• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.4
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• pp.439-442
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• 2013

This study was conducted to develop the testing method for excessive water tolerance at germinating stage and to screen 31 domestic peanut cultivars. Regardless of peanut grain scales, the amount of seed absorption nearly reached the peak in 10 hours after imbibition. When peanut seed in vermiculate soil was directly soaked in water, ability of emergence did not reduced until 16 days and then sharply reduce to 25 days with non-emergence. When seeds germinated for 1, 2, 3, and 4 days after seeding (DAS) were soaked, the emergence abilities were distinctively varied according to the sequent soaking days such as 1, 2, 3, 4, and 5 days. This explained the negative relationship between first germinating days (DAS) and following soaking days. Using the method of 2 day germinating and 3 day soaking that show less than 70% of emergence ability, 31 peanut cultivars were applied to test excessive water tolerance. Emergence rates varied 0% to 69% according to cultivar. Cultivar Daekwang, Sinkwang, Daecheong and Baekseon had over 50% emergence rates. These results suggested that the degree of water resistance in germinating stage may be important point to evaluate the excessive water resistance among cultivars.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.427-434
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• 2014

This study aimed to investigate the effects of pre-harvest sprouting (PHS)-damaged grains of rice on seed viability, germination percentage and seedling emergence rate. As comparing the seed lots of same cultivar 'Hopum' with different PHS percentages, seed lot with 8% PHS (high PHS percentage) showed 30% lower germination than that with 1% PHS (low PHS percentage). The difference of seedling emergence rate and seed viability percentages between the two seed lots was consistent with that of germination percentage. PHS-damaged brown rice was observed protruded embryo, discolored endosperm and fungi infected grains. PHS grains were classified into two groups, PHS-I showing endosperm discoloration in one third of a grain and PHS-II in more than half of a grain. The seed lot with high PHS percentage had much more PHS-II grains than that of low PHS percentage. PHS-II grains showed remarkably lower germination percentage than PHS-I grains and got severely moldy during germination test. In laboratory experiment, morphological changes and re-germination ability of seeds which dried after germination by soaking were tested. Sprouted seeds of 3mm shoot length showed half discolored endosperm and had a strong resemblance with PHS-II grains. Re-germination percentage of 3mm sprouted seeds sharply decreased than 2 mm sprouted seeds. Sprouted seeds which were treated for accelerated-aging (AA) for 24hr at $45^{\circ}C$ were significantly reduced in re-germination percentage compared to that of non-AA-treated sprouted seeds. These results indicate that PHS with over 3mm shoot length can severely damage not only grain appearance but also seed viability, germination percentage and seedling emergence rate. Therefore, we conclude that larger difference of germination percentage or seedling emergence rate between seed lots having smaller difference of PHS percentage might be caused by accelerated seed deterioration in PHS-damaged rice grains.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.156-160
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• 2020

Emergence and early growth changes of stratification condition of tea (Camellia sinensis) seeds were investigated in 7 treatments (control, pH 4, pH 10, 70% ethanol (EtOH), 10 mM H₂O₂, 100 mM H₂O₂, and physical shock (5.9 J)). Ethanol treatment was toxic and did not induce emergence. The emergence rate was 36.7% in the control, 26.7% under pH 10, 46.7% under pH 4, 48.3% under physical shock, 51.7% under 10 mM H₂O₂, and 65.0% under 100 mM H₂O₂ treatments. It was higher by approximately 178% in the H₂O₂ treatment as compared to the control. Plant height was 6.5 cm in the control, 6.6 cm under pH 10, 7.6 cm under pH 4, 7.8 cm under physical shock, 8.3 cm under 10 mM H₂O₂, and 9.1 cm under 100 mM H₂O₂ treatments. Leaf length and leaf width were also higher under the H₂O₂ treatment. Therefore, hydrogen peroxide treatment induced emergence and increased the uniformity of early growth.

• Korean Journal of Weed Science
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• v.6 no.1
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• pp.85-96
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• 1986

From the two differently located orchards (even-site with adult tree and slope-site with young tree), weed emergence and the effect of various orchard herbicides on them were comparatively experimented. Weed emergence was assessed in emergence frequency, biomass, relative frequency, and herbicide responses were checked with the variarions in the above weed emergence characters and the weeding values. Herbicides applied were paraquat, glyphosate, oxyfluorfen, napropamide and ustinex using the recommended rates, respectively. Weeds emerged were 7 life-forms, 23 families and 45 species. Among other families, weeds Umbelliferae, Commelinaceae, Gramineae and Polygonaceae couldn't classified in any similarly correlated cluster. However, according to "1-Q mode cluster analysis" of each herbicide performances, "paraquat or glyphosate" with "napropamide or oxyfluorfen" were selected as the most unrelated herbicide pairs expecting the best combination value in mixture model, respectively.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.307-313
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• 2003

Japanese pine sawyer, Monochamus alternatus, is a primary vector of pinewood nematode, Bursaphelenchus xylophilus in Korea. Emergence characteristics of the adults were studied in Jinju, Korea using dead pine logs in which the larvae of the sawyer overwintered from 1999 to 2002. Emergence data showed that the adults began to emerge out of the logs in sunny place from May the 15th in average of the four years. Cumulative emergence ratio (CER) reached at 50% at mid-June, and the emergence terminated by early or late July depending on years. In shady place, however,50% CER was reached 17 days later than in sunny place. The 50％ CER of males reached 1 to 4 days earlier than that of females depending on years. Of the adults emerged from the logs collected from February to April in 2001, 97.6％ was univoltine, and the rest was biennial which emerged from May to July of the next year. Female and male adults emerged throughout 24 hours; 32.3% of the total adults emerged from 8 to 12 a.m. It took 68.0 seconds for the adults to escape from pine logs.

• Korean Journal of Weed Science
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• v.10 no.3
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• pp.186-191
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• 1990

This experiments was conducted to investigate the dormancy of Eleocharis kuroguwai tuber in the earth and the influence of seeding time and depth on the emergence of Eleocharis kuroguwai. The tuber of Eleocharis kuroguwai on underground was formed the most amount between 10cm and 15cm layer and formed the second a lot of tuber in the soil layer between 5cm and 10cm, the third between the surface of the earth and 5cm, the least between 15cm and 20cm. The total mean emergence of tuber was 78%, and the dormant tuber was approximately 22% of total tuber formed during a year in the earth. The distribution of dormant tuber under the ground was about 42% between 15cm and 20cm, 39% between 10 cm and 15cm, 14% between 5cm and 10cm, and 5% between the surface of the earth and 5cm. The dormancy percent of tuber formed at each soil layer was about 60% between 15cm and 20cm, 21% between 10cm and 15cm, 12% between 5cm and 10cm, and 7% between the surface of the earth and 5cm. The emergence days of the tuber seeded at low layer was short, and the emergence rate was high, The tuber was formed much more on seeding at May 30th than June 30th.

• Korean Journal of Medicinal Crop Science
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• v.9 no.1
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• pp.68-75
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• 2001

Reasonable seedling emergence is a prerequisite for successful crop cultivation especially in medicinal crops. The study was carried out to model the pretreatment or seed treatment of Codonopsis lanceolata seeds by evaluating the treatment effects of priming, $GA_3$, drying and water imbibition after drying on their germination and then their successive seed treatment on the basis of its seedling emergence. The priming using $Ca(NO_3)_2$ and $GA_3$ treatment under their different concentrations and light quality illuminated for 12 hours a day were separately done and the two best results from priming and $GA_3$ treatments were compared to determine the better one. The drying of imbibed seeds using the above best result and water imbibition of the dried seeds were successively done to measure the rates of germination and emergence. On the greatest germination rate of the first two individual treatments, priming was obtained at $Ca(NO_3)_2$ 150 mM under blue, red light or darkness for 2 days but $GA_3$ was done at 0.1 mM under blue light imposed for 3 days. However, the result of the latter $GA_3$ treatment was better than that of priming. $GA_3$ treated seeds were best desiccated under $35^{\circ}C$ and 4 hour red light illumination. A day water imbibition immediately before sowing increased the germination rate of seeds dried after $GA_3$ treatment. Seedling emergence tested after all 3 successive treatments, $GA_3$, drying and water imbibition before sowing was greater than the two others, only $GA_3$ treatment and the combination of $GA_3$ and drying, meaning that its pretreatment of seeds or seed treatment must follow the successive procedure of the above 3 ones.

• Korean Journal of Medicinal Crop Science
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• v.10 no.2
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• pp.75-81
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• 2002

Indoor seed treatments to elevate seedling emergence should be of value. The study was done to model the presown treatments of Platycodon grandiflorum seeds by evaluating the treatment effects of priming,$GA_3$, drying and water imbibition after drying on their germination and then their successive seed treatments on the basis of its seedling emergence. after priming using $Ca(NO_3)_2\;and\;GA_3$ treatment under their different concentrations and light quality illuminated for 12 hours a day were done separately and their two best results were compared to determine the better one, drying of imbibed seeds using the above best result and water imbibition of the dried seeds were successively done to check the rates of germination and emergence. In each treatment of priming and $GA_3$, the former best germination occurred at $Ca(NO_3)_2$ 150 mM done under 2 day darkness but the latter one did at 0.01 mM done under 12 hour a day red light forced for 3 days. Of the two best results from priming and $GA_3$ treatments, the latter result was shown higher germination rate. $GA_3$ treated seeds were best desiccated under $35^{\circ}C$ and 4 hour red light illumination. The germination rate of seeds dried after $GA_3$ treatment was enhanced as imibibed 2 days immediately before sowing. Seedling emergence of all 3 successive treatments, $GA_3$, drying and water imbibition before sowing was the greatest than the two others, only $GA_3$ treatment and the combination of $GA_3$ and drying, in which indicated that its presown seed treatment must follow the successive procedure of the above 3 ones.

• Korean Journal of Weed Science
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• v.30 no.2
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• pp.143-152
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• 2010

Herbicidal characterisitcs of natural product chrysophanic acid were investigated in a greenhouse condition. At early- and middle-stage post-emergence treatments, several grasses and broadleaf weeds appeared to be very susceptible to chrysophanic acid. However, any significant herbicidal activity treated by pre-emergence did not occur at concentration ranges from 31.3 to 1,000 ug $mL^{-1}$. Herbicidal activity of chrysophanic acid estimated by visual injury for large crabgrass was much higher when applied at 7 to 14 days after seeding than at 21 and 28 days after seeding. By post-emergence treatment, chrysophanic acid caused very considerable phytotoxicity on several grasses and broadleaf crops. In herbicidal interaction experiments determined by Colby's method, the effect of chrysophanic acid and caryophyllene oxide tank-mixture showed very high synergistic activity. Although chrysophanic acid did not give any pre-emergence effect, herbicidal spectrum tended to be very wide and strong when treated by post-emergence. These results suggest that chrysophanic acid possesses a possible potential to develop as a natural herbicide.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.204-213
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• 1986

The objective of this paper was to examine the response of rice seedling emergence and early growth under the different temperature (day/night, 29/21$^{\circ}C$, 17/17$^{\circ}C$, 12/12$^{\circ}C$) and the different seeding depth (1 cm, 2 cm, 3 cm). The trial was carried out in the phytotron and field in the Crop Experiment Station, Suwon, Korea in 1985. Calcium peroxide-coated seeds were very effctive in promoting seedling emergence, seedling establishment and eary growth of rice. Coated seeds were more effective in low temperature condition (17/17$^{\circ}C$, 12/12$^{\circ}C$) than in high temperature (29/21$^{\circ}C$) at the phytotron trial. The deeper the seeding depth, the less the emergence and seedling establishment, and the available seeding depth was I cm in the direct seeding under the flooded soil. In the field trial (seeding date, May 1) the results for the emergence and seedling establishment were similar to those in the phytotron trial. Available cultivars for the direct seeding cultivation under the flooded soil were Cheonmabyeo, Namyangbyeo, Kihobyeo, Akibare, Nakdongbyeo and Dongjinbyeo in Japonica type, and Taebaegbyeo, Samgangbyeo and Gayabyeo in Indica x Jponica type. Coefficients of variation to the emergence and seedling establishment between rice cultivars were very high. Therefore, in the direct seeding cultivation under the submerged paddy, choice of rice cultivars and improved technique for direct seeding will be more necessary.