• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.377-381
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• 2010

This study was carried out to access the stauts of pyruvic acid and sugars in onion bulbs during storage at room temperature. Pyruvic acid content remained in a steady state until 3 months of storage. However the pyruvic acid content gradually increased as the onions started to root, and rapidly increased after sprouting. There was no difference in dry matter contents during storage.e. Sucrose content increased as storage duration extended, and then gradually decreased right after the onions started to sprout. Fructose content gradually decreased after 45 days of storage, and remained in a steady state after sprouting. Glucose content had a tendency to increase as storage duration extended. Pyruvic acid/total sugar (PA/TS) ratio decreased after 1 month of storage, and then increased after 135 days, and was 83% higher at 150 days of storage than at harvest. Sweetness gradually decreased until 1 month of storage, but thereafter remained steady. Therefore it is desirable that pyruvic acid analysis for sweet onion selection should be conducted before breaking the dormancy.

• Korean Journal of Environmental Agriculture
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• v.2 no.1
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• pp.1-5
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• 1983

A study was undertaken to investigate the persistence of diazinon in two different soils under field conditions. Half-life of diazinon granule(5%) incorporated into soils at a rate of 0.15 ㎏ a.i./l0a was 11 and $9{\sim}12$ days in Suweon and Iri soil under field conditions, respectively. Diazinon residues in brown rice and rice straw harvested from Suweon field were also evaluated by scheduled application intervals. On the basis of maximum residue limit of diazinon in brown rice, it is recommended that the insecticide could be applied upto 15 days before harvest at the limit of 4 spraying times.

• Journal of Bio-Environment Control
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• v.10 no.3
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• pp.155-158
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• 2001

The cultivation area of white spined cucumbers for export has continuously increased up to 121 ha in 2000. Since white spined cucumbers set fruits on lateral shoots, fruit yield is dependent upon the development of lateral shoots. Unfortunately, the major cultivation period is during winter season, October to February, when temperature and light are limited for the development lateral shoots. This experiment was conducted to investigate the effect of soil heating on the development of lateral shoots in white spined cucumbers. Number of lateral shoots were 13.7 and 11.7 in the soil heated treatment and in the control, respectively. Number of marketable fruits per plant was 45 in the soil heated treatment as compared to 38 in the control. Fruit yield was 81 ton per ha, an 18% increase, in the soil heated treatment. Soil heating not only increased number of long lateral shoots but also decreased curved fruits.

• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.146-150
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• 2000

This study was conducted to investigate the effect of seedling age on quality and yield in bag culture of sweet pepper. Seedlings of 20, 30, 40, 50, and 60 days old were compared. 60 days old seedlings grew faster than 30 or 40 days old seedlings. Mean days to bloom after sowing was fastest as 48 days in 30 days old seedling, followed by 20 days old seedlings. Rot activity was higher in 20 or 30 days old seedlings. Number and length of first lateral roots with thickness of 1.5mm or less, reached to 106.5 and 1.085 cm, respectively in 30 days old seedlings. Root weight, root length, and number of primary lateral roots were the greatest in 30 days old seedling. Greater early yield a obtained in 50 and 60 days old seedling, while late yield was grater in 30 or 40 days old seedlings.

• Korean Journal of Agricultural Science
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• v.29 no.1
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• pp.15-23
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• 2002

The percentage of watercore occurrence harvested on Nov. 6 (commercial harvest season) was over 80% but fruits seemed not to reach climacteric stage on the basis of ethylene evolution. The occurrence ratio and severity of watercore gradually decreased with the increase of preshipment storage for 2 months. The level of soluble solids did not show a clear tendency during preshipment storage but flesh firmness, fresh weight, and acidity gradually decreased. Although the overall quality of fruit reduced along with the increase of preshipment storage duration after exposure to retail condition at ambient temperature for 1 week, plastic film wrapping (PE 30 um) as well as plastic film wrapping plus ethylene scrubbing had a benefit on keeping freshness of fruit even after retail condition. Waxed fruit showed excellent appearance but browning disorder was developed. Results indicated that moisture barrier such as plastic film wrapping and ethylene removal have a great potential on keeping freshness of fruit during export which required long-term transport under low humidity environment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1776-1783
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• 2016

Onions cultivated with (SY) or without (SN) sulfur application were stored for up to 36 weeks at $4^{\circ}C$ since harvest, after which they were analyzed for chemical composition and antioxidant activity in relation to sulfur (S) application and storage duration. Compared with SN onions, SY onions showed lower moisture and higher protein, soluble solids, and flavonoid contents at the time of harvest, and moisture and protein contents remained the same until 20 weeks of storage. However, soluble solids decreased while antioxidant activities, including flavonoids content, total reducing capacity, and superoxide dismutase (SOD)-like activity, appreciably increased as storage time increased to 20 weeks, which could be attributed to onion respiration and protective response to environmental stresses, respectively. There were abrupt decreases in flavonoid content and SOD-like activity at 36 weeks, presumably due to severe deterioration. Interestingly, all phenomena observed depending on storage time were independent of S application of onions. The results show that the critical factor influencing the chemical composition and antioxidant activity of onions during storage was postharvest storage duration rather than S application during onion cultivation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.142-150
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• 2020

This experiment was conducted to set ideal harvest time for itallian ryegrass (IRG) seed in reclaimed land. For IRG 'Kowinearly' variety sown in both autumn and spring, the peak growth in reclaimed land occurred in 20-30 days after heading. Plant height of IRG seedings in the spring was 90.4% of the fall-sown's plants. The yield of IRG seeds in reclaimed land was generally lower than that of farm land due to poor growth conditions. After heading, the lodging and shattering increased gradually with time. The highest yield of seed in the fall-sown trial treatment was 238 kg/10a. However, in the spring-sown treatment, the highest yield reached 169 kg/10a, which was 71% that of the fall-sown treatment. To set optimum harvesting time for IRG seed, morphological changes in the plant, moisture content of seed, and germination rate were analyzed according to time series after heading. After heading, IRG stem color had turned pink in 18 days and seed color also changed after 20 days. Following 20-25 days after heading, the seed moisture content decreased to below 55% and germination rate increased to over 90%. Therefore optimum harvesting time for IRG 'Kowinearly' variety in reclaimed land was 20-30 days after heading because germination rate and yields were high and shattering percentage was low.

• Korean Journal of Medicinal Crop Science
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• v.9 no.1
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• pp.1-7
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• 2001

This experiment was carried out to investigate the effects of shading treatments and harvesting methods on the growth of Eleutherococcus senticosus, which was known as the medicine of anticancer, anti-stress, hepatic detoxification activity, immunoactivity, and tonic. Light transmission ratio and air temperature were decreased as $40{\sim}64%$,$1.9{\sim}2^{\circ}C$, respectively, in 30% to 70% shading net treatment compared to non-shading. Fifty percentage shading net treatment was effective for the growth and yield of Eleutherococcus senticosus. During summer Eleutherococcus senticosus was growing under shading net treatment compared to non-shading. Tunnel type was more effective for growth than vertical type in shading method. 30cm length included 2 to 3 nodes cutting from soil surface was the most effective for branching stem length, plant height and yield as harvesting methods.

• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.672-679
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• 2006

Postharvest nut quality, and changes of soluble solids content and kernel hardness during cold storage in 13 Korean prevailing chestnut cultivars were investigated to establish the chestnut grading and standardization for marketing and processing industry. Chestnut quality attributes such as nut weight, soluble solids content, kernel hardness, % with the pericarp split, and % of polyembryonic nuts were measured from 2001 to 2005. There were significant difference among cultivars in quality characteristics, and also annual variation within same cultivar, corresponded to the high genetic and environmental variability. During cold storage at $2^{\circ}C$ for 16 weeks, remarkable changes in soluble solids content were observed, and Isseumo showed the highest increase of 8% at 16 weeks of cold storage compared with postharvest. In case of most cultivars except early ripening cultivars, soluble solids content of chestnut increased until 12 weeks during cold storage, followed by decreased gradually thereafter. Kernel hardness of most cultivars except lshizuchi during cold storage increased slightly, but it was not statistically significant. This work would be a useful reference to the quality of each chestnut cultivar for the growers and breeders alike.

• Horticultural Science & Technology
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• v.19 no.2
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• pp.140-144
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• 2001

Field investigations were initiated to determine possible new 'ssam' vegetable that could be grown during the summer season in highland. Korean 'ssam' means cooked rice in vegetables. The 'ssam' vegetable is called that those leaves has been used for wrapping at meal. Seventeen leafy vegetables were studied, including chard (Beta vulgaris L. var. flavescens DC.), leaf broccoli (Brassica oleracea L. var. italica), Chinese leek (Allium tuberosum Rottl.), Japanese hornwort (Cryptotaenia japonica Hassk), red leaf mustard (Brassica juncea L.), green leaf mustard (Brassica juncea L.), leaf parsley (Petroselinum crispum Nijim), pakchoi (Brassica campestris L. ssp. chinensis Jusl.) tatsoi (Brassica campestris var. narisoma), kale (Brassica oleracea var. acephala), collard (Brassica oleracea var. acephala), Korean mint (Agastache rugosa O. Kuntze), romaine lettuce (Lactuca sativa L. var. longifolia Lam.), red leaf chicory (Cichorium intybus L. var. folisum), red chicory (Cichorium intybus L. var. folisum), green leaf chicory (Cichorium intybus L. var. folisum), and sprouting broccoli (Brassica oleracea L. var. italica). Date of the first harvest in 1999 was July 10th in chard, leaf broccoli, red mustard, mustard, leaf parsley, pakchoi, tatsoi, kale, collard, Korean mint, red leaf chicory, red chicory, green leaf chicory, and sprouting broccoli. Date of the first harvest for Chinese leek, Japanese hornwort, and romaine lettuce was from the middle of June to the late of August. Based on ratings on marketable yield, we found good leaf shape, taste and yield in chard, red leaf mustard, green leaf mustard, pakchoi, tatsoi, romaine lettuce, red leaf chicory, red chicory, and green leaf chicory. Even though the most of all these vegetables were obtained high scores by test panels in shape, taste and quality, but some of them revealed inadequate leaf size as a 'ssam' vegetable. That problem will be solved by control of harvesting time. On the basis of this observation, chard, red leaf mustard, green leaf mustard, pakchoi, tatsoi, romaine lettuce, red leaf chicory, red chicory, and green leaf chicory were rated as promising 'ssam' vegetable by analysis of profits, adaptation, and quality.