• Journal of The Korean Society of Grassland and Forage Science
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• v.7 no.1
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• pp.18-24
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• 1987

This experiment was carried out to investigate the effects of the final cutting time and cutting height on the winter survival, regrowth, and carbohydrate reserves in stubble, and early spring yield of orchardgrass-dominated pasture before and after the winter season. The experiment was conducted at the experimental field of the Livestock Experiment Station, in Suwon, from October 1985 to early 1986. The results obtained are summarized as follows: 1. Regrowth of plant after the final cut increased significantly (P<0.05) with plot of the early cutting time (Oct. 10) and high cutting height at the final. For winter survival, cut plant should regrow over 15cm in plant height. Therefore limit cutting time and cutting height were forced to be on Oct. 25 and at 6-9cm, respectively. 2. Total water soluble carbohydrate (TSC) content in stubble after the final cut was not significantly changed by different cutting time and cutting height. 3. The percentage of dead plant after wintering was found to be high with plot of the late cutting time and low cutting height at the final cut (P<0.05). And the correlation between the percentage of dead plant after wintering and final plant height before wintering was significantly negathe (r = -0.728**). 4. Fresh and DM yield at the early spring after wintering were increased in the plot of the early cutting time and high cutting height (P<0.05) at the final cut. And significantly positive correlation was observed between the early spring yield and final plant height before wintering (r = 0.720**).

• Korean Journal of Veterinary Service
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• v.41 no.2
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• pp.91-95
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• 2018

Polioencephalomalacia (PEM) is a neurologic disease of ruminants diagnosed by pathological approach. There is very little information available to understand bovine PEM in Korea. In this study, we investigated the diagnostic rate and pathological features of PEM in 334 necropsied cases of cattle submitted to the Animal and Plant Quarantine Agency in Korea from 2015~2017. PEM was diagnosed only in 13 (3.9%) Hanwoo, the Korean native cattle, and sporadically occurred in our country. The disease was the most diagnosed in fall season, and the age of the cows ranged from 1 month to 3 year. In all PEM cases, softening, and yellow discoloration of the gray matter in the cerebrum and fluorescence at the sites using ultraviolet illumination were grossly observed. Microscopically abundance of glial cells with vacuolar large cytoplasm and neuronal necrosis were commonly observed. This study suggests that future studies are necessary to identify the cause and pathogenesis for the control of PEM in our country.

• The Korean Journal of Ecology
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• v.12 no.1
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• pp.1-7
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• 1989

We studied primary production, nitrogen and phosphorus dynamics in a salt marsh of Okryutung at Nakdong River estuary. The standing biomass in Phragmites longivalvis, Carex scabrifolia and Zoysia sinica stand was $5.48kg/\textrm{m}^2,{\;}1.94kg/\textrm{m}^2{\;}and{\;}1.95kg/\textrm{m}^2$, respectively. The peak above-ground biomass in each stand was $1.99kg/\textrm{m}^2,{\;}0.74kg/\textrm{m}^2{\;}and{\;}1.03kg/\textrm{m}^2$, respectively. Soil nitrogen decreased from the onset of growing seson till July, and then increased. Seasonal patterns of soil phosphorus were different from stand to stand. Nitrogen concentrations of above-ground plant tissus were quite different among the plant species at the very beginning of the growing season, however, they became similar as the plants grow. Seasonal pattern of phosphrous in C. scabrifolia roots was quite different from those other two species. Nitrogen absorbed by plants during season in P. longivalvis, C. scabrifolia and Z. sinicia stand was 224kg/ha, 111kg/ha, 156kg/ha, respectively. Phosphorus taken up by plants was 22kg/ha, 29kg/ha and 21kg/ha, respectively. Because the vascular plants growing at salt marshes can immobilize large quantities of nitrogen and phosphorus, salt marsh vegetation can be sued for preventing the pollution of coastal sea water.

• Horticultural Science & Technology
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• v.16 no.3
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• pp.377-380
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• 1998

In order to investigate the effects of foliage plants on the changes of indoor thermal- and hygro- environments, experiments were carried out in two rooms with similar physical factors. Changes of indoor environmental parameters according to the existence of plants, their arrangement methods, and the existence of wrapseal for protecting the loss of water from the pot soil were measured during certain periods in winter and summer season, using Pachira aquatica which is widely used as indoor plant and has higher photosynthetic and traspiration rate than other foliage plants. The data suggested that the existence of plants didn't affect directly on the indoor thermal environment, while relative humidity increased about 3~5%, regardless of season, by putting plants which had volume equivalent to 2.4% of room volume. In summer, there was no difference in increasing effect of relative humidity between parallel arrangement with window and spread arrangement in the room, but in winter the former arrangement was more effective than the later.

• Parasites, Hosts and Diseases
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• v.56 no.5
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• pp.477-485
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• 2018

Arthropod-borne viruses (Arboviruses) are transmitted by arthropods such as Culicoides biting midges and cause abortion, stillbirth, and congenital malformation in ruminants, apparently leading to economic losses to farmers. To monitor the distribution of Culicoides and to determine their relationship with different environmental conditions (temperature, humidity, wind speed, and altitude of the farms) on 5 cattle farms, Culicoides were collected during summer season (May-September) in 2016 and 2017, and analyzed for identification of species and detection of arboviruses. About 35% of the Culicoides were collected in July and the collection rate increased with increase in temperature and humidity. The higher altitude where the farms were located, the more Culicoides were collected on inside than outside. In antigen test of Culicoides against 5 arboviruses, only Chuzan virus (CHUV) (2.63%) was detected in 2016. The Akabane virus (AKAV), CHUV, Ibaraki virus and Bovine ephemeral fever virus (BEFV) had a positive rate of less than 1.8% in 2017. In antigen test of bovine whole blood, AKAV (12.96%) and BEFV (0.96%) were positive in only one of the farms. As a result of serum neutralization test, antibodies against AKAV were generally measured in all the farms. These results suggest that vaccination before the season in which the Culicoides are active is probably best to prevent arbovirus infections.

• The Korean Journal of Mycology
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• v.27 no.6 s.93
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• pp.420-423
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• 1999

A Sciarid fly, Lycoriella mali was a serious pest in commercial production of the cultivated mushroom, Pleurotus ostreatus. It was found in light trap and compost samples taken from mushroom houses during all growing seasons. The fly population 'was increased with the development of mushroom growth, the larvae occurred about 30 days after spawn inoculation in compost. The highest population was developed spring cultivation season (March to June) and decreased during summer season (August to September). The larvae feed on mycellium and compost; injury to the growing mushroom mycellium and the subsequent consumption of the primordia; they entered and tunneld sporospore stem and infect pinhead formation which would be resulted in decrease of mushroom yield.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.2
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• pp.195-200
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• 1995

The design of this field experiment was a completely randomized block arrangement, consisted of 16 treatments (Gliricidia sepium provenances) and 6 blocks as replications with 12 plants per provenance. Of the 16 gliricidia provenances, six were from Mexico (M), four were from Guatemala (G), and one each was from Colombia (C), Indonesia (I), Nicaragua (N), panama (P), Costa Rica (R), and Venezuela (V). After 12 months establishment the gliricidia were lopped regularly 4 times a year, twice during the 4 months wet season and twice during the 8 months dry season at 150 cm height. There was variation (p < 0.05) in stem elongation from 22 to 80 cm, leaf retained from 118 to 209%, branch number from 13 to 24, fodder yield from 1,015 to 1,671 g DW/plant and wood yield from 792 to 1,662 g DW/plant among the provenances; and such variations were affected by the seasons. Belen (N14), Retalhuleu (G14) and Bukit Bali (I) provenances were ranked first, second and third, respectively, measured in terms of leaf retention, stem elongation, fodder and wood yields during the wet and dry seasons.

• Research in Plant Disease
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• v.13 no.3
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• pp.204-206
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• 2007

In 2006 to 2007, the potential inoculum source of the anthracnose of sweet persimmon caused by Colletotrichum gloeosporioides was surveyed. The infected twigs, buds, dead twigs, petiole, leaves, dropped fruits were collected and tested for their possibility as overwintering inoculum. The detection rates of the pathogen from various parts of sweet persimmon tree were varied. When the collected samples were examined in April. Over than 93.3% of infected twig samples were harbored mycelia of C. gloeosporioides, and 46.7% of infected buds, 36.7% of dead twigs, 23.3% of petioles, and 16.7% of leaves were beared pathogenic fungus. No pathogenic fungus were detecded from healthy twigs and buds. Infected twigs and bud was important overwintering sites and formed conidia actively in next spring. The infected twigs, leaves, petioles, and fruits in growing season produced great number of conidia and caused active dissemination of the anthracnose disease in sweet persimmon. In growing season, all of the infected parts, such as twigs, leaves, petioles, and fruits produced pathogenic fungus.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.5
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• pp.515-522
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• 1995

The field experiment was carried out to study the growth and fodder yield of the Gliricidia sepium provenances in fence system in dryland farming area in Bali, Indonesia for 24 months. The design of the experiment was a completely randomized block arrangement, consisted of 16 treatments (Gliricidia sepium provenances) and 12 blocks with 10 plants per provenance. Of the 16 gliricidia provenances, six were from Mexico (M), four were from Guatemala (G), and one each was from Colombia (C), Indonesia (I), Nicaragna (N), Panama (P), Costa Rica (R) and Venezuela (V). After 40 weeks establishment the gliricidia were lopped regularly 4 times a year, twice during the four month wet season and twice during the eight month dry season at 150 cm height. There were variations (p < 0.05) in stem elongation from 10 to 121 cm, leaf retained from 48 to 105%, leaf shedding from 53 to 86%, branch number from 4 to 7, fodder yield from 281 to 648 g DW/plant, and wood yield from 53 to 179 g DW/plant; and such variations were affected by the seasons. Retalhuleu provenance of Guatemala (G14), Belen provenance of Nicaragua (N14) and Bukit Bali provenance of Indonesia (I) were ranked first, second and third, respectively, measured in terms of stem elongation, leaf retention, fodder and wood yields during the wet and dry seasons.

• Research in Plant Disease
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• v.7 no.1
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• pp.42-48
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• 2001

The effect of cultural, physical and chemical control methods on the population density of Meloidogyne arenaria second-stage juveniles (J2) and on fruit yields of oriental melon was investigated at Seongju Fruit Vegetable Experiments Station, Kyungpook province, Korea, for two years from 1999 to 2000. Crops used in a rotation prior to Oriental melon were rice, corn, sesame, and green onion. The physical methods used were either solarization, soil addition or soil drying, and a nematicide, fosthiazate of granular formula, was used as the chemical method, applying at a rate of 300g a. i./10 a. Growing rice in the rotation, solarization, and soil addition controlled the nematode disease most effectively, reducing the number of J2 by 90% and increasing fruit yields two times. However, the effects of these control methods on the J2 population were limited to the early growing season; the J2 population increased later, suggesting that additional control practices may be needed in the following season. The next effective control methods were use of corn in the rotation, the nematicide application, and soil drying. The nematicide application was effective only for the early fruit yield, but neither for the late nor for the total yields. Use of sesame or green onion in the rotation was not effective in controlling the nematode.