• Food Science and Preservation
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• v.8 no.1
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• pp.66-73
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• 2001

This study was carried out to know whether $\beta$-galactosidase is directly important or not on fruit softening during the development of peach fruits compared to those in the stage stage. It was investigated that the flesh firmness, cell wall components, and the glycosidase activities of the peach fruits with a fast softening cultivar, 'Mibeakdo', a slow softening cultivar,'Yumyung'and a middle softening cultivar, 'Okubo$\beta$, at different developmental stages, on 13 May, 16 June, 16 July, and 5 August and on 28 August which harvested only 'Yumyung' fruits. In order to investigate the amounts of total sugar and non-cellulosic neutral sugar, the cell wall materials of each fruit were solubilized in distilled water, 0.05M CDTA, 0.05M Na$_2$CO$_3$, 4% KOH, and 24% KOH sequentially. During the fruit development, the fruit firmness of three cultivars decreased and the fruit firmness of 'Yumyung' was higher than that fo 'Mibeakdo' and 'Okubo' in the overall period. During the fruit development, the changes of total sugar amounts of each measured fractions were similar among peach cultivars. Arabinose and galactose were the predominant non-cellulosic neutral sugars in all the fractions including cell wall material of the three cultivars. There was an active relationship between the changes of flesh firmness in three cultivars and the mol % changes of rhamnose on 5 August which was the harvest date of 'Mibeakdo' and 'Okubo' fruits. The activity of soluble $\beta$-galactosidase was high at the early developmental stage and then dropped to a very low activity level in all cultivars. The activity of cell wall-bound $\beta$-galactosidase was high at the early developmental stage and then decreased continuously through the harvest date. In addition the changes of other glycosidase activities were similar among cultivars.

• Journal of Bio-Environment Control
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• v.28 no.1
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• pp.9-15
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• 2019

This study aimed to examine the effects of different degrees of defoliation during harvest season on hydroponically cultured 'Seolhyang' strawberry's fruit characteristics, plant growth, and changes in nonstructural carbohydrates, and find an effective defoliation method. On November 29, 2013, some of the 'Seolhyang' leaves were non-defoliated and the others were defoliated remaining 9 and 5 leaves. The number of fruits and fruit weight were not significantly different in the first flower cluster but in the second, third, and fourth flower clusters decreased as the level of defoliation increased. The soluble solids content and acidity of fruits decreased in all the clusters as the level of defoliation increased. The leaf area and leaf dry weight of strawberry plant in all the treatment groups decreased from January to March and root dry weight sharply decreased during February. Thereafter, during April, the growth of plant increased. As defoliation increased, the dry weight of fruits, flower clusters, crowns, and roots decreased, and during late growing period, difference in dry weight according to the degree of defoliation was considerable. The content of carbohydrate was greater in the leaves than the fruits excepting January 30 and February 28, 2014 and in the case of strawberry plant that continuously produce fruits, the content of carbohydrate decreased in the leaves and roots. As defoliation increased, the content of carbohydrate in fruits, flower clusters, crowns, and roots decreased. Defoliation for strawberry plants is carefully done during harvest season. Twelve leaves during December and 14 leaves from January to March should be maintained, and in April when the number of leaves increases, old leaves should be defoliated.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.2
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• pp.182-189
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• 2015

Climate departure from the past variability was projected to start in 2042 for Seoul. In order to understand the implication of climate departure in Seoul for urban agriculture, we evaluated the daily temperature for the June-September period from 2041 to 2070, which were projected by the RCP8.5 climate scenario. These data were analyzed with respect to climate extremes and their effects on growth of hot pepper (Capsicum annuum), one of the major crops in urban farming. The mean daily maximum and minimum temperatures in 2041-2070 approached to the $90^{th}$ percentile in the past 30 years (1951-1980). However, the frequency of extreme events such as heat waves and tropical nights appeared to exceed the past variability. While the departure of mean temperature might begin in or after 2040, the climate departure in the sense of extreme weather events seems already in progress. When the climate scenario data were applied to the growth and development of hot pepper, the departures of both planting date and harvest date are expected to follow those of temperature. However, the maximum duration for hot pepper cultivation, which is the number of days between the first planting and the last harvest, seems to have already deviated from the past variability.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.271-276
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• 1998

This experiment was carried out to investigate the changes on nutrient uptake and yields of onion when it was applied with urea and ammonium sulfate as nitrogen fertilizer types; potassium chloride and potasssium sulfate as potassium fertilizer types and lime requirement and phosphorus absorption coefficient controlled 5% as soil improvement index. The variety of onion used was CheonJuHwang and the soil used was Yonggye series in the Jeonnam Muan area. The amounts of N, P and K uptake were higher in the mixed application plot of ammonium sulfate and potassium sulfate than in the plot of urea or potassium chloride. The sulfate content of soil was higher in the period of plant growth than in the harvest stage. The sulfate content of plant was highest in the harvest stage and this content was higher in the stem and in the leaf than in the bulb. The sugar content of onion was 7.43~8.23 Brix content was higher in the large bulb than in the small bulb. The weight of dry matter and the rate of good quality were high in the mixed application plot of ammonium sulfate and potassium sulfate, so the yield of onion was increased 2~6% compared with control.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.318-318
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• 2022

Basil(Ocimum basilicum L.) is an annual herb that grows wild in hot and humid regions such as tropical Asia and Africa. This study was carried out for resource discovery, propagation, and DB construction of aromatic plants. In order to evaluate the genetic characteristics, 28 kinds of basil seeds were supplied from the Center for Genetic Resources. For basil characteristics, planting date, plant height, growth shape, leaf length, leaf shape, petiole color, petiole, stem color, flower color, after harvest, Ml length including roots, flower length, stem thickness and biological weight were measured. For anthocyanin analysis, only basil with purple color was selected, anthocyanins were extracted with 60% ethanol containing 1% citric acid, a standard quantitative curve was prepared with cyanidin-3-glucoside, and absorbance was measured at 525 nm. Basil planting started around June 16, and the flowering period lasted for a total of 18 days from July 19 to August 5. On August 6, when flowering was completed, morphological characteristics including flower color were measured at the site by an object. The measured basil plant length was 26.6-59.6 cm, leaf length 2.0-7.9 cm, leaf width 0.7-5.2 cm, and petiole 1.3-3.9 cm. The growth pattern of basil was generally straight, medium in shape. The color of the leaves was observed evenly by mixed green, purple, purple and green, and the recesses in the shape of the leaf were also conspicuously observed. A total of three basil flower colors were observed: white, light pink(149P 10P/84), and purple(37V 2.5RP 4/12). During the second growth survey after harvest, the total length including the basil roots is 26.7-52.0 cm, the flower length is 8.2-29.3cm, the stem thickness is 7.1-15.9mm, the number of stem nodes is 3-12 nodes, and the total weight of the basil was measured to be about 218-1540 g. There are a total of 16 types of basil expressed in purple, and the anthocyanin content was measured to be 73.74 ~ 380.72 mg/100g.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.5
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• pp.71-79
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• 2016

The effects of spot heating for growing the strawberry cultivated in a plastic greenhouse during the winter that were estimated in Nonsan strawberry experiment station located in Chungnam. The temperature of water for heating was controlled by a electric hot water boiler and kept at the range of $22{\sim}24^{\circ}C$. Heating pipes were set up in root zone for root zone heating and very close to crown for crown heating. Spot heating effects were estimated by applying spot heating system in three test factors of heating root zone, crown only and crown plus root zone. The material for crown heating pipe was white low density polyethylene and the nominal diameter of that pipe was 16 mm. The material for root zone heating pipe was flexible stainless steel and the nominal diameter of that pipe was 15A. The flow rate of heating water circulation was 480 L/h and water circulation lasted for all day long. Temperatures, harvest yield by test beds were surveyed from Nov. 10, 2013 to Apr. 29, 2014. The temperature of crown spot for crown heating bed was at the range of $13.0{\sim}17.0^{\circ}C$ during the night and that of crown spot in control bed was at the range of $8.0{\sim}14.0^{\circ}C$. Also, the temperature of root zone for root zone heating bed was at the range of $18{\sim}21.0^{\circ}C$ and that of root zone in control bed was at the range of $13.0{\sim}15.0^{\circ}C$. The cumulative yield growth rate in earlier harvest period (from Dec. 20 to Mar. 15) of crown heating bed was 43% compared with that of control bed and the cumulative yield of crown plus root zone heating bed was 39 % and that of root zone heating bed was 39 %.

• Journal of Plant Biotechnology
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• v.39 no.4
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• pp.300-304
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• 2012

In order to research changes of asparagine content according to stage after harvest to storage, it was analysed asparagine content of potato tuber and potato sprout. The results of the asparagine content in potato cultivars after harvest ranked in cv. Superior, cv. Gahwang, cv. Atlantic and cv. Goun in descending order. The content of asparagine in potato was approximately 1300 mg/100g (D.W.) The changes the asparagine content according to storage condition and the difference of asparagine between tuber and sprout can be summarized as follows. In the asparagine content of potato cultivars, Little variation in the content was observed while potato tubers were stored at $4^{\circ}C$. However, after 3 months of storage at $10^{\circ}C$, the content increased by 9.7%, indicating that the content increases as the storage temperature and period increases. The content of asparagine also increased during sprouting of potato tubers. In the sprout, the proximal region contained 21% higher content of asparagines than the distal region, which suggests that the sprout develops with the increasing of the content of asparagines.

• Journal of Radiation Protection and Research
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• v.28 no.1
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• pp.9-18
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• 2003

Rice plants at different seed-developing stages were exposed to HTO vapor in an exposure box for 1 h during daytime and nighttime to investigate the levels of tissue free water $^3H$ (TFWT) and organically bound $^3H$ (OBT) in different plant parts. In the daytime experiment, TFWT concentrations in leaves at the end of exposure $(h_0)$ were around 100% of the 1 hour mean HTO concentrations in air moisture whereas in the nighttime experiment, they were as low as $30{\sim}40%$ of the air concentration. TFWT concentrations in both experiments decreased very rapidly in the beginning but much mote slowly later and those at harvest were hundreds to hundred thousands times lower than those at $h_0$. OBT concentrations varied with time in different manners depending on plant parts and exposure times and differed between at $h_0$ and at harvest by factors of less than 10 on the whole. Even during nighttime exposures, OBT was produced at about a third the rate for daytime exposures. The degree of the conversion of airborne HTO into OBT in mature rice seeds, being several times higher in the daytime experiment than in the nighttime experiment, was highest after the exposure peformed at the most actively seed-developing stage for both experiments. It is estimated that OBT would contribute much more to the ingestion radiation dose than TFWT if rice plants are exposed to HTO vapor for the seed-developing period.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2002.08a
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• pp.54-63
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• 2002

Post-harvest technology for rice was focused on in-bin drying system, which consists of about 100, 000 facilities in 1980s. The modernized Rice Processing Complex (RPC) and Drying Storage Center (DSC) became popular for rice dry, storage, process and distribution from 1990s. However, the percentage of artificial drying for rice is 48% (2001) and the ability of bulk storage is about 15%. Therefore it is necessary to build enough drying and bulk storage facilities. The definition of high quality rice is to satisfy both good appearance and good taste. The index for good taste in rice is a below 7% of protein, 17-20% of amylose, 15.5-16.5% of moisture contents and high concentration of Mg and K. To obtain a high quality rice, it is absolutely needed to integrate high technologies including breeding program, cropping methods, harvesting time, drying, storing and processing methodologies. Generally, consumers prefer to rice retaining below b value of 5 in colorimetry, and the whiteness, the hardness and the moisture contents of rice are in order of consumer preference in rice quality. By selection of rice cultivars according to acceptable quality, the periods between harvesting time and drying reduced up to about 20 days. Therefore it is necessary to develop a low temperature grain drying system in order to (1) increase the rate of artificial rice drying up to 85%, (2) keep the drying temperature of below 45C, (3) maintain high quality in rice and (4) save energy consumption. Bulk storage facilities with low temperature storage system (7-15C) for rice using grain cooler should be built to reduce labor for handling and transportation and to keep a quality of rice. In the cooled rice, there is no loss of grain quality due to respiration, insect and microorganism, which results in high quality rice containing 16% of moisture contents all year round. In addition, introducing a low temperature milling system reduced the percentage of broken rice to 2% and increased the percentage of head rice to 3% because of proper hardness of grain. It has been noted that the broken rice and cracking reduced significantly by using low pressure milling and wet milling. Our mission for improving rice market competitiveness goes to (1) produce environment friendly, functional rice cultivars, (2) establish a grade standard of rice quality, (3) breed a new cultivar for consumer oriented and (4) extend the period of storage and shelf life of rice during postharvest.

• Journal of the Ergonomics Society of Korea
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• v.36 no.5
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• pp.545-557
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• 2017

Objective: The aim of this study was to find risk factors in cultivating ginseng based on risk assessments and suggest safety measures for main risks. Background: Safety education and training is one of the practical and effective methods to prevent occupational accidents and injuries. In agricultural sector, there are few contents of safety education as compared to other industries. Especially, farm work has different cultivation characteristics according to the crops, so it needs special education materials for each crop. Among the various types of crops, ginseng contains various risk factors due to its long cultivating period and unique environment. Therefore, safety education material specified for ginseng is necessary to improve ginseng farmers' safety. Method: Risk assessment for cultivating tasks of ginseng was carried out through data obtained from various methods (site survey, interview, literature survey). To improve objectivity, the risk assessment was applied with 3-criteria (researcher estimate, interview, previous research results). Finally, the three high-risk tasks were selected and safety measures for those tasks were provided. Results: Three tasks, such as 'Mounting, maintenance and removing supports', 'Pest control' and 'Harvest', were selected as risky tasks among total tasks. (1) In 'Mounting' and maintenance and removing supports', the farmers found to be exposed to the risks of musculoskeletal disorders and accidents related to operating the tablet machine. (2) In 'Pest control', agrichemical poisoning, musculoskeletal disorders and hyperthermia were main risks. Finally, (3) In 'Harvest', the farmers are mainly exposed to the possibility of accidents of agricultural machines and risks of musculoskeletal disorders. Thus, it needs to apply appropriate safety measures to those risky tasks, such as safety guidelines, convenience equipment, protective kit, and so on. Conclusion: This study can be used as basic data for agricultural safety and expected that it would be useful for further study. In addition, the results of the research will be produced in the form of animation, which will enhance the safety consciousness for aged farmers. Application: The result of this study can be used in developing safety education materials for ginseng farmers which is essential to prevent occupational accidents and injuries among ginseng farmers.