zootecnia
Autores: Araujo,Leandro Coelho de; Santos,Patrícia Menezes; Mendonça,Fernando Campos; Mourão,Gerson Barreto.
The objective of this work was to evaluate yield traits and development of palisadegrass under the influence of water deficit during the establishment period. The experiment was carried out in a greenhouse, in a completely random block statistical design in a factorial arrangement and additional treatment (3 × 3 + 1). The treatments referred to the suppression of irrigation at different phases of the establishment (sowing, germination and initial tillerring) until the soil presented water content of 75%, 50%, and 25% of the moisture related to field capacity (qFC), besides control treatment with no water restriction. Evaluations of number of grown tillers per vase, green leaves per tiller and plant height were carried out weekly, for five weeks after the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biomass; Drought; Palisadegrass; Tillering; Water deficit.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000700002

Development of maize and palisadegrass plants cultivated in intercrop under water deficit
Provedor de dados: Revista Brasileira de Zootecnia
Autores: Araujo,Leandro Coelho de; Santos,Patrícia Menezes; Mendonça,Fernando Campos; Lima,Nino Rodrigo Cabral de Barros.
The objective of this work was to evaluate the development and productive traits of palisadegrass single cultivated or intercropped with corn, in addition to corn intercropped with pasture, under water deficit at different development stages of the plants. It was used a complete block experimental design with split plots and three replicates. Periods of water deficit were placed in the plots and types of cultivation were placed in the subplots. Irrigation was stopped at germination and initial tillering of palisadegrass and at V4 and V15 stages of corn and returned when soil moisture was 40% of available water capacity. Tiller density and palisadegrass height were evaluated weekly. Dry matter (DM) of fractions of herbage mass as well as leaf area of the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brachiaria brizantha; Integration; Tiller; Zea mays.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000700001

Key factors that influence for seasonal production of Guinea grass
Provedor de dados: Scientia Agricola
Autores: Araujo,Leandro Coelho de; Santos,Patricia Menezes; Rodriguez,Daniel; Pezzopane,José Ricardo Macedo.
ABSTRACT: Climate, soil and management are the main drives for growth and production of tropical pastures. Thus, a better understanding of the effects of these factors and their interactions under climate conditions is required to obtain effective management options. Here, we used data from two field trials to research on climate and management interactions on the production seasonality of Panicum maximum Jacq. Treatments included four sampling times (250, 500, 750, and 1000 °C accumulated) during eight regrowth period, under irrigated and rainfed conditions and, cuts were made to simulate grazing intensity. All treatments were arranged in a completely randomized block design with four replications. At each sampling time, basal tillers were sampled to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Daylength; Degree-days; Mombaça; Tropical forage; Water deficit.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162018000300191