scholarly journals Metodologias para monitoramento nutricional de gérbera cultivada em substrato

2015 ◽  
Vol 21 (1) ◽  
pp. 77
Author(s):  
Fernanda Ludwig ◽  
Dirceu Maximino Fernandes ◽  
Amaralina Celoto Guerrero ◽  
Roberto Lyra Villas Bôas
Keyword(s):  
Electrical Conductivity ◽  
Water Volume ◽  
Substrate Solution ◽  
Paulo State ◽  
Nutritional Analysis ◽  
Periodic Monitoring ◽  
Nutritional Monitoring ◽  
Non Destructive ◽  
Linear Correlations ◽  
Sample Dilution

This study aimed to assess methodologies for the nutritional monitoring of gerbera cultivated on substrate. The experiment was carried out in greenhouse, in Botucatu (22°51’S and 48°26’W), São Paulo State, Brazil. Five substrate formulations were used and two gerbera cultivars, Red and Cherry, were transplanted to 1-liter pots. Electrical conductivity (EC) and pH of the substrate solution were determined at 1, 15, 29, 43 and 50 days after acclimation (DAA) by adopting the methodologies “pourthru”, dilution of 1:2 (substrate volume/water volume) and dilution of 1:5 (substrate mass /water volume). For the dilution methods, the substrate was removed from the pots, separated from the roots, homogenized and air dried before analysis. In each assessment, 40 pots were used. Linear correlations established among the methodologies were obtained according to the Pearson’s method. EC values of the substrate solution were higher when the method “pourthru” was used due to the lower sample dilution and the nature of the solution displacement in the container. Significant correlations validate the methods while for periodic monitoring, nutritional analysis and eventual correction can be more effectively done by adopting the method “pourthru” since the displacement of the substrate solution using the non-destructive method reduces the costs and accelerates the response.

scholarly journals Adaptação do “PourThru” para avaliação de substratos com diferentes granulometrias

2017 ◽  
Vol 23 (1) ◽  
pp. 22 ◽  
Author(s):  
Fernanda Ludwig ◽  
Amaralina Celoto Guerrero ◽  
Guilherme Amaral Ferreira ◽  
Dirceu Maximino Fernandes ◽  
Roberto Lyra Villas Bôas
Keyword(s):  
Electrical Conductivity ◽  
Particle Size ◽  
Grain Size ◽  
Leach Solution ◽  
Pine Bark ◽  
Particle Sizes ◽  
Substrate Solution ◽  
Periodic Monitoring ◽  
Non Destructive ◽  
Destructive Methods

Periodic monitoring of the substrate solution allows the nutritional control of plants to be done more quickly and conveniently. In order to this monitoring become a routine among the producers of potted flowers, a standardization of non-destructive methods and easy application are required. This study was conducted in order to adapt of the “PourThru” methodology for substrate evaluation with different particle sizes. It was conducted on substrates with different particle sizes. Two tests were performed to define the amount of water to be applied, the time between irrigation and the collect of the leachate. Both tests were done using substrates with grain size 4-2 mm, 2-1 mm <4 mm <2 mm <1 mm and four repetitions. For the test I, we used the factorial 5 x 4 (5 particle sizes and 4 volumes of water), with volumes of 50, 75, 100 and 125 mL. For test II, we used the 5 x 5 factorial (5 granulometry balance and 5 times), with times of 30, 60, 90, 120 and 150 minutes. The leach solution was evaluated for electrical conductivity and pH. The methodology presented showed constraints when the substrates had particle sizes between 4 and 2 mm, and less than 1 mm. The larger the particle sizes is, the greater is the formation of preferential channels that leads to the possibility of mixing the water used as carrier and the solution to be leached is. The smaller the particle size is, the greater is the tendency of adsorption of the nutrients by the particles. For the pine bark substrate and vase with 1.3 L, it is suggested 60 minutes as settling time and the application of 75 mL of water for leaching the displacement.

scholarly journals Electrical conductivity and pH of the substrate solution in gerbera cultivars under fertigation

2013 ◽  
Vol 31 (3) ◽  
pp. 356-360 ◽  
Author(s):  
Fernanda Ludwig ◽  
Dirceu M Fernandes ◽  
Poliana RD Mota ◽  
Roberto L Villas Bôas
Keyword(s):  
Electrical Conductivity ◽  
Experimental Design ◽  
Nutrient Uptake ◽  
Plant Nutrition ◽  
Substrate Solution ◽  
Plant Toxicity ◽  
Paulo State ◽  
Ph Values ◽  
Nutritive Solution ◽  
Golden Yellow

The quality and the profitability on floriculture are intimately linked to the adequate plant nutrition. In the present research we aimed to evaluate the electrical conductivity (EC) and pH of the substrate solution on four different gerbera cultivars subjected to fertigation, with two nutritive solutions. The experiment was carried out in a greenhouse, from May to July 2006, on the Universidade Estadual Paulista, Botucatu, São Paulo state, Brazil. The experiment was carried out under an experimental design of random blocks, in 4×2 factorial arrangement, with four Gerbera cultivars (Cherry, Golden Yellow, Salmon Rose and Orange) and two nutritive solution concentrations: 0.92 and 1.76 dS m-1 EC) during the vegetative stage, and 1.07 and 2.04 dS m-1 during the reproductive stage (S1 and S2, respectively). The nutrients were applied through fertigation, manually performed every day. The EC and pH values of the substrate solution were evaluated weekly, using the 'pourthru' method. Orange and Cherry cultivars had, respectively, the highest and the lowest electrical conductivity of the substrate solution, and Cherry was the most efficient on the nutrient uptake. The solution S2 showed a trend to accumulate salts in the substrate, but without visual symptoms of plant toxicity, leading to the lowest pH values. The 'pourthru' method was efficient when compared to the 1:2 method and can be adopted for substrate solution analysis in gerbera culture.

scholarly journals Electrical conductivity and accelerated aging in amaranth (Amaranthus crueentus L.) seeds

2018 ◽  
Vol 40 (1) ◽  
pp. 44-51
Author(s):  
Thaís D’Avila Rosa ◽  
Ariele Paula Nadal ◽  
Henrique Roberto Maldaner ◽  
Vanessa Nogueira Soares ◽  
Gizele Ingrid Gadotti ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Accelerated Aging ◽  
Water Volume ◽  
Amaranthus Cruentus ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Immersion Period ◽  
Amaranth Seed

Abstract: The objective of this study was to determine adequate conditions of water volume, seed quantity and immersion period to perform the electrical conductivity test, and to analyze the parameters of the accelerated aging test and its correlation with the the physiological potential of amaranth seeds. Five lots of amaranth seeds (Amaranthus cruentus), cultivar BRS Alegria, were used. The initial evaluation of the quality of these lots comprehended the following tests: water content, germination, first germination count, accelerated aging (traditional method, and modified versions, using unsaturated and saturated saline solution for the periods of 24, 48 and 72 h), electrical conductivity in different periods (2, 4, 6, 8 and 24 h), different quantities of water (25, 50 and 75 mL), different seed quantities (100 and 150), and field emergence. It could be concluded that the accelerated aging test at 41 °C, for 72 h, using unsaturated NaCl solution was efficient in the classification of amaranth seed lots in levels of vigor. The electrical conductivity test performed for 8 hours with 25 mL of water and 100 seeds was efficient in the classification of amaranth seeds as to their physiological potential.

scholarly journals Ground reference data for sugarcane biomass estimation in São Paulo state, Brazil

2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Ramses A. Molijn ◽  
Lorenzo Iannini ◽  
Jansle Vieira Rocha ◽  
Ramon F. Hanssen
Keyword(s):  
Reference Data ◽  
Growth Dynamics ◽  
Sao Paulo ◽  
Biomass Estimation ◽  
São Paulo ◽  
Satellite Measurements ◽  
Paulo State ◽  
São Paulo State ◽  
Non Destructive ◽  
Production Dynamics

Abstract In order to make effective decisions on sustainable development, it is essential for sugarcane-producing countries to take into account sugarcane acreage and sugarcane production dynamics. The availability of sugarcane biophysical data along the growth season is key to an effective mapping of such dynamics, especially to tune agronomic models and to cross-validate indirect satellite measurements. Here, we introduce a dataset comprising 3,500 sugarcane observations collected from October 2014 until October 2015 at four fields in the São Paulo state (Brazil). The campaign included both non-destructive measurements of plant biometrics and destructive biomass weighing procedures. The acquisition plan was designed to maximize cost-effectiveness and minimize field-invasiveness, hence the non-destructive measurements outnumber the destructive ones. To compensate for such imbalance, a method to convert the measured biometrics into biomass estimates, based on the empirical adjustment of allometric models, is proposed. In addition, the paper addresses the precisions associated to the ground measurements and derived metrics. The presented growth dynamics and associated precisions can be adopted when designing new sugarcane measurement campaigns.

scholarly journals Adequacy of the Electrical Conductivity Test Methodology for Millet Seeds

2017 ◽  
Vol 9 (11) ◽  
pp. 130 ◽  
Author(s):  
Luanna Karoline Rinaldi ◽  
Diandra Javorski ◽  
Maicon Javorski ◽  
Ana Paula Mourão Simonetti ◽  
Tatiane Priscila Chiapetti ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Quality Control ◽  
The Other ◽  
Water Volume ◽  
Accelerated Ageing ◽  
Seed Imbibition ◽  
Test Methodology

Companies have sought to improve, more and more, the quality control of the seeds produced, improving tests that evaluate the vigor of the seeds with greater speed and precision. The objective of the present work was to study the effects of imbibition time on the results of the electrical conductivity test to evaluate the vigor of millet seeds and to correlate with the other tests carried out. Six seeds lots of the ADR300 cultivar with different vigor levels were used. Germination, first germination count, accelerated ageing, emergence and emergence speed of seedlings in sand and electrical conductivity with variations in water volume were performed (50 And 75 cm3), during the imbibition time of 2, 4, 6 and 8 hours, at 25 ºC. The time of 2 hours of the seed imbibition in 75 cm3 in water proved to be efficient to evaluate the vigor of millet seeds in all lots tested.

scholarly journals CARBON STOCK ESTIMATION AT MINING RECLAMATION AREA: CASE STUDY PT NEWMONT NUSA TENGGARA

2017 ◽  
Author(s):  
Bambang Supriadi ◽  
JONI SAFAAT ADIANSYAH
Keyword(s):  
Carbon Stock ◽  
Plant Biomass ◽  
Initial Conditions ◽  
Total Carbon ◽  
Mining Operations ◽  
Forest Condition ◽  
Periodic Monitoring ◽  
Reclamation Area ◽  
Non Destructive

PT Newmont Nusa Tenggara (PTNNT) is one of mineral mining operations in Indonesia and located at West Sumbawa Regency of West Nusa Tenggara Province. In running its operation, PTNNT is conducting reclamation program to the area that are not disturbed by mining activities. Reclamation program is intended to restore the forest condition similar with the initial conditions and prevent from erosion. In addition, it is obvious that the reclamation forest has also a function as carbon stock. This study aims to determine carbon stock in the PTNNT’s reclamation area particularly in Pit. The method applied is non-destructive sampling methods with estimation of carbon stock using the equations developed by Katterings et al. Estimation of carbon stock is devided into some carbon pools which are biomass of tree, pole and stake, and plant biomass and litter. The research found that the average of total carbon stock in three locations of PTNNT’s reclamation forest (East Dump, Sejorong Dump, and Tongoloka Dump) planted in 2001-2008 is 3,965.95 tonnes carbon or 34.96 tonnes carbon/hectar. In addition, the number of tons of carbon/hectare is influenced by plant growth and it is evidenced by the highest result of carbon stock calculation in 2006 compared with the previous year. This is supported also by the result of periodic monitoring conducted by PTNNT if the growth of plants planted in 2006 is better that the previous year.

scholarly journals Tests for evaluating the physiological quality of pitaya seeds

2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4047
Author(s):  
Thiago Alberto Ortiz ◽  
Aline Moritz ◽  
Lúcia Sadayo Assari Takahashi ◽  
Mariana Ragassi Urbano
Keyword(s):  
Electrical Conductivity ◽  
Pearson Correlation ◽  
Accelerated Aging ◽  
Seed Vigor ◽  
Water Volume ◽  
Germination Test ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Physiological Quality

Germination test is used to assess the physiological quality of seeds; however, since it is carried out under ideal conditions, this test has not been shown sufficient for this purpose. Instead, it is possible to use vigor tests, although the lack of standardized methodologies has reduced their applicability and reproducibility. Thus, this study aimed to develop methodologies for conducting tests of germination, accelerated aging, and electrical conductivity for the evaluation of the physiological quality of pitaya seeds. For this purpose, seeds from ripe Hylocereus undatus fruits were used. A completely randomized experimental design was used with four replications. The physiological quality of the seeds was assessed using germination, accelerated aging, and electrical conductivity tests, and the speed of germination index (SGI) and mean germination time (MGT) were determined for both the germination test and accelerated aging test. For the statistical analysis, we performed regression model adjustments and calculated the Pearson correlation coefficient (p < 0.05). The germination test for H. undatus seeds can be performed at 25 °C, with the aim of reaching the highest SGI and lowest MGT values. The accelerated aging test can be conducted at 43 °C for 48 h, because combining these factors favors the expression of seed vigor, allowing seeds to achieve the maximum SGI and minimum MGT, while reducing the time of the assay. The electrical conductivity test can be performed using 25 seeds at a temperature of 30 °C and a water volume of 10 mL, since under these conditions there is less interference from external factors on the leachate content of the solution.

scholarly journals Portable meters for nutritional assessment in plants of gerbera fertigated with electrical conductivity levels

2014 ◽  
Vol 18 (3) ◽  
pp. 258-262 ◽  
Author(s):  
Poliana R. D'A. Mota ◽  
Roberto L. Villas Bôas ◽  
Fernanda Ludwig ◽  
Dirceu M. Fernandes ◽  
Marcos V. Folegatti
Keyword(s):  
Electrical Conductivity ◽  
Nutritional Status ◽  
Plant Tissue ◽  
Nutritional Assessment ◽  
Block Design ◽  
Rapid Testing ◽  
Substrate Solution ◽  
Chlorophyll Meter ◽  
Randomized Block Design ◽  
Rapid Tests

Rapid tests to assess the nutritional status of plants gerbera can make easier the decision of any adjustments in the fertilization of the substrate. The study was conducted to evaluate nutritionally fertigated gerbera plants with increasing levels of electrical conductivity (EC), using portable meters nitrate and potassium, and chlorophyll. For this, two experiments were conducted. A randomized block design with five levels of EC (0.5, 2.0, 3.5, 5.0 and 6.5 dS m-1) and four replications was used. Cherry cultivar was used in the first experiment. In the second experiment, two cultivars (Cherry and Salmon Rose) were used. In the first experiment, the sap of the leaves was subjected to rapid testing of N-NO3- (equipment Cardy Horiba C -141). N-NO3- and K+ (C-131) were determined in the substrate solution. The intensity of the green leaf, in the second experiment was evaluated with portable Chlorophyll Meter. The N content in the indicator leaf in the first and N and K contents in the plant in the second experiment were determined. Rapid tests are presented as good indicators of the level of N-NO3- and K+ in plant tissue, with the advantages of convenience and speed of determination, facilitating monitoring of fertilization of the substrate by producers and technicians.

A Non-Conventional Technique for Evaluating Welded Joints Based on the Electrical Conductivity

2014 ◽  
Vol 611-612 ◽  
pp. 671-676 ◽  
Author(s):  
Telmo G. Santos ◽  
Gonçalo Sorger ◽  
Pedro Vilaça ◽  
R.M. Miranda
Keyword(s):  
Electrical Conductivity ◽  
Solid State ◽  
Welded Joints ◽  
Conventional Technique ◽  
Carbon Steels ◽  
Fusion Welding ◽  
Friction Stir ◽  
Wide Range ◽  
Welding Processes ◽  
Non Destructive

Recent studies showed that electrical conductivity is a valuable technique to identify the different zones of solid-state welded joints with a good correlation with the microstructure and hardness. This is a relevant result since this technique is expedite and, in some cases, non destructive. The concept was applied to other welding processes as the ones involving fusion and to a wide range of materials. For this, a comprehensive study was performed using friction stir welding, tungsten inert gas (TIG) and gas metal arc (MAG) welding processes in either bead on plate or butt joints in: carbon steel, magnesium and titanium. Eddy current non-destructive testing (NDT) was used to measure the electrical conductivity at different depths in transverse sections of the processed materials. The obtained profiles were compared to the hardness profiles in the same sections. As a result, a good correlation was observed in most materials welded by solid state and by fusion processes. The variation of the electrical conductivity closely follows the one detected in the hardness. Another interesting conclusion is that, even for fusion welding of carbon steels, the technique has potential to complement the hardness measurements and microstructural observations, allowing to identify the distinct zones of welds in materials commonly used in industry.

scholarly journals Lumped-element model for subglacial transport of solute and suspended sediment

1996 ◽  
Vol 22 ◽  
pp. 152-159 ◽  
Author(s):  
Garry K. C. Clarke
Keyword(s):  
Electrical Conductivity ◽  
Differential Equations ◽  
Water Pressure ◽  
Water System ◽  
Coupled System ◽  
Yukon Territory ◽  
Water Volume ◽  
Charge Voltage ◽  
Lumped Element ◽  
Lumped Element Model

Present understanding of the subglacial water system and its role in transporting solute and sediment is largely based on subglacial observations of water pressure, turbidity and electrical conductivity and on portal measurements. Such data reveal a wealth of intriguing phenomena, but convincing interpretations can be elusive. Although a proper mathematical description of the subglacial water system would unquestionably lead to a coupled system of non-linear partial differential equations, it is not fruitful to introduce this level of complexity until the important physical processes have been identified and quantified. Lumped-element models offer an efficient approach to examining the complex but dimly perceived physics of the subglacial water system. Water volume, hydraulic head, discharge and flow resistance have the respective electrical analogues of charge, voltage, current and ohmic resistance. Thus, subglacial hydraulic circuits can be approximated by electrical circuits. Mathematically, this circuit description commonly leads to a coupled system of algebraic and differential equations which can be solved numerically. It is straightforward to enrich this representation by adding sources and sinks of solute and sediment. To demonstrate the method, model results are compared to records of subglacial pressure, electrical conductivity and turbidity measured beneath Trapridge Glacier, Yukon Territory, Canada.

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