• Korean journal of applied entomology
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• v.48 no.2
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• pp.245-251
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• 2009

Without pesticide applications, mass-trapping by sex pheromone was successful to control Spodoptera litura (Fabricius) in a large scale tomato glasshouse (10,000 $m^2$) at a low cost of 60 won/$m^2$. Pheromone traps were placed both inside and outside of the glasshouse. Inside the glasshouse traps were installed in a regular space, one trap per 500 $m^2$, to catch the moths that were present in the glasshouse, and traps were also set outside of the glasshouse, at intervals of ca. 20 m, to prevent the moths from invading the glasshouse. In the experiment, more than 400 S. litura were captured per trap.

• Korean journal of applied entomology
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• v.50 no.3
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• pp.215-220
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• 2011

This study aimed to estimate control thresholds for managing common cutworm, Spodoptera litura Faricius (Lepidoptera: Noctuidae) at different larval densities and growth stages of Chinese cabbage in field conditions. The percent yield reduction (Y) of Chinese cabbage infested by different densities of S. litura (X, no. of larvae/100 plants) for three weeks were estimated by Y=-21.85X+1300 (R2=0.997) 5 days after transplanting and Y=-12.1X+1382 (R2=0.998) 20 days after transplanting. Based on the relationships between the densities of S. litura larvae and the yield index of chinese cabbage, the number of larvae (2nd to 3rd instar) which caused 5% loss of yield was estimated as 2.9/100 plants 5 days after transplanting, and 5.6/100 plants 20 days after transplanting.

• Food Science of Animal Resources
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• v.26 no.2
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• pp.183-188
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• 2006

This study was carried out to investigate the carcass grade and characteristics of pigs by carcass weight and backfat thickness. Data used in this experiment were collected and analyzed from a total of 656 pigs composed of 128 gilts and 528 barrows at commercial public slaughter house. The carcass grade of gilts was superior to that of barrow. The carcass weight by gender tended to be heavier in castrated pig than in gilt. Backfat was significantly (p<0.05) thicker in castrated pig than in gilt. Differences between castrated pig and gilt on meat colour, marbling standard, water holding capacity, and marketing age were not significantly found. However, the level of carcass grade was higher ratio in gilt group than in castration. The appearance of percentage of PSE (pale, soft, exudative) of gilt group was superior to that of castrated group. There were significant differences among carcass weight in the marbling score (p<0.05) and water holding capacity (p<0.05). There was significant difference among backfnt thickness in carcass weight (p<0.05), marbling score (p<0.05) and water holding capacity (p<0.05).

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.27-35
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• 2007

Seasonal occurrences of tobacco cutworm, Spodoptera litura and beet armyworm, Spodoptera exigua were observed using sex pheromone traps at different locations and climatic regions in Yeongnam district. In Gyeongnam province, S. litura male adults kept occur from mid or late March to mid or late November Whereas in Gyeongbuk province, S. litura occurred from mid or late April to early or mid November with exception at Uljin where it was late May to late October. According to the climatic regions, the peak occurrence of S. litura was middle September at the southern coast region, late August at the inland and the basin region, middle August at the inland mountainous region, and early September at the eastern middle coast region. The occurrence rate of S. litura was the highest at Jinju with 20.0% and the lowest at Changyeong with 8.6% in Cyeongnam province, while it was the highest at Sungju with 3.3% and the lowest at Uljin with 0.8% in Gyeongbuk province. In accordance with the climatic regions, the occurrence rate of S. litura was the highest at the inland region with 43.7%, and followed by the southern coast region (36.3%), the basin region (8.4%) and the inland mountainous region (7.0%), and was the lowest at the eastern middle coast legion with 4.6%. On the other hand, S. exigua occurred from early March to middle November with the exception of the eastern middle coast region including Pohang, Yeongdeog and U]ien in Cyeongbuk province where it occurred from mfd April to middle November. The peak occurrence of s. exigua was early August at the inland region, the basin region and the inland mountainous region, and was late of August at the southern coast region and the eastern middle coast region. The occurrence of S. exigua was the highest at Changyeong with 1.6% and the lowest at Busan with 0.4% in Gyeongnam province, while it was the highest at Sungju with 37.2% and the lowest at Uljin with 2.7% in Gyeongbuk province. The climatic regional occurrence rate of S. exigua was the highest at the basin region with 54.3%, and followed by the inland mountainous region (29.9%), the eastern middle coast region (9.3%) and the inland (3.9%), and was the lowest at the southern coast region with 2.6%. As a whole, S. litura occurred more in Gyeongnam province than Cyeongbuk province, while S. exigua occurred more in Gyeongbuk province than Gyeongnam province. According to the regions grouped by climatic differences, the occurrence of S. litura and S. exigua was the highest at the inland region in Gyeongnam province and at the basin region in Gyeongbuk province. The total number of S. litura captured by sex pheromone trap was 2.4 times higher than that of S. exigua. However, the first occurring time and the peak occurrence of S. exigua were slightly earlier than those of S. litura.

• Food Science of Animal Resources
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• v.31 no.2
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• pp.257-265
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• 2011

The current study was conducted to compare the growth performance and physico-chemical characteristics of Hanwoo bulls and steers of different slaughtering ages. Thirty-six Hanwoo (average age, 13-mon) were allocated into either a bull or steer group (18 animals/group). Each group was sub-divided into 26-, 28-, and 30-mon-old age groups (six animals/group). Surgical castration was performed in the steer group immediately after the experimental groups were assigned. Growth performance of the animals, as well as carcass characteristics and fatty acid composition of M. longissimus dorsi were determined. Cold carcass weights increased as carcass slaughtering age increased in both Hanwoo bulls and steers (p<0.05). Backfat thickness was thickest (p<0.05) in 28-mon-old Hanwoo bulls and 30-mon-old steer, and the M. longissimus dorsi area was widest (p< 0.05) in 28-mon-old Hanwoo bulls and steers. Marbling score, cooking loss, and water holding capacity (WHC) were higher (p<0.05) in 30-mon-old Hanwoo bulls and steers as slaughtering age increased. The shear force value was highest in 30-mon-old Hanwoo bulls and 26-mon-old Hanwoo steers compared to that in other groups. The unsaturated fatty acid composition in M. longissimus dorsi was significantly (p<0.05) higher in 28- and 30-mon-old Hanwoo bulls and steers than that in other groups. The results suggest that castration, even at late stages of Hanwoo development, improved beef carcass quality grade, and that no difference in beef quality grade had occurred (marbling score and WHC) in 28- and 30-mon-old slaughtering age Hanwoo steers.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.119-124
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• 2013

This study was conducted to investigate meat quality and sensory characteristics between castrated and non-castrated dairy goats. Dairy goat of Saanen breeds was slaughtered at an age of 6 mon. Then, characteristics of dairy goat meat were analyzed to chemical compositions, collagen content, pH, meat color, cooking loss, water-holding capacity, shear force, protein solubility, and myofibrillar protein fractions by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Also, odor from dairy goat meats was analyzed by sensory evaluation and volatile substances by gas chromatography-mass spectrometry (GC-MS). As a result, the chemical compositions and physicochemical characteristics were not significantly different between castrated and non-castrated dairy goats meat. Also, there is no difference protein solubility (sarcoplasmic, myofibrillar and total protein) and protein fraction by SDS-PAGE. Sensory evaluation results in odour scores are highly (p<0.05) non-castration dairy goat meat better than castration. As a result, overall palatability was higher (p<0.05) in castrated goat meat when compared with non-castrated one. The indole and octadecanoic acid by GC-MS based on sensory evaluation results were only detected in non-castrated dairy goat meat. Therefore, distribution for goat meats castrated compared to non-castrated dairy goat meat is expected to be able to get a good response to the Korean consumer.

• Korean journal of applied entomology
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• v.60 no.2
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• pp.221-228
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• 2021

The fall armyworm (FAW), Spodoptera frugiperda (Smith), is a notorious invasive migratory pest native to the tropics that has recently invaded South Korea with subsequent damage to cornfields. This study was conducted to evaluate the damage patterns on corn plants caused by the migratory and subsequent generations of FAW. The early migrant generation-related infestation rates reached an average of 13.2%, ranging from a minimum of 4.3% ('Allog-i') to a maximum of 33.0% ('Chodang'), depending on the corn cultivar. The proportion of FAW larvae-infested corn plants, in which the FAW survived until the pupal stage was 19.3%. The subsequent FAW generation caused considerable damage to the ears, resulting in 60% of ears with damaged kernels. This damage was markedly different from the nearly negligible damage caused by the migratory generation. The FAW larval dispersion was the most dynamic during the second instar stage and occurred along the same cornrow in line. In addition, we discuss the development of corn pant damage patterns caused by FAW. In summary, the results of the present study would provide useful basic information for the damage analysis of this pest for future studies.

• Korean journal of applied entomology
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• v.33 no.4
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• pp.225-229
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• 1994

The methanol extracts from 30 species of oriental medicinal plants belonging to 24 families were tested for their lhicidal and antifeeding activit~es against diamondback moth (Plutello xylostella L) and tobacco cutworn (Spodoptera litura F.) by a leaf-dipping method at a concentration of 5, 000 ppm. The methanol extract from Copti chinensis only showed a potent larvicidal activity against P xylostello. Strong antifeeding activity against P. xylostello was observed from the extmds from Platycodon grandiflorurn, Codonopsis pilosula, Asomm sieboldii, Rhus chinensis and Uthospermum erythrorhizon And a potent antifeeding activity against S. liturn was obtained from Akebia quinata and Equlsetum hyemale extracts. A significant antifeeding activity against both species was obtained from R chinensis and C. chinensis extracts.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.249-253
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• 1996

In the laboratory study, the toxicities of chlorpyrifos-methyl, chlorpyrifos, etofenprox, etofenprox+PAF' and deltamethrin for different larval instars of S. litura decreased significantly as larvae aged. LCso values for chlorpyrifos- methyl and chlorpyrifos increased significantly from 3rd instar larvae, while those for etofenprox+PAP and deltamethrin-increased from 2nd instar larvae. In pot study, no significant differences in control efficacy were observed among each treated plots and over 90% control efficacy at 5 d after treatment was obtained in all of the treated plots, except treatment with deltamethrin. Therefore four insecticides excluding deltamethrin will be effective for controlling S. litura. However, it will be probably important to select appropriate insecticides and decide a proper time of treatment because the developmental stage is a significant factor in deciding insecticide efficacy because various developmental stages of the tobacco cutworm inhibit in fields.

• Korean journal of applied entomology
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• v.27 no.4
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• pp.219-224
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• 1988

Rearing of Spodoptera litura fed on arfificial diet basically formulated with kindby bean powder was much promisible for production of S. litura nuclear polyhedrosis virus(SINPV) than that on kidney bean leaves. The $LC_{50}$ of SINPV against 3rd and 5th instar were $4.48{\times}10^{3}$ PIB/ml and $4.52{\times}10^{4}$ PIB/ml, respectively. The $LC_{50}${/TEX} of SINPV varied from 5.8 days to 7.7 days at higher inocula in the testes. The larval growth of 1st and 3rd instar larvae fed on virus were much delayed and the larval were killed within 4th instar in the former and within 5th instar in latter. S. litura larvae were very susceptible to multinucleocapsid nuclear polyhedsosis virus (MNPV) of Autographa californica, S. littoralis and Trichoplusia ni.