• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.4
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• pp.315-319
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• 1990

In order to determine the optimum sowing date of Cassia tora L., ecological characters, components and yield were investigated under vinyl-mulching and non-mulching condition. Emergence date and maturation date of vinyl-mulching condition were earlier than those of non-mulching condition. especially with maturation date being about 30 days earlier, Under vinyl-mulching condition, length of stem and pod were longer, number of branches, pods and seeds per plant were increased, stem diameter was thicker, and weight of 1000 grains was heavier. Seed yield per 10a under vinyl-mulching was twice as high as that of non-nulching condition. As sowing date was delayed, the maturation date was progressively delayed. At sowing date of April 10, plants showed the longest in length of stem and pod, the largest in number of pods per plant and number of grains per pod, and the highest in weight of 1000 grains and seed yield. Judging from the results, optimum sowing of Cassia tora L. appeared to be April 10.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.200-222
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• 1992

The results of recent researches for improvement of seedling stand in direct seeded rice on the dry paddy in Korea were summarized as the following ; a variety to be cultivated should be chosen the characteristics of high percentage germination under low temperature, shorter period of shoot emergence, and better growth of the mesocotyl and shoots. Meanwhile, there was 40% increase in seedling stand at the treatment of removal of the seed awn under using the drill seeder. After seeding the rice seed covered with soil of 3cm depth was better seedling emergence and also there was the hightest seedling emergence at the 70% of moisture content of the soil. In addition, the application of the Release containing GA 10% enabled to increase the seedling stand and furthermore it was effective under deep seeding depth. The optimum seeding date should be seeded around May 10 when mean air temperature is above 12-13$^{\circ}C$ so that may establish more less 70% in seedling stand. Based on an appropriate seedling stand of 150/$m^2$, the optimum seeding rate was 5kg/10a. It was the best in seeding method using drill seeder and the most desirable recommended seeding method was the drill seeder in terms of seedling stand. In order to improve seedling stand water management was more effective in canal irrigation and in drainage at 6hr after irrigation following by the seeding process. On the other hand, for the increase of seedling stand under flooded condition a variety might have characters being better germination at low concentration of dissolved oxygen and vertically deeper growing of the crown root. Also, seedling stand was able to increase with the seed coating of $CaO_2$in the flooded soil. It was possible to be seeded on the early part of May being mean air temperature of avove 10$^{\circ}C$ and the optimum seeding rate was 5kg/10a. For an effective water management water would be flooded up to 3cm depth for 2-3 weeks after seeding. The rice plant grown under the direct seeded cultivation might be not so much strong in lodging resistance compared to that grown under the transplanting and moreover direct seeded rice cultivation under flooded condition would be more weak growth of the rice plant than that on dry paddy. Meanwhile, the lodging would be affected by the seeding rate, the soil depth after seeding. and seeding method even in the same variety. In particular, roots in the lodging pattern of direct seeded rice cultivation under flooded condition were largely distributed on the soil surface so that resulted easily in the lodging. In general, the lodging resistance would be greater as seeding rate and amount of N fertilizer application are lower and soil depth after seeding is higher. Among the introduction of different seeding method the high ridged drill seeding method on dry paddy soil resulted in the lowest in the lodging index and also it was lower in the drill seeding method than in the scattering seeding method under flooded condition. In case of more than 150 seedlings per $m^2$ there was a severe lodging due to high lodging index at the 3rd and 4th internodes. The effective lodging prevention was able to at the treatment of the Inabenfide at 45 days before heading and the Uniconazol at 15 days before heading which caused the shortage by 10-15cm in culm length. Also, fertilizer management using split application of nitrogen would be contributed the reduction of lodging at the rate of 20-30-20-20-10%(basal-5th leaf stage-7th leaf stage-panicle initiation stage-heading stage) on the dry paddy soil.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.57-61
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• 2005

The objectives of this study are to illustrate an alternative housing type responding to the social requirements and customers' needs, to suggest the improvement plan for the related laws and regulations through survey of the actual condition for housing buildings such multi have been raised in classification due to that the existing law systems including the current use classification of residential buildings have been defined unclearly. Especially, various social problems have yielded in line with emergence of the housing type which is not legally classified as residential however used for the living purpose practically. Current zoning planning and related law system have rigidity. So, It is required to introduce a flexible classification system which protects the residential environment based on the housing purpose, function and habitability and provides correspondence between residence and ownership/management method. The legal classification system should be revised in a way that the housing use classification corresponds with the zoning system through breakdown of the use classification system

• The Korean Journal of Community Living Science
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• v.17 no.3
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• pp.89-97
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• 2006

This study was conducted to compare soybean growth and yield and the degree of weed emergence according to no-tillage and conventional tillage system in two different drained paddy fields, loam of Chilgok series and silty clay loam of Deokpyeong series. In both soil conditions, the maturing time of the soybeans by the no-tillage system was two days earlier than that by the conventional tillage system. In the loam of Chilgok series, the stem length of the soybeans in the no-tillage system was 5.7 cm longer than that in the conventional tillage system. The miss-planted rate and diseased plants of black root rot (Calonectria iliacola) in the no-tillage system were 9.2% and 2.8% lower, respectively than those in the conventional tillage system. Also, the nodulation and seed yield in the no-tillage system were 32% and 13% more, respectively, than those in the conventional tillage system. In the silty clay loam of Deokpyeong series, the stem length of the soybeans in the no-tillage system was 4.6cm shorter than in the conventional tillage system. The diseased plants of black root rot (Calonectria iliacola) in the no-tillage system were 4.2% lower than those in the conventional tillage system. Also, no significant difference in the seed yield between the no-tillage and conventional tillage systems was observed. On the other hand, there was a lower occurrence of weed in the no-tillage system than in the conventional tillage system, and the income increased by 19% owing to yield increase and reduced management costs.

• Korean journal of applied entomology
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• v.17 no.4 s.37
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• pp.187-191
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• 1978

This experiment was conducted to determine the optimum temperature and day-length condition for laboratory multiplication of Green Rice Leafhopper, Nephotettix cincticeps Uhler, and to obtain basic information for deriving temperature dependent growth rate function. The insects which were reared in $33-35^{\circ}C$ have relatively short nymphal periods and high adult emergence rate compared with the insects which were reared in $27-29^{\circ}C$ The adults which emerged in $35^{\circ}C$ laid significantly smaller number of eggs than the adult reared in $27-29^{\circ}C$ during their nymphal stage. Day length in $29^{\circ}C$ did not have any influence to the nymphal growth, adult emergence rate and egg laying of the insect. The growth rate of the insect did not have linear relation with rearing temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.19
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• pp.100-131
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• 1975

To obtain basic information on the improvement of naked barley production. and to clarify the relation-ships between yield or yield components and some meteorogical factors for yield prediction were the objectives of this study. The basic data used in this study were obtained from the experiments carried out for 16 years from 1958 to 1974 at the Chon-nam Provincial Office of Rural development. The simple correlation coefficients and multiple regression coefficients among the yield or yield components and meteorogical factors were calculated for the study. Days to emergence ranged from 8 to 26 days were reduced under conditions of mean minimum air temperature were high. The early emergence contributed to increasing plant height and number of tillers as well as to earlier maximum tillering and heading date. The plant height before wintering showed positive correlations with the hours of sunshine. On the other hand, plant height measured on march 1st and March 20th showed positive correlation with the amount of precipitation and negative correlation with the hours of sunshine during the wintering or regrowth stage. Kernel weights were affected by the hours of sunshine and rainfall after heading, and kernel weights were less variable when the hours of sunshine were relatively long and rainfalls in May were around 80 to 10mm. It seemed that grain yields were mostly affected by the climatic condition in March. showing the negative correlation between yield and mean air temperature, minimum air temperature during the period. In the other hand, the yield was shown to have positive correlation with hours of sunshine. Some yield prediction equations were obtained from the data of mean air temperature, mean minimum temperature and accumulated air temperature in March. Yield prediction was also possible by using multiple regression equations, which were derived from yield data and the number of spikes and plant height as observed at May 20th.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.112-116
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• 1999

In theprevious Hizikia cultivation, holdfasts were threw into the sea after harvesting in May; the young thalli(5$\~$10cm in length) of Hizikia are annually collected from natural bed by seed collectors for the cultivation, resulting in a ruined natural populations. Therfore, the reuse method of holdfasts by regeneration capability of Hizikia fusiformis, was investigated. The effects of emergence on the growth of regenerated thalli from holdfasts over 6 months of outdoor culture from May to November, 1995. The vegetative growth from the holdfasts was good under the emergence of 3hrs/day on the air than 0, 1 and 2hr/day. The regeneration of holdfasts was determined by measuring total length, number of stipe and weight. The growth was facilitated under the exposure condition of 1$\~$3 hrs/day on the air. Outdoor cultivation for the comparsion of to artifical natural seeds were conducted from December 1995 to May 1996. There was no significant differences(0.05< P) between the two kinds of seeds. Therefore, artificial seed maybe used as a replacement for the natural seed in Hizikia cultivation. From the results, an useful method was established to obtain young fronds for the cultivation using the reuse method of holdfast, to conserve the natural population of Hizikia.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.3
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• pp.249-258
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• 2007

Experiments were conducted with aims to (1) estimate the biomass yield potential, (2) characterize the biomass and digestible dry matter production, and (3) reveal the characteristic seedling establishment of a whole crop rice variety, Nogyangbyeo, in dry- and wet-seeded rice. Maximum aboveground total biomass of Nogyangbyeo was 18 t $ha^{-1}$ in dry-seeded rice and 20 t $ha^{-1}$ in wet-seeded rice. Biomass yield potential of Nogyangbyeo was lower than that of Dasanbyeo. Comparatively, Nogyangbyeo was straw-dependent and Dasanbyeo was grain-dependent for biomass accumulation. Percentage of digestible dry matter (DDM) was higher in panicles than straw. Digestible dry matter yield was determined mainly by biomass yield rather than DDM percentage. Number of seedling establishment in Nogyangbyeo was $73m^{-2}$ in dry-seeded rice and $109m^{-2}$ in wet-seeded rice. Poor seedling establishment of dry-seeded Nogyangbyeo in the field condition was the result of low seed germination under low temperature and poor seedling emergence by deep sowing. Low seedling emergence rate of Nogyangbyeo was attributed mainly to slow elongation growth by slow leaf development and partly to mesocotyl and 1st internode lengths, not to genetically defined leaf length. The slow elongation growth of Nogyangbyeo was the same even in the high daily mean temperature of $24^{\circ}C$. Results suggest DDM yield in rice can be improved simply by increasing biomass and whole crop rice varieties should be adaptable to direct-seeding.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.341-344
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• 2005

Courtship behavior of the sweet potato leaf worm, Aedia leucomelas L. (Lepidoptera: Noctuidae) was observed under laboratory condition. Behavior of antennal Probing and wing fanning in presence of opposite sex was observed in dark room. Both male and female exhibited similar behavior, fanning wing and raising antenna before male flew toward female. Some of moths began raising antenna 20 minutes into scotophase, and 20 minutes later both sexes started to exhibit spectacular behavior, fanning the wings intermittently in high frequency as if producing sound for attracting opposite sexes. They began mating about one day after emergence and mating activity was peaked from 4 to 6 days after emergence. Multiple mating was observed and the copulation lasted 207 minutes in average. There was an evidence that female emit sexual communication signal and male respond to it, and it seemed that the sound production is possibly a part of the courtship behavior of sweet potato leaf worm.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.115-120
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• 1981

Effect of soil water on the growth of Panax ginseng(2 years old) was investigated through pot experiment. the results were as follows. 1. Optimum soil moisture content for root yield appeared to be 65.5% of field capacity(22.1% fresh weight basis) and at 31.5%(10.7% fresh weight basis) relative growth rate was nil. 2. Under suboptimum condition of soil moisture, emergence of shoot and leaf unfolding was delayed. The rate of emergence of shoot and leaf area was also decreased while missing shoot rate was increased. 3. Root yield was positively correlated with leaf area per plant(r=0.91 **), stem diameter (r=0.73**), stem length(r=0.71 **) fresh top yield(r=0.93**) and negatively with missing shoot rate(r=-0.77**). 4. Fresh root weight showed negative correlation(r=-0.80**) with water content of root indicating that tissue is more compact when grown at sufficient water.