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Julie M. Tarara, Bernardo Chaves, Luis A. Sanchez, and Nick K. Dokoozlian

Vilas, 1992 ). We developed an automated system that provides a remote and dynamic indicator of annual vegetative and fruit growth, or increase in mass, and thus an opportunity to identify the onset of L analytically. Briefly, the trellis tension

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Martina Göttingerová, Michal Kumšta, Eliška Rampáčková, Tomáš Kiss, and Tomáš Nečas

extract was analyzed in a LC-10A HPLC system (Shimadzu, Tokyo, Japan). The samples were run in an analytical column (Alltima HP C18, 3 μm, 3·150 mm; Avantor, Randor, PA), where 15 mM perchloric acid solution was used as the mobile phase. Detection was

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Gail A. Langellotto and Abha Gupta

with low sample sizes and/or weak treatment effects ( Arnqvist and Wooster, 1995 ). An additional benefit of meta-analytical techniques is that they can quantify the magnitude of a treatment effect for individual studies included in the analysis, as

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Arthur Villordon

to become familiar with the tools used in the storage, analysis, and sharing of large data sets. Big data concepts and analytics can also be applied to online learning applications, including monitoring and evaluation of learner performance ( Picciano

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Yan Wang and Stanley J. Kays

Flavor quality is one of the most difficult traits to select in plant breeding programs due to the large number of sensory panelists required, the small number of samples that can be evaluated per day, and the subjectivity of the results. Using sweetpotato [Ipomoea batatas (L.) Lam.] as a model, clones exhibiting distinctly different flavors were analyzed for sugars, nonvolatile acids, and aroma chemistry to identify the critical flavor components. Differences in sugars, sucrose equivalents, nonvolatile acids, and 19 odor-active compounds were identified that accounted for differences in flavor among the clones. Using the intensity of the aroma per microliter for each of the 17 most important aroma-active compounds (maltol, 5-methyl-2-furfural, 2-acetyl furan, 3-furaldehyde, 2-furmethanol, benzaldehyde, phenylacetaldehyde, β-ionone, 1,2,4-trimethyl benzene, 2-pentyl furan, 2,4-decadienal, 2,4-nonadienal, linalool, geraniol, cyperene, α-copane and a sesquiterpene) and the relative sweetness of individual sugars × their respective concentrations, multivariate (principal component and cluster) analysis allowed accurate classification of the clones according to flavor type without sensory analysis. The level of precision was such that sweetness, starch hydrolysis potential, and the concentration of β-carotene could be accurately predicted by quantifying specific volatiles. Analytical assessment of flavor would greatly facilitate the accurate evaluation of large numbers of progeny, the simultaneous selection of multiple flavor types, and the development of superior new cultivars for a wide cross-section of food crops.

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Lavesta C. Hand, Kayla M. Eason, Taylor M. Randell, Timothy L. Grey, John S. Richburg, Timothy W. Coolong, and A. Stanley Culpepper

, irrigation, or degradation, then it would offer a significant improvement in preplant herbicide options. Therefore, analytical and bioassay experiments were conducted to quantify variable rates of 2,4-D removal from plastic mulch over time and with irrigation

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Aparna Gazula, Matthew D. Kleinhenz, Joseph C. Scheerens, and Peter P. Ling

, facilitate cultivar development, and provide other benefits. For lettuce, more information is needed to understand the genetic and environmental controls of anthocyanin levels and to use either anthocyanin levels measured analytically or descriptions of color

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Eric T. Stafne

Analytics (Twitter, Inc.). Analysis was performed in JMP (version 12; SAS Institute, Cary, NC) with the Fit model procedure and means were separated by Tukey’s honestly significant difference test at P ≤ 0.05. Results and discussion The average Twitter

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Carl J. Rosen, Mohamed Errebhi, and Wang Wenshan

An important aspect of establishing critical sap nutrient concentrations for diagnostic purposes is to determine the accuracy and precision of the analytical method used. We compared a Cardy flat membrane NO3 electrode, a Hach portable NO3 electrode, and a Wescan N analyzer for their ability to determine NO3 concentrations in sap of potato petioles. The Hach and Wescan instruments require diluted sap, while nondiluted sap can be used with the Cardy. Nitrate-N concentrations in nondiluted petiole sap measured with the Cardy electrode were 100 to 200 mg·liter–1 higher than the other two methods. Using sap diluted with 0.15 M Al2(SO4)3 tended to lower Cardy NO3 readings to concentrations closer to the other methods, but made the procedure more complicated for practical use. We also compared a Cardy K electrode with flame emission spectroscopy for determining K concentrations in sap. Using nondiluted sap with the Cardy procedure resulted in K concentrations 1000 to 1700 mg·liter–1 lower than those determined by flame emission. Diluting sap with 0.15 M Al2(SO4)3 for use with the Cardy electrode resulted K concentrations similar to those determined by flame emission. Implications for using the electrodes for diagnostic purposes will be discussed.

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Carl J. Rosen, Mohamed Errebhi, and Wenshan Wang

An important aspect of establishing critical sap nutrient concentrations for diagnostic purposes is to determine the accuracy of the analytical method used. We compared a Cardy flat membrane NO3 electrode, a Hach portable NO3 electrode, and a Wescan N analyzer for their ability to determine NO3 concentrations in sap of potato (Solanum tuberosum L.) petioles. The Hach and Wescan instruments require diluted sap, while nondiluted sap can be used with the Cardy. Nitrate-N concentrations in nondiluted petiole sap measured with the Cardy electrode were 90 to 120 mg·L–1 higher than the other two methods. Using sap diluted with 0.075 m aluminum sulfate tended to lower Cardy NO3 readings to concentrations closer to the other methods, but made the procedure more complicated for practical use. We also compared a Cardy K electrode with flame emission spectroscopy for determining K concentrations in sap. Using nondiluted sap with the Cardy procedure resulted in K concentrations 200 to 2500 mg·L–1 lower than those determined by flame emission, depending on K concentration of the sap. Diluting sap with 0.075 m aluminum sulfate or deionized water for use with the Cardy electrode resulted in K concentrations similar to those determined by flame emission.