• Korean Journal of Organic Agriculture
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• v.19 no.2
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• pp.273-282
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• 2011

This study was conducted to investigate the effects of germanium (Ge) application types on the nutrient concentrations in soil and leaves and leaf characteristics in a 'Niitaka' pear orchard in 2004. Ge application included foliar application, fertigation in soils, trunk injection, and the three-combined application. All Ge treatedplots had lower soil $NO_3$-N, K, and Ca concentrations than those of control plot. Ge concentrations in Ge treated-soils were approximately 50 times higher than those of the control. Ge applications significantly increased area, dry weight, and specific weight in leaves compared to the control. Control treated-trees had greater K concentrations in leaves than the Ge treated-trees, which was oppositively observed for the leaf Ca; leaf Ca was higher on the Ge treated-trees than control. Leaf Ge concentrations were significantly higher on the Ge treated-trees compared to the control, except for the Ge fertigation. Ge concentrations in fruits were greater on the Ge-treated trees than the control trees.

• Korean Journal of Organic Agriculture
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• v.11 no.2
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• pp.91-101
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• 2003

This study was tried to examine the efficacy of apples that had grown with agro-chemical alternatives in an apple orchard. The chlorophyll content of apple leaves was a little higher in the plot of Charcoal powder, Chitosan, and Peat moss treatment among the other agro-chemical alternatives. On the contrary, the sugar content of apple fruits was higher in the plot of Amino acids, and Green ion calcium treatment, but there was quite a difference among them. Vitamin C content of apple fruits was high at the cell division period. It became lower at the hypertrophic period and then got higher again at the harvest. Vitamin C content was the highest in the chemical fertilizer plot as well. In an apple orchard where agro-chemical alternatives were used only, the commercial grade of ripened apples had declined by 25％, compared to those in customary cultivation. The commercial grade of ripened apples with agricultural chemicals using fertilizers and pesticides was over 90％ with over 250g of its weight in the plot of Charcoal powder, Amino acids, and Vitamin C treatment. Therefore. we guessed the environment-friendly method of cultivation in an apple orchard shall be established by reducing the usage of agricultural chemicals gradually and increasing the agro-chemical alternatives at the same time.

• Korean Journal of Food Science and Technology
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• v.5 no.3
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• pp.178-182
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• 1973

Omija (Schizandra chinmensis Baillon) grown widely in Korea has been used as a traditional drink and as an ingredient in herbal medicine. A determination of the proximate composition, organic acids and major anthocyanins in Omija was made. 1. The proximate composition of Omija showed water to be 84.2%, protein to be 1.1%, fats to be 0.9%, reducing sugars to be 10.9% and total anthocyanins to be 0.2% in terms of weight percent of fresh, ripe Omija 2. Gas chromatography showed citric acid(3.5%), malic acid(1.4%) and succinic acid(0.2%) to be the major organic acids of the fruit. 3. The anthocyanins, the major pigments present in Omija were separated and isolated into 3 fractions using column chromatograph on insoluble polyvinylpyrrolidone. The main anthocyanin was tentatively identified as peonodin 3-glucoside on the basis of its absorptive properties before and after treatments with acid and $AlCl_3$ in the UV and visible ranges.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.3
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• pp.241-248
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• 1995

This experiment was conducted to obtain basic information for the management of soil and fertilization for plastic-house soil cultivated Khwari green pepper in Dang Jin area of Chung Nam Province. The range of pH with highest frequency for 36 sites investigated was 6.1~6.5, OM 1.6~2.5%, available phosphorous 601~800mg/kg, CEC 12.1~14.0 c mol/kg, clay 16.1~18.0% and below 2.0ds/m for electical conductivity of soil. Fesh fruit weight of green pepper showed very high significant positive correlation with organic matter, clay content and cation exchange capacity, while negaive correlation with electrical conductivity. Electrical conductivity showed highly significant negative correlation with CEC, clay content and organic matter in soil, respectively. To decrease below 2.0 dS/m of electrical conductivity in plastic-house soil, the content of clay and organic matter could be maintained at above 1.8% and 2.3%, respectively.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.149-159
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• 2017

This study was conducted to develop an organic control method of tobacco whitefly (Bemisia tabaci) by using cooking oil and yolk mixture (COY). Mortality rate against B. tabaci nymph on paprika leaf was 94.5% by COY treatment and it was not significantly different from that by pyridaben treatment. Mortality rate against B. tabaci nymph on tomato leaf was 41.4% by COY treatment and it is lower than that by neem extract. But mortality rates of B. tabaci adult by COY and neem extract were no significant differences. Oviposition of B. tabaci were decrease respectively 75.8% and 52.7% by COY on paprika and tomato leaves. In paprika and tomato greenhouses, damaged by B. tabaci, COY was sprayed twice and resulted in respectively 100% and 38% control values.

• Korean Journal of Organic Agriculture
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• v.20 no.3
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• pp.411-422
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• 2012

To investigate the possibility of sustainable agriculture in no-tillage pepper this study was carried out in vinyl greenhouse with organic cultivation having no pesticide certification. 1. Growth and yield in pepper cultivation General growth in pepper was suppressed with decreasing hill spacing, primary branch length, and stem width. Fruit diameter and fruit weight in no-tillage increased significantly, and yield of pepper increased by 10% compared with conventional tillage. From results organic cultivation in no-tillage improved a quality of pepper compared with conventional tillage. 2. Production cost of conventional tillage and no-tillage Production cost of conventional tillage and no-tillage was not different in seed cost, inorganic fertilizer cost, pesticide cost, repair cost, light agricultural tool cost, agriculture facilities depreciation cost and so on. Intermediary goods cost in no-tillage was decreased by 11% for organic fertilizer cost, light and heat expenses and power rate, heavy agricultural tool cost, and repairing expenses compare with conventional tillage. Employment effort cost and work effort cost were decreased, and farm income and farm income rate were increased by 11% and 5%, respectively, in no-tillage. In this work, yield and gross income were increased by 10% and 25%, respectively, in no-tillage. Therefore material cost, intermediary goods cost, working expensive, farm income, and income rate were increased by 34%, 3%, 2%, 52% and 22%, respectively.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.773-786
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• 2016

Grape cultivar "Campbell Early" account for 70% of table grape in Korea and Leaf Spot Disease caused by Pseudocercospora vitis is one of a major disease in greenhouse and field grown area during late summer season in both of organic and conventional grape farm. Leaf spot disease can cause lowing of sugar content in fruit and vine growth and very difficult to control especially in organic field. Photosynthesis ability and chemical components are compared between leaf spot disease infected leaves with degree of necrotic area. With increase of disease necrotic area, $CO_2$ differential value, water use efficiency and $CO_2$ assimilation and respiration ratio are decreased proportionally and on the other hand, stomatal conductance value is not affected by disease necrotic area. Chlorophyll contents are also decreased by 50% in heavily infected leaves and imply decrease of chlorophyll contents is a major source of photosynthesis ability decline. With increase of disease necrotic area in leaves, total nitrogen and phosphate contents are decreased and on the other side, total carbon, potassium, calcium and magnesium contents are increased. From this research, we can infer that not only chemical control program is important in control of leaf spot disease but also fertilizing program is significant especially in organic agronomical control of fungal disease in grape cultivar "Campbell Early".

• Applied Biological Chemistry
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• v.38 no.4
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• pp.340-344
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• 1995

Banana purchased from local market was stored at 5, 15 and $25^{\circ}C$ for 10 days after which free sugars and organic acids were determined. The amount of glucose, fructose and sucrose was $0.30{\sim}0.36%$ at the initial time of storage. The changes of free sugar was influenced by storage temperature. At $5^{\circ}C$, little change in the content of each free sugar was measured and sucrose had a slightly higher value. Glucose and fructose showed a predominant increase while sucrose content decreased at 15 and $25^{\circ}C$. The values of total sugar, reducing sugar, glucose, fructose and free sugar contents at $25^{\circ}C$ were higher than at any other storage temperature. Citrate, malate, lactate and acetate in Banana were identified as organic acids. The total amount of organic acid decreased from $305{\sim}373.3$ mg% at the initial time to $45.9{\sim}67.9$ mg% after 9 days of storage. The reduction of organic acids contents was relatively high at $25^{\circ}C$.

• Research in Plant Disease
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• v.13 no.3
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• pp.157-163
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• 2007

Hot water treatment that is the most appropriate seed disinfection method for organic vegetable farming was evaluated in this study. Among the leafy vegetable seeds lettuce that was the most sensitive to hot water was suitable to treat at $45^{\circ}C$ for 25 min, while Chinese cabbage and radish seeds were optimally treated at $50^{\circ}C$ for 25 min. The treatments resulted in similar or higher seed germination rate than non-treated seeds and promoted plant growth. In addition, fungi such as Alternaria, Aspergillus, Penicillium, or Mucor grown on the seeds were suppressed over 90% and the bacterial growth on lettuce seeds reduced 98.5% by the treatment. Among the fruit vegetable seeds pumpkin that was vulnerable to hot water was suitable to treat at $50^{\circ}C$ for 15 min, while cucumber and hot pepper seeds revealed optimum treatment at $50^{\circ}C$ for 25 min as chinese cabbage and radish. The treatment also showed similar or higher seed germination rate and growth than non-treated seeds. Furthermore, fungi such as Rhizopus, Aspergillus, Penicillium or Mucor grown on the seeds reduced from 72.0% to 95.4%. The bacterial growth on cucumber and red pepper seeds was suppressed from 65.5% to 86.0% by the treatment. Results indicated that the hot water treatment is practical for disinfection of organic vegetable seeds and the optimum temperature and soaking time varied among the seeds.

• Korean Journal of Organic Agriculture
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• v.7 no.1
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• pp.35-48
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• 1998

The total amount of dry matter for the green manure crops was great wheat> rye> barley> Italian ryegrass in that order. The green manure crope were verified to have the reducing effect of injury of successive croppingin peper, mainly reducing the occurance of the most important pepper disease, Phytophthora capsisi, and enhancing the pepper quality in the fruit length and diameter. The direct seeding using current commercial pepper variety was proved as not economical one. In the first year of compost application, the growth and yield of red pepper were rather somewhat decreasing compared with those of check plot applied with organic fertilizers. compst application increased the content of organic matter in soil, which suggested compost could be applied for the sustainable purposes. In preference analysis about taking the new technique, the smaller farmer's cultivation area the more they wanted to accept the LISA farming, compared with the conventional one, could be possible to save 12% in the inorganic fertilizer expenses but wasted 412% ant 163% in both organic fertilizer and operator labor expenses, respectively. At the same time, the LISA decreased 15% in production cost but increased 225% and 139% in organic fertilizer quantity and operator labor hours. Since there was a great deal of difference in technological and economic factors from two farming methods, LISA multi-goal decision modeling is further required.