• Korean journal of applied entomology
• /
• v.42 no.3
• /
• pp.269-277
• /
• 2003

Some species of true bugs have become serious problems in rice, upland crops, and tree fruits. It would be meaningful to understand research status by reviewing articles on those true bugs in Korea. Articles on those bugs published in several scientific Korean journals were reviewed, except articles on true bugs on rice plants; CD Part 1 included classification and morphological studies on eggs and larvae of Piesma spp., on external genitalia of Gonopsis affinis, and on spermathecae of some Podopinae and Asopinae species. $\circled2$ Development and growth analysis of Piesma sp., P. maculata, and 2 species of Coreidae were reviewed in part 2. $\circled3$ In part 3 we reviewed with major pest bug species on soybean, sweet persimmon, yuzu, citrus, chrysanthemum, and Cynanchum wilfordii, and insect fauna in mountain areas. $\circled4$ In part 4, damage levels in soybean, sweet persimmon, yuzu, grapes were reviewed. $\circled5$ ID In part 5 we reviewed seasonal occurrence patterns of Halyomorpha halys, Plautia stali, Riptortus clavatus in sweet persimmon orchards, of some species in soybean fields, of Nysius plebejus on chrysanthemum, and of Tropidothorax cruciger on Cynanchum wilfordii. $\circled6$ Chemical control methods in a sweet persimmon orchard, in grapevine yards, in a soybean field, and in a chrythansemum field were introduced in part 6. Some laboratory bioassay on insecticides against R. clavatus were mentioned, too. $\circled7$ Finally in part 7, researches on transmission by Halyomorpha halys and Cyrtopeltis tenuis of micoplasma-like organism which is a pathogen of paulownia withces' -broom to Catharanthus roseus were reviewed.

• Journal of the East Asian Society of Dietary Life
• /
• v.26 no.3
• /
• pp.250-259
• /
• 2016

This study was carried out to investigate the effects of tangerine (Citrus unshiu) peel on the physicochemical properties and sensory score of pork patties. Four types of pork patties were evaluated: T0 without tangerine peel, T1 with 0.3% tangerine peel, T2 with 0.7% tangerine peel, and T3 with 1.0% tangerine peel. The pH level changed based on the storage period. The pH levels of T2 and T3 were lower than those of T0 and T1 during storage. The L-value (lightness) of samples did not significantly change, and showed no significant difference during storage. The a-value (redness) decreased during storage, and that of T0 was lowest among the samples. The b-values of samples did not significantly change, whereas that of pork patties with tangerine peel was higher than that of pork patty without tangerine peel. The TBARS increased with a longer storage period, and the values for T0, T1, T2 and T3 were 0.82, 0.32, 0.26 and 0.26 mg/kg, respectively, after 10 days of storage. DPPH radical scavenging activity decreased with a longer storage period, and those of T2 and T3 were significantly higher than those of T0 and T1. The VBN contents of T0 and T1 increased with a longer storage period, and that of T0 was highest among the samples. Water holding capacity decreased, and cooking loss increased, whereas those of samples did not significantly change during storage. Hardness and chewiness increased while springiness and cohesiveness decreased during storage. The results of this study show that tangerine peel is a natural antioxidant, due to its antioxidative activity and does not affect physical characteristics. Therefore, addition of 0.7% tangerine peel may be suitable for manufacture of patties.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.3
• /
• pp.222-229
• /
• 2009

This study was performed to evaluate effect of different fertilization management practices on soil microbial activities and community structure using soil enzyme activities and PLFA contents in volcanic ash citrus orchard soil. Six experiment plots have differently managed based on the recommended application rate(NPK) of chemical fertilizer and compost for 13 years. Experiment plots were composed of no-fertilization(control), compost only, half amount of NPK with compost (1/2NPK+COM), NPK, NPK with compost(NPK+COM), and 3 times amount of NPK(3NPK). Soil samples collected in early March, May, July, and September 2007. Urease activity was high at NPK+COM in March, May, and September. It was higher in NPK+COM than in NPK. Urease activity decreased according to the order NPK>compost>control in March and May; compost>NPK>control in July and September. Dehydrogenase activity was significantly higher in 1/2NPK+COM($4.3ug\;TPF\;g^{-1}\;24h^{-1}$) than in control($2.4ug\;TPF\;g^{-1}\;24h^{-1}$), May. $\beta$-glucosidase activity was significantly higher in NPK and 1/2NPK+COM than in control, May. In March, Total PLFA contents were higher in NPK+COM($349.2n\;mol\;g^{-1}$) than in 3NPK($228.5n\;mol\;g^{-1}$). And that were higher in 1/2NPK+COM($237.8n\;mol\;g^{-1}$) than in 3NPK($133.1n\;mol\;g^{-1}$), May. Distribution ratio of soil microbial groups by PLFA biomaker were not significantly difference in between seasonal and treatments. Principal component analysis by PLFA profiles showed that microbial community in compost and 3NPK plot were different compared with other treatments in March. But Differences in compost and 3NPK plot were not found in May. Our result showed that the change of microbial community structure affected by fertilization effect and seasonable variation.

• Applied Biological Chemistry
• /
• v.17 no.3
• /
• pp.219-234
• /
• 1974

A series of experiments was conducted to study the behavior of the phosphorus added to the soils having the high phorphorus fixing capacity derived from volcanic ash in Cheju Island. Soil samples were taken from different depths of 0-10, 10-30, and 30-50cm in six citrus orchards where heavy application of phosphate fertilizer has been practised. Various forms of phosphorus were determined and phosphorus adsorption experiments were performed. The results obtained can be summarized as follows: 1. The content of inorganic phosphorus fractions determined by the method of Chang and Jackson was: water soluble P

• Journal of Korean Society of Rural Planning
• /
• v.14 no.1
• /
• pp.43-50
• /
• 2008

The dichotomous-choice contingent valuation method is applied to estimate the landscape value of Jeju mandarin(orchard). A distribution-free approach, Turnbull empirical distribution model, is employed to solve negative willingness to pay and truncation problems. The data used are collected from the interviews with tourist about willingness-to-pay at the various donation amount levels of Jeju mandarin(orchard)'s landscape value. The evaluation result is shown that the average amount of willingness to pay for the Jeju mandarin's landscape value is 12,926 won per person with standard deviation of 1,874.7 won/person. When the number of Jeju visitors is considered, the economic value of Jeju mandarin's landscape rises every year(2005:64.89 billion won, 2011: 84.43 billion won). The average economic value of Jeju mandarin's landscape are estimated 59.65 billion won during 2000-2005 and 76.88 billion won during 2006-2011, respectively.

• Korean journal of applied entomology
• /
• v.16 no.4 s.33
• /
• pp.245-247
• /
• 1977

Penicillium digitatum SACCARD, P. italicum WEHMER, Botrytis cinerae PERSOON and Sclerotinia sclerotiorum MASSE. were the main storage diseases on the cold injured mandarin at Jeju in 1975. The losses observed through the materials used were $18.3\%$ which consists of $8.1\%$ by diseases and $10.2\%$ by water rot as the result of cold and snow damages at harvest stage in Jeju. The total amount of damages estimated at shipping stage were 915M/T in value of 135 million Won from the rot waste of 675M/T by the end of 1975. Since cold injury is known as the main factor of the fruit rot, shipping and storage process as well as disease control measures are discussed.

• Journal of Food Hygiene and Safety
• /
• v.34 no.1
• /
• pp.13-21
• /
• 2019

A method was developed for the simultaneous detection of an antibiotic fungicide, streptomycin, and its metabolite (dihydrostreptomycin) in agricultural products using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were extracted using methanol adjusted to pH 3 using formic acid, and purified with a HLB (Hydrophilic lipophilic balance) cartridge. The matrix-matched calibration curves were constructed using seven concentration levels, from 0.001 to 0.1 mg/kg, and linearity of five agricultural products (hulled rice, potato, soybean, mandarin, green pepper), with coefficients of determination $(R^2){\geq}0.9906$, for streptomycin and dihydrostreptomycin. The mean recoveries at three fortification levels (LOQ, $LOQ{\times}10$, $LOQ{\times}50$, n = 5) were from 72.0~116.5% and from 72.1~116.0%, and relative standard deviations were less than 12.3% and 12.5%, respectively. The limits of quantification (LOQ) were 0.01 mg/kg, which are satisfactory for quantification levels corresponding with the Positive List System. All optimized results satisfied the criteria ranges requested in the Codex guidelines and the Food Safety Evaluation Department guidelines. The present study could serve as a reference for the establishment of maximum residue limits and be used as basic data for detection of streptomycin and dihydrostreptomycin in food.

• Korean journal of applied entomology
• /
• v.14 no.3 s.24
• /
• pp.141-146
• /
• 1975

Experiments were carried out to know the effects of emulsifiable DBCP, (Dibromo Chloropropane) for control of the citrus-root nematode, Tylenchulus semipenetrans in Orchards of chinese citron and mandarine orange for four years of 1967-1970. Nematode population density decreased as the amount of DBCP increased. In mandarine orange orchard, the nematode population density decreased after second treatment mainly because of bad drainage of the soil, while in Chinese citron orchard, it fell off sharply after just one treatment since the soil was well drained. Yields of Chinese citron increased as much as $26\%$ in 4.4l/10a injection, 1$18\%$ in 4.4l/10a drench; yields of mandarine orange increased as much as $11\%$ in 4.41/10a injection and $13\%$ in 4.4l/10a drench.

• Horticultural Science & Technology
• /
• v.30 no.1
• /
• pp.85-89
• /
• 2012

To investigate the bird's dieting behavior for several fruits in orchards, this study was carried out in 2008. Black-billed magpies (Pica pica), azure-winged magpies (Cyanopica cyanus), and brown-eared bulbuls (Hypsipetes amaurotis) made their unique marks on the surface of pear and apple fruits; black-billed magpies pecked fruits strongly and left round holes with perpendicular angle, whereas those of azure-winged magpies and brown-eared bulbuls were sack-shaped with narrow neck and marked unique stripes on the skin. For the fruits of pear and apple from bagging practices, the birds showed different foraging behavior; black-billed magpies could injure all kinds of fruits whether with paper bags or not, but azure-winged magpies and brown-eared bulbuls could not attack the fruits with paper bag. Azure-winged magpies and brown-eared bulbuls preferred pear fruits to those of apples and satsuma mandarins in the cage trials. To reduce the injuries by azure-winged magpies and brown-eared bulbuls on pear and apple fruit, wrapping bag should not be impaired. Introducing azure-winged magpies to Cheju should be prohibited for the potential citrus injury by them.

• The Korean Journal of Pesticide Science
• /
• v.5 no.4
• /
• pp.40-44
• /
• 2001

Pesticide actual usage in fruit crop cultivation was surveyed, and usage trends of individual pesticides were evaluated to provide data for the development of indicators of environmental impact. The amount of pesticide used for fruit crops indicated the order of fungicide>insecticide>herbicide unlike the case of paddy rice. The fungicide rate of total usage was 72% in apple cultivation. Top ranking fungicides used on fruits were Mancozeb, Propineb, Thiophanate-methyl and the main insecticides were Mancozeb, Propineb, Thiophanate-methyl. The usuage by formulation types showed the order of WP>EC>SL>SC>SP>WG. Pesticide usage (a.i.) per hectare by different fruits was citrus 48.6kg, apple 27.1kg, pear 18.6kg, persimmon 17.5kg, peach 11.3kg and grape 9.2kg. Comparison of pesticide usage (a.i.,kg/ha) in some fruit crops between Korea and USA indicated that more pesticides were used for citrus, pear and peach in USA than Korea while more pesticides were used in Korea than USA for apple.