• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.162-166
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• 1999

In 1998, there was heavy precipitation of 60 days with amount of 1,042mm from June to September in Andong. Upland crop was severely injured by excessive moisture(EM) on poor drainage field. In this trial, effects of EM on the growth characteristics and yield in Peucedanum japonicum Thunberct and Rehmannia glutinosa Liboschitz was investigated. In Peucedanum japonicum Thunberct, growth of root was decreased more severely than that of aerial part by EM injury, and fresh weight of root per ha was decreased by $21{\sim}80%$ at different degree of EM injury compared to that of normal growth. In Rehmannia glutinosa Liboschitz, percent of withered plant was $10{\sim}52%$ at different degree of EM injury. and rhizome's number per plant and diameter was extremely decreased by EM injury. Fresh weight of rhizomes per ha was decreased by $19{\sim}83%$ at different degree of EM injury compared to that of normal growth.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.354-361
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• 2012

This study was conducted to evaluate on the freezing tolerance of introduced blueberry cultivars in Korea and to investigate availability of portable timber moisture meter for simple and rapid diagnosis of blueberry-shoot damage by freezing during wintering. Frost tolerance of blueberry cultivars showed big difference that rates of blueberry-shoot death were widely distributed from about 0% to 100% after wintering. Optical density in TTC reduction of blueberry twig treated low temperature was low in order of $-40^{\circ}C$ < $-21^{\circ}C$ < $4^{\circ}C$. Hardiness evaluation of visible injury in the cross-sectional surface color did not agree with that of rates of blueberry-shoot death during wintering. Lowest water content of blueberry stem measured by timber moisture tester during wintering was about 15%. During wintering, water contents of blueberry stems were higher at lower part of tree, but were low at end part of stems, and then when the blueberry grew again for spring, the water content gradually increased to 20~40%. Water content of blueberry stem with freezing injury during wintering decreased to under 5% by desiccation. Therefore it is assummed that the moisture content of blueberry stem injured by freezing during wintering was about under 14%, and it is expected that portable timber moisture meter could be available for rapid diagnosis of blueberry freezing injury in field.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.2
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• pp.45-52
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• 2015

Cool-season turfgrass is a rapidly increasing of usage for the revegetation of waterside slopes in dams, lakes and rivers. The purpose of this research is to identify the flooding tolerance of cool-season turfgrass with respect to the flooding periods of 0(control), 2, 4 and 6 days, respectively. The surface coverage ratio, turfgrass injury and soil moisture content were measured to assess the flooding tolerance of cool-season turfgrass. The increase in the flooding periods with 4 and 6 days resulted in the lower surface coverage ratio for cool-season turfgrass while no significant difference was found in the 2 days flooding when compared to 0 day (the control plot) flooding plot. In case of the turfgrass injury and the soil moisture content, however, the higher values were found with the increase of flooding periods in 2, 4 to 6 days. We observed that the higher the turfgrass injury and soil moisture content increased, the lower the surface covrage ratio decreased. In these regards, we also observed that the tolerance of cool season turfgrass were high in the 2 days flooding condition, medium in the 4 days flooding condition and low in the 6 days flooding condition. The flooding tolerance of cool-season turfgrass was gradually weakened in over 2 days flooding periods due to $O_2$ deficiency in the anaerobic soil condition. Therefore, we could suggest cool-season turfgrass within 2 days flooding periods for the revegetation of waterside slopes in dams, lakes and rivers.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.168-175
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• 2011

This study was conducted to examine the impacts of different soil water potentials on environmental soil properties related to the moisture injury of Korean raspberry (Rubus coreanus Miq.). Soil water potential in the plastic film house plots was differentiated from -5 to -40 kPa. Soils in the plots contained 5.6% of plant available water. Increasing soil water contents based on the changes in water potential increased soil pH and exchangeable $Ca^{2+}$ content and decreased exchangeable $K^+$ and total N contents. It also declined soil organic matter content at 9 days after water treatments. Relationship between water potential and soil water content was given as an exponential equation, y = 96.534 - 20.28In(x). In particular, when the water potential was higher than -20 kPa (27.5% of soil moisture content), it decreased chlorophyll content in the raspberry leaves, inhibited N uptake by the plant, and increased phosphorus content with increasing days after water treatment. Also, as the 7 days after water treatment at higher than -20 kPa of water potential, the root activity of the plant was significantly decreased, and trunk (top)/root (T/R) ratio of the plant markedly declined until 9 days after water supply. Carbohydrate contents in the raspberry plant leaves and roots at dormant stage were the lowest at -5 and -10 kPa of water potential plots, and it may cause winter injury to the plant.

• Journal of Ginseng Research
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• v.35 no.4
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• pp.449-456
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• 2011

Plant leaf cuticle is related to the prevention of moisture loss, transpiration, and diffusion of light reflection. The purpose of this study was to examine the morphological characteristics of ginseng leaves in ginseng plants resistant and susceptible to hightemperature injury (HTI) to be related with the leaf-burning. For the HTI resistant lines Yunpoong, high-temperature injury resistance (HTIR) 1, HTIR 2, and HTIR 3, and the HTI-susceptible line Chunpoong, the cuticle densities were 53.0%, 46.2%, 44.9%, 48.0%, and 17.0%; the adaxial leaf cuticle layers were 141.3, 119.7, 119.7, 159.4, and 85.0 nm in thickness; the abaxial leaf cuticle layers were 153.6, 165.8, 157.9, 199.6, and 119.4 nm in thickness; and the stomtal lengths were 21.7, 32.4, 29.4, 30.9, and $21.8{\mu}m$, respectively. All of these aspects suggest that HTI resistant lines have higher cuticle density, thickicker adaxial and abaxial leaf cuticle layers, and longer of stomta length than the HTI-susceptible line, protecting leaves from moisture loss and excessive transpiration under high temperatures to be resistant against the leaf-burning.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.80-92
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• 1977

This experiment investigated the effect of various moisture levels on the top and root growth of barley and its yield. Resistant varieties to excess moisture injury shortened plant height, but tillered more, having creeping plant type compared with ordinary one, and greater portion of root of this varieties occured at the deeper soil depths with longer root length. However, susceptible one to excess moisture injury showed an inversed trend when compared with the untreated one. Oversaturated treatment compared with the untreated increased a little bit soil temperature and Eh of soil. Increased root activity and increased yield were obtained with resistant varieties compared with the untreated. Lower root activity and less yield than those of the untreated were observed in both extreme treatments. Yield reduction in both the extreme treatments was mainly due to reduction of tiller number, grain number and 1, 000-grain weight. Highest yield reduction was marked at the stage of internode elongation in the oversaturated and at the booting stage in the overdried treatment.

• Journal of Korean Critical Care Nursing
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• v.16 no.3
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• pp.24-33
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• 2023

Purpose : This study aims to establish an optimal cut-off score on the Braden scale for the assessment of pressure injury to detect pressure injury risks among inpatients in a South Korean tertiary hospital. Methods : This retrospective study used electronic medical records, from January to December 2022. A total of 654 patients were included in the study. Of these, 218 inpatients with pressure injuries and 436 without pressure injuries were classified and analyzed using 1:2 Propensity Score Matching (PSM), and the generalized estimating equation was performed using SPSS Version 26 and the R Machlt package program. Results : The cut-off value on the Braden scale for distinguishing pressure injury was 17 points, and the AUC (area under the ROC curve) was 0.531 (0.484-0.579). The sensitivity was 56.6% (45.5-67.7%) and the specificity was 69.7% (66.0-73.4%). With 17 points, the Braden scale cut-off distinguished those who had pressure injuries from those who did not at the time of admission (p < .03). In the pressure injury group, the Braden score on the day of the pressure injury was 14, with significant results in all subcategories except the moisture category. Conclusion : Our findings revealed that a cut-off value of 17 was optimal for predicting the risk of pressure injuries among tertiary hospital inpatients. Future studies should evaluate the optimal cut-off values in different clinical environments. Additionally, it is necessary to conduct multicenter large sample studies to verify the effectiveness of a 17 value in PI risk assessments.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.1
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• pp.122-131
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• 1999

Indoor environments are usually less than optimal for the growth of ferns, especially in regards to the water condition. These studies were performed to investigate responses involved in causing growth of ferns and presume management plan against the water deficit under indoor conditions. The effect of air humidity and soil moisture on the ferns was examined in Adiantume raddianum and Selaginella kraussiana. Results of experiments are as follows; 1. Under a low humidity condition, having a 25-50% RH. ornamental value of ferns decreased much more than under a 90% RH. Under a low soil moisture, such as sand treatment, ornamental value of ferns also decreased. 2. Leaf chlorophyll content, water content and stomata situations increased as air humidity and soil moisture went up. 3. Even if air humidity and soil water were not enough for ferns growth, the extending of irrigation cycle was helpful. 4. Under extremely low air humidity conditions, some water management, namely, using water holding soil or extending of irrigation cycle was desirable. Other methods of increasing air humidity, including water instruments such as ornamental pools, waterfalls, or fountains, grouping plants together were also helpful. But spraying water on leaves increased injury to ferns growth because of excess evaporation from the leaves. Though these studies, we learn that ferns are susceptible to water condition such as air humidity, soil water and water management. If other environmental factos are maintained with optimal conditions, water condition plays an important role in ferns growth in indoor environments.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.1
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• pp.26-31
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• 1978

Effect of over flooding moisture levels on the growth and yield of barley and wheat crops was determined. The marked plant height retardation of barley under over saturated moisture treatment was observed at the elongating stage and wheat at the booting stage. The elongating and tillering stage subjected to over flooding moisture level significantly reduced panicle number and grain number per panicle, and 1000-grain weight reduction at the booting stage streated with over saturated moisture level. The highest yield reduction of two row and six row barley stage, under over flooting moisture level. Soil wet resistance observed in decreasing order; wheat<six row barley<two row barley.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.5
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• pp.369-382
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• 2017

Accurate and optimal water supply to cereal crop is critical in growing stalks and producing maximum yields. Recently, upland crops are cultivated in paddy field soils to reduce overproduced rice in Korea. In order to increase productivity of cereal crops in paddy fields which have poor percolation and drainage properties, it is necessary to fully understand crop response to excessive soil water condition and management of soil drainage system in paddy field. The objectives of this study were to investigate effects of excessive soil water to sesame growth and to quantify stress response using groundwater levels. Two cultivars of sesame were selected to investigate; Gunbak and Areum. These sesames were planted in paddy fields located in Miryang, Gyeongnam with different soil drainage levels and drainage systems. The experiment site was divided into two plots by drainage class; very poorly and somewhat poorly drained. Two different drainage systems were applied to alleviate excessive soil water in each plot: open ditch and pipe drainage system. Soil water contents and groundwater levels were measured every hour during growing season. Pipe drainage system was significantly effective to alleviate wet injury for sesame in paddy fields. Pipe drainage system decreased average soil moisture content and groundwater level during sesame cultivation. This resulted in greater yield and lignan contetns in sesame seeds than ones from open ditch system. Comparison between two cultivars, Gunbak had greater decrease in growth and yield by excessive soil water and high groundwater level than Areum. Seed components (lignan) showed decrease in seeds as soil water increased. When soil moisture content was greater than 40%, lignan content tended to decrease than ones from less soil moisture content. Based on these results, pipe drainage system would be more effective to reduce wet injury to sesame and increase lignan component in paddy field cultivation.