• Korean journal of applied entomology
• /
• v.16 no.2 s.31
• /
• pp.127-131
• /
• 1977

This experiment was conducted to evaluate the insect-proof netting, chemical sprays, application of attractants, fruit bagging and light trapping as the control methods of the fruit piercing moths in the orchards on reclaimed land in Sugyeri, Goksung, Chonnam Province, during June to October in 1976. The results are summarized as follows; 1. Insect-proof. netting effectively decreased fruit damage, compared as to the control, down to $9.4\%$ from $38.3\%$ in plum, $2.5\%$ from $53.0\%$ in peaches and $10.0\%$ from $29.0\%$ in grapes. 2. The control effects of chemicals varied significantly among the 7 insecticides tested: Deoclean, Naphthalene, and Thiometon were more effective to the fruit damages as low as $2.0\%,\; 3.6\%,\;and\;5.9\%$ respectively. while the fruit damage was rather high, $9.8\%$ for Demeton, $10.1\%$, for Takju +lead arsenate and $14.2\%$ for Padan. ,3. In the test with 7 attractants, the largest number of moths attracted and killed was 416.by Takju+brown sugar and the next was 307 by Takju+venegor while this number was 141 by mixed solution (see text) which is rather lower than expectation The fruit damage was lowest in Takju+honey and$5.2\%$, the next was $5.60\%$ for Takju+venegor and the highest was $12.0\%$, Takju alone. 4. Fruit bagging with polyethylene film effectively decreased the fruit damage from the inserts but brought about severe fruit rot and delay ripening. Meanwhile, paper bagging was less effective in preventing insects, resulting in $17.5\%$ fruit damage, however, gave no adverse effect other than slight Belay in ripening. 5. Light trapping was hardly expected to be a method of controlling these fruit piercing moths. However, the number of collected moths swarmed by electric light was 10.8 for can-descence, 0.95 for blue, and 0.22 for yellow light.

• Korean journal of applied entomology
• /
• v.53 no.2
• /
• pp.193-197
• /
• 2014

Transgenic crops that produce insecticidal toxins have a great potential for controlling target pest insects, but there is a growing concern about unintended influences on non-target species. In the present study, the preferences and performance of non-target green peach aphid, Myzus persicae (Sulzer), on transgenic cabbages (Brassica oleracea) that produce Bt toxin (Cry1Ac1) and untransformed control plants were investigated as a part of risk assessment. In a free-choice situation, the number of nymphs larviposited by 10 winged adults over 3 days was $21.9{\pm}1.8$ and $22.5{\pm}2.2$ on transgenic and the control plants, respectively, indicating that the aphids did not discriminate between the two types of plants. In a performance assay, the development time (D) and intrinsic rate of increase (rm) of wingless aphids reared on transgenic and control plants were also similar (D, $5.8{\pm}0.2$ and $5.9{\pm}0.1$ (days) and rm, $0.7{\pm}0.1$ and $0.8{\pm}0.1$, for transgenic and control plants, respectively). These results suggest that M. persicae is not significantly affected by transgenic Bt cabbage.

• Korean journal of applied entomology
• /
• v.53 no.2
• /
• pp.157-169
• /
• 2014

Between 2010 and 2012, diseases and insect pests of sweet persimmon were surveyed at sweet persimmon export complexes and non-export orchards in Suncheon, Jeonnam Province; Jinju, Changwon (Dongeup and Bukmyeon), and Gimhae, Gyeongnam Province; and Ulzu, Ulsan. The following diseases were found in the sweet persimmon orchards: angular leaf spot (Cercospora kaki), anthracnose (Colletotrichum gloeosporioides and Colletotrichum acutatum), circular leaf spot (Mycosphaerella nawae), powdery mildew (Phyllactinia kakicola), and gray mold (Botrytis cinerea). Circular leaf spot was the most frequent and serious disease, and C. gloeosporioides and C. acutatum were found on fruits. Thirty-three insect pest species that belonged to 32 genera of 20 families in 5 orders were found in the sweet persimmon orchards; the two-spotted spider mite, Tetranychus urticae, was also found in the surveyed orchards. Apolygus spinolae, Pseudaulacaspis cockerelli, and Adoxophyes orana were widely found in the surveyed orchards; Spodoptera litura and Homona magnanima were also recorded. Damage by insect pests was low, and the quarantine insect pests peach pyralid moth (Dichocrocis punctiferalis) and persimmon fruit moth (Stathmopoda masinissa) were rarely or not found in the sweet persimmon export complexes. In addition, other quarantine insect pests, such as persimmon false spider mite (Tenuipalpus zhizhilashviliae) and Japanese mealybug (Planococcus kraunhiae), were not detected. These quarantine insect pests were also not found in the sorting places, storage houses, and fruits for export; however, scale insects and two-spotted spider mites were found at a low rate. Although anthracnose (C. acutatum) infested fruit was found in the storage houses, only one in Jinju and Gimhae.

• Journal of Bio-Environment Control
• /
• v.23 no.4
• /
• pp.293-302
• /
• 2014

This study was carried out to develop rain shelter which can make an appropriate size and environment for Chinese cabbage rainproof cultivation. Fifty three farms with chinese cabbage rainproof cultivation system have been investigated to set up width and height of rain shelter. Mostly the width of 6m was desired for rain shelter and the height of 1.6m for their eaves, so these values were chosen as the dimensions for rain shelter. After an analysis of their structural safety and installation costs by the specifications of the rafter pipe, Ø$25.4{\times}1.5t$ and 90cm have been set as the size of rafter that such size costs the least. This size is stable with $27m{\cdot}s^{-1}$ of wind velocity and 17cm of snow depth. Therefore it is difficult to apply this dimension to area with higher climate load. In order to sort out such problem, the rain shelter has been designed to avoid damage on frame by opening plastic film to the ridge. Once greenhouse band is loosen by turning the manual switch at the both sides of rain shelter and open button of controller is pushed then switch motor rises up along the guide pipe and plastic film is opened to the ridge. Chinese cabbage can be damaged by insects if rain shelter is opened completely as revealed a field. To prevent this, farmers can install an insect-proof net. Further, the greenhouse can be damaged by typhoon while growing Chinese cabbage therefore the effect of an insect-proof net on structural safety has been analyzed. And then structural safety has been analyzed through using flow-structure interaction method at the wind condition of $40m{\cdot}s^{-1}$. And it assumed that wind applied perpendicular to side of the rain shelter which was covered by insect-proof net. The results indicated that plastic film was directly affected by wind therefore high pressure occurred on the surface. But wind load on insect-proof net was smaller than on plastic film and pressure distribution was also uniform. The results of structural analysis by applying pressure data extracted from flow analysis indicated that the maximum stress occurred at the end of pipe which is the ground part and the value has been 54.6MPa. The allowable stress of pipe in the standard of structural safety must be 215 MPa or more therefore structural safety of this rain shelter is satisfied.

• Korean Journal of Food Science and Technology
• /
• v.52 no.4
• /
• pp.317-324
• /
• 2020

In order to create the national food nutrient database, a total of 41 animal foods (ham, seafood, edible insects and eggs) were analyzed for their vitamin B₁₂ content and the applied immunoaffinity-HPLC was verified. Ham vitamin B₁₂ contents were 0.30-0.65 ㎍/100 g. Seafood showed relatively high vitamin B₁₂ level, where the values of fermented clam were the highest (26.80 ㎍/100 g) followed by fermented pollack roe. Vitamin B₁₂ was not detected in silkworm pupae and beetles, while relatively high levels were found in the two-spotted cricket imago (6.70 ㎍/100 g). Chicken and quail egg yolk had roughly 100- and 30-times higher vitamin B₁₂ levels as compared to their egg white. Vitamin B₁₂ contents in quail and chicken eggs were significantly enhanced by boiling (p<0.05). Results based on accuracy (97-102% recovery) and precision (<5% RSD) indicate that this study provides reliable vitamin B₁₂ information on animal foods consumed in Korea.

• Korean Journal of Environmental Agriculture
• /
• v.22 no.4
• /
• pp.246-250
• /
• 2003

In order to preserve the soundness of agro-ecosystem and products safety in agriculture, this study was evaluated environmental impact in relation to the INM (Integrated Nutrient Management) and IPM (Integrated Pest Management) at paddy fields at Ok-Chun and Yang-Pyung region. By introduction of INM with the application of BB(bulk-blanded) fertilizer based on soil analysis and IPM, the application rate of fertilizer was reduced to about $28.6{\sim}39.4%$ and the yield of brown rice was increased to about $3{\sim}10%$ compared to conventional practices. The concentrations of COD, $NH_4-N$, and $NO_3-N$ in irrigation water flowed to the environmental-friendly agriculture practices were 15.0, 0.67, and 1.39 mg/L, respectively. The concentrations of COD, $NH_4-N$, and $NO_3-N$ from paddy fields in drainage water were 12.4, 0.29, and 2.42 mg/L, respectively. The total number of the freshwater invertebrates was higher in field treated with fertilization by prescription with soil testing. Also, the population density of aquatic insects was higher than the other fields at both demonstration villages. In conclusion, it was possible to reduce the amount of fertilizer and agricultural chemicals application, and increase the yield of rice by application of the environmental-friendly agriculture practices.

• Journal of Korean Society for Atmospheric Environment
• /
• v.10 no.E
• /
• pp.371-386
• /
• 1994

Ecological examinations of the radial growth Patterns of pine trees(Pinus densiflora Sieb. et Zucc) growing on Mt. Namsan in central Seoul were made to test a Proposition that the pine trees decline due to the influence of air pollution and acid rain, which was proposed by some researchers in Korea, and the potential effects of current level of air pollutants to the growth of the Pine trees in central Seoul have been speculated. Tree-rings of 40 trees sampled at 3 sites of Mt. Namsan were prepared and examined using a Computer-aided Tree-Ring Measuring System at Kookmin University, Korea. Air Pollutant data collected by the Ministry of Environment( MOE ) and the Forestry Research Institute(FRI) were used to infer the general conditions of the environment. Correlation analysis was applied to the data set of tree growth and the other environmental factors. General information derived from the close examination of the tree-rings and the data on air pollution, drought and the other biological conditions suggested that the growth of the pine trees was severely affected by the occurrence of drought(climatic variation), the prevalence of the pine leaf gall midges(insects), and the suppression by the black locust trees(Robinia pseudo-acacia L.) (competition among trees). While the current condition of air pollution in Seoul cannot be categorized as good, the concentrations of air pollutants are not so high as to cause acute damages to the trees. In addition, while the data of rain acidity showed episodic low PHs of under 4.0, the average of them is far less acidic than those which were observed in either northeastern United States or central Europe, where the decline of trees were not solely attributed to any of the air pollutants. Considering the sequential facts that one of the most important environmental factors that affect the growth of trees is weather condition of the forest that the proposition of the decline of the pine trees was made without careful examination of the growth patterns and past growth history of them as well as the complex influences of many other factors including the weather conditions to the growth of trees, and that no objective explanation has been made on the causal relationships between the current condition of air pollution and the growth of the trees, such a proposition should be evaluated as invalid for the explanation of tree growth on Mt. Namsan in central Seoul, Korea. The author evaluates the factors of air pollution (including acid rain) as the predisposing factors, which may have the Potentials to chronically affect the tree growth at the forest ecosystem on Mt. Namsan for a long period of time. Ecosystem ecological studies should be further carried out to carefully explain both the functional and the structural aspects of the ecosystem processes, which include the biogeochemistry and the long-term changes of soil conditions as well as the growth of the other tree species on the mountain.

• Journal of Korean Society of Forest Science
• /
• v.83 no.3
• /
• pp.311-321
• /
• 1994

Experiments were conducted to evaluate the efficacy of ground and foliar sprinkling of natural water for control of the pine needle gall midge, Thecodiplosis japonensis, by disturbing the reproductive behavior of adults such as copulation and oviposition. Diurnal ground spray for whole area application and foliar spray for single tree treatment were tested at day time during the period of adult emergence. The results obtained are as follows : 1. The population density of overwintering larvae in soil was not affected by the water spray during the adult emergence period. 2. Spraying the water showed no effect on the whole period and number of adult emergence, but retarded early emergence and facilitated Late emergence. The difference in the emerging time by 50% emergence day was approximately 7 days. 3. Ground spray was significantly different from control in gall formation rates but was not sufficient for effective control. As a single-tree treatment, the foliar spray was found to be highly effective for control of the pine needle gall midge, Average gall formation of spray plots and untreated ones were 2.6% and 38%, respectively ; control value exceeded 90%. 4. Ground spray of water was not effective in reducing larvae in gall of needle. Foliar spray, however, reduced 45% of larval numbers. 5. Foliar spray accelerated shoot growth by 15%-18%. 6. Foliar spray was highly effective for the control of sucking insects, such as mites and aphids on pine trees.

• The Korean Journal of Pesticide Science
• /
• v.15 no.3
• /
• pp.254-268
• /
• 2011

Fenoxycarb, pyriproxyfen and methoprene are juvenile hormone mimic insecticide. These insecticides have been widely used for mosquito, fly, scale insects, and Lepidoptera. The purpose of this study was to develop a simultaneous determination procedure of fenoxycarb, pyriproxyfen and methoprene residues in crops using HPLC-UVD/MS. These insecticide residues were extracted with acetone from representative samples of four raw products which comprised brown rice, apple, green pepper, and Chinese cabbage. The extract was diluted with saline water, and then n-hexane/dichloromethane partition was followed to recover these insecticides from the aqueous phase. Florisil column chromatography was additionally employed for final clean up of the extract. The analytes were quantitated by HPLC-UVD/MS, using a $C_{18}$ column. The crops were fortified with each insecticide at 3 levels per crop. Mean recovery ratios were ranged from 80.0 to 104.3% in four representative agricultural commodities. The coefficients of variation were less than 4.8%. Quantitative limit of fenoxycarb, pyriproxyfen, and methoprene was 0.04 mg/kg in crop samples. A HPLC-UVD/MS with selected-ion monitoring was also provided to confirm the suspected residues. The proposed simultaneous analysis method was reproducible and sensitive enough to determine the residues of fenoxycarb, pyriproxyfen and methoprene in the agricultural commodities.

• Korean Journal of Organic Agriculture
• /
• v.18 no.1
• /
• pp.93-104
• /
• 2010

This study was conducted screening of the population densities of fungal pathogens and insect and observed the disease symptoms on the organic sweet corn seed producing field from 2008 to 2009. The dissemination spores, Alternaria sp., Cladosporium sp., Helminthosporium sp., Pyricularia sp., Collectotrichum sp., and Bipolaris sp., were detected and the three fungal spores from the front were observed for whole growth stage. Seed and seedling diseases were shown as the rotted seed and damping-off seedling caused by Penicillium sp. and Rhizoctonia sp.. The larva of Black cutworm cut down the root crown of seedlings. The damaged plants were ranged from 14% to 16%. On the Oriental corn borer, the population densities and the percentage of damaged plants were showed a low difference between two sweet corn varieties. The population densities of Oriental corn borer were scored as from 3.5 to 20.5 in 2008 and from 0.5 to 6 in 2009. Also the percentage of damaged plants were significantly increased until harvesting stage and was recorded from 7.5% to 21% in 2008 and from 1% to 46% in 2009. On the Corn leaf blight, the percentage of diseased plant were scored from 7% to 34% in 2008. The first occurrence of date was after June 18, and the percentage of diseased plant was continuously increased after August 21 and the values of diseased plants was ranged from 56% to 69% in 2009. On common smut, the percentage of diseased plant was recorded from 5% to 15% in 2008, and the first occurrence date were delayed as 17 days (July 17) and were showed less than 8% of diseased plants in 2009. Corn Southern Leaf spot was scored as average 11% at early stage and showed high score as 62% at September 19 in 2008. In 2009, the first occurrence date were advanced about 20 days (after June 8), and continuously increased up to 86% in 2009.