• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.1
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• pp.18-28
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• 2021

The growth period and productivity of cropping system of winter wheat-rice, winter wheat-bean and winter wheat-grain corn for 4 years from 2015 to 2018 were compared at the experimental field of National Institute of Crop Science in Miryang city. The harvest period of winter wheat was in mid-June, and summer crops were sown (transplanted) in late June. In transplanting of rice in late June, there was no difficulty in securing the heading of panicle and the yield of rice, but there was a lot of trouble in sowing wheat in proper time because the harvest time of rice was delayed to early November due to late maturity of rice, particularly in the mid-late maturing cultivar. There was no problem in soybean planting after winter wheat because the proper period of soybean planting is late-June. In addition, there was no problem in winter wheat sowng after soybean because the maturity period of soybean was mid-October. Selection of grain maize in double cropping with winter wheat in terms of growing periods, was desirable because grain maize had the fastest maturity among summer crops. In double cropping of winter wheat-summer crops, wheats combined with soybean and grain maize showed stable yields during three years, but there was a risk of yield declines in the wheat combined with rice in heavy rainfall year. It was possible to secure high yields in three summer crops as yields of rice, soybean, and corn were 600, 350, and 800 kg/10a, respectively. Summer crops with medium maturity was recommended because of no significant difference in yield between medium maturity and medium-late maturity cultivar. Soil physical properties were improved in soils cultivated with soybean and grain maize. Therefore, It was thought that double cropping systems of winter wheat with soybean and grain maize were superior to that of winter wheat with rice in terms of connecting period between winter wheat - summer crops and improvement of soil physical properties, and total income, particularly in soybean.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.81-87
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• 1968

It has been made clear that there exist a definite rhythm in the accumulative process of carbohydrates of soybeans, and that there is a great variation in nitrogen metabolism. In spite of earlier or later manuring, it is possible to make use of the above stated conclusion. But in the case of later manuring, there is so short a time of growth before harvest, resulting in the lack of normal growth and in a great effect upon harvest. In the general terms, the first half period of growth may be called that of nitrogen assimilation, and the late half, that of carbohydrate assimilation. It has delayed comparatively distinction between these periods whether manuring was done earlier or later. In other words, the lack of carbohydrates in the first half period of growth has been found to deter the process of protein synthesis. And the lack of protein in a body in the latter half period of growth has been found to weaken photosynthesis that should be active, resulting in the decrease of harvest. Consequently, lack of protein in the body during the period of pod adhesion definitely brought about lack of growth in the latter period of growth. It follows, therefore, that in order to increase harvest, it is necessary to manure comparatively in the early period, and that contents of various forms of nitrogen.

• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.211-217
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• 1996

As a part of studies on the development of a Gugisuen(Lycium chinense M.), which is one of the unutilization of waste resources, we investigated the composition of fatty acid and amino acid according as picking period and varieties of Gugisuen. The chemical components of Gugisuen were as follows : 1. Proximate composition of Gugisuen were Cheongyang native had the highest contents of crude lipid, crude protein, total sugar, and the contents of crude protein, total sugar, and reducing sugar was the highest picked on June 20. 2. The contents of $P_2O_5$, $K_2O$, CaO, MgO, Cu, and Mn were higher in Cheongyang native than that of other varieties. And mineral contents of Gugisuen picked on May 10 were the highest. 3. The major fatty acids were linoleic, linolenic acids, and these unsaturated fatty acids composed about 50% of total fatty acids. Fatty acid compositions between each varieties were not significant, and those components were the highest in Gugisuen picked on May 10. 4. Eighteen amino acids were identified from Gugisuen, glutamic acid, the highest content was $10.05\sim10.94%$ and these contents increased in the order to aspartic acid > glycine > alanine > leucine > lysine. The contents of serine, arginine, methionine, cystine-2 and isoleucine were higher in late harvest time and glutamic acid and tryptophane were higher in early harvest time.

• Applied Biological Chemistry
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• v.43 no.2
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• pp.106-109
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• 2000

In order to determine the optimum harvest time of Acanthopanax koreanum Nakai, free sugars, organic acids, amino acids and minerals were investigated. Ash, crude fat and crude protein of 4-age's tree of Acanthopanax koreanum were $2.98%{\sim}3.90%,\;1.93%{\sim}2.34%,\;3.52%{\sim}4.23%$, respectively. Minerals were 835.9 mg/100g of K, 971.3 mg/100g of Ca, 168.7 mg/100g of Mg, 38.8 mg/100g, of Na, 18.6 mg/100g of Fe, and 8.5 mg/100g of Cu on average, respectively. Calcium content was increased distinguishably as late as harvest time, especially in stem and root. Glucose, fructose and sucrose content of stem were $0.71{\sim}0.75%,\;0.31{\sim}0.03%,\;and\;0.16{\sim}0.21%$, respectively. Organic acid was $381.0\;mg/100g{\sim}504.9\;mg/100g$, and was mainly consisted of succinic acid, citric acid and malic acid. Twelve kinds of free amino acids were detected. Total amino acids was $33.56\;mg/100g{\sim}48.60\;mg/100g$, and it was the highest on samples harvested at September. Arginine, phenylalanine and glutamic acid were the main free amino acids of stems.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.3
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• pp.285-292
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• 2012

This experiment was carried out to determine the harvesting day after heading of barley for highest total forage yield in double cropping with corn at paddy field in middle region. The fresh barley yield was the highest at the harvest of 20 days after heading, but the dry matter yield and TDN yield were the highest at the harvest of 25 days after heading because of higher dry matter rate. The dry matter yield of corn after the harvest of 25 days after heading was decreased about 16 percent than that of the check, sowing on april 25. But total fresh yield of corn monoculture was lower about 31 percent, and decreased 28 percent of dry matter and 23 percent of TDN yield, respectively, than that of the double cropping system with corn and barley. In double cropping system at paddy field, the total forage yield was the highest at the harvest of 25 days after heading of barley and grew corn subsequently. Although yield of corn was reduced by late sowing, the total forage yield was increased by double cropping system compared with corn monoculture.

• Korean Journal of Environmental Agriculture
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• v.39 no.4
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• pp.360-367
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• 2020

BACKGROUND: The productivity and quality of blueberry (Vaccinium ashei Reade) greatly depend on the number of fruits in a plant. Especially, fruit set more than appropriate number negatively affects productivity and marketability due to the increased number of small fruits and delayed harvest time. This study was conducted to investigate proper timing and concentration for applying chemical blossom thinners such as ammonium thiosulfate (ATS) and UREA. METHODS AND RESULTS: ATS at 1.25% and 1.50%, and UREA at 6% and 8% were applied in four developmental stages, bud swell, pink bud, full bloom and petal fall. Fruit thinning rate was calculated based on the number of fruits harvested divided by that of flowers before applying blossom thinners. Ratios of leaf to flower and leaf to fruit were calculated based on the number of fully developed leaves in 25 days after full blossom divided by that of flowers or fruits, respectively. Chemical injury of leaves was investigated by calculating the number of leaves with chemical injury divided by the total number of leaves. Fruit thinning rates were 48% and 66% for UREA treatments at 6% and 8%, respectively, and 49% and 62% for ATS treatments at 1.25% and 1.50%, respectively, in the full bloom stage. In the petal fall stage, fruit thinning rates were 18% and 24% for UREA treatments at 6% and 8%, respectively, and 49% and 35% for ATS treatments at 1.25% and 1.50%, respectively. Leaf to fruit ratio (L/FR) increased by 109% and 188% compared to leaf to flower ratio in ATS treatments at 1.25% and 1.50%, respectively, and L/FR increased 93 and 196% in UREA treatments at 6% and 8%, respectively, in the full bloom stage. In the petal fall stage, leaf to fruit ratio increased by 60% to 100% in ATS treatments, but did not significantly differ from the control in UREA treatments. Fruit harvest was delayed in all treatments of all developmental stages except for 1.5% ATS and 6% UREA treatments at the petal fall stage, whose fruit harvest was two or three days faster than the control. CONCLUSION: The application of ATS and UREA for blossom thinning should be in the petal fall and full bloom stages for early and late harvest, respectively. Considering chemical injury, integrated harvesting and fruit size, however, it is appropriate to apply ATS at 1.5% in the petal fall stage to increase fruit productivity and quality in blueberry.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.4
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• pp.335-340
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• 1989

In order to find out the optimum harvest (clipping) date combined with sowing date on yield and nutrient Quality of forage rape which is suitable at the southern part of Korea, Velox, introduced variety was grown from Sep. 1987 to May 1988 at Sunchon National University, and yield and nutrient Quality of plant were observed. As harvest date and sowing date were delayed, the plant length was longest, number of branch and leaves per main stem were increased in the time of full bloom clipping and Sep. 24 sowing but stem diameter was thickest in the early sowing. Fresh yield was heaviest in the time of flowering clipping and Sep. 24 sowing but the most dry matter yield was heaviest in the time of full bloom clipping and Sep. 24 sowing. Content of crude protein was highest and that of crude fiber such as NDF, ADF, hemicellulose, cellulose and lignin were lowest in the late time of clipping and sowing. Further more IVDMD was high and dry matter yield and digestible dry matter yield were highest in the time of flowering clipping and Sep. 24 sowing. Judging from the results reported above, at optimum harvest (clipping) date combined with sowing date for yield and nutrient Quality of forage rape seemed to be the time of flowering clipping and Sep. 24 sowing.

• The Plant Pathology Journal
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• v.17 no.1
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• pp.40-44
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• 2001

Disease occurrence and development of gray blight of tea (Camellia sinensis) were investigated. Higher incidences and more severe damage by gray blight were found in Japanese tea variety Yabukita than the Korean local variety. In Yabukita, Pestalotiopsis longiseta was more frequently observed on the diseased leaves than P. theae but vice versa in the Korean local variety. This indicates that there was the varietal difference in the distribution of fungal species of gray blight pathogens. Both varieties were most severely damaged during the third harvest period with weather conditions of high temperature and humidity favorable to the disease. Presence of the tea brown blight fungus Glomerella cingulata on the margin of gray blight lesion at the late stahe suggested that the pathogenic fungi of tea gray blight were replaced by the brown blight fungus during the disease development.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.3
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• pp.201-206
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• 2004

This experiment was performed to evaluate the agronomic characteristics and dry matter yields of the early maturing cultivars(c.v.'Koolgrazer', '9909,' 'Ol-homil' and 'Jlee select') the medium maturing cultivar(c.v. 'Homil 22') and late maturing cultivars(c.v. 'Danko', 'Kior', 'Amilo' and 'Spooner'.) Seeds were sown on October 3, 2002 and October 8, 2003, respectively at the Livestock Experiment Farm of Keimyung College, Seongju, Kyeongbuk Province. Forage rye was harvested on April 22, 2003 and April 23, 2004, respectively. The height of early maturing cultivars were higher than that of late maturing cultivars at the harvest. Fifty percent heading date of the early maturing cultivar was on April 14 and that of late maturing cultivars were on April 24. In the first year, dry matter(DM) yield of 'Jlee select' was significantly the highest in among all cultivars(p < 0.05). DM yield of early maturing cultivars were higher than that of medium and later maturing cultivars. In the second year, DM yield of '9909' was significantly the highest in among all cultivars(p < 0.05). The early maturing cultivar of 'Koolgrazer' and 'Ol-homil' were similar and 'Jlee select' was low, late maturing cultivar of 'Danko', 'Kior', 'Amilo' and 'Spooner' were lower than early maturing cultivar. According to the results obtained from the study, it is suggested that the early maturing cultivar would be recommendable for fall sown rye for double cropping forage production.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.1
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• pp.49-58
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• 2003

This study was conducted to determine the effect of seeding times and mixture rates of oat and forage rape on the growth characteristics and forage yields during rest periods from March to June after the harvest of potatoes in potato cultivation fields located in the areas about 600m above the sea level in Jeju. The experiment was a split plot desist with seeding times(early, middle and late March) sown . at intervals of ten days from early March to late March as the nam plots and mixture rates as subplots, consisted of oat single(150kg/ha), forage rape single(15kg/ha), oat/rape mixtures 75 : 25% (112.5kg/ha of oat and 3.75kg/ha of rape), oat/rape mixtures 50 : 50％(75kg/ha of oat and 7.5kg/ha of rape) and oat/rape mixtures 25 : 75％(37.5kg/ha of oat and 11.3kg/ha of rape). The germination and establishment of eat and rape were not significantly different among seeding times and mixture rates. The plant heights were higher when seeded middle March compared to seeding times of early and late March. The growth stage of the oats seeded early March was dough stage, while that of oats seeded middle or late March was milk stage. The dry matter yields per ha were higher(p<0.05) when seeded middle March than those of seeding time of early and late March. The crude protein contents of rape single, mixtures and oat single treatments were 15.9, 12.4∼14.5 and 8.5％, respectively.