scholarly journals ACÚMULO DE MASSA SECA E MACRONUTRIENTES PELO SORGO SACARINO EM DIFERENTES NÍVEIS DE ADUBAÇÃO NPK

2019 ◽  
Vol 18 (1) ◽  
pp. 1-13
Author(s):  
FLAVIA CRISTINA DOS SANTOS ◽  
LEANDRO FLÁVIO CARNEIRO ◽  
MANOEL RICARDO DE ALBUQUERQUE FILHO ◽  
MÔNICA MATOSO CAMPANHA ◽  
MARIA LÚCIA FERREIRA SIMEONE ◽  
...  

RESUMO – Com o objetivo de determinar o acúmulo de massa seca e macronutrientes ao longo do ciclo do sorgosacarino BRS 506, em diferentes níveis de adubação NPK, foram instalados experimentos por dois anos, em Latossolo,sob irrigação. Utilizou-se o delineamento experimental de blocos ao acaso, com quatro repetições. Os tratamentosforam de quatro níveis tecnológicos, relacionados à adubação N-P2O5-K2O, em kg ha-1: muito baixo (NPK = 0-0-0);baixo (NPK = 80-50-80); médio (NPK = 160-100-160) e alto (NPK = 240-150-240). Avaliaram-se o acúmulo demassa seca e macronutrientes aos 30, 50, 70, 90 e 110 dias após plantio (DAP). No geral, foram ajustados modelospolinomiais de segundo grau. O acúmulo de massa seca e macronutrientes apresentou taxa inicial baixa, até cerca de30 DAP, e a partir daí aumentou consideravelmente, até próximo à maturação, para então se estabilizar e decrescer.No geral, o acúmulo de massa seca foi maior no nível tecnológico alto e o acúmulo de nutrientes não diferiu entre osníveis médio e alto, sendo menor para os níveis baixo e muito baixo. Recomendam-se 160-100-160 kg ha-1 de N-P2O5-K2O para produtividade satisfatória do sorgo sacarino e manutenção da fertilidade do solo, além de outras práticas quefavoreçam a ciclagem de nutrientes.Palavras-chave: Sorghum bicolor (L.) Moench, nutrição, fertilização, absorção de nutrientes.DRY MASS AND MACRONUTRIENTS ACCUMULATION OF SWEET SORGHUMIN DIFFERENT LEVELS OF NPK FERTILIZATIONABSTRACT – In order to determine the dry mass and macronutrients accumulation along the sweet sorghum BRS 506cycle, at different levels of NPK fertilization, experiments were carried out for two years in Oxisol, under irrigation.The experimental design was a randomized complete block with four replicates. The treatments comprised fourlevels of soil fertility, related to N-P2O5K2O fertilization, in kg ha-1: very low (NPK = 0-0-0); low (NPK = 80-50-80);medium (NPK = 160-100-160) and high (NPK = 240-150-240). Dry matter accumulation and macronutrients wereevaluated at 30, 50, 70, 90 and 110 days after planting (DAP). In general, polynomial models of the second degree wereadjusted. Dry matter and macronutrient accumulation presented a low initial rate, until 30 DAP, from there it increasedconsiderably until near the maturation, then stabilizing and decreasing. In general, dry mass accumulation was higherat high technological level and nutrient accumulation did not differ between medium and high levels, being lower forlow and very low levels. It is recommended to apply 160-100-160 kg ha-1 of N-P2O5-K2O for a satisfactory productivityof sorghum and maintenance of soil fertility, in addition to other practices favoring the nutrients cycling.Keywords: Sorghum bicolor (L.) Moench, nutrition, fertilization, nutrient uptake.

2009 ◽  
Vol 33 (4) ◽  
pp. 985-992
Author(s):  
Juliano Ribeiro Araújo ◽  
Magno Antonio Patto Ramalho ◽  
Adriano Teodoro Bruzi ◽  
Ângela de Fátima Barbosa Abreu

The objective of this study was to verify the response of dry matter accumulation in bean lines (Phaseolus vulgaris L.) to different levels of nitrogen fertilizers. Six genotypes ('BRSMG Majestoso', 'Pérola', MA-I-18.13, 'Ouro Negro', 'BRSMG Talismã', and MA-I-2.5) were evaluated in Lavras, testing three N levels (0, 60, and 120 kg/ha) and using ammonium sulphate as N source. The experimental design adopted was the randomized block design in a 6 x 3 factorial structure with three replications and the plots were composed of five 5-m rows. The seeds were sown in November 2005 and July 2006. Total dry mass of five competitive plants was evaluated after 35 days from sowing, harvested from a pre-determined place in the useful area of the plots. This process was repeated every ten days until the harvest. The grain yield was also evaluated in one of the rows of the useful area of the plots. It was observed that regarding the dry mass accumulation, the genotypes did not present different responses at the N levels and the average increase per kg/ha applied N was 6.75 kg/ha grains. The genotype BRSMG Majestoso is the most responsive, with 14.4 kg/ha grains per kg applied N whereas the most tolerant is the MA-I-2.5 with1.8 kg/ha grains per kg N.


2004 ◽  
Vol 61 (5) ◽  
pp. 496-500 ◽  
Author(s):  
Anacleto Ranulfo dos Santos ◽  
Waldssimiler Teixeira de Mattos ◽  
Ana Aparecida da Silva Almeida ◽  
Francisco Antonio Monteiro ◽  
Beatriz Dias Corrêa ◽  
...  

Alfalfa cultivar Crioula (Medicago sativa cv. Crioula) is grown in South Brazil and only a few studies on the plants' boron requirement are available. A greenhouse experiment was carried out with alfalfa to measure boron acquisition, production and distribution in the plant; data on critical level and production potentials were recorded. Plants were grown in ground quartz added with 1 L of solution, with the following boron rates: 0, 0.0625, 0.125, 0.25, 0.50, 1.00, and 2.00 mg L-1. Plants were harvested at 46 days of growth. Forage dry mass was increased by boron supply and dry matter accumulation was considerably low in control. Boron concentration in the leaves was higher than in the stems or roots. Boron utilization from the external solution reached 90% at 0.0625 mg L-1 and sharply decreased with further increasing boron rates. Boron concentration and content in the leaves and in plant tops were at maximum when applied boron was between 1.5 and 1.6 mg L-1. Critical levels of boron in plant were 61 mg kg-1 in the leaves and 39 mg kg-1 in plant tops for this cultivar of alfalfa.


2018 ◽  
Vol 17 (1) ◽  
pp. 15
Author(s):  
IRAN DIAS BORGES ◽  
ELAINE CRISTINA TEIXEIRA ◽  
LORENA MARTINS BRANDÃO ◽  
ANTÔNIO AUGUSTO NOGUEIRA FRANCO ◽  
MARCOS KOITI KONDO ◽  
...  

ABSTRACT - The present study aimed to determine the curves of macronutrients and dry matter accumulation in grain sorghum DKB 599, grown in a semiarid region. A field experiment was conducted on a sandy loam eutrophic red Latosol (Oxisol) in Janaúba, State of Minas Gerais (MG), Brazil, in a randomized block design with four replications. As statistical method, a nonlinear regression, sigmoidal function with three parameters was used. After drying, the plants were weighed and ground to determine N, P, K, Ca, Mg and S concentration. Grain sorghum plants accumulate nutrients in their shoots in the following order: N> K> Ca> P> Mg> S. The highest concentrations of K and N were observed in stems and grains, respectively. In the conditions of this experiment, the most favorable time to perform nitrogen and potassium topdressing fertilization is when the plants present seven fully expanded leaves or 24 days after the emergency (DAE). Keywords: fertilization, growth, nutrition, Sorghum bicolor. ABSORÇÃO DE MACRONUTRIENTES E ACÚMULO DE MATÉRIA SECA NO SORGO GRANÍFERO RESUMO - Este trabalho teve como objetivo determinar as curvas de acúmulo de matéria seca e macronutrientes no sorgo DKB 599 cultivado em região semiárida. O experimento foi conduzido em campo sobre um Latossolo Vermelho eutrófico, de textura franco-argilosa, no município de Janaúba-MG, Brasil, em delineamento experimental de blocos casualizados, com quatro repetições. Utilizou-se o modelo de regressão não linear, função sigmoidal com três parâmetros como método estatístico. Após secagem, cada parte da planta foi pesada e moída para, em seguida, determinarem-se os teores de N, P, K, Ca, Mg e S. As plantas de sorgo granífero acumulam nutrientes em sua parte aérea na seguinte ordem: N > K > Ca > P > Mg > S. As maiores concentrações de K e N foram observadas, respectivamente, nos caules e nos grãos. Nas condições de condução do experimento, a época mais propícia para realizar a adubação nitrogenada e potássica em cobertura é quando as plantas apresentam sete folhas totalmente expandidas ou 24 dias após a emergência (DAE). Palavras-chave: fertilização, crescimento, nutrição, Sorghum bicolor.


2012 ◽  
Vol 22 (2) ◽  
pp. 97-111 ◽  
Author(s):  
Hector E. Pérez ◽  
Lisa M. Hill ◽  
Christina Walters

AbstractAssessments of seed storage physiology among Arecaceae (palm) species are often inconclusive because seeds exhibit diverse responses to low temperature and moisture conditions. Interrelationships between dry matter accumulation, cell structure and water relations during seed development of the endangered Hawaiian endemic palm, Pritchardia remota, suggest that damage from drying results from mechanical strain. Endosperm and fruits accumulate dry mass through most of the 400 d gestation period, but embryos reached maximum dry mass about 250 d post-anthesis (DPA). Mostly sucrose and some triacylglycerols accumulated in the cytoplasm and vacuoles of embryo cells, and organelles in mature embryo cells de-differentiated. Water content and water potential decreased as embryos matured and embryos contained about 0.45 g H2O (g dry mass)− 1 ( − 26 MPa) at shedding. Mature embryos survived drying to 0.16 g g− 1 ( − 49 MPa), but further drying was lethal. A model of allowable cell shrinkage is consistent with the substantial, but incomplete, desiccation tolerance acquired in P. remota embryos, and provides a new framework to explain variation in critical water contents as embryos develop. We suggest that desiccation tolerance, which distinguishes recalcitrant and orthodox physiologies among seeds, can be quantified by mechanical strain when embryo cells shrink during drying.


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