Instituto de Ciências Agrárias – CRP
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11787
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Resultados da Pesquisa
Item Foliar indices for carrot crop using the compositional nutrient diagnosis method(Pesquisa Agropecuária Tropical, 2017-10) Reis, Marcelo Rodrigues dos; Aquino, Leonardo Angelo de; Silva, Frederico Dellano Souza; Silva, Natalia Oliveira; Oliveira, Thaísa FernandaCarrot has a high yield potential, which requires an adequate and adaptable nutritional management, according to the needs and demands of each crop. Foliar diagnosis is a tool for adjustment and constant improvement of crop fertilization programs. This study aimed to determine leaf indices and reference values using the compositional nutrient diagnosis (CND) method, at three phenological stages of carrot crops [40 and 70 days after sowing (DAS) and at harvest]. In order to calculate the CND method, a database was created with leaf contents of the nutrients N, P, K, Ca, Mg, S, B, Cu, Mn and Zn and root yields, in commercial carrot crops. The nutrient limitation order was generated according to the fertilization response potential. At 70 DAS and at harvest, Mg and Mn were the most limiting nutrients by deficiency, while Zn was the most limiting by excess at 70 DAS, and P and Ca were the most limiting by excess at harvest. The results indicate that the foliar diagnosis performed with the CND method is only effective for the correction of nutritional disturbances in subsequent crops.Item Parcelamento de fósforo em algodoeiro irrigado(Pesquisa Agropecuária Tropical, 2012-01) Aquino, Leonardo Angelo de; Berger, Paulo Geraldo; Neves, Júlio César Lima; Lima, Tricia Costa; Aquino, Rosiane Filomena Batista Almeida deA maioria das regiões de cultivo de algodoeiro no Brasil apresenta baixa fertilidade dos solos, especialmente com relação ao fósforo (P) disponível. Objetivou-se avaliar a aplicação parcelada de doses de P em algodoeiro irrigado, visando a uma maior eficiência da adubação fosfatada, em comparação com a aplicação tradicional, em semeadura. O experimento foi desenvolvido em Neossolo Quartzarênico com 22 mg dm-3 de P (disponibilidade média), no norte de Minas Gerais. Utilizou-se delineamento em blocos ao acaso, em arranjo fatorial (4x3) + 3, com três repetições. Os fatores estudados foram doses de P2O5 (0 kg ha-1, 30 kg ha-1, 60 kg ha-1, 120 kg ha-1 e 180 kg ha-1) e três formas de aplicação parcelada (80% e 20%; 60% e 40%; 40% e 60% da dose do fertilizante aplicada em semeadura e aos 35 dias após a emergência (DAE), respectivamente), além da aplicação de 0 kg ha-1, 60 kg ha-1 e 120 kg ha-1 de P2O5 na semeadura. A fonte de P foi o superfosfato triplo granulado e houve aumento no conteúdo de P, na parte aérea, em função das doses aplicadas. Os teores de nutrientes na folha índice, exceto P, não foram influenciados pelas doses de P e pelos parcelamentos. O teor de P na folha índice e o número de capulhos por planta aumentaram com o incremento das doses de P, mas não foram influenciados pelo parcelamento do fertilizante fosfatado. A aplicação de 40% da dose de P em semeadura e do restante parcelado aos 35 DAE reduziu a produtividade de algodão em caroço, não havendo efeito significativo nos demais parcelamentos.Item DRIS indices in three phenological stages of the carrot crop(Pesquisa Agropecuária Tropical, 2017-02) Gonçalves, Felipe Augusto Reis; Aquino, Leonardo Angelo de; Dezordi, Luciel Rauni; Clemente, Junia Maria; Novais, Roberto FerreiraCarrot is one of the most consumed vegetables in Brazil, where the cultivars currently grown present a high yield potential and nutritional demand, which require constant adjustments in fertilization programs for the crop. This study aimed at determining reference values and diagnostic indices by using the DRIS method in three phenological stages of the carrot crop (around 40 and 70 days after sowing and at harvest), as well as evaluating the possibility of early diagnosis for nutritional limitations. For determining the DRIS norms, a database was obtained from leaf samplings, root yields and leaf contents of N, P, K, Ca, Mg, S, B, Cu, Mn and Zn, in carrot commercial fields. The nutritional limitation order was generated as a function of the fertilization response and optimum range of leaf contents. The reference values for K, Ca, Mg, S and Mn were similar in all sampling times. N, P, B, Cu and Zn varied with the stages sampled, indicating the need to standardize the sampling times for these nutrients. Mn, K and Mg were the most limiting nutrients for the crop growth, while Zn and B were the least limiting. There was a correlation between the diagnoses performed at early stages and those performed at harvest for K, Ca, Mg, S and Mn, indicating the possibility of early diagnosis for the deficiency of these nutrients.Item Effects of growth regulator and nitrogen on yield and lodging of irrigated wheat(Semina: Ciências Agrárias, 2016-05-10) Nunes, Pedro Henrique Marques Paula; Aquino, Leonardo Angelo de; Xavier, Felipe Oliveira; Santos, Luiz Paulo Dornelas dos; Machado, Lucas Gonçalves; Aquino, Priscila Maria deHigh rates of nitrogen (N) increase plant growth, which can result in lodging. To avoid excessive growth of plants, plant growth regulators (PGRs), which cause internode length reduction, can be used. In this study, our objective was to evaluate the N nutritional status, growth, and yield of irrigated wheat as parameters using variable rates of nitrogen and growth regulator. Two experiments were conducted in Rio Paranaíba – MG in 2011 and 2012 using the BRS 264 cultivar. The treatments consisted of two concentrations of N (50 and 110 kg ha^ -1 as urea) and five concentrations of the growth regulator trinexapac-ethyl (0, 0.2, 0.4, 0.6, and 0.8 L ha^ -1 of Moddus ® containing 25% w/v of trinexapac-ethyl). Each plot consisted of 20 rows of wheat spaced 0.17 m, six meters in length. We evaluated plant height, shoot dry matter accumulation, thousand-grain weight, number of grains per spike, yield, leaf N content in the index leaf and grain, amount of N uptake and export, and lodging index. The PGR resulted in a linear decrease in plant height and shoot dry matter production. However, the rates of the growth regulator did not affect productivity. The rates of N influenced the yield only in 2011.Item Estimativa da área foliar do girassol por método não destrutivo(Bragantia, 2011-03-14) Aquino, Leonardo Angelo de; Santos Júnior, Valdeir Celestino dos; Guerra, João Victor Santos; Costa, Marileide MoreiraMétodos de fácil execução, rápidos e não destrutivos, que possibilitem estimar a área foliar com precisão, são importantes para avaliar o crescimento das plantas nas condições de campo. Objetivou-se no presente trabalho, ajustar equações para estimar a área do limbo foliar e a área das folhas do girassol, em função das medidas lineares do limbo e do número de folhas por planta, incluindo a verificação da possibilidade de modelos comuns para as cultivares BR-122 e M-734. Seis plantas de cada cultivar nos estádios de início de florescimento e de florescimento pleno foram coletadas. As áreas dos limbos foliares foram determinadas por método direto. Foram medidos o comprimento ao longo da nervura principal e a largura de forma perpendicular à inserção do limbo no pecíolo. Foram ajustados os modelos linear, quadrático, cúbico, exponencial e potencial. Os modelos potenciais Ŷi = 1,6329Xi1,7164 e Ŷi = 0,5405Xi1,0212 com a utilização, respectivamente, das medidas da largura e do produto largura e comprimento são os mais adequados para estimar a área do limbo foliar do girassol. O modelo Ŷi = 5,1014Xi2,4383 permite estimar com precisão a área foliar total do girassol em função do número de folhas por planta. A precisão das equações ajustadas para as estimativas da área do limbo foliar ou de folhas por planta não é reduzida quando se ajustam modelos comuns às cultivares BR-122 e M-734.Item Diagnostic methods to assess the nutritional status of the carrot crop(Revista Brasileira de Ciência do Solo, 2015-09-25) Dezordi, Luciel Rauni; Aquino, Leonardo Angelo de; Aquino, Rosiane Filomena Batista de Almeida; Clemente, Junia Maria; Assunção, Natália SilvaLeaf analysis may identify nutrient deficiency or excess in plant tissue. The aim of this study was to determine reference values and generate nutritional diagnosis from the results of leaf analysis of the carrot crop (Daucus carota L.) by the methods of Critical Level, Sufficiency Range, Diagnosis and Recommendation Integrated System, and Compositional Nutrient Diagnosis. Contents of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn were determined in 210 carrot fields in the 2012 and 2013 crop seasons in the Alto Paranaíba region, MG, Brazil. The whole plant shoot was sampled at harvest time to generate reference values for diagnosis. The high yielding subpopulation showed yield higher than 87.8 Mg ha-1. The four diagnostic methods generated similar reference values of nutrients, but different from those found in the literature. Leaf diagnosis through nutrient content in the shoot at harvest time indicated Mn as the most limiting nutrient for growing carrot, followed by Mg, K, and Ca.Item Nutrient recommendation model for carrot crop – ferticalc carrot(Revista Brasileira de Ciência do Solo, 2015-08-18) Dezordi, Luciel Rauni; Aquino, Leonardo Angelo de; Novais, Roberto Ferreira; Aquino, Priscila Maria de; Santos, Luiz Paulo Dornelas dosThe literature on fertilization for carrot growing usually recommends nutrient application rates for yield expectations lower than the yields currently obtained. Moreover, the recommendation only considers the results of soil chemical analysis and does not include effects such as crop residues or variations in yield levels. The aim of this study was to propose a fertilizer recommendation system for carrot cultivation (FERTICALC Carrot) which includes consideration of the nutrient supply by crop residues, variation in intended yield, soil chemical properties, and the growing season (winter or summer). To obtain the data necessary for modeling nutritional requirements, 210 carrot production stands were sampled in the region of Alto Paranaíba, State of Minas Gerais, Brazil. The dry matter content of the roots, the coefficient of biological utilization of nutrients in the roots, and the nutrient harvest index for summer and winter crops were determined for these samples. To model the nutrient supply by the soil, the literature was surveyed in regard to this theme. A modeling system was developed for recommendation of macronutrients and B. For cationic micronutrients, the system only reports crop nutrient export and extraction. The FERTICALC which was developed proved to be efficient for fertilizer recommendation for carrot cultivation. Advantages in relation to official fertilizer recommendation tables are continuous variation of nutrient application rates in accordance with soil properties and in accordance with data regarding the extraction efficiency of modern, higher yielding cultivars.