• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.148-158
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• 2009

We tested and selected some agrochemicals reducing the occurrence of major pests and diseases during garlic storage. Tebuconazole, diphenylamine and prochloraz as fungicides and dimethate as a insecticide were sprayed or drenched before harvest. And the harvested garlic was dipped in each of the agrochemicals. The residues of pesticides in garlic bulbs treated were analyzed every month from harvesting time for 6 months. In case of Danyang garlic, which was treated with pesticides before and after harvesting, the residues of diphenylamine, tebuconazole, prochloraz, and dimethoate ranged from 0.008 to 0.28, from 0.03 to 0.32, from 0.02 to 0.12, and from 0.02 to 0.25 mg/kg, respectively. In case of Uiseong garlic, the residues of diphenylamine, tebuconazole, prochloraz and dimethoate ranged from 0.008 to 0.09, from 0.08 to 0.45, from 0.02 to 0.57, and from 0.04 to 0.38 mg/kg, respectively. And, in case of Namdo garlic, the residues of diphenylamine, tebuconazole, prochloraz, and dimethoate ranged from 0.008 to 0.52, from 0.07 to 1.67, from 0.02 to 0.17, and from 0.03 to 0.73 mg/kg, respectively. Some of the garlic samples treated with tebuconazole exceeded its maximum residue limits (MRLs) of 0.1 mg/kg set by Korea Food Drug Administration (KFDA), but dimethoate was detected below its MRL of 1.0 mg/kg. In case of diphenylamine and prochloraz, their MRLs for garlic were not set. Adapting their MRLs, 5.0 mg/kg of diphenylamine for apple and pear and 0.5 mg/kg of prochloraz for strawberry and grape, residue levels of diphenylamine and procloraz were below than their MRLs, with the exception of samples two times treated with procloraz in Namdo garlic. These results indicate that dimethoate can be used as an agrochemical to control the postharvest disease in garlic in only MRL aspect.

• Food Science and Preservation
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• v.10 no.1
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• pp.47-53
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• 2003

This study was carried out to investigate the quality characteristics and its distribution of Fuji Apple produced in Korea. The appels were collected 1mm the major producing areas of the apples, Cheongsong, Yechun, Bongwha, Singju and Yesan. Quality characteristics of the apples produced in these areas for 3 years were measured in terms of redness, size, weight, uniformity, defects, sweetness, firmness, pH and total acidity, The average redness for 3 years in the apples was 88.94% and the apples in the third year had the highest value, 93.88%, in redness. The average size toy 3 years in the apples was 87.17mm and the average weight was 276.74g. In external appearance, defects on the surface of the apples caused by physical factors were more serious than those by insects. Sweetness was 14.81$^{\circ}$Brix and its variation was 1.78$^{\circ}$Brix. The average firmness for 3 years in the apples was 0.83kgf, The pH value and total acidity for 3 years in Fuji apples were 3.83 and 0.32 ％, respectively, and the values had no significant difference between production years. According to the producing areas, the apples of area A in redness showed the highest value, 91.10% and these of area D showed the lowest value, 86.15%. The highest value for size was 88.12mm for area C and the lowest value was 86.40mm for area D. The apples of area B had the heaviest weight, 280.49g and these of area D in weight had the lowest value, 273.89g. No great difference showed in external defects and total acidity of the apples among the areas. In sweetness by districts, the apples of area E had the highest value, 15.32$^{\circ}$Brix, while area B was for the lowest value, 14.58$^{\circ}$Brix. The firmness of Fuji apples produced in area D and E was the highest value, 0.83kgf, and the apples of area C were the lowest value, 0.76kgf far firmness.

• Food Science and Preservation
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• v.23 no.3
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• pp.438-444
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• 2016

This study was performed to determine the optimal freezing point for the reliable cold storage of Korean agricultural products, and to provide basic data for determining the storage temperature based on the quality characteristics. Additional supercooling temperature analysis was conducted to explore the possibility of supercooling storage. To determine the effects of quality characteristics on the freezing point, the hardness, acidity, moisture and sugar content were analyzed. The crops were frozen using customized cooling unit and their freezing and supercooling points were determined based on their heat release points. The freezing temperatures of garlic, leek, cucumber, hot pepper, grape, oriental melon, netted melon, peach, cherry tomato, plum, daikon, sweet persimmon, apple, sweet potato, mandarin, pear, and strawberry were -1.6, -0.5, -0.5, -0.7, -1.6, -1.6, -1.3, -0.8, -0.3, -1.1, -0.3, -1.7, -1.5, -1.5, -0.8, -1.5, and -$0.9^{\circ}C$, respectively; otherwise, supercooling points were -7.8, -3.7, -3.3, -4.9, -5.7, -4.6, -2.8, -3.3, -5.9, -4.2, -0.8, -4.7, -3.2, -3.7, -4.7, -4.2, and -$3.4^{\circ}C$, respectively. These results suggest that the ideal freezing temperature of crops could be estimated through freezing point depression because of their sugar content, and this technique should be used to maintain an optimum storage temperature. However, cold storage is complicated and further study is required because of the effects of long-term cold storage on the crops.

• Korean journal of applied entomology
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• v.10 no.2
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• pp.109-116
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• 1971

The study involved determination of resistance levels of spider mites to Metasystox, Folidol and C-8514 using slide dip technique: a feid trial of alternative acaricides using an O/P resistant strain. 1. Resistant strains of two-spotted spider mite( Tetranychus urticae Koch) were collected from Taegu, Kyungsan, Chunchun, Yesan, Suwon, Osan and Chungju, and kept in the glasshouse through the experiments. Resistant strains of European red mite (Panonychus ulmi Koch) were collected from Chungju, Taegu, Yesan, Chunchun, Suwon and Whasung, and Wonju susceptible was collected. Immediately after collection, tests were applied. All strains except susceptible populations had regularly been sprayed with Organo-phosphates including Parathion (or Folidol), Metasystox, Phenkapton and Trithion for more than the ten Bast years; and Organo-chlorines such as Kelthane and C-8514 more than five years. Comparisons of the resistant strains and susceptible strains at the $LC_50$ values are as follows: a. With Metasystox, resistance levels of the Chungju, Taegu, Yesan, Chunchun and Suwon resistant strains of P. ulmi were respectively, 96,52,4,3 and 2, times as resistant as the Wonju susceptible strain. b. With Folidol, resistance levels of the Chungju, Chunchun, Yesan, Whasung and Suwon strains of P. ulmi showed respectively, 126, 48, 33, 30 and 6-fold resistance levels over the susceptible strain. c. With C-8514, resistance levels of the Taegu, Suwon, Whasung and Chungju strains of P. ulmi were 42, 31, 30 and 20 times greater than the susceptible strain, respectively. d. With Metasystox, resistance levels of the Taegu, Chunchun, Yesan and Suwon, strains of T urticae were respectively, 32,29,25 and 17 times as resistant as the susceptible strain. e. With C-8514, resistance levels of the Taegu, Chungju and Kyungsan strains of T. urticae showed respectively, 59, 29 and 19-fold resistance levels over the Osan strain. 2. Field trials were carried out to assess the toxicities of eleven alternative materials which would be used for control of O/P resistant strain of Panonychus ulmi. The acaricide groups represented were 2 Organo-chlorines (Kelthane MF and Prethylen), 1 carbamate (Furadan), 1 nitrophenyl (Morocide), 1 carbonate (Morestan), 1 tin(Plictran), 1 fluorine (Nissol), 2 mixtures (Fundal and Banmite) and Organo-phosphate (Phenkapton). Of all acaricides tested Kelthane, Plictran, Fundal and Morestan were the most effective; fol]owed by Banmite, Furadan, Prethylen and Nissol. Sumite and Morocide were intermediate, but Phenkapton(Organo-phosphate) was very poor. In other words, a first application of the above outstanding materials gave very high degrees of control of O/P resistant population of European red mite for about 7 to 12 days. However, the results indicate that secondary application would sometimes be necessary. There was no foliage damage to apple trees by any of the acaricides tested of the concentrations used.

• Korean Journal of Organic Agriculture
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• v.22 no.1
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• pp.97-113
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• 2014

An actual proof experiment was carried out to establish the production of high quality organic rice at farm household in Gwangjin, Junnam, Korea 2011. Experimental plot was designed with conventional organic cultivation and manual organic cultivation in both Hopeongbyeo and Onnuri varities. Experimental field was consisted with suitable drainage loam soil, anryong series, and normal paddy field. Chemical characteristics of the soil were investigated from initial soil and soil after harvest in experimental sites. Seed disinfection was treated with hot water dipping method at $60^{\circ}C$ for 10 min. Rice transplanting was carried out at 17 June with 25 days seedling using machine transplanting. Golden apple snail was used to prevent weed growth as middle size (1.5~1.7 kg/10a) at one week after rice transplanting. Amount of applied fertilizer in experimental plot was supplied with organic fertilizer for the shortage after harvest of hairy vetch (1,100 kg/10a). Bordeaux mixture was used to control of sheath blight and neck blast disease in all experimental plot at 19 Aug. Application of chitin culture solution was treated in manual organic cultivation at 2 and 15 Aug. At late growth stage, incidence rate of neck blast was the highest level at Hopyeongbyeo in conventional organic cultivation. Incidence rate of sheath blight in both Hopyeongbyeo and Onnuri was higher in conventional organic cultivation than in manual organic cultivation. Incidence of rice leaf folder was the highest level at Onnuri in conventional organic cultivation. Yield index in manual organic cultivation was increased by 13% and 38% at Onnuri and Hopyeongbyeo, respectively, compared with conventional organic cultivation. Head rice percentage in both Hopyeongbyeo and Onnuri was slightly increased in manual organic cultivation. These results indicate that high quality production of rice organic cultivation could be depending on management of safe fertilization with nutrient content in soil.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.632-637
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• 1996

Effects of refrigeration temperature and its fluctuation range on the growth of psychrotrophic microorganisms and the quality of refrigerated foods such as apple, fish and oyster were evaluated to find optimum storage conditions for a domestic refrigerator. Refrigeration temperature was $2^{\circ}C$ or $4^{\circ}C$, and fluctuation ranges were varied: ${\pm}0.3,\;{\pm}1.0,\;{\pm}1.2,\;or\;{\pm}4.0^{\circ}C$. Changes in hardness of apples stored at $2{\pm}0.3^{\circ}C$ were much slower than those of apples stored at $4{\pm}1.2^{\circ}C$. Freshness of fish and oyster also lasted much longer at low temperature such as $2{\pm}0.3^{\circ}C$. The growth of Listeria monocytogenes inoculated on sliced ham was inhibited for 1 month at $2{\pm}0.3^{\circ}C$, but the cells at $4{\pm}1.2^{\circ}C$ began to grows as time elapsed. Therefore, it was expected that shelf-life of certain food stored in a domestic refrigerator could be extended by lowering temperature to $2^{\circ}C$ and by reducing fluctuation range of refrigerator.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1275-1282
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• 1999

The quality changes by storage conditions were examined in order to establish the optimum CA storage conditions of unbagged and bagged 'Fuji' apples. The weight retention rate of apples was higher in CA than air storage, but there was no significant difference among CA conditions. Bagged apples had higher weight than unbagged apples under the same condition. The loss of flesh firmness, titratable acidity and green color of apples was retarded more effectively in 1% $O_2$ than 3% $O_2$ storage, and in $0^{\circ}C$ and 3% $CO_2$ than $2^{\circ}C$ and 1% $CO_2$ with 1% $O_2$ Titratable acidity tended to decrease more rapidly in bagged than unbagged apples. Soluble solid was not affected by storage conditions. Internal browning was developed within 2 months in 1% $O_2$ and 3% $CO_2$ storage, but there was no significant difference according to storage years and bagging treatment. At the sensory evaluation, unbagged apples were rated as higher quality than bagged apples after 8 months storage, and the hardness, juiciness, acidity and overall acceptability of apples stored in 1% $O_2$ were Higher than those in 3% $O_2$ but those of apples stored in 1% $O_2$ were not affected by $CO_2$(1, 3%) and temperature(0,\;$2^{\circ}C)$ differences. Above results suggest that the optimum CA storage condition of 'Fuji' apples is $0^{\circ}C,\;1%\;O_{2}+1%\;CO_2$.

• Korean Journal of Plant Resources
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• v.29 no.5
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• pp.598-603
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• 2016

The aim of this study was to elucidate the influence of vigor of a bearing shoot in ‘Bluecrop’ Highbush Blueberry (Vaccinium corymbosum L.) on growth characteristics of shoots and fruits. Bearing shoots were classified with BS (bearing shoot) and BMB (bearing mother branch). The vigor of bearing shoots were divided into four arbitrary categories; A was thin (< 6.0 ㎜) BMB and short (< 10 ㎝) BS, B was thin BMB and long (≥ 10 ㎝) BS, C was thick (≥ 6 ㎜) BMB and short BS and D was thick BMB and long BS. Shoots from D were longer (6.5 ㎝) and thicker (1.70 ㎜) than those from the others. Shoots of D had more leaves (5.8 ea) than those of the others. Leaf area of D was larger (13.5 ㎠) than those of the others. The first harvest of D was one week faster than the others. Ratio of big berry (>14 ㎜) from the long BSs was higher (B : 41.7, D : 46.8%) than that from the short BSs. Soluble solid content of small berrys did not show any different according to vigor of bearing shoots, but soluble solid content of big berrys of the long BSs was higher (B : 16.2, D : 15.6°Bx) than those of the short BSs. The thickness of BMB did not affect ratio of fruit size and soluble soild content. The long BSs would be proper than the short BSs for bearing bigger fruits.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.148-155
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• 2013

Sulfoxaflor is a new active ingredient within the sulfoximine insecticide class that acts via a unique interaction with the nicotinic receptor. The MRLs (maximun residue limit) of sulfoxaflor in apple and pear are set at 0.4 mg/kg and that in pepper is set at 0.5 mg/kg. The purpose of this study was to develop an analytical method for the determination of sulfoxaflor residues in agricultural commodities using HPLC-UVD and LC-MS. The analysis of sulfoxaflor was performed by reverse phase-HPLC using an UV detector. Acetone and methanol were used for the extraction and aminopropyl ($NH_2$) cartridge was used for the clean-up in the samples. Recovery experiments were conducted on 7 representative agricultural products to validate the analytical method. The recoveries of the proposed method ranged from 82.8% to 108.2% and relative standard deviations were less than 10%. Finally, LC-MS with selected ion monitoring was also applied to confirm the suspected residues of sulfoxaflor in agricultural commodities.

• Journal of Plant Biotechnology
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• v.40 no.4
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• pp.210-216
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• 2013

Efficient regeneration methods and transformation system are a priority for successful application of genetic engineering to vegetative propagated plants such as grape (Vitis labrusca L.). This research is to establish shoot regeneration system from plant explants for 'Campbell Early', 'Tamnara', 'Heukgoosul', 'Heukbosek' using two types of plant growth regulators supplemented to medium. The highest adventitious shoot regeneration rate of 5% was achieved on a medium containing of Murashige and Skoog (MS) inorganic salts and Linsmaier and Skoog (LS) vitamins, 2 mg/L of TDZ and 0.1 mg/L of IBA. Leaf tissue of 'Campbell Early', was co-cultivated with Agrobacterium strains, LBA4404 containing the vector pBI121 carrying with CaMV 35S promoter, gus gene as reporter gene and resistance to kanamycin as selective agent, the other Agrobacterium strains, GV3101 containing the vector pB7 WG2D carrying with mPAP1-D gene. mPAP1-D is a regulatory genes of the anthocyanin biosynthetic pathway. 'Campbell Early' harboring mPAP1-D gene was readily able to be selected by red color due to anthocyanin accumulation in the transformed shoot. These results might be helpful for further studies to enhance the transformation efficiency in grape.