• Korean journal of applied entomology
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• v.32 no.3
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• pp.271-278
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• 1993

This experiment was carried out to elucidate the mfluence of honeybees pollinatIOn on yield and YIeld components of soybean at the Kyungbuk Provincial Rural Development Administration from 1990 to 1991. SIX soybean varieties were cultivated in net houses with and without bees. Italian honeybees(Apis melhfem L.) were used. The Vlsiting frequency of bees in net house wIth bees was 58% higher than that of field honeybees, and it was the highest at 10 A.M. during a day. Number of pods per plant and podding ratio of soybean were higher with bees compared with Wlthout bees, especially for the varieties Paldalkong and Dankyongkong. The number of seeds per pod was not significantly different between with bees and without bees, although the percentage of three seeded pod of varieties Danyeobkong and Muhankong and one seeded pod of varieties Hwangkeumkong and Milyangkong 'was increased. The percentage of three seeded pod of Paldalkong and Dankyeongkong, however, was decreased with bees compared with without bees. At the same time no varietal difference was found in two seeded pods between with bees and without bees. Yield of soybeans was increased 0 to 12 % with bees compared with that of without bees. Yield increase was the hIghest in Paldalkong and Dankyongkong. The ratIO of soybean hybrid plant was mcreased with-bees compared with that of without-bees, especially m Paldalkong and Dankyongkong. A negative correlation was found between the ratio of hybrid plant and the duration of flowering in soy¬beans.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.333-337
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• 2006

The damage aspects of soybean by common cutworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) at different larval density and different growth stage of soybean were studied in soybean field. The percent yield reduction(Y) of soybean infested by different densities of S. litura (X, no. of larvae/plant) under outdoor conditions for a three week period were estimated by the following equations: (1) Y = 1.655X - 6.025 ($R^{2}=0.952$) for the R1 (flowering stage); (2) Y = 0.725X - 0.475 ($R^{2}=0.986$) for the R3 (beginning pod stage); and (3) Y = 0.635X - 1.325 ($R^{2}=0.986$) for the R5 (beginning seed stage). Based on the relationships between the densities of S. litura larvae and the yield index of soybean, the number of larvae (2nd-3rd instar) which caused 5% loss of yield (Tolerable injury level) was estimated to as approximately 6.7 for the R1, 7.5 for the R5, and 10.0 per plant for the R5, respectively. Average soybean leaf areas consumed by 1st, 2nd, 3rd, 4th, 5th and 6th larvae of Spodoptera litura during 24 hr at $28^{\circ}C$ was 0.3, 0.7, 2.6, 4.0, 20.1, and $55.8\;cm^{2}$, respectively.

• Korean journal of applied entomology
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• v.55 no.1
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• pp.45-51
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• 2016

Thirty-seven species of insect pests were surveyed on different area blueberry farms in Jeonbuk province during 2013~2014. Six principal insect pests were found, including Dasineura oxycoccana Johnson, Aphis gossypii Glover, Scirtothrips dorsalis Hood, Ricania sp., Hyphantria cunea Drury, and Latoia consocia Walker. A. gossypii infestation was severe at Iksan and Jinan in middle May. S. dorsalis infestation was severe at all surveyed area in early June, which is the flowering season, and the degree of damage caused was higher in young plants. Ricania sp. was abundant in Jinan and Sunchang, and then appeared to spread across all areas in Jeonbuk. H. cunea had a tendency to concentrate in Iksan during June. Five species of Limacodidae was found, including L. consocia, which was dominant in all areas surveyed, with densities higher then those of the others four species. The degree of damage due to D. oxycoccana was higher in the plain areas (Iksan) than in the middle-mountain areas (Jinan, Sunchang). The rate of damage was 60~78% higher in young plant stages (i.e., those under 3 years of tree age) than in those over 5 years old (30~50%). Moreover, the rate of damage observed in greenhouses was 50~80% higher than that observed in the field (30~40%).

• Korean Journal of Plant Resources
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• v.8 no.1
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• pp.47-54
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• 1995

The ergot fungus requiers a rather long time for the incubation period for a disease and fungus tends to obstract the formation of the seeds. In order to do an experiment inoculated, a spore of ergot fungi into the florets was done 2-3 days before flowering. As a result, each trisomic types recognized the infection rate to be 90% to 100% so the trisomies of complete immunity was non existent in durum wheat, Triticum durum var. hordeiforme. However, the growth rate of large sclerotium than seeds differed mutually with each trisomic types. This tend to be sensitivity on the trisomies which has been the extra chromosomes of 2A, 4A and 7B in comparison with normal plant but the trisomies related to Tri-6A line was not forming the sclerotium of large size than seeds and grew outside the florets. Consequently, the resisitant gene against ergot fungi was considered to be existing on the chromosome 6A. The ergot fungi requires a long time for the incubation period until it is taken away from infection. The essential effect of resistant gene did not surmise on the chromosome 6A that gene concerned with the physiological effect to restrain the growing up of a ergot fungi in the growing process of plants.

• Korean Journal of Plant Taxonomy
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• v.44 no.1
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• pp.13-17
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• 2014

Two naturalized plants belonging to Asteraceae (Compositae) were collected in Gangwon-do and Jeju-do. Euthamia graminifolia (L.) Nutt., a taxon of unrecorded genus Euthamia Nutt., was found in Inje-gun, Gangwon-do. This species can be distinguished from Solidago japonica Kitam. and S. gigantea Aiton by punctate, entire leaves and disc corollas without vein. Its Korean name was given 'Mi-yeok-chwi-a-jae-bi' because it shows similar external appearances with that of the Mi-yeok-chwi (Solidago japonica Kitam.). Gamochaeta pensylvanica (Willd.) Cabrera was discovered in Jeju-do. It can be distinguished from G. purpurea (L.) Cabrera by withering basal leaves at flowering and relatively short inner phyllaries. This taxon was named 'Mi-guk-pulsom- na-mul' in Korean by considering its specific epithet.

• Korean Journal of Plant Taxonomy
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• v.44 no.4
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• pp.281-287
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• 2014

The present study was conducted to understand the growth pattern, pollinators and their frequency of visits of Euphorbia helioscopia population which is located at Tongyoung areas in Korea. The vegetative parts of the species grow early in March, and flowering begins in the middle of the month, and pollination was completed at the mid of April. As a typical form of early spring type, the fruits of E. helioscopia were matured between early in April and May, and the upper parts of plants were disappeared between May and June. During the blooming season about 11 insects species which belong to Diptera, Hymenoptera, Coleoptera and Heteroptera were the most common groups found on this plants. Among them the species of Diptera are the most dominant pollinators for E. helioscopia which is concordant to previous reports in Euphorbia species. Despite of significant numbers of insect visitors in Euphorbia species being reported, E. helioscopia attracts only 11 insect species in study areas, and the paucity of species probably associates with the insect fauna in Tongyoung areas or typical patterns of early spring bloomer of Euphorbias. We observed majority of Diptera species to visit in the morning, and the frequency of visit decreased in the afternoon. Thus, it suggests that the visiting activity of Diptera species is not associated with the temperature increase which was reported in Euphorbia species. However, the number of the cyathium during the blooming season is likely to be related to the frequency of visit of pollinators in E. helioscopia.

• Korean Journal of Plant Taxonomy
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• v.43 no.2
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• pp.81-89
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• 2013

In general, studies of aerial parasitic plants known collectively as mistletoe have been carried out to investigate their ecological and agricultural characteristics. However, with the recently increased level of interest in medicinal resources, research on different types of Korean mistletoe has also increased. This study was carried out to review the work on the taxonomy and ecology of Korean mistletoe in preparation for the industrial use of these plants in the future. Mistletoe types are flowering plants belonging to Santalales, which exist in the form of parasites on the branches of trees or shrubs. In Korea, five taxa of four genera in two families of mistletoe exist: Viscum coloratum (Komarov) Nakai f. coloratum, Viscum coloratum (Komarov) Nakai f. rubroaurantiacum (Makino) Kitagawa and Korthalsella japonica (Thunb.) Engl. in Santalaceae, along with Loranthus tanakae Franch. et Sav. and Taxillus yadoriki (Sieb. ex Maxim.) Danser in Loranthaceae. As taxonomic studies of these species remain insufficient and given that the distribution ranges of these species are very wide, further observations pertaining to the morphological variations in each species are necessary. The distribution of mistletoes is known to be determined by the host specificity, the interval between the hosts, the environmental condition, the habits of the host plant, the eating characteristics of mediators in the area, and their habitat selection features.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.444-450
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• 1995

It was very hard to gather the seeds of Eleutherococcus senticosus Max. known as a medicinal plant for they tend to drop under the high temperature condition during the summer period in Korea. Therefore, this study was conducted to select seed production site for Eleutherococcus senticosus in Korea, comparing the climate of Hokkaido of Japan, in which the seeds have been produced, with that of various place in this country. It was low that the average maximum temperature during the hottest summer two months (July and August) as a 24.4$^{\circ}C$ in Hokkaido and 21.2$^{\circ}C$ in Daegwanryeong compared with 27.4$^{\circ}C$ in Changsu. Especially in Daegwanryeong, average maximum temperature from June to September remained as low as 21$^{\circ}C$. Effective accumulated temperature(>5$^{\circ}C$) was 807$^{\circ}C$ in Hokkaido and 964$^{\circ}C$ in Daegwanryeong during the ripening period. Monthly sunshined hours from July to August were 121.7~128 hours in Daegwanryeong and 83.5~85.4 hours in Hokkaido. The Eleutherococcus senticosus sprouts at 8.5$^{\circ}C$, comes to flowering season in mid-August, and ripens during late-August and October in Hokkaido, the climate of which is similar to that of Daegwanryeong.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.211-215
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• 2002

This study was carried out to find out the optimum harvesting time on the basis of physiological characteristics, yield and commercial value in four years old ginseng. For this purpose, the changes of agronomic growth characteristics of the aerial and underground parts with different growing stages were examined with fourth year ginseng. The leaf growth was dramatically increased from the mid-April (shooting stage) to the mid-May (flowering stage), and the growth was nearly completed by the mid-May, but the stem growth continued by the mid-August. The weight of fresh root decreased from the April (20.7g) to the June (18.2g), but increased from the June to the October(45. 1g). The yield of fresh root per "Kan" was 1.5 kg, 1.2kg and 1.3kg at the April, the May and the June, respectively, thereafter continually increased to 2.9 kg of the October, which showing the maximum yield. In conclusion, the ginseng root was generally harvested from the September to the October at farm-house, but it had better be harvested after the mid-October rather than from September to October considering the weight of dry root and the yield of fresh ginseng.h ginseng.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.3
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• pp.263-268
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• 1981

Fourteen hundred and one landraces of sesame cultivated in Korea were collected and evaluated for their major agronomic characters and yield potential under conditions of May 15 sowing, 50\timesl5cm planting density and 4-3-2 kg/l0a of N-P_2 $O_{5}$-K_2 O application in Suweon in 1977. Seventy nine percent of the collection had white seed coat color, and 29% was brown. One capsule type with two rooms-four cells was 75%, one capsule type with four rooms-eight cells was 20%, and three capsule type with two rooms-four cel1s were 5% of the varieties collected, But, two one-capsule type varieties with three rooms-six cells were also found. Days to flowering from emergence were long in the varieties collected in the central northern area, but short in the varieties collected in the southern area. Number of capsule per plant was more in the central northern varieties than in the southern varieties. Number of branch per plant was more in the one capsule type varieties with two rooms-four cells than in the three capsule type varieties with two rooms-four cells and in the one capsule type varieties with four rooms-eight cells. There were significant corelations between number of capsules per plant and grain yields in the one capsule type varieties with four cells. Grain yields had significant correlation with number of capsules per plant and number of branches per plant.