• Asian Journal of Turfgrass Science
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• v.13 no.1
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• pp.1-20
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• 1999

This study was carried out to investigate the interaction between productivity and light condition and to analyze the material productivity and productive charactaristics under different hours of light in Zoysia japonica. 1. Rate increasement of leaf number and total leaf length was remarkably high at the early growth stage in the control and 9 hour light treatment. The rate gradually decreased as growth proceeded. But 3 hour treatment was very low in the rate from its early growth stage through the whole test period. 2. The increasing rate of leaf area ratio (LAR) in all the experimental plots was remarkably high at the early growth stage after transplanting the grass. The shorter photoperiod resulted remarkable lower increasement of LAR. 3. The rhizome growth rate of the 9 hour photoperiod was high contrast to the 3 hour photoperiod treatment. The increasing rate of node number was also showed similar trend. 4. Chlorophyll content was very high at the 36 days after transplanting and then decreased gradually. Chlorophyll content on 3 hours photoperiod plot severely decreased. The ratio of chlorophyll a to b was decreased significantly at short day treatment. 5. The content of soluble sugar was increased at shorter photoperiod. The highest ratio of sugar content was on August, 28 by HPLC method. Such a result was attributed to accumulation of sugar in spite of low synthesis of ploysacchrides, translocation by low consumption. 6. The increasing rate of standings in all light treatment was high at the early growth stage after transplanting. Short photoperiod treatment by 3hour showed especially low prganic productivity on Zoysia japonica.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.1-16
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• 1985

This experiment was conducted to study sex expression and subsequent changes in protein and peroxidase after three cultivars of cucumber plants were treated with ethephon and gibberellin. The three cultivars of cucumber used in this study included 'Sayeup' (monoecious type), 'Sinrokdadaki' (gynoecious type), and 'Seonghowon' (intermediate type). The ethephon at 250 ppm and gibberellin at 100 ppm were treated at the 2-leaf and 4-leaf stages, and subsequent sex expression and changes in protein contents, peroxidase activities and isoperoxidase banding patterns by disc polyacrylamide gel electrophoresis were studied. The results can be summarized as follows: 1. Ethephon treatment slightly increased number of pistillate flowers and significantly decreased number of staminate flowers in the three cultivars, while gibberellin treatment significantly increased number of staminate flowers in both gynoecious 'Sinrokdadaki' and intermediate 'Seonghowon' and did not increase number of staminate flowers in monecious 'Sayeup' 2. There were some differences among three cultivars in protein contents, protein banding and isoperoxidase banding patterns of seeds and germinating seeds. However, it was not obvious to differentiate monoecious from gynoecious cultlvars by these characters. 3. Protein contents in the leaves. and stem apex after ethephon and gibberellin treatment increased gradually at the 2-leaf stage, but decreased at the 4-leaf stage. Protein contents in stem apex at the 4-leaf stage without treatment were much higher in 'Sinrokdadaki' and 'Seonghowon' than in monoecious 'Sayeup'. Protein contents in the stern apex at the 4-leaf stage were increased in the ethephon-treated monoecious 'Sayeup' and decreased in 'Sinrokdadaki' and 'Seonghowon' compared with untreated plants. 4. Peroxidase activities in the leaves and stem apex gradually decreased at the 2- leaf stage, but increased at the 4-leaf stage. Peroxidase activities in stern apex at the 4-leaf stage were significantly increased by ethephon treatment. 5. The number of protein bands in the three cuitivars after treatment gradually decreased in leaves and stem apex at the 2-leaf stage, but increased in the 4-leaf stage. The protein banding pat terns of stern apex of the ethephon-treated monoecious 'Sayeup' at the 4-leaf stage were gradually shifted to the banding.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.203-211
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• 1980

The pattern of blast disease incidence of Tonsil-line rice varieties derived from the cross between Indica and Japonica type was quite different from that of Japonica-type rice varieties. The former showed discontinuity between the incidence of leaf blast and panicle blast; the incidence .of leaf blast was slight, while that of panicle blast was very severe. Different level of nitrogen fertilizer applied influenced significantly the incidence of leaf blast but influenced slightly the incidence of panicle blast of Tongil-line rice varieties. The infection percentage of panicle blast of Tongil-line rice varieties was about $90\%$ and most of them were infected in leaf sheaths during booting stage, but infection of panicle blast of Japonica-type rice varieties in leaf sheaths during booting stage was very low, only about $3\%$. Infection route of panicle blast in leaf sheaths during booting stage, microflora in leaf sheaths, and specific susceptibility of young panicle to blast disease were investigated in the epidemiological point of view.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.223-231
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• 1994

To investigate effects of water stress on leaf water potential, nitrate reductase activity and abscisic acid content, Paldalkong, Saealkong and Danyeobkong were subjected to water stress by polyethyene glycol(PEG, MW=6,000) in the water culture and withholding irrigation in soil culture. Leaf water potential and nitrate reductase activity decreased with increaseing of PEG concentration in the water culture. These were higher at 3rd and 5th leaf stage than at 1st leaf stage. Leaf water potential showed no significant differance among the varieties, but nitrate redutase activity was higher in Paldalkong than in Saealkong and Danyeobkong. Leaf water potential and nitrate reductase activity decreased approximately 2.2 times (-1.67 MPa/-0.75MPa) and 47%(3.1${\mu}$ mole nitrite/g.DW/hour/15.9${\mu}$ mole nitrite/g.DW/hour) to control, respectively, after 3 days from water stress treatment in the soil culture. According to increasing PEG concentration, abscisic acid content increased in the water culture and was higher at 5th leaf stage than at 1st and 3rd leaf stage. Paldalkong showed the highest abscisic acid content. Abscisic acid content increased approximately 1.7 times (9.9nmole/g.DW/5.7nmole/g.DW) compared to the control after 3 days from water stress treatment in the soil culture.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.451-457
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• 1983

This study was conducted to estimate the effect of the drought on the changes of chlorophyll, protein and proline content of upper three leaves, and the grain yield components of barley plant (CV. baegdong) subjected to water stress at four stages: late vegetative, boot, anthesis early grain filling. 1. In comparison with leaf posititions in water stress, the first leaf below flag leaf maintained the highest relative turgidity, chlorophyll and protein content and showed the least proline accumulation. And, in terms of growth stages in water stress, chlorophyll was shown to be highest at anthesis stage, protein being highest at boot stage and proline being least at boot stage. 2. In boot stages, culm and spike length, and Number of grains per spike were remarkably decreased. And the weight of 1000 grains was at least level in the early grain filling stage, and also the grain size was comparatively decreased at boot and two following stages. 3. The protein content of grain by water stress, apart from early grain filling stage, was not significantly affected by water stress at different growth stages. 4. The rate of sterility was particularly increased at boot and anthesis stages. 5. It was eventually concluded that the boot stage among four growth stages, and the flag leaf in 3 leaf positions were mostly damaged by water stress at reproductive growth stage.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.25-30
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• 2004

Rice seedlings were used to examine the effect of UV-B radiation on leaf elongation and development. Leaf elongation in both rice seedlings showed differently depending on each leaf age. UV-B radiation strongly reduced leaf elongation, 58-66% compared to without UV-B radiation, of two rice seedlings, therefore, those seedlings could not grow further. Both control and plants grown under UV-B regime showed a diurnial fluctuation in growth rate, showing maximum growth during the light period and minimum during the dark period. Leaf growth at the third leaf stage by UV-B treatment was considerably reduced by 1.7-fold than the control whereas at the fifth leaf stage was not changed. Hydrogen peroxide was considerably increased in the second phase of UV-B-induced response as catalase and peroxidase are deactivated with an increase of UV-B radiation.

• Journal of Sericultural and Entomological Science
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• v.32 no.2
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• pp.113-117
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• 1990

The recovery of mulberry from a late frost (April 24 to 27) was investigated for four varieties : Kaeryangppong, Cheongilppong, and Jamsang 21 in Cheongju area, Chungbuk Province. 1. Unfavourable meteorlogical conditions for recovery of mulberry followed the early late frost : lower than normal temperatures in mid-April, less sunshine in early and mid-Jay, lower temperatures and early and less precipitation in late-May, and less precipitation than normal in early June. 2. Jamsang 21 grew to the 2-3 leaf stage first, at which time Kaeryangppong and Jamsang 22 were at the 1-2 leaf stage, and Cheongilppong was at the swallow-bill shape-1 leaf stage. 3. The first leaf stage occurred on May 12, 15 days after the frost and, 19 days later in an average year. The difference lasted until the harvesting season, the 6 leaf stage. 4. Young shoot length was 50-58% of that in 1989. Kaeryangppong was the shortest at 50% and the Jamsang 21 highest at 58% of 1989 values. 5. Leaf number was 52-67% that in 1989. Kaeryangppong was the lowest at 52% and the Jamsang 21 highest at 67% of 1989 values. 6. Young shoot and leaf weight was 44-63%, and leaf weight 39-61%, compared to 1989. Kaeryangppong and Cheongilppong were the lowest, Jamsang 21 and Jamsang 22 were the highest, compared to 1989 data. 7. Young shoot length was 50-58% compared with 1989. Kaeryangppong was the lowest as 50%, the highest Jamsang 21 as 58%. 8. Number of leaf was 52-67% compared with 1989. Kearyangppong was the lowest as 52%, the highest Jamsang 21 as 67%. 9. Young shoot and leaf wight was 44-63%, and leaf weight was 39-61% compared with 1989. Kaeryangppong was the lowest, lowest, Jamsang 21 was the highest, Cheongilppong was similar with Kaeryangppong and Jamsang 22 was similar with Jamsang 21. 10. Rate of young shoot and leaf weight to total weight decreased from 75% in 1989 to 55-61% in 1990. Rate of laef weight to young shoot decreased from 72-82% to 67-71%, showed 5-10% decrease. 11. Leaf yield decreased highly in Jamsang 22 as 57% compared with 1989. Kearyangppong 61%, Jamsang 21 64%, Cheonglppong 72%. Leaf yield was 827kg/10g in Kaeryangppong, 1, 000-1, 050kg/10a in the other varieties.

• Korean Journal of Environmental Agriculture
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• v.1 no.2
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• pp.123-128
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• 1982

This study was carried out to investigate the effect of ozone gas on paddy rice at the different growth stage. Seokwang variety of rice plant was exposed to 0.5 ppm ozone gas for 4 hours at rooting, maximum tillering, ear formation and heading stages. after ozone gas fumigation, damage symptom, percentage of destroyed leaf, chlorophyll content and peroxidase activity of rice plant were observed. The results obtained are as follows. 1) Typical symptom of ozone gas damage appeared greyish or reddish brown subtle spots within rice leaf vein. 2) Yield loss by ozone gas exposure at different growth stage was in the order of maximum tillering stage>rooting stage>ear formation stage>heading stage. 3) Chlorophyll damage and leaf destruction was the highest at maximum tillering stage, while damage of leaf and chlorophyll were not found at heading stage. 4) The damage by ozone gas fumigation was higher at the growth stage with higher N content in plant, and N content was decreased after ozone gas exposure.

• Journal of Information Processing Systems
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• v.16 no.3
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• pp.663-676
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• 2020

Plant leaf classification is a significant application of image processing techniques in modern agriculture. In this paper, a multi-granular angle description method is proposed for plant leaf classification and retrieval. The proposed method can describe leaf information from coarse to fine using multi-granular angle features. In the proposed method, each leaf contour is partitioned first with equal arc length under different granularities. And then three kinds of angle features are derived under each granular partition of leaf contour: angle value, angle histogram, and angular ternary pattern. These multi-granular angle features can capture both local and globe information of the leaf contour, and make a comprehensive description. In leaf matching stage, the simple city block metric is used to compute the dissimilarity of each pair of leaf under different granularities. And the matching scores at different granularities are fused based on quotient space theory to obtain the final leaf similarity measurement. Plant leaf classification and retrieval experiments are conducted on two challenging leaf image databases: Swedish leaf database and Flavia leaf database. The experimental results and the comparison with state-of-the-art methods indicate that proposed method has promising classification and retrieval performance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.55-59
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• 1993

Essential oil components and contents were investigated at different growth stages and organs of Schizonepeta tenuifolia Briquet. The content of essential oil different by growth stages and organs and the amount of essential oil at leaf was higher than any other organ. The content of essential oil at leaf and spica were increased by long growth period. The d-menthone and l-pulegone were maj or components of essential oil and contain 51-76% of total essential oil at leaf and spica. In the early stage leaf. l-pulegone was major component of essential oil but d-menthone was major components in the late stage leaf.