ABSTRACT At poor conditions of nitrogen (N) in the soil, potato plants may accumulate starch leaves and be indicative N nutritional stress. The objective this work was to determine effects rates (0, 50, 100, 200 300 kg ha-1 N) on concentrations carbohydrates (total soluble sugars-TSS, reducing sugars-RS, non-reducing sugars-NRS starch) fourth leaf (FL) two cultivars (Asterix Atlantic) their critical levels (CL) associated fertilization rate necessary obtain maximum physical (MPE) economic...

Extreme temperatures and persistent water stress stand out among the main factors that restrict vegetative growth productivity of Coffea canephora. The objective this study was to evaluate orthotropic plagiotropic branches C. canephora under non-irrigated irrigated conditions, their correlation with climatic in Atlantic region Bahia State, Brazil. experiment established two treatments (non-irrigated irrigated) a completely random design 14 replicates. One four were labelled on each plant....

Unsustainable farming practices such as shifting cultivation and slash-and-burn agriculture in the humid tropics threaten preservation of rainforest health local global environment. In weathered soils prone to cohesion tropic due low Fe carbon content enormous amounts P that can be adsorbed, sustainable soil use is heavily dependent on availability efficient nutrients. This paper reviews literature field provides some insights about tropics, mainly for Brazilian Amazonia region. Careful...

Neste trabalho, objetivou-se avaliar o efeito de doses nitrogênio (N) sobre os teores carboidratos (açúcares solúveis totais, açúcares redutores e amido), matéria seca sólidos totais nos tubérculos quatro cultivares batata. Os originaram-se experimentos, realizados simultaneamente no campo, outono/inverno, na Universidade Federal Viçosa. Em todos foi utilizado delineamento em blocos casualizados, com repetições. tratamentos foram compostos cinco N (0, 50, 100, 200 300 kg ha-1) forma sulfato...

The amount of nutrients present in husks and beans from Conilon coffee fruits directly influence the crop nutritional management, as well its use a complement to conventional fertilization. study aimed quantify concentration accumulation husks, whole fruit irrigated non-irrigated plants cropped genotype C. canephora cv. Clone 02, clonal variety EMCAPA 8111. experiment consisted two treatments (irrigated non-irrigated) completely randomized design with 28 replicates under field conditions,...

Chlorophyll meter readings below a threshold value would indicate the necessity to supply nitrogen (N) crop. This study aimed determine values for chlorophyll (SPAD) and rate effects on SPAD leaf measurements of potato cultivars through crop cycle. Five N rates (0, 50, 100, 200, 300 kg ha−1) were evaluated in randomized block design, with four repetitions. index was measured oldest (OL) fourth from apex (FL) at 7, 14, 21, 28, 35, 49 days after emergence 90% plants plots. decreased plant age...

Leaf spraying of silicon (Si) depending on the source and concentration can biofortify tomato fruit by increasing content ascorbic acid firmness fruit. The objective this study was to determine whether foliar Si from different sources at several concentrations provided biofortified tomatoes evaluate their technological quality. experiment carried out in a greenhouse pot. treatments consisted four (monosilicic acid, potassium silicate, silicate sodium mixture, nanosilica) (0.0, 0.2, 0.4 0.6 g...

O café conilon (Coffea canephora) é uma cultura de grande importância na agricultura brasileira e ocupa posição destaque entre os produtos exportação.O cafeeiro pode ser conduzido em ambientes baixa luminosidade, pois apresenta irradiância saturação.O trabalho teve como objetivo avaliar o crescimento mudas diferentes níveis sombreamento a luz plena.O experimento foi realizado no CCA-UFES, Alegre/ES,

The objective of this study was to establish a nutrient sufficiency range and DRIS standards Conilon coffee grown in southern Bahia, Brazil for the pre-flowering grain-filling stages perform nutritional diagnosis these plants using different methods. collections were performed 24 farm fields leaf standards, 278 samples collected diagnosis. by criterion method. must be specific each phenological stage plants. concentrations calcium (Ca), sulfur (S), boron (B) higher stage; nitrogen (N),...

Objetivou-se avaliar a influência do nitrogênio (N) sobre leitura índice SPAD, verificar se as leituras SPAD na quarta folha são sensíveis variações com posição e o horário de avaliação bem como efeito da irrigação sob cultura batata. O experimento foi conduzido junho setembro 2008, no delineamento experimental blocos casualizados, quatro repetições. Os tratamentos constaram cinco doses N (0; 50; 100; 200 300 kg ha-1) aplicadas sulco em pré-plantio, forma sulfato amônio. As foram realizadas...

This work aimed to quantify the content and accumulation of macronutrients (N, P K) in dry biomass oats-black (Avena strigosa Schreb) soil (P K), recycled by after waste left successive fertilizations organic mineral carried out maize. The experiment was conducted at Experimental Field Coimbra, located city Coimbra / MG from Department Plant Science (DFT) Federal University Viçosa (UFV). planting agricultural year 2003/2004. treatments were: no fertilization, fertilization 150 kg ha-1...

The soil organic carbon (SOC) stock is an important attribute in the maintenance of ecosystem services by natural and agricultural ecosystems. In humid tropics, slash-and-burn cultivation for food production establishment pastures has frequently led to degradation. eastern Brazilian Amazonia, we assessed impacts different land-use systems on SOC some chemical properties soils. Four were studied: shifting (SC), pasture (PA), mixed fallow (MF) secondary forest (SF). soils studied, most...

Our objectives were to study characteristics of the fruit (weight, percentage husk/grain), determine concentration and accumulation nutrients in fruits, grain husk, verify existence genetic diversity Coffea canephora genotypes. The experiment was conducted with 20 genotypes a four-year-old plantation, randomized block design four replications five plants per plot. fruits oven-dried, depulped (husk separated from grain) sent laboratory for nutritional analysis. Macronutrients N K most...

Para a obtenção de bons resultados com uso da irrigação no cafeeiro, esta deve ser manejada forma adequada, disponibilizando água em quantidade suficiente para o desenvolvimento cultura.Assim, visando melhorar eficiência do água, polímeros hidroabsorventes têm sido utilizados intuito minimizar irregular disponibilidade cultura.Nesse sentido, objetivou-se neste trabalho, avaliar diferentes turnos rega e doses hidroabsorvente na fase

Adjusting nitrogen (N) fertilization rates to crop requirements optimizes N efficiency and reduces environmental pollution.In accordance with such precision agriculture, methods facilitating rapid simple real-time yield prognostication are desirable.The aims of this study establish a prognostic model for tuber yield; early characterization properly N-nourished plant determine the use by Asterix Atlantic potato cultivars.In two separate experiments, on each cultivar, five pre-planting (0, 50,...

Objetivou-se com este trabalho estabelecer modelos matemáticos mais apropriados para estimar a área foliar da cultivar de batata Atlantic, utilizando-se o comprimento (C) e largura (L) folha. As avaliações foram realizadas em 270 folhas coletadas aleatoriamente no campo produção Universidade Federal Viçosa, duas épocas, aos 21 50 dias após emergência das plantas. Em laboratório, mensurados folhas, além por um integrador foliar. Os dados obtidos submetidos à análise regressão, sendo AF...

The objective of this study was to evaluate the in vitro germination beetroot seeds, cv. Early Wonder Tall Top, treated with gibberellic acid and sucrose at different concentrations. A randomized complete block design a 2 x 5 factorial arrangement five replications used. seeds ware pre-soaked (GA3) destilated water during six hours, maintained concentration culture medium (0, 15, 30, 45, 60 g L-1). Seeds GA3 concentrations 15 L-1 presented highest germination, while seedlings vigor were...

Objetivou-se avaliar o efeito de doses nitrogênio (N) sobre os teores e exportações macro micronutrientes nos tubérculos cultivares batata das mais plantadas no Brasil. Os experimentos foram desenvolvidos na época outono/inverno, em solo Podzólico Vermelho-Amarelo Câmbico, textura argilosa. Foram instalados quatro experimentos, simultaneamente, campo. Em cada experimento avaliadas uma cultivar: Ágata, Asterix, Atlantic Monalisa cinco N: 0, 50, 100, 200 300 kg ha-1, forma sulfato amônio,...

Abstract The possible benefits of molybdenum (Mo)‐enriched seeds for grain legumes have yet to be addressed in sub‐humid tropical areas, where cowpea ( Vigna unguiculata L.) is an important crop. In 2016, with 0.014 (low), 0.674, or 1.987 (high) μg seed −1 Mo were harvested from plants sprayed 0, 250, 850 g ha –1 Mo, respectively. These combined either Bradyrhizobium inoculation (with without) 2017 nitrogen (0 60 kg ) 2018 and evaluated under small farmer management Maranhão State, Brazil....

Objetivou-se avaliar a viabilidade da produção de mudas tomateiro por estaquia em diferentes substratos.O experimento foi conduzido casa-de-vegetação no Centro Ciências Agrárias UFES, Alegre-ES