• 한국환경과학회지
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• 제28권11호
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• pp.907-915
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• 2019

This study aims to identify the most tolerant species under salinity stress from amongst Asteraceae and Poaceae. The seeds of six species were exposed to different concentrations of $CaCl_2$ (0, 9, 18, 45, 90 mM) and NaCl (0, 17, 34, 85, 170 mM), and germination was measured once every two days. The results indicated that percent germination of the six species of Asteraceae and Poaceae seeds were affected differently by changes in salinity concentration. Seed germination was reduced as salinity levels increase, and longer mean germination times correlated to lower percent germination and earlier germination cessation. Both Asteraceae and Poaceae seeds had the highest germination rates at 18 mM $CaCl_2$ and 34 mM NaCl, and seed germination and growth were severely reduced at salinities greater than 90 mM $CaCl_2$ and 170 mM NaCl. In the seeds of Poaceae, salt resistance was strong in the order of Miscanthus sinensis Andersson, Pennisetum alopecuroides (L.) Spreng., and Phragmites communis Trin. In the seeds of Asteraceae, salt resistance was strong in the order of Dendranthema zawadskii var. latilobum (Maxim.) Kitam, Aster yomena (Kitam.) Honda, and Dendranthema boreale (Makino) Ling ex Kitam.. Overall, the germination rate was higher in Asteraceae than in Poaceae. This study demonstrated that Dendranthema zawadskii var. latilobum (Maxim.) Kitam. is the most tolerant species and that a relationship exists between the salt tolerance of percent germination and the mean germination time in the leaves.

• Journal of Plant Biotechnology
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• 제29권4호
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• pp.247-252
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• 2002

1.5% NaCl이 함유된 배지에 캘러스를 치상하여 방사선을 처리한 결과 무처리구보다 처리구 (30, 50 Gy)에서 캘러스 생존율 및 재분화율이 증가하여 내염성 캘러스를 선발하는데 방사선의 적용이 효과적임을 알 수 있었고, 내염성 캘러스에서 재분화된 M$_3$세대 종자에서 내염성 계통들은 모품종보다 초장, 근장 및 근수의 생육이 우수하여 이러한 계통은 내염성 연구를 위한 유용한 유전자원으로 이용할 수 있을 것으로 생각된다. 또한 RAPD 기술은 대조구와 내염성 캘러스에서 재분화된 계통을 구분하는데 유용한 기술임을 알 수 있었다.

• Molecules and Cells
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• 제21권2호
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• pp.197-205
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• 2006

We used cDNA microarrays to monitor the transcriptome of ozone stress-regulated genes (ORGs) in two pepper cultivars [Capsicum annuum cv. Dabotop (ozone-sensitive) and Capsicum annuum cv. Buchon (ozone-tolerant)]. Ozone stress up- or down-regulated 180 genes more than three-fold. Transcripts of 84 of these ORGs increased, transcripts of 88 others diminished, and those of eight either accumulated or diminished at different time points in the two cultivars or changed in only one of the cultivars. 67% (120) of the ORGs were regulated differently in ozone-sensitive and ozone-tolerant peppers, most being specifically up-regulated in the ozone-sensitive cultivar. Many were also represented in the plant defense transcriptome against non-host pathogen infection, and some in the transcriptomes for cold, drought, and salinity stresses.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.306-306
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• 2017

Screening for drought and salinity tolerance was undertaken for selected Philippine upland rice landraces during germinative and seedling stages to identify varieties which can potentially be grown in marginally dry and saline soils. While increasing PEG and NaCl concentrations caused obvious signs of injury to all rice genotypes, considerable varietal differences were noted in the nature of responses providing evidence that these genotypes possess broad intraspecific genetic variations for drought and salt tolerance. Inconsistent responses of these varieties during both growth stages highlight complexities involved in stress responses and underscore the futility of utilizing a single stage in the rice plant's life cycle for physiological screening. Notwithstanding these perplexing responses, G_Katiil and Ml-Pilit Tapul were observed to thrive relatively well despite increased salt and drought stress during early growth stages and may therefore possess genes needed in crop improvement efforts for drought and salinity tolerance. While these results do not reflect the entire spectrum of adaptive expression to drought and salinity stress during the life cycle of the upland rice plant, they nonetheless provide an easy, reliable and reproducible method for preliminary identification of drought and salt tolerant rice varieties.

• 한국초지조사료학회지
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• 제43권1호
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• pp.42-49
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• 2023

The plant-specific NAC transcription factors control various biological processes, including plant development and stress responses. We have isolated an ANAC032 gene, one of the NAC transcription factor family, which was highly activated by multi-abiotic stresses, including high salt and drought in Arabidopsis. Here, we generated transgenic plants constitutively expressing ANAC032 and its knockout to identify the functional roles of ANAC032 in Arabidopsis under abiotic stress responses. The ANAC032-overexpressing plants showed enhanced tolerance to salinity and drought stresses. The anac032 knockout mutants were observed no significant changes under the high salt and drought conditions. We also monitored the expression of high salt and drought stress-responsive genes in the ANAC032 transgenic plants and anac032 mutant. The ANAC032 overexpression upregulated the expression of stress-responsive genes, RD29A and ERD10, under the stresses. Thus, our data identify that transcription factor ANAC032 plays as an enhancer for salinity and drought tolerance through the upregulation of stress-responsive genes and provides useful genetic traits for generating multi-abiotic stress-tolerant forage crops.

• Ocean Science Journal
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• 제40권1호
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• pp.17-24
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• 2005

A series of experiments were conducted to develop standard test organisms and test protocols for measuring sediment toxicity using candidate amphipods such as Mandibulophoxus mai, Monocorophium acherusicum, Haustorioides indivisus, and Haustorioides koreanus, which are indigenous to Korea. The relevant association of test species with sediment substrates was one of the important factors in sediment bioassay. The indigenous amphipods M mai and M. acherusicum were well associated with test sediments when they were exposed to various sediment substrates from sand to mud. The tolerant limits to various physico-chemical factors affecting bioassay results such as temperature, salinity and ammonia, as well as sensitivities to reference toxicant and contaminated sediments, were investigated using M. mai and M. acherusicum in the present study. These amphipods were tolerant to relatively wide ranges of salinity $(10{\sim}30\;psu)$ and ammonia (<50 ppm), and displayed relevant sensitivity to temperature as well. They are more sensitive to Cd, the reference toxicant, when compared to the standard test species used in other countries. Field-sediment toxicity tests revealed that M. mai would be more sensitive to sediment-associated pollutants than M. acherusicum, while the sensitivity of M. acherusicum was comparable to that of Leptocheirus plumulosus, which has been used as a standard test species in the United States of America. Overall results of this first attempt to develop an amphipod sediment toxicity test protocol in Korea indicated that M. mai and M. acherusicum would be applicable in the toxicity assessment of contaminated sediments, following the further evaluation encompassing various ecological and toxicological studies in addition to test method standardization.

• 한국환경농학회지
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• 제40권4호
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• pp.345-352
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• 2021

BACKGROUND: Salinity is one of the major limiting factors in agriculture that affect the growth and productivity of crops. It is economically difficult to artificially purify the soil affected by salt. Therefore, the use of plant growth-promoting bacteria (PGPB) in an effort to reduce stress caused by salt is emerging as a cost-effective and environment-friendly method. In this study, the purpose was to isolate the salt-tolerant bacteria from the rhizosphere soil and identify their ability to promote plant growth under salt stress condition. METHODS AND RESULTS: The isolates KST-1, KST-2, AST-3, and AST-4 that showed plant growth-promoting activity for barley in salt conditions were close to Bacillus cereus (KST-1, KST-2, and AST-4) and Bacillus thuringiensis (AST-3) and showed high salt tolerance up to 7% of additional NaCl to the media. When inoculated to barley, the strains had only minor effect on the length of the barley. However, the concentrations of chlorophyll in the barley leaves were found to be higher from the bacteria-inoculated pots than those from the uninoculated control. In particular, the chlorophyll concentration in Bacillus cereus AST-4 experiment was 5.45 times higher than that of the uninoculated control under the same experimental condition. CONCLUSION(S): The isolated salt-tolerant bacteria were found to influence on chlorophyll concentration of the barley. As represented by the strain AST-4, microbes may suggest a cost-effective and environmentally benign method to alleviate salt stress of crops cultivated in salt-accumulated soils such as reclaimed lands.

• 한국토양비료학회지
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• 제49권4호
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• pp.355-367
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• 2016

Soil salinization refers to the buildup of salts in soil to a level toxic to plants. The major factors that contribute to soil salinity are the quality, the amount and the type of irrigation water used. The presented review discusses the different sources and causes of soil salinity. The effect of soil salinity on biological processes of plants is also discussed in detail. This is followed by a debate on the influence of salt on the nutrient uptake and growth of plants. Salinity decreases the soil osmotic potential and hinders water uptake by the plants. Soil salinity affects the plants K uptake, which plays a critical role in plant metabolism due to the high concentration of soluble sodium ($Na^+$) ions. Visual symptoms that appear in the plants as a result of salinity include stunted plant growth, marginal leaf necrosis and fruit distortions. Different strategies to ameliorate salt stress globally include breeding of salt tolerant cultivars, irrigation to leach excessive salt to improve soil physical and chemical properties. As part of an ecofriendly means to alleviate salt stress and an increasing considerable attention on this area, the review then focuses on the different plant growth promoting bacteria (PGPB) mediated mechanisms with a special emphasis on ACC deaminase producing bacteria. The various strategies adopted by PGPB to alleviate various stresses in plants include the production of different osmolytes, stress related phytohormones and production of molecules related to stress signaling such as bacterial 1-aminocyclopropane-1-carboxylate (ACC) derivatives. The use of PGPB with ACC deaminase producing trait could be effective in promoting plant growth in agricultural areas affected by different stresses including salt stress. Finally, the review ends with a discussion on the various PGPB activities and the potentiality of facultative halophilic/halotolerant PGPB in alleviating salt stress.

• 한국어류학회지
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• 제22권1호
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• pp.9-16
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• 2010

본 연구에서는 광염성 송사리 Oryzias dancena 성체 및 자어의 염분도 변화에 대한 내성 및 생존 능력을 평가하고자 다양한 염분도 변화 처리를 수행하였다. 담수로부터 고 염분도 조건으로의 급격한 염분도 증가 노출 처리에 대하여 O. dancena 성체는 $40^{\circ}/_{\circ\circ}$염분도 변화 폭까지 생존의 장애 없이 빠르게 적응할 수 있는 것으로 관찰되었으며, 단계적인 순치를 통할 경우 최대 $75^{\circ}/_{\circ\circ}$의 염분도 조건까지 생존이 가능하였다. 염분도의 감소 처리에서 O. dancena 성체는 $60^{\circ}/_{\circ\circ}$ 이상의 급격한 감소 폭에서도 우수한 생존율을 나타내였다. 성체와 달리 O. dancena 자어는 급격한 염분도 증가에 대한 삼투압 조절 능력 (hyper-osmoregulation)이 유의적으로 낮아 약 $15^{\circ}/_{\circ\circ}$ 이상의 염분도 증가에서는 생존에 큰 장애를 겪는 것으로 나타났다. 그러나 초기 발달 단계에 있는 자어의 염분도 변화에 대한 내성은 최초 염분도 처리 농도에 따라 염분도 변화에 대한 내성 폭이 크게 영향을 받는 것으로 관찰되었다. 초기 발달 단계에서 O. dancena 자어는 염분도 증가 보다는 염분도 감소 시 삼투압 조정 능력 (hypo-osmoregulation)이 더 높은 것으로 나타나 $40^{\circ}/_{\circ\circ}$에서 완전 담수로의 염분도 변화에서도 우수한 생존 능력을 보였다.

• 한국수산과학회지
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• 제46권6호
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• pp.827-834
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• 2013

The effects of environmental factors, such as irradiance, daylength, salinity, and desiccation, on the growth of Lithophyllum yessoense and Hildenbrandia rubra sporelings were examined. Sporelings of each species were cultured with 10, 50, 80, 120, $150{\mu}mol$ photon $m^{-2}s^{-1}$ for 14 days and their maximum growth occurred under $80{\mu}mol$ photon $m^{-2}s^{-1}$. Germlings of both species survived for 21 days in darkness, and even the L.yessoense germlings grew. In the salinity experiment, sporelings of each species survived for 7 days and died after 14 days under 20 and 25 psu, but the sporelings grew well under 34 psu. Physiological features of each species with respect to the evaluated daylengths (8, 12, 14 and 16 h) were slightly different, and maximal growth occurred at 16 h for L. yessoense and at 14 h for H. rubra sporelings. Mortality of the sporelings increased with the exposure period, but H. rubra was less tolerant to desiccation than L. yessoense. In conclusion, sporelings of the two species showed similar growth responses to various environmental factors with slightly different physiological features with respect to salinity, daylength, and desiccation. However, more ecological and physiological studies on slow-growing crustose algae are required to elucidate the expansion of barren ground around the coastal areas of Korea.