CALIBRATION OF A WEIGHING LYSIMETER FOR MEASURING COCOA EVAPOTRANSPIRATION

ABSTRACT Well-operated and calibrated weighing lysimeters reliably determine the water demand of agricultural crops, and the quality of the data is evaluated through the error analyses attributed to the instrument. The objective of this study was to determine performance parameters of a weighing lysimeter and to evaluate its adequacy for the direct determination of cocoa crop evapotranspiration. The lysimeter with 1.44 m2 surface, supported on four load cells installed in the experimental area of the Graduate Program in Agricultural Engineering of the Universidade Federal do Recôncavo da Bahia, was calibrated at 3:00 a.m., using known masses at intervals of 02 minutes in five cycles of addition and removal. Data were collected using a datalogger coupled to four load cells with an individual capacity of 1000 kg, programmed to perform readings every 01 second, storing the averages of 15 minutes. The lysimeter showed excellent accuracy, with r2greater than 0.99 in the correlation between the standard masses and the signal of the load cells and standard error of linear regression estimate of 0.03 mm. The combination of repeatability and hysteresis errors with an uncertainty of 0.19% showed that the load cells have accuracy of ±0.07 mm, with resolution of 0.00033 mV, and sensitivity to detect mass changes below 0.1 mm, the system is adequate for direct measurement of cocoa ETc at time intervals of less than one hour.

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Effects of Macronutrients in the Physiological Quality of Soybean Seeds

Journal of Agricultural Science ◽

10.5539/jas.v10n5p312 ◽

2018 ◽

Vol 10 (5) ◽

pp. 312

Author(s):

Geliandro Anhaia Rigo ◽

Luis Osmar Braga Schuch ◽

Willian Silva Barros ◽

Rodrigo Lamaison de Vargas ◽

Vinícius Jardel Szareski ◽

...

Keyword(s):

Graduate Program ◽

Plant Tissues ◽

Soybean Seeds ◽

Rio Grande Do Sul ◽

Genetic Characteristics ◽

Physiological Quality ◽

High Concentrations ◽

Nitrogen Phosphorus

The aim of this work was to correlate macronutrient content of soybean seeds to physiological quality of different cultivars. The work was developed in the Federal University of Pelotas, in the facilities of the Seed Science and Technology Graduate Program. The experimental design was randomized blocks in arranged in four replicates. The following soybean cultivars were used: BMX Apolo RR (12 lots), BMX Ativa RR (13 lots), BMX Energia RR (26 lots), BMX Força RR (24 lots), BMX Impacto RR (35 lots), BMX Magna RR (16 lots), BMX Turbo RR (44 lots), BMX Potência RR (82 lots) and NA 5909 RR (28 lots), with seeds produced in northwest Rio Grande do Sul. The determination of nutritional contents found in plant tissues of soybean seeds, were measured: Nitrogen (N), Phosphorus (P), Potassium (K), Magnesium (Mg), Calcium (Ca), Sulfur (S). The macronutrient contents of the seeds vary according to genetic characteristics of the cultivars, with higher oscillations of nitrogen, phosphorus, magnesium and sulfur contents present in soybean seeds. Potassium and calcium are defined as the most stable nutrients for the cultivars and seed lots analyzed. High concentrations of nitrogen, phosphorus and calcium are determinants for the physiological quality of soybean seeds.

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Changes in Phytochemicals and Determination of Optimum Fermentation Time during Black Tea Manufacturing

Journal of Scientific Research ◽

10.3329/jsr.v12i4.45452 ◽

2020 ◽

Vol 12 (4) ◽

pp. 657-664

Author(s):

M. M. Rahman ◽

M. M. Hossain ◽

R. Das ◽

I. Ahmad

Keyword(s):

Black Tea ◽

Quality Parameters ◽

Biochemical Changes ◽

Enzymatic Oxidation ◽

Time Intervals ◽

Fermentation Time ◽

Tea Quality ◽

Processing Steps

Black tea processing consists of four steps, namely withering, CTC, fermentation and drying, while cup quality made tea mostly controlled by fermentation step. This study evaluated biochemical changes at different stages of black tea processing in Bangladesh and determined the optimum fermentation time. Samples were collected from different tea processing stages to measure major phytochemicals and time intervals during fermentation to measure theaflavins and thearubigins ratio. Caffeine content was the least susceptible to processing steps. Biochemical changes started at withering, cell maceration and enzymatic oxidation started at CTC processing, thus the major reduction in the reducing sugar (20.46 to 04.95 ppm), catechin (16.88 to 7.95 ppm) and polyphenol (42.30 to 30.73 ppm) occurred here. The significant changes appeared during fermentation when polyphenol content decreased from 44.66 to 18.23 and catechin from 17.41 to 03.98 ppm due to the breakdown of these compounds to theaflavins (TF) and thearubigins (TR). The TF and TR ratio increased with fermentation time, and the highest of 1:8.4 was found at 50 min, which turned into 1:10 in the final product. The made tea quality parameters were comparable or better at fermentation time of 50 min than the quality of the black tea available in market.

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Growth, production and water consumption of coriander grown under different recirculation intervals and nutrient solution depths in hydroponic channels *

Emirates Journal of Food and Agriculture ◽

10.9755/ejfa.2020.v32.i4.2094 ◽

2020 ◽

pp. 281 ◽

Cited By ~ 1

Author(s):

Mairton Gomes da Silva ◽

Tales Miler Soares ◽

Hans Raj Gheyi ◽

Islan Passos Costa ◽

Rafael Souza Vasconcelos

Keyword(s):

Nutrient Solution ◽

Water Consumption ◽

Graduate Program ◽

Cropping Systems ◽

Hydroponic System ◽

Agricultural Engineering ◽

Negative Effect ◽

Growth Production ◽

Use Efficiency

Water is an increasingly scarce resource in arid and semiarid regions. The irregular precipitation makes hydroponics a recommended technique for these regions, since it demands less water compared to conventional cropping systems. Two experiments, one from May to June 2016 (autumn) and other from March to April 2017 (summer-autumn), were conducted in a hydroponic system in PVC tubes, using the Deep Flow Technique (DFT). A 2 x 3 x 2 factorial arrangement in split-plot was used, which consisted of two nutrient solution depths (0.02 and 0.03 m) and three recirculation intervals of the nutrient solution (0.25, 12 and 24 h), with two coriander cultivars (‘Tabocas’ and ‘Verdão’) in the sub-plots, which were cultivated in the same hydroponic channel. Plant height, shoot fresh and dry matters, water consumption, water use efficiency and visual quality of the coriander plants were evaluated. The coriander cv. ‘Verdão’ was more tolerant to climatic variations, especially when plants were grown in channels with nutrient solution depth of 0.02 m and recirculation interval of 0.25 h, presenting higher growth and production. The recirculation intervals of 12 and 24 h had a negative effect on the variables evaluated; though, this effect was more significant in the summer-autumn experiment, affecting the quality of the plants harvested, especially those of the cv. ‘Tabocas’. It may be concluded that the cultivation of the coriander in the DFT system in PVC tubes is viable, especially in sites with insecure electricity supply. * Paper extracted from the doctoral thesis of the first author presented in the Post Graduate Program in Agricultural Engineering of the Federal University of Recôncavo of Bahia, Brazil

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Procedures for the Determination of Lipase Activity and Percent Trivernolin in Vernonia galamensis spp. galamensis using Gas Chromatography

HortScience ◽

10.21273/hortsci.32.3.483b ◽

1997 ◽

Vol 32 (3) ◽

pp. 483B-483

Author(s):

M.A. Sieberg ◽

D.K. Stumpf ◽

D.T. Ray

Keyword(s):

Lipase Activity ◽

Vernolic Acid ◽

Octadecenoic Acid ◽

Volatile Oil ◽

Vernonia Oil ◽

Vernonia Galamensis ◽

Time Intervals ◽

Total Seed

Vernonia galamensis spp. galamensis is a short-season oilseed plant naturally producing an epoxy fatty acid, vernolic (cis-12, 13-epoxy-cis-9, 10-octadecenoic) acid. Trivernolin, a triglyceride with three vernolic acid moieties, is the highestquality oil produced by vernonia. Industrial interest in vernonia oil includes use for metal coating and as a non-volatile oil in paint. Seed lipase causes production of free fatty acids (FFA) from triglycerides (TG) in preand post-crushed seeds, thereby decreasing the quality of vernonia oil. Consequently, production of FFA can be used as a measure of lipase activity. Our research has developed a technique for detecting the production of FFA and the accompanying diand monoglycerides. We are able to quantify FFA in relation to total seed lipid. FFA were measured at time of crushing and at selected time intervals thereafter. This allowed us to assess FFA in intact seeds and in seeds that have been crushed with the lipase able to hydrolyze the TG. Significant differences were found between accessions for all times tested. This procedure was developed to enable us to screen plants in our breeding program for seed lipase activity. We are also screening our germplasm for triglyceride composition to select those plants producing the highest percentage of trivernolin. We will use this data to describe the genetics of both traits.

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Effects of Cropping Year and Artificial Fertilization on Alveographic Quality of GK Öthalom Winter Wheat Variety

Acta Agraria Debreceniensis ◽

10.34101/actaagrar/16/3300 ◽

2005 ◽

pp. 126-133

Author(s):

Árpád Tóth ◽

Péter Sipos ◽

Győri Zoltán

Keyword(s):

Winter Wheat ◽

Wheat Variety ◽

Wheat Quality ◽

Strong Connection ◽

Wheat Varieties ◽

Winter Wheat Variety ◽

Agricultural Engineering ◽

Artificial Fertilization

Qualification of winter wheat became more complex for Hungary, after the expansion of the EU. Use of Chopin alveograph is a general method in Western- and Southern Europe. This method is not traditional in Hungary, so determination of alveographic properties of Hungarian winter wheat varieties is very important. Artificial fertilization is one very important component of applied agricultural engineering, which effects winter wheat quality. The another factor is the weather or rather the cropping year, which effects winter wheat quality too. We examined both of them and the alveographic quality of GK Öthalom winter wheat variety between 1996 and 2003.We found that cropping year has significant effect on the alveographic quality of GK Öthalom winter wheat variety on each treatment of artificial fertilization. We found no connection between quantities of precipitations of vegetation periods and the W values of GK Öthalom.We found a strong connection in 1999 and 2003 as well as a very strong connection in 1996, 1997 and 2002, between the increase of fertilizer dose and W values of GK Öthalom. Treatments of artificial fertilization had a significant effect to W values of GK Öthalom in 2001 and 2002. The differences between the two methods are because of large standard deviation of the results.

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BKG’s new series of 24-hour and 1-hour VLBI experiments

10.5194/egusphere-egu21-8950 ◽

2021 ◽

Author(s):

Anastasiia Girdiuk ◽

Gerald Engelhardt ◽

Dieter Ullrich ◽

Daniela Thaller ◽

Hendrik Hellmers

Keyword(s):

Reference Frames ◽

Global Network ◽

Time Intervals ◽

Earth Orientation Parameters ◽

Terrestrial Reference Frames ◽

The Earth ◽

Station Coordinates ◽

Orientation Parameters

With the VLBI technique radio sources are observed in dedicated time intervals. The most usual length of these observing sessions are 24 and 1-hour long. 24-hour long experiments usually incorporate a global network of stations, and, thus, are the prominent source of a consistent determination of all Earth Orientation Parameters (EOPs), celestial and terrestrial reference frames. The shorter experiments are designed to determine dUT1 parameter only. The number of short or intensive sessions is growing every year. Also some of them involve 3-4 stations in observation programs instead of standard 2-station mode. This leads to a larger number of observations per session, a better coverage of the Earth, and, consequently more accurate dUT1 estimates.All 24-hour and 1-hour sessions since 1984 up to now were re-processed by BKG using the most up-to-date modelling within the parameter estimation. This results in new series of consistently estimated EOPs, station coordinates and troposphere parameters.In this contribution we present our new series and investigate the quality of the obtained geodetic products, especially the EOPs. The work is focused on the consistency between dUT1 parameters derived from 24-hour and 1-hour sessions, respectively. In this study we pinpoint challenges and prospects of the inclusion of 1-hour experiments into the standard analysis of the 24-hour experiments.

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Green detection of the olive fruit fly pest by the direct determination of its sexual pheromone

Analytical Methods ◽

10.1039/c5ay00491h ◽

2015 ◽

Vol 7 (17) ◽

pp. 7228-7233 ◽

Cited By ~ 4

Author(s):

María del Carmen Alcudia-León ◽

Soledad Cárdenas ◽

Miguel Valcárcel ◽

Rafael Lucena

Keyword(s):

Olive Oil ◽

Direct Determination ◽

Fruit Fly ◽

Bactrocera Oleae ◽

Olive Fruit Fly ◽

Sexual Pheromone ◽

Olive Fruit ◽

Olive Trees

Bactrocera oleaeGmelin, the olive fruit fly, is considered a serious pest in the cultivation of olive trees since the larvae feed on the fruit damaging the productivity and quality of the final products (olive fruit and olive oil).

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