• Korean Journal of Weed Science
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• v.10 no.2
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• pp.103-108
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• 1990

Germination test, nutrient culture test and pot experiment were conducted to determine selectivity of naproanilide between rice plants and paddy weeds. Naproanilide more severely inhibited growth of Scirpus juncoides, Sagittaria pygmaea and Cyerus serotinus than that of rice plant and Echinochloa crus-galli at germination stage. Root growth was severely inhibited than that of shoot growth by naproanilide treatment. Naproanilide severely inhibited rice plant and Echinochloa crus-galli at 30 uM, Sagittaria pygmaea at 1 uM and Cyperus serotinus at 10 uM in nutrient culture test, Rice plant and Echinochloa crus-galli did not show the difference of tillers and dry weight, but Scirpus juncoides, Morzochoria vaginalis and Aneilema keisak were severely inhibited at 15g/a and Sagittaria pygmaea and Cyperus serotinus at 30g/a in pot trial.

• Korean Journal of Plant Resources
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• v.12 no.4
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• pp.282-288
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• 1999

The experiment was carried out to determine the effects of soil condition on the agronomic characters and aromatic substances in cultivated Codonopsis Lanceolata. An increase of planting densities of Codonopsis Lanceolata. from 1 to 5 plant per pot resulted in the smaller root width, but root yield increased from 109.8g to 286.9g per 1/200pot. The width growth as soil water contents were higher in surplus soil water than that of cultivated deficit soil water. The contents of water, reducing sugar, crude protein and malic acid were higher in cultivated wild than in cultivated upland soil. The higher contents of volatile essential oils as 3-rnethylpentanoic acid and squalene was obtained at the normal soil moisture.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.27-41
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• 1968

In order to clarify the effect of various forms or phosphate on the production of paddy in Korea and to find out the superiority of any form, a number of field and pot experiments involving various phosphate fertilizers were carried out in addition to conducting one each of sand culture and soil culture pot experiments in 1963 and 1964. The results of these studies are summarized as follows: 1. In sand culture experiment, the best effect of a phosphate fertilizer was obtained with the mono-calcium phosphate which is soluble in water, followed by citric acid soluble phosphate such as fused phosphate and di-calicum phosphate. However, in the pot culture and field experiments, fused phosphate had shown it's superiority than triple superphosphate which contains water soluble form of phosphate followed by hypo phosphate, roasted phosphate, compound fertilizer, and slag phosphate. The effect of rock phosphate was the least in most cases. 2. The superiority of fused phosphate to triple super phosphate in soil culture was supposed to be: a) The fused phosphate can neutralize the soil acidity. b) The fused phosphate can supply magnesium and magnesium lead to the balanced conditions of exchangeable bases in soils. c) The magnesium in the fused phosphate helps the transportation of phosphate, and regulate the absorption of the element.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.228-233
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• 1989

Successive changes of transpiration by the tobacco plant during the growing season with pot trial treated with 30cm and 100cm ground water tables were compared with change of soil moisture content in rhizospere of field under natural rainfall conditions. Transpiration from the 41st to the 60th day after transplanting was the highest showing about 50% of total transpiration of whole cultivation period. As the result, soil moisture condition in rhizospere of field was kept insufficiently during the above period. Transpiration by the plant was so remarkably affected by the meteorological environment that the transpiration on rain-cloudy day was one third of that on clear day at middle stage of the growth. Maximum transpiration in a clear day was obtained from 14:00 to 16:00 at the 58th day after transplanting.

• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.520-530
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• 2011

This study was carried out to evaluate the possibility of rice double cropping in Korea by assessing the growth and yield performance of rice cultivars transplanted at the extremely-early date. When the transplanted rice seedling was exposed to low temperature below 0℃, the survival rate decreased drastically. However, short exposure to below 0℃ one or two times did not damage transplanted rice seedling so severely. Thus, the earliest transplanting in spring would be possible when minimum temperature rises above 0℃. Compared with the conventional seedling nursery tray (CSNT), seedling rearing with the potted nursery tray was more effective for increasing leaf age and seedling dry weight during nursery period. In the first rice cropping, rice cultivation with seedlings reared in PSNT showed shorter growth duration and cumulative temperature from transplanting to heading than that with seedlings reared in CSNT. The earliest heading date on July 4 in Jinbuolbyeo was earlier by two to three days than that of Dunaebyeo. If rice has not exposed to cold damage, the earliest heading date of Jinbujolbyeo can advance to June 30 or July 1. In this case, rice harvest would be possible on August 5, enabling the rice transplanting of the second rice cropping before August 10. At transplanting time with low temperature damage rice yield were less than 400 kg/10a while rice yield exceeded 400 kg/10a at transplanting time without low temperature damage.

• Korean Journal Plant Pathology
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• v.12 no.3
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• pp.331-335
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• 1996

1993년 전북완주와 충남 서산 지역에서 생강 근경 부패병에 감염된 식물체로부터 Pythium sp.를 분리하였으며, 52균주를 형태적 특징과 병원성 검정을 통해 Pythium zingiberum으로 동정하였다. P. zingiberum으로 동정된 균주들이 재배지에서 사용되는 metalaxyl(MT), metalaxyl+copper oxychloride(MC), echlomezol(EM) 및 propamocarb hydrochloride(PC)등에 균사 생장, 난포자 형성에 미치는 영향 및 약제방제 효과 등을 검토하였다. MT, MC, EM 등이 혼합된 평판배지에서의 균사생육 정도는 50, 100 mg/L에서도 균사생장 억제를 나타냈으나 3균주는 EM 100mg/L에서도 균사생장이 저지되지 않았다. 100mg/L에서도 균사생육 억제효과가 적은 PC의 경우 저항성균주의 난포자 형성량은 약제 희석농도가 높아질수록 저하되었으나, 감수성을 나타낸 균주는 10, 50mg/L에서 오히려 증가하였다. 또한 폿트실험을 통한 약효검정 결과에서도 MT, MC, EM등은 대조구에 비해 생강 근경부패병을 억제하였다.

• Journal of Plant Biotechnology
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• v.49 no.3
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• pp.222-229
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• 2022

Apples are the most grown fruit crops in the fruit industry of Korea. However, virus or viroid infection such as apple mosaic virus (ApMV), apple stem grooving capillovirus (ASGV), apple stem pitting virus (ASPV), apple chlorotic leaf spot virus (ACLSV), apple scar skin viroid (ASSVd) causes fruit yield reduction and poor fruit quality. Therefore, in this study, we examined to established an efficient virus-free system to eliminate the most infected ASGV virus in domestic apple orchard. We investigated that the shoot growth rate and the virus removal rate in ASGV infected potted apples that were treated with heat treatment in a growth chamber (constant temperature/humidity device) maintained at 36℃, 38℃ and 40℃ for 4 weeks. Here we found that the shoot growth rate was the highest in the heat treatment group (36℃) and the virus was removed in the middle and top of the shoot but not in the bottom. The virus was did not removed in the 38℃ and 40℃ heat treatment group in all section of shoots, and the heat treatment group (40℃) died after 4 weeks of heat treatment without growth of shoots. We performed in vivo shoot-tip grafting using the shoot-tip of potted apple heat-treated at 36 ℃, and we also investigated the viability and virus removal rate, which showed 94% viability and 20% virus removal rate. Collectively, our results suggest that it would be possible to produce the virus-free apple plants through heat treatment and shoot-tip grafting.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.3
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• pp.273-281
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• 1990

Two rice varieties, Samkangbyeo and Sangpungbyeo, were transplanted on 1/2000a pots at 6 different dates beginning on May 11 with 10 day interval in 1987 and at 4 different dates beginning on May 21 with 10 day interval in a paddy field at the Chungbuk Provincial Rural Development Administration. Dry matter distributions to stem and leaf sheath, leaves and ear at different growth stages were analyzed to provide basic informations neccessary for the development of dynamic growth model. Dry matter production was reduced as transplanting was delayed and the degree of reduction was greater at the transplanting later than June 1. Dry matter distribution to stem and leaf sheath was increased up to 60-70 days after transplanting with the maximum ratio between 60-70%, which were decreased to 37-43% in pots and 27-33% in field at the end of ripening stage. On the other hand, dry matter distribution to leaf blade was decreased from 40-50% at transplanting to 11-17% at harvesting. Ear dry matter distribution increased rapidly after heading and the distribution ratio was 42-49% in pots and 52-62% in field. Although regression equations to predict dry matter distribution to different parts of rice plant were satisfactory for individual experiment, the application to different experiment was not appropriate.

• Korean journal of applied entomology
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• v.10 no.1
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• pp.31-38
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• 1971

Tolerance test in plastic vat, pot and fold tests were carried out to investigate the selective herbicides for soybean culture in sandy loam. The soybean plants showed great tolerance against herbicides such as Tri-allate (Avadex-BW), Alachlor (Lasso), Butachlor (Machete), Propachlor (Ramrod), Nitrofen (TOK), MO, HE-314, Nitrofen/Dinoseb(TOK/DNBP), and Chlo.oxu.on (Tenoran), and the growth was normal even when each was treated with the herbicides up to 2ft3 times of the recommended concentrations. Soybean plants showed a slight tolerance against Prometryne (Gesagard), Propazine (Gegamil), Diuron (Karmex), Metabromuron (Patoran), Linuron (Lorox) and Swep when each was treated with herbicides up to 1-2 times of the recommended concentrations. Great injury or withering was noticed due to the high sensitivity of soybean to Simazine (CAT) and to Floumetron (Cotoran). In pot and field experiments with herbicides such as Butachlor (Machete), Alachlor (Lasso), Nitrofen (TOK), Kerb, Nitrofen/Dinoseb (TOK/DNBP), Swep, Linuron (Lorox), Simazine (CAT) and PCP, the following results were obtained: Great injuries were noticed with Simazine (CAT). Also, Linuron (Lorox) and Kerb showed a slight injury at early growth stage of soybean, Nitrofen (TOK) , Nitrofen/Dinoseb (TOK/DNEP), Alachlo. (Lasso), Butachlo. (Machete) and Swep had high selectivities for soybean and no injury was noticed. With respect to herbicidal effects there was a greatly significant difference between treated plots and non-treated plots with the exception of Simaaine (CAT) plot in field test. E. crusgalli and C. sanguinalis were tolerant against Simazine(CAT) and Linuron(Lorox). Cyperus and E. annuus were tolerant against Kerb. Great herbicidal effects on grasses were observed in Alachlor (Lasso) and Butachlor (Machete) plots. Among broad-leaf weeds, P. hydropiper and C. album were tolerant against Butachlor (Machete) and Alachlor (Lasso). When soybean was treated with the herbicides such as Alachlor (Lasso) (ai. 150g/10a), Butachlor (Machete) (ai. 300g/10a), Nitrofen (TOK) (ai. 250g/10a), Linuron (Lorox) (ai. 75g/10a) once after seeding, no additional wording was required till harvest.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.535-539
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• 2001

To establish the cultural practices of persimmon in heated plastic house, the growth and flower bud differentiation of 4-year old 'Nishimurawase' persimmon tree planted in 80 L pots were investigated. Temperature was kept at above $18^{\circ}C$. The earlier heating induced the earlier flower bud differentiation, while the number of days from bud burst to flower bud differentiation was 70-75 days, which was not affected by the date of heating. The date of flower bud differentiation in 'Nishimurawase' persimmon was May 1, May 21, and June 1 in the plastic house heated from Jan. 15, Feb. 15, and Mar. 15, respectively. The number of flower primordia per bud in the plastic house was 6.2-7.1, slightly fewer than that of 7.8 in the open-field, with the tendency of increasing the number by earlier heating. The days required for the differentiation of the last flower bud primordia from the beginning of differentiation of the first bud were 40-60, and that required for the flower bud differentiation of all buds on the same shoot was 30. The total carbohydrates in shoot increased and the contents of nitrogen decreased, resulting in increased C/N ratio just before flower bud differentiation, and it coincided with the time when the total carbohydates increased above 15%. During two weeks before flower bud differentiaton, The contents of zeatin per 1 g dry matter of shoot drastically increased from $27.2{\mu}g$ to $47.3{\mu}g$, while that of IAA slightly decreased from $188.6{\mu}g$ to $172.4{\mu}g$, and that of GA decreased from $2,225{\mu}g$ to $1,555{\mu}g$.