• Journal of Ginseng Research
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• v.22 no.2
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• pp.102-113
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• 1998

This experiment used chlorophyll fluorescence techniques to assess the effect of irradiant during leaf development on photoinhibition of photosynthesis in Panax ginseng. Seedlings of p. ginseng were grown in the 91asshouse at four shade levels. The maximum mid-day irradiant in each treatment between emergence (January 4) and completion of the experiment (February 25) was 1220, 485, 235, 125 $\mu$mol/$\textrm{m}^2$/s. To assess the rapidity of photosynthetic readaptation to changes in light levels, fluorescence parameters (Fo, F, Fm, Fm', AF/Fm;, Fv/Fm) were measured for three days before and after transfer of plants (on February 21) from each light treatment into each of the other light treatments. Before transfer, dark adapted values of Fv/Fm in the 1220 (0.699) and 485 (0.739) treatments were different from each other and lower than values in the 235 (0.764) and 125 (0.768) treatments, indicating mild photoinhibition. Patterns of change in F during the day also differed between treatments, with low light treatments tracking irradiant levels, but F in the high light treatment (1220) declined in the morning, presumably due to fluorescence quenching. Although plants grown at high irradiant had relatively low photosynthetic efficiency, relative electron transport rate was greater than in lower irradiant treatments. After transfer, plants adopted the daily pattern of change in F of the treatment to which they were moved with little change in absolute levels of F, except in plants transferred from the highest (1220) to the lowest light level (125), where F increased over the course of the three days following transfer. After plants were transferred, Fm' converged on values similar to those in plants raised in the treatments to which they were moved. Values of Fv/Fm in plants moved from low to high light declined dramatically, but there was no decline in plants from 485 moved to 1220. Values of Pv/Fm in plants that were moved from high light to lower light increased to values above those recorded in plants raised in the lower light treatments. Reductions in quantum efficiency caused by photoinhibition at high irradiant may be more than compensated for by higher electron transport rates, although evidence suggests that under high irradiant this tends to be balanced by reduced leaf area and earlier senescence. Chlorophyll fluorescence techniques appear capable of indicating effects of irradiant induced stress in ginseng, yielding results comparable to those obtained with gas exchange techniques but in less time and with greater replication.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.28-35
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• 1998

Cyhalofop/bentazon ME and pyribenzoxim EC herbicides were originally developed as foliarapplied herbicides to control weeds at 4-5 leaf stages of barnyard grass 20-25 days after seeding (DAS) in direct-seeding culture but further possible utilization of these two herbicides earlier than 3-4 leaf stages of rice were evaluated for a field where early weed infestations might be severe. The application of cyhalofop/bentazon ME and pyribenzoxim EC at right after rice emergence and the 2-3 leaf stages of rice had an excellent weed control efficacy with above 90% up to 30 DAS without a phytotoxicity of rice plant and the control efficacy of over 80% was maintained until 60 DAS. However, these two herbicides controlled Echinochloa crus-galli very effectively above 97% but Aneilema keisak and Aeschynomene indica were not controlled by cyhalofop/bentazon ME and Cyperus serotinus by pyribenzoxim EC. Therefore, to control those problem weeds, second systematic application of pyribenzoxim EC and pyrazosulfuron/mefenacet G for A. keisak and A. indica, and pyrazosulfuron/molinate G, cyhalofap/ azimsulfuron/molinate G, pyrazosulfuron/mefenacet G and bentazon SL for C. serotinus at 30 DAS was found to be very efficient herbicide systems.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.184-191
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• 1989

The effect of various supplementary light sources on the agronomic characteristics has been investigeted for generation acceleration of barley in green house with the condition of 15$^{\circ}C$ and 8 hrs. day light followed by each supplementary light sources including incandescent electric lamp (IN), Blue fluorescent lamp(BF). day-light fluorescent lamp(DF), Biolux lamp(BL), BL+BF, In+BF and IN+BL. Leaf number of main stem, leaf area, culm length, dry matter yield of shoot, number of grain per spike, grain yield per plant were most sharply decreased with the exposition of IN, while flag-leaf emergence on main stem and I, 000 grain weight were earlist and heavist respectively with the exposition of IN. In appeared to be best light source for shortening the days to heading, but IN + BF will be most desirable light source with considering both days to heading and adequate yield at the same time.

• Korean Journal of Plant Resources
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• v.21 no.2
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• pp.134-138
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• 2008

Nerine from south africa and its sparkling flower shape make us estimate it as a hopeful kind of cut follow. There was a few studies on Nerine in korea. We started this study to set bulb propagation methods. The propagation by tissue culture was changeable according to the growth regulators The best growth regulator combination which makes a lot of Bulblet was NAA $0{\sim}0.5$ + BA $0.5{\sim}2.0mg\;{\cdot}\;L^{-1}$ in Nerine bowdenii ‘Favourite’ and Nerine sarniens ‘Red’ respectively. The adjust culture media source for tissue culture were glucose 9% as a carbon source and ($NH_4+NO_3$) 40mM as a nitrogen source. When glucose was used as a carbon source, Bulblet were harvested a little bit low then sucrose but comparative emergence rate was so high that it is good for carbon source in nerine tissue culture. When we consist culture media as MS+BA $1.0mg\;{\cdot}\;L^{-1}$+sucose 7% + ($NH_4+NO_3$) 40mM, the produced Bulblet were reached up to 1.7 each per bulb and emergence rate was up to 100% irrespective of acclimatization period. The suitable culture explant for nerine tissue culture was scale. When scale was cultured with MS+BA $1.0mg\;{\cdot}\;L^{-1}$+sucose 7%, its propagation efficiency was 54 times greater than using growing point. A proper culture part of the scaly leaf was middle part (8 scaly leaf from outer 8th scaly leaf) when middle part was cultured the number of Bulblet were up to 1.8 each per explant.

• Korean journal of applied entomology
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• v.4
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• pp.39-46
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• 1965

The author studied on the bionomics of Oriental moth. Cnidocampa flavescens WALKER, damaging to the persimmon tree n the southern part of Korea from 1964 to 1965. The results can be summarized as follows; 1. Emergence peak period of Oriental moth was mid-June in Taegu district and eggs are deposited on the opposite side of persimmon tree leaf. Specially most of eggs are deposited on the terminal part of opposite side and peak period s also mid-June. 2. Hatched Percentage of eggs was $84.4\%$ in 1964 while $96.1\%$ in 1965 at the rearing room. Mean egg Period was $5.984\pm0.162$ in 1964 while $6.262\pm0.094$ days in 1965. Thus during two years, the egg period was about 6 days. 3. In the growth ratio of Oriental moth fed on various host plants persimmon tree, Acer negund, Hazel-wood and Platanus, the best growth ratio was shown on the leaf of Hazel-wood from 1st till 3rd instar, but, on the contrary, persimmon tree was the best from 4th till the last instar. The growth ratio of head width was also the same tendency as the body length above mentioned. Individuals fed on the leaf of platanus were dead after 20 days. 4. Oriental moth has one generation a year and molts 6 times. The first molting occurred in 5 hours after hatched, and the other moltings were done at f days intervals. After 3 days since the last molting, larvae made the non for over-winter in it. 5. As the bristles on the process of larval body are different from each position and instar, judgement of instars are possible by the counting of bristles on the body according to the Table 8. Specially the bristle of L. 2., D. 2, 3 ,8. 10. and L. 1, 3, 4, 5, 6, 7, are perfectly different from each instar. From these bristles, instars can be recognized easily. 6. Pupation of larvae in the over-wintered cocoon on the stem of persimmon tree was done in mid-May and continued will early June when emergence will take place. 7. Mean number of eggs in the ovary was $1325.5\pm2.7182$

• Korean Journal of Weed Science
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• v.10 no.2
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• pp.83-92
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• 1990

Experiment was conducted to establish the weed control system on the paddy fields by investigating species, period and amount of weeds in Gangwon province. Four locations were selected for these experiments : West plain area, Chunchon(74m above the sea level), mid-mountainous area, Hongchon(300 m), high alpine area, Hoengsong(450m), and east sea area, Myungju(14m). Weed emergence was investigated 6 times from 10 days after transplanting to 60 days with 10 days interval. From the experiments stated above, the results were summarized as follows ; The identity of weed species was small in grass family, but broad-leaf family was numerous. Also the dominant weed species was generally the perenial weeds. The weed emergence was initiated from 10 days after translanting. The amounts of weed counted the most in Chunchon. A large number of weeds were emerged between 30-60 days after transplanting in Chunchon and between 40-60 days after transplanting in Hongchon and Hoengsong. Among agronomic characteristics affected by weed emergence during rice development, plant height was decreased by 2~4cm, panicle number by 1.3~2.9, spikelet by 3.7~7.5, ripening rates 3.3~6.5%, and milled yield by 12~17%, respectively.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.201-212
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• 2007

This study was conducted to investigate the biology of three species, Tipula latemarginata Alexander, T. nova Walker and T. aino Alexander, of the Genus Tipula in Korea. Field surveys for the biology of the species were carried out at the three sites of Neaseong Stream area in Bongwha County from January 2001 to December 2005. Also many individuals of the species were reared in laboratory to investigate the biology. The larval habitats of the species were streams, rivers, paddy fields, damp earth or leaky revetments. The Tipula larvae were herbivorous. Newly-hatched first instar larvae fed on soft algae, and the larvae gradually fed on leaves, stems and roots of a variety of plants or hard leaf litters, as they grew. During the molting of the larvae their body kept moving from left to right and up and down. Molting usually took not more than 2 hours, and about four hours after molting, the larvae started to eat heavily. The Tipula larvae in aquatic places moved to drier land for pupation and went through short prepupal stage lasting 1-2 days for pupation at fourth instar larval stage. When emerging, the Tipula pupae placed their head and thorax on the earth, but the other parts in the earth. Emergence from the pupal case required about 20 min. to one hour. Mating of Tipula adults took place within 5-7min. after emergence and the duration of mating was about 40 min. The female adults of the species laid eggs by walking with 3 pairs of legs over the damp earth or algal beds. Their body was positioned vertically on the ground with their wings spread $120^{\circ}$ and legs landed on the surface. The oviposition usually took place from one day to 4 days after emergence and the number of eggs carried by female adults were an average of 501-760 per individual. Tipula adults didn't normally feed, and drank water only occasionally. For a few days after emergence, the adults reared in the laboratory rarely drank water. As they neared to death, however, they frequently drank water. The longevity of adults reared in the laboratory with only water during the summer was ca. 4-9 days and males usually survived a little longer than females. The longevity of T. nova was increased 3 times or more as much by feeding them 3% sugar water. Male adults of T. latemarginata outnumbered female adults by 2.6 : 1 in the fields.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.327-333
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• 2009

Biological Characteristic of Obolodiplosis robiniae and insecticidal activity of some insecticides against larvae of O. robiniae were investigated. Egg was in oval shape, and its color was light orange and became red when close to hatch. Length of the major axis and the minor axis of egg was 0.4 mm and 0.1 mm, respectively. Larval color was milky and size was 2.6 mm. Pupa was deep brown and its size was about 3.2 mm. Wing and abdomen of adult was black and reddish, respectively. Size of female adult was about 3.3 mm, and larger than male adult. Number of eggs in the ovary was $192.3{\pm}50.7$. First emergence was from late April to late May, and second from late May to late June. Third emergence was from late June to late July. Newly emerged adult escaped from soil, and second and third emerged adult escaped directly from gall of Robinia pseudoacacia leaf. Egg parasitoid was identified as Platygaster robiniae and parasite rate was 51.6%. Among test insecticides, imidacloprid 10% WP and thiacoprid 10% FL showed very strong insecticidal activity against larvae of O. robiniae at 48h later after treatment.

• Korean Journal of Agricultural Science
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• v.30 no.1
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• pp.11-19
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• 2003

The life-cycle of the aphid-parasite, Aphidius gifuensis, took 11.9 days at $25^{\circ}C$ and 12.1 days at $30^{\circ}C$. The female appearance rate of A. gifuensis was the best at $20{\sim}25^{\circ}C$ compared to the other temperatures. Optimum rearing temperature of Aphidius gifuensis was $20{\sim}25^{\circ}C$ Optimum temperatures for A. gifuensis emergence were $20^{\circ}C$ and $25^{\circ}C$ with 99.1% and 98.2%, respectively. However the emergence rate of Aphidius gifuensis was 58.8% at $10^{\circ}C$. There was a positive correlation between A. gifuensis adult activity and temperature, but there was a negative correlation between developmental period of Myzus persicae nymph and temperature. Among the pests occurring in pepper greenhouse, dominant species was M. persicae and its density was 6~1,024 per plant. The damaged fruit rate by Helicoverpa assulta was 3.3~53.3%. The number of aphid and mummy in the A. gifuensis released plot were 173.5 and 10 in June, 1.8 and 17 in July, 2000, respectively. The numbers of Aphidius gifuensis were 7.5 and 0.4 in May, 27.1 and 2.1 in June, 2001, respectively. The suppressive effects on M. persicae in A. gifuensis released plot was better than the control plot, but there was no significant difference compared to the pesticide-sprayed plot. The first leaf length and the stem width in the A. gifuensis released plot, the control plot, and the pesticide-sprayed plot were not significantly different, but the A. gifuensis released plot showed the highest yield among the plots.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.373-377
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• 1997

The bird repellent, methiocarb 50% WP, has been used to reduce the bird damage in the crop field in the European countries. The bird damage occaisonally would occur in the wet direct seeded rice and in soybean field, and resulted in decreasing the crop productivity by the reduction of seedling emergence rate. In this experiment, rice seeds, Hwasungbyeo(Oryza sativa), were coated with the different application rate of methiocarb, 5, 10 and 15 per kg seed, and soybean, Taegwangkong(Glycine max), 2.5, 5.0 and 7.5g. In rice, the seeds coated with 10 and 15g of methiocarb were not lost by bird, while those with 5g and control were lost to 37 and 50% of total seeds, respectively. No damage by birds was observed in rice seedling when the coleoptile and radicle of rice were emerged at 7 days after the water seeding. The crop injury of methiocarb reducing the emergence rate of seedlings, shortening the shoot length, and decreasing the leaf number was occurred at the treated of methiocarb 15g per kg seed. In soybean, the loss of the sprouting by birds was lower in the treatment of methiocarb 7.5g per kg seed than that in both the control and the treatments of methiocarb, 2.5 and 5.0g per kg seed. No crop injury by the treatment of methiocarb was observed in all application rate.