• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.3
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• pp.67-74
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• 1979

Peanut was cultured with varying planting density and sowing date with and without vinyl-film mulching. Vinyl-film mulching raised soil temperature 4.6$^{\circ}C$ higher than the non-mulched during April and early May, but later-on the soil temperature was similar between the two treatments. The ripening and slender grain ratio increased with closer spacing and earlier sowing. Compared with ordinary cultural practices of May 10th sowing without mulching the peanut yield increased by 9% by mulching sown May 10th, and by 49% by mulching and early sowing April 20th.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.421-428
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• 2008

With the comparison of native Orius strigicollis (Poppius) to European O. laevigatus (Fieber), we investigated biological characteristics such as developmental period, fecundity, life span, predation ability, and augmentation after release. Experiments were carried out at five temperature condition, $15^{\circ}C\;20^{\circ}C,\;25^{\circ}C\;30^{\circ}C$, and $35^{\circ}C$. In the case of O. strigicollis, egg period was $3.1{\sim}14.9$ days (hatchability: $46.7{\sim}88.2%$), and developmental period of nymphs was $9.4{\sim}42.8$ days (survival rate: $2.4{\sim}96.5%$). Fecundity at each temperature was 28.1, 107.9, 123.6, 127.3, and 18.1, respectively. Life span of adults was 63.4, 40.1, 22.1, 18.3, and 11.0 days, respectively. In the case of O. laevigatus, egg period was $3.1{\sim}13.5$ days (hatchability: $65.0{\sim}89.9%$), and developmental period of nymphs was $9.3{\sim}42.0$ (survival rate: $4.3{\sim}80.6%$) days. Fecundity at each temperature was 101.8, 218.6, 224.5, 219.5, and 15.7. Life span of adults was 70.6, 66.4, 32.6, 34.5, and 7.3 days, respectively. In long-day condition (16L:8D), fecundity of O. strigicollis and O. laevigatus was 105.8 $(18^{\circ}C){\sim}142.4(25^{\circ}C)$ and 109.5 $(18^{\circ}C){\sim}191.5(25^{\circ}C)$, respectively. In short-day condition (10L:14D), fecundity of them was 1.0 $(18^{\circ}C){\sim}31.8(25^{\circ}C)$ and 63.0 $(18^{\circ}C){\sim}198.8(25^{\circ}C)$, respectively. Daily prey consumption of second instar Frankliniella occidentalis was 14.3 and 10.9, respectively. In greenhouse, density of O. strigicollis begins to increase from mid May and peaked about early July (1.8 individual/flower), while that of O. laevigatus begins to increase from mid March and peaked about early June (6.6 individual/flower).

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.4
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• pp.350-356
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• 2016

The objective of this study was to evaluate the effect of different dietary corn levels in Total Mixed Rations (TMR) on growth and meat quality of castrated Korean black goats. For feeding trials, thirty-two castrated Korean black goats with similar age (average of 3 months) and body weight (average of 15.9 kg) were divided into the following four treatment groups: commercial feed (control), TMR containing 15% of corn (T1), TMR containing 25% of corn (T2), and TMR containing 35% of corn (T3) in a randomized complete block design. Final body weight was the highest in T2 (58.9 kg), followed by that in control group (53.1 kg). Average daily gain (ADG) and total dry matter intake (TDMI) were also the highest in T2 (100.2 g and 1,346 g, respectively). However, feed conversion ratio (13.4) was the lowest in T2. Carcass weight and dressing percentage in T2 and T3 were higher than those in the control. For meat quality characteristics, crude fat content was the highest in T2 (6.54%). Cooking loss (15.2%) was the lowest in the control. However, the control had the highest flavor value (5.3%). Oleic acid (C18:l) and palmitic acid (C16:0) were the highest in T2 (48.6% and 22.4%, respectively). Stearic acid (C18:0) was the highest in T1 (14.5%). Unsaturated fatty acid was the highest in the control (58.8%), followed by that in T3 (58.2%), T2 (57.8%), and T1 (54.4%). These results indicate that TMR containing 25% of corn could improve the growth performance and meat quality of castrated Korean black goats.

• Journal of Animal Science and Technology
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• v.55 no.1
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• pp.51-59
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• 2013

This study was conducted to investigate the dietary effect of total mixed rations (TMR) containing brewers grain, soybean curd and rice straw, respectively, on growth performance and carcass characteristics of Hanwoo steers. Twenty four Hanwoo steers (average body weight 168 kg) in 6 months age were randomly allocated to 4 experimental groups, which contained 6 animals per group during 22-months feeding trial. The treatment was composed of the group fed concentrate and rice straw separately (T1), the group fed TMR containing brewers grain (T2), the group fed TMR containing soybean curd (T3) and the group fed TMR containing rice straw (T4). Body weight (BW) was not different among treatment groups during the growing and middle fattening period. However, it was significantly greater in T4 group than in T2 group on the final BW (p<0.05). Average daily gain was significantly greater in TMR groups compared to T1 group on the growing and late fattening (p<0.05). However, it was not different in total average. Dry matter intake tended to be increased in TMR groups. The feed conversion ratio was significantly lower in T4 group compare to T2 group (p<0.05). According to the yield traits, carcass weight of T1, T2, T3 and T4 were 389.0, 368.4, 387.5 and 384.3 kg, respectively. The back fat thickness, rib-eye area, and yield index were not different among the groups. Meat color, fat color, texture and maturity were not significantly different among groups. However, marbling score and appearance rate of meat quality grade of over $1^+$ were greater in T2 and T3 groups compare to other groups. Therefore, these results indicated that TMR with brewers grain and soybean curd may be ameliorated the growth performance and carcass characteristics of Hanwoo steers.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.257-268
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• 1990

The regional characteristics in the occurrence of the rice stem borer, Chilo suppressalis (Walker), in Korea, were examined by analyzing the light trap data obtained from 39 locations during the years of 1965-1988, and some ecological significance of the overwintering larval populations collected from the four locations where some of the typical ecological-race have been known, the results obtained are as follows; The total number of the moths have decreased greatly throughout the nation since 1970. The decrease in the total number of moths related with those in the spring moth but not in the summer moths, and suggested that the changes in the rice production systems have effected significantly on the second generation of the insect. The variations between the regions had been gret in 1960's, decreasing phase in 1970's and increasing phase in loast decade. The overall average of 50% emergence dates have shifted earlier in both moths, and the changes were different considerably with the regions as wheel as in generations. When the overwintered larvae were incubated at $25^{\circ}C$ and RH of 90%, the average mortalities were 21.07% for Suweon, 43.06% for Iri, 63.51% for Jinju, 27.04% for Gwangju. When the overwintered larvae were incubated at $25^{\circ}C$ and RH of 90%, the average mortalities were different with the body weight; 45.44% for the larvae of less than 39 mg, 37.61% for 40-49 mg, 37.28% for 50-59 mg, 30.17% for greater than 60 mg. When the overwintered larvae wee incubated at $25^{\circ}C$, post-diapause larval development periods of body weight classes were 18.6$\pm$1.2 days for the larvae of less than 39 mg, 20.4$\pm$3.3 days for 40-49 mg, 21.4$\pm$3.2 days for 50-59 mg, 21.8$\pm$3.2 days for grater than 60 mg, and only the larvae of less than 39 mg, body weight class less than 39 mg was found statistically different in post-diapause larval development periods. From these results, the changes in the cultural practice of the rice have effected on the ecological pattern of the rice stem borer, and the effects seemed to be different with the generations, and with the regions where the different ecological races are distributing.

• Korean journal of applied entomology
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• v.38 no.1
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• pp.23-28
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• 1999

This study was conducted to determine the effect of temperatures, 24"C, 28$^{\circ}$C and 32"C,and food sources on pupal development, adult longevity and oviposition of tobacco cutworm, Spodopteralitura Fabricius. Percent pupation of S. litura was became higher at higher temperature from 23% to 88%.And its percent pupation was highest on soybean leaf (SL), followed by perilla leaf (PL), sweet potato leaf(SPL) and artificial diet (AD). Pupal weight ranged from 0.28g on SPL to 0.40 g on PL and was tended toheavier with decreasing temperature. The mean pupal duration was 14, 10 and 7 days at 24"C, 28$^{\circ}$C and32"C, respectively. Percent emergence was in range of 21% to 89% with higher percent emergence as thetemperature increased and both 28$^{\circ}$C and 24$^{\circ}$C was highest on SL, followed by PL, SPL and AD, but at24$^{\circ}$C the order was SPL, PL, SL and then AD. Preoviposition duration was 3.2 days at 24"C, 2.8 days at28$^{\circ}$C and 2.5 days at 32$^{\circ}$C. Adult longevity became shorter as the temperature increased from 6.4 to 3.9days. Male longevity was longer than that of female. Adults lived longest when they were reared on PL,followed by SL, SPL and AD. Total number of eggs laid per female varied from 803 to 1,441 regardlessof the treatments, but those were significantly more on natural foods than on AD. Number of eggs per eggmass was 97.4 at 24$^{\circ}$C 155.8 at 28$^{\circ}$C and 104.7 at 32$^{\circ}$C. Number of egg mass was 12.0, 6.7 and 11.3 at24"C, 28$^{\circ}$C and 32"C, respectively.4"C, 28$^{\circ}$C and 32"C, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.429-436
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• 2012

This study was conducted to examine the effect of feeding levels of concentrate feed on growth performance, meat quality and economic evaluation of Korean black goats. The 40 male Korean native goat were divided into four treatment groups T1 (1.5%), T2 (2.0%), T3 (2.5% feeding of concentrate feed body weight per day) and T4 (ab libitum) with ab libitum rice straw. Rice straw intake decrease as against feeding levels, however average daily gains were 22, 50, 69 and 94 g/day in T1, T2, T3 and T4 groups respectively levels (p<0.05). Dressing percentage were 41.77, 42.78, 46.12 and 49.78% in each group (p<0.05), also fat percentage were a significant increase according to feeding levels. In economic efficacy, T4 was higher than other treatment groups. In conclusion, both rice straw and concentrate feed ab libitum are good for feeding and management system on Korean black goats.

• Korean journal of applied entomology
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• v.51 no.1
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• pp.9-18
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• 2012

The size of infective $Steinernema$ $arenarium$ juveniles is variable and ranges from 724 to 1408 ${\mu}m$. Effects of harvest time and infective juvenile size on pathogenicity, development, and reproduction were examined in the last instar of the great wax moth, $Galleria$ $mellonella$. Harvest time of infective juveniles (IJs) of $S.$ $arenarium$ affected pathogenicity. IJs harvested at the 10th day from trapping were more pathogenic than those harvested the 3rd day from trapping. Mortality of $G$. mellonella also depending on harvest time, $i.e$, 100% died within 48h when IJs were harvested at the 10th day, without relation to size. However, mortality was 40% in the small size group (SSG) compared with 18% in the large size group (LSG) within 48h when IJs were harvested at the 3rd day. Establishment of $S.$ $arenarium$ within the host was different depending on IJ size. The number of established IJs was 1.8 in the SSG, 3.3 in the LSG, and 3.2 in the mixed size group (MSG) when IJs were harvested at the 3rd day, and 5.3 in the SSG, 7.4 in the LSG, and 7.6 in the MSG when IJs were harvested at the 10th day. The length of the female adult was 7,070.5 ${\mu}m$ in the SSG and 7,893.9 ${\mu}m$ in the LSG and that of the male was 1,460.5 ${\mu}m$ in the SSG and 1,688.2 ${\mu}m$ in the LSG when IJs were harvested at the 3rd day. The length of the female adult was 7,573.6 ${\mu}m$ in the SSG and 8,305.4 ${\mu}m$ in the LSG and that of the male adult was 1,733.4 ${\mu}m$ in the SSG and 1,794.4 ${\mu}m$ in the LSG when IJs were harvested at the 10th day. Harvest time and size of IJs did not influence numbers of progeny or size of IJS.

• Korean Journal of Organic Agriculture
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• v.16 no.3
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• pp.309-320
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• 2008

This study was conducted to determine the effects of different types of hilly pasture grazing on growth and meat quality in organic Korean black goats, and to obtain basic data for the production of organic goats. A total of 40 goats with similar age and BW were equally allocated to four dietary treatments in a randomized complete block design. Dietary treatments included grazing types of four different hilly pastures; T1: forages types, T2: organic forages types, T3: native plants types, and T4: browse types, respectively. The trial lasted for 174 days from 15th of May to 5th of November, 2007 in Livestock Genetic Resources Experiment Station, National Institute of Animal Sciences. At the end of trial, all animals were slaughtered to analyze carcass characteristics and meat quality. Average daily gain was significantly (p<0.05) higher for T1 treatments than for others. Dressing percentage was significantly (p<0.05) higher for T1 and T2 than for T3 and T4 treatments. Meat percentage of T1 treatments was significantly (p<0.05) higher than those of other treatments. For meat properties, crude fat content was highest in T3 treatments. Linoleate (18:2n6) and linolenate (18:3n3) contents tended to be higher in T1 than those of other treatments, while arachidonate (20:4n6) content tended to be higher in T3 and T4 than that of other treatments. Shear force was lower (p<0.05) for T3 than other treatments. For sensory results, juiciness and tenderness tended to be greater (p<0.05) in T2 and T3, and flavour tended to be greater (p<0.05) in T3 and T4. The results indicated that grazing in hilly pastures for organic Korean black goats was somewhat less in their performances and carcass characteristics, but not behind in the meat quality and physical characteristics as compared with the conventional regimen. Therefore, it would be expected that goats grazing in hilly pastures made it possible to produce organic animal products with a high safety and also might lead to increase of breeders income and consumers satisfaction.

• Korean journal of applied entomology
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• v.60 no.2
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• pp.255-262
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• 2021

The potato tuber moth, Phthorimaea operculella (Zeller) has been known as a quarantine pest of potato. This study investigated inhibition doses of electron beam irradiation (EBM) by comparing their effects on the development and reproduction and DNA damage of the insect pest. Eggs (0-12 h old), larvae (3^rd and 5^th instar), pupae (less than 1 d old after pupation) and adults (less than 1 d old after emergence) were irradiated with increasing doses of EBM. The EBM with 150 Gy could not completely prevent the hatchability of eggs and pupation of the hatched larvae. The hatchability from the irradiated eggs were 19.3%. However, adult emergence from the irradiated eggs were completely inhibited. When 3^rd and 5^th instar larvae were irradiated at 100 Gy, the adult emergence from the irradiated larvae and the fecundity of the adults were completely inhibited. When pupae and adults were irradiated at 300 Gy and 400 Gy, respectively, the hatchability of the F₁ eggs was completely inhibited. The alkaline comet assay on the level of DNA damage by EBM in P. operculella adults indicates that the EBM increased DNA damage level in a dose-dependent manner, and the damage was repaired in a time-dependent manner. These results may recommend EBM of 150 Gy as a phytosanitary treatment for P. operculella. However further confirmative study is required for the practical application of this EBM dose for P. operculella disinfestation.