• Applied Biological Chemistry
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• v.34 no.2
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• pp.168-173
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• 1991

The uptake of $Mn^{+2}$, a metal cofactor Mn-SOD, by rice seedings resulted in not only a substantial increase in SOD activity in leaf tissues of the plants, but also a significant enhancement of their cold tolerance : the relative extent of the cold tolerance appeared to accord with relative level of the SOD activity. In contrast, $Fe^{+3},\;Cu^{+2}$ and $Zn^{+2}$, which are the cofactors of Fe-SOD and Cu/Zn-SOD, were found to be ineffective for increasing the SOD activity as well as for improving the chilling-resistant capacity of the plants. The results suggest that Mn-SOD, which is most likely induced by its substrate(superoxide) and activated by the presence of $Mn^{+2}$a at high level, is the enzyme acting as an active component of the defense system against low temperature stress in rice plants. In addition, the application of abscisic acid which has been know to protect to some extent certain plants from chilling injury brought about an increase in SOD activity in rice tissues, providing another affirmative information for the crucial role of SOD under the circumstance of cold stress in plants.

• The Korean Journal of Mycology
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• v.16 no.3
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• pp.151-156
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• 1988

A leaf anthracnose disease of pepper(Capsicum annuum L.) seedling caused by Colletotrichum coccodes was found in fields of Chungnam District for the first time in 1988. Initial symptom of the disease was spotting on leaves and stems of the seedlings. The spots became sunken and gradually increased in size and coalesced to form bigger irregular spots and blights on the leaves. In severely affected fields, many pepper seedlings were defoliated and lodged. Field survey revealed that the infection rate of anthracnose ranged form 15.3% to 92.3%. Conidia from lesions on seedlings were hyaline, aseptate, straight, cylindrical with obtuse ends, $115-25(av.\;19.\;5){\times}2.5-4.8{\mu}m(av.\;3.3{\mu}m)$ and setaes were straightly extended above the acervuli, $41.3-136.3\;{\um}m(av.\;85.0{\mu}m)$ long. The fungus produced abundant sclerotia on PDA when it was cultured under darkness. In the inoculation experiments, the fungus was found to infect pepper seedlings and fruits, and fruits of tomato and egg plant.

• The Korean Journal of Mycology
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• v.44 no.3
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• pp.155-165
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• 2016

Domestic and international production of Tricholoma matsutake has decreased owing to matsutake forests being left alone, host plant disease, forest fires, climate change, and so on. In order to identify strains that are suitable for the production of T. matsutake-inoculated seedlings, Pinus densiflora seedlings were inoculated with T. matsutake after in vitro rooting and mycorrhization was examined in the roots of T. matsutake-inoculated seedlings after 6 months. The mycorrhization rate was greater than 80% for 5 strains (NIFoS 421, 434, 1681, 1984, and 2001) out of 19 total strains. Seven strains (NIFoS 434, 441, 561, 562, 1016, 1807, and 1812) showed shoot/root ratios of less than 3.0 and had a seedling shoot biomass of 2.0 to 4.8 times higher than that of the root. Eight strains (NIFoS 441, 561, 562, 1016, 1807, 1812, 1984, and 2001) stimulated increases in shoot volume and three stains (NIFoS 441, 562, and 1812) promoted the growth of root biomass by mycorrhizal formation. In conclusion, 4 strains (NIFoS 434, 561, 1984, and 2001) out of 19 total strains tested showed higher mycorrhization rates and seedling growth than those of the other strains. We expect that the use of these four strains may contribute to T. matsutake-inoculated seedling production.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.5
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• pp.311-322
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• 2003

Mycorrhizae is well known to increase the uptake of P and other mineral nutrients of plants. But if available P levels in soil is too low or high, mycorrhizae formation is limited. This study was carried out to determine the optimum level of available P for mycorrhizae formation of Poncirus trifoliata (trifoliate orange) seedling in volcanic ash soil. Eight levels of P in the range $0-1050mg\;kg^{-1}$ were applied with double superphosphate, and in each P level mycorrhizal fungi inoculated and uninnoculated treatments were included. The seedlings were grown in a greenhouse for 5 months and mycorrhizae formation, growth, and nutrient uptake were measured. As P application level increased, mycorrhizae formation increased at lower range of P application and the highest formation ratio of 43% was found at $100mg\;kg^{-1}$ P level ($2.6mg\;kg^{-1}$ available P in soil). At further higher levels of P application, mycorrhizae formation was rather suppressed. Seedling growth was increased by the inoculation of mycorrhizal fungi, and maximum growth was found at $100mg\;kg^{-1}$ P level where mycorrhizae formation was highest. The growth and mineral nutrient uptake of Poncirus trifoliata seedling represented a significant positive correlation with mycorrhizae formation at all P treatments.

• FLOWER RESEARCH JOURNAL
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• v.16 no.2
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• pp.134-142
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• 2008

This work aims to obtain basic information for seed propagation of Hydrangea serrata for. acuminata. The germination percentage of the seeds taken on 15 November, 30 December, and 23 January was $90.0{\pm}4.16%$, $84.4{\pm}5.52%$, and $88.9{\pm}2.40%$, respectively. This suggest that seeds of Hydrangea serrata for. acuminata are non-dormant seeds. The optimum temperature for germination was $25^{\circ}C$ and light was necessary. Most of the growth parameters (shoot and leaf length, stem diameter, root length, no. of roots, T/R ratio, and fresh and dry wts.) were significantly greater at $25/20^{\circ}C$ and $25^{\circ}C$ than at the other temperatures. Low T/R ratio at relatively cool temperatures (15 and $20^{\circ}C$) was caused by suppressed top growth. In light quality treatment, red light (RL) significantly enhanced stem elongation. The greatest photosynthetic pigments (total chl, chl a/b, and carotenoid) were observed in seedlings grown in blue light (BL), followed by seedlings grown in RL+BL. When blue light was added, higher pigment contents were found. Effect of plug cell size (50, 72, 128, 162 and 200 cells) on the growth of seedlings was investigated. The highest top growth was observed in seedlings grown in 50 cell trays, followed by seedlings grown in 72, 128, 162, and 200 cell trays. However, there was no significant differences between 162 and 200 cell trays. Especially, smaller size leaves were observed in seedlings grown in smaller cell trays (lower volume and high plant density).

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.34-34
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• 2019

털부처꽃(Lythrum salicaria L.)은 7~8월에 최산꽃차례로 붉은 자주색의 꽃이 피며, 밀원식물로 이용된다. 또한 예로부터 발효해서 술로 마시고 잎은 채소로 식용하였으며, 식중독 치료 및 설사를 멈추게 하는 효과가 있는 것으로 알려진 식물이다. 한국, 중국, 아프리카, 유럽, 북아메리카 등의 습한 지역에 분포한다. 본 연구는 다방면으로 이용이 가능한 털부처꽃을 관상용 소재로 개발하기 위한 최적의 유묘 재배 기술을 확립하기 위해 수행되었다. 유리온실 내에서 2019년 4월 27일에 종자를 파종하여 8주간 육묘하였다. 파종 용기는 162, 200 및 288 트레이로 달리하였으며, 토양 실험은 원예상토와 피트모스:펄라이트 3:1, 4:1 혼용토를 사용하였다. 파종립수 실험은 200구 트레이에 셀 당 1, 2, 4 및 6립으로 달리하였고, 추비는 hyponex (6.5-6-19)를 0, 250, 500, $1000mg{\cdot}L^{-1}$의 농도로 출아 후 2주 간격으로 총 3회 엽면시비하였다. 또한 차광 실험은 0, 55, 75%로 설정하였다. 대조구는 200구 트레이에 원예상토를 충진하고 셀당 1립씩 파종하여 무차광 조건에서 육묘하였으며, hyponex $500mg{\cdot}L^{-1}$를 추비하였다. 연구의 결과, 파종용기에 따른 털부처꽃 유묘는 셀 당 토양의 양이 가장 많은 162구 트레이에서 왕성하였다. 토양 종류별 실험은 원예상토 단용구에서 모든 생육이 양호한 결과를 보였으며, 피트모스와 펄라이트의 혼용토에서는 생육이 억제되었다. 파종립수에 따른 초장의 유의적인 생육 차이는 없었으나, 전반적인 생육은 1립 파종에서 우수하였다. 한편 2립 또는 4립을 파종구에서 비교적 생육이 양호하고 풍성하게 보이는 효과가 있어 관상적 이용에 적합할 것으로 생각되었다. 추비처리는 hyponex의 농도가 가장 높은 $1000mg{\cdot}L^{-1}$ 처리구에서 유묘의 생육이 가장 양호하였고, $500mg{\cdot}L^{-1}$ 처리에서는 무처리와 유의적인 차이가 없었다. 차광처리는 털부처꽃의 유묘 재배시 전반적인 생육을 증가시켰으며, 55% 차광에서 가장 우수하였다. 결론적으로 털부처꽃의 육묘는 162구 트레이에 원예상토를 충진한 다음 셀 당 2립 또는 4립을 파종하고 55% 차광 조건에서 재배하는 것이 효과적이며, 추비는 hyponex $1000mg{\cdot}L^{-1}$를 처리하는 것이 양묘 생산에 적합한 것으로 판단된다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.59-59
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• 2019

벼룩이울타리(Arenaria juncea M.Bieb.)는 7~8월에 백색의 꽃이 취산화서로 아름답게 피며, 산지, 산비탈 또는 메마른 초지에 자생한다. 청열 및 양혈의 효능이 있고, 은시호의 대용으로 쓰이며, 뿌리에는 triterpenoid saponins과 sapogenin이 함유되어 있다. 본 연구는 분화용 식물로 벼룩이울타리를 활용하기 위한 효율적인 포트 정식방법을 개발하기 위하여 수행되었다. 실험은 2018년 선행연구에서 생산된 유묘를 7월 2일에 정식하여 10월 15일까지 약 15주 동안 재배하였다. 대조구는 플라스틱 화분 10호($9{\times}9cm$)에 원예상토를 충진하고 200구 트레이에 셀 당 4립씩 파종하여 생산된 1셀을 정식하였다. 재배 실험은 용기종류[비닐포트(3, 4치), 플라스틱 포트(8, 10, 12호)], 토양 종류[원예상토, 중화 피트모스:펄라이트(3:1, 4:1), 마사토:중화 피트모스(2:1, 3:1)], 묘의 소질[파종 립수(1, 2, 4, 6립), 파종 용기(162, 200, 288구 트레이)] 등을 달리하여 진행하였다. 연구의 결과, 벼룩이울타리는 토양의 양이 많을수록 생육이 양호한 결과를 보여, 플라스틱 12호에 재배하는 것이 분화용으로 가장 효과적이었다. 한편, 비닐 4치와 플라스틱 10호의 경우, 플라스틱 12호와 생육에 큰 차이가 없어 경제적인 것으로 판단된다. 벼룩이울타리는 원예상토에서 재배하는 것이 전반적으로 생육이 우수하였으며, 다음으로 마사토와 피트모스 혼용토 순이었다. 그러나 피트모스와 펄라이트 혼용토는 비율과 관계없이 생육이 감소하며, 잎에 황백화 현상이 나타났다. 셀당 파종량을 달리하여 육묘한 후 정식한 결과, 전반적인 생육은 1립 파종묘에서 양호하였으나, 2, 4, 6립 파종묘가 1립 처리구에 비해 포트당 엽수가 약 1.35, 1.44, 2.01배 증가하는 경향을 보였다. 그러므로 유묘 생산시 셀당 파종량을 늘려 재배하는 것이 분화용으로 효과적일 것으로 판단된다. 파종용기별 유묘의 생육은 162, 200, 288구 트레이 순이었으나, 정식 후 약 15주 동안 재배한 결과, 162, 200구에서 생산된 유묘를 정식하는 것이 288구보다 양호하였다. 따라서, 육묘 단계에서 토양 및 공간을 절약할 수 있는 200구에 파종하여 재배하는 것이 효율적인 방법으로 생각된다. 결론적으로, 벼룩이울타리의 분화용 재배는 플라스틱포트 12호에 원예상토를 충진하고 200구 트레이에 4립 또는 6립을 파종하여 육묘한 묘를 정식하는 것이 가장 효과적이다. 한편, 경제적인 측면을 고려할 때, 재배면적을 적게 차지하는 비닐포트 4치 또는 플라스틱 포트 10호에 마사토와 중화 피트모스를 혼용하여 충진한 다음 유묘를 이식하는 것도 하나의 방법으로 판단된다.

• Journal of Bio-Environment Control
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• v.3 no.2
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• pp.119-127
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• 1994

This study was conducted to investigate the effects of temperature and light conditions on the vigor and growth responses of red pepper(Capsicum annuum L.) seedlings in the nonheated plastic houses with triple and quadruple coverings during winter. The results obtained were as follows ; 1. The growth in terms of plant height, number of leaves, leaf area and dry weight of each organ was reduced up to 50% in the triple coverings compared to quadruple ones. The greatest difference between the triple coverings and quadruple ones was the leaf area, showing two to five times larger in the quadruple ones. Therefore, the differences of the early environmental conditions during raising seedling stage was well reflected. 2. The leaf expansion in the early stage of seedling was delayed in the triple coverings and subsequently crop growth rate(CGR) significantly reduced. The specific leaf area (SLA) in the triple coverings was less than quadruple ones. The net assimilation rate (NAR) was increased in the early stage of seedlings and then reduced in the quadruple coverings. In triple ones, however, the great reduction showed at six weeks after sowing and then increased sharply. 3. The linear relationship among leaf area, total dry weight and leaf dry weight was observed in the all experimental areas, while between leaf area and crop growth rate only in the quadruple coverings, and between leaf area and net assimilation rate in both triple and quadruple ones. 4. The dry matter partitioned to the leaf increased up to six weeks after sowing in the triple coverings but reduced in the stem and root. However, the adverse results were obtained in the quadruple ones. 5. In the triple coverings, the number of branches showed the exponential increment while fruit weight showed linear increment in both triple and quadruple ones. Higher yield was obtained in the quadruple ones. 6. The shoot dry weight among the characteristics of seedlings was greatly contributed to the yield of red pepper after transplanting. Accordingly, one of the decisive criterion for good quality of red pepper seedlings was determined by the highest correlation between shoot dry weight of growing plant and fruit yield of pepper plant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.429-438
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• 2007

Early growth vigor(EGV) is one of the physiological characteristics that may contribute to the increase of genetic yield potential and radiation use efficiency by closing the canopy earlier. To estimate the genotypic variation of EGV, determine the relationships among the related traits, and identify the rapidly growing genotypes and indirect indicator for selection in breeding program, the evaluation of EGV and EGV-related traits was conducted for a total of 140 rice varieties consisting of 101 Korean, 25 Northern China and 14 IRRI-bred rice varieties in a serial sowing experiment in plastic rain shelter and plastic-covered nursery bed in 2003. EGV defined as the amount of leaf area and/or dry weight produced early in the season and the EGV-related traits such as length and breadth of the $2^{nd}\;and\;3^{rd}$ leaves showed highly significant positive correlation with the embryo and seed weight. Especially, the genotypic variation in the length of the third leaf was explained over 90% of genotypic variation in the seed weight. Owing to a large effect of seed size on EGV and its related traits, vigor measurements were adjusted based on their linear or exponential relationships with seed weight for excluding the seed weight effect. EGV and its related-traits adjusted for seed weight also showed big variation among genotypes. Increased EGV was genetically correlated with increases in breadth and length of early leaves. The broad-sense heritability for EGV was significantly high(81%), but lower than those of leaf breadth(90% for the $2^{nd}$ leaf and 93% for the $3^{rd}$ leaf) and length(87% for the $2^{nd}$ leaf and 89% for the $3^{rd}$ leaf). Significantly positive genetic correlations were found between EGV and the breadth and length of early leaves. The high heritability of early leaf breadth and length coupled with their strong genetic correlation with EGV indicated that the breadth and length of the $2^{nd}\;and\;3^{rd}$ leaf would be used as good indirect indicators for EGV selection in rice breeding program.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.3
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• pp.256-264
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• 2021

Rapeseed (Brassica napus L.) is generally sown in late autumn and harvested in early summer in Korea, however, spring cultivation has also been attempted in some areas because frequent climate changes induce reducing productivity. Therefore, there is a need for a transplanting technology that is relatively easy to control of cropping season according to changes in cultivation conditions. In this study, to find out the optimal characteristics of seedlings for machine transplanting of spring cultivation, seedling morphological characteristics were investigated according to the seedling age of three varieties for 2020 and 2021. The hypocotyl length was less than 2 cm in both years and the 40-day-old seedling was the shortest among all seedling ages. The number and size of leaf were increased with longer seedling age in both years. To evaluate seedling quality, total seedling length, seedling weight, and impact resistance were measured before transplanting. Total seedling length was the longest in 40-day-old seedlings and the shortest in 25-day-old seedlings in both years. In the case of seedling weight, no significant differences were observed depending on the seedling age and the impact resistance increased with increasing seedling age. Finally, 'Jungmo7001', 'Naehan', and 'Tamla' showed a high transplanting rate in seedlings grown for more than 30 days, 35 days, and 40 days, respectively, in the field using a general transplanter. These results suggest that the proper seedling age for transplanting is limited depending on the rapeseed varieties. The suitable seedling cultivation method can be selected for different cultivation environments.