• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.3
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• pp.194-204
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• 2020

Cultivar parameters, which are key inputs to a crop growth model, have been estimated using observation data in good quality. Observation data with high quality often require considerable labor and cost, which makes it challenging to gather a large quantity of data for calibration of cultivar parameters. Alternatively, data in sufficient quantity can be collected from the reports on the evaluation of cultivars by region although these data are of questionable quality. The objective of our study was to assess the quality of crop and management data available from the reports on the regional adaptation trials for rice cultivars. We also aimed to propose the measures for improvement of the data quality, which would aid reliable estimation of cultivar parameters. DatasetRanker, which is the tool designed for quantitative assessment of the data for parameter calibration, was used to evaluate the quality of the data available from the regional adaptation trials. It was found that these data for rice cultivars were classified into the Silver class, which could be used for validation or calibration of key cultivar parameters. However, those regional adaptation trial data would fall short of the quality for model improvement. Additional information on management, e.g., harvest and irrigation management, can increase the quantitative quality by 10% with the minimum effort and cost. The quality of the data can also be improved through measurements of initial conditions for crop growth simulations such as soil moisture and nutrients. In addition, crop model improvement can be facilitated using crop growth data in time series, which merits further studies on development of approaches for non-destructive methods to monitor the crop growth.

• Journal of Life Science
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• v.26 no.9
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• pp.1033-1040
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• 2016

In Korea, the aerial parts of the halophyte Salicornia europaea, known as hamcho, are used in salads in April–June and in oriental medicine in September–October In this study, with the aim of developing functional foods to aid blood circulation, hot water extract (HWE) and ethanol extract (EE) were prepared using hamcho harvested from the fields of Shinan, Jeonnam, Korea on 5th April (HWE-04, EE-04), 5th July (HWE-06, EE-06), 5th August (HWE-08, EE-08), 5th September (HWE-09, EE-09), and 5th October (HWE-10, EE-10), and their antioxidant and antithrombosis activities were evaluated. Among the HWEs, HWE-10 showed the highest concentration of total polyphenols and total flavonoids (22.4 and 17.6 mg/ml, respectively), and EE-09 had the highest concentration among the EEs (20.1 and 19.3 mg/ml, respectively). Among the HWEs and EEs, HWE-08 and EE-08 had the highest total sugar and reducing sugar content. In the antioxidation assay, HWE-10 and EE-09 showed strong reducing power, as well as DPPH, ABTS, and nitrite scavenging activities. The calculated RC₅₀s of EE-09 against DPPH, ABTS, and nitrite were 578, 277, and 68.8 μg/ml, respectively. The antithrombosis activity assay revealed that HWE-04, HWE-06, EE-04, and EE-06 had anticoagulation activity against coagulation factors and that HWE-08, HWE-09, EE-08, and EE-09 expressed strong thrombin inhibitory activity, which was comparable to the antithrombosis activity of aspirin. In addition, EE-06 and HWE-08 exhibited strong aggregation inhibitory activities against human platelets. The results suggest that extract from hamcho harvested in particular periods and prepared using a defined solvent has strong potential as a novel food ingredient and an antioxidant and antithrombosis agent.

• Korean Journal of Plant Resources
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• v.32 no.4
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• pp.312-317
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• 2019

This study was conducted with the purpose of examining the suitability of Euphorbia jolkinii Boiss. as cut flower, so that it may be introduced as a new ornamental crop. For this purpose, effect of various holding solutions on vase solution uptake rate, vase life, and relative fresh weight of cut flowering branches of E. jolkinii was examined. After harvest, cut branches were treated with 10, 50, and $100mg{\cdot}L^{-1}$ of 8-hydroxyquinoline sulfate (8-HQS), 0.1 and 0.2 mM of silver thiosulfate (STS), Chrysal, and Floralife. The cut branches of E. jolkinii were placed under the environmental conditions maintained at air temperature of $22.6^{\circ}C$, relative humidity of 45%, and 9/15h photoperiod that was controlled using fluorescent lamps (light intensity of $9.89{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). A holding solution containing $10mg{\cdot}L^{-1}$ 8-HQS was found to be significantly effective for vase solution uptake rate compared to control, $50mg{\cdot}L^{-1}$ 8-HQS, and $100mg{\cdot}L^{-1}$ 8-HQS treatments. However, no significant difference was found in vase life between the branches treated with $10mg{\cdot}L^{-1}$ 8-HQS holding solution and branches of the control group. Increasing holding solution concentrations of STS was found to have negative effect on the vase life of cut E. jolkinii branches. Relative fresh weight of cut E. jolkinii branches were significantly decreased by two commercial holding solutions, Chrysal and Floralife. It is expected that these results would aid further studies on utilization of E. jolkinii as cut flower crop.