• The Plant Pathology Journal
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• 제29권4호
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• pp.471-476
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• 2013

Plants are frequently exposed to numerous environmental stresses such as dehydration and high salinity, and have developed elaborate mechanisms to counteract the deleterious effects of stress. The phytohormone abscisic acid (ABA) plays a critical role as an integrator of plant responses to water-limited condition to activate ABA signal transduction pathway. Although perception of ABA has been suggested to be important, the function of each ABA receptor remains elusive in dehydration condition. Here, we show that ABA receptor, pyrabactin resistance-like protein 8 (PYL8), functions in dehydration conditions. Transgenic plants overexpressing PYL8 exhibited hypersensitive phenotype to ABA in seed germination, seedling growth and establishment. We found that hypersensitivity to ABA of transgenic plants results in high degrees of stomatal closure in response to ABA leading to low transpiration rates and ultimately more vulnerable to drought than the wild-type plants. In addition, high expression of ABA maker genes also contributes to altered drought tolerance phenotype. Overall, this work emphasizes the importance of ABA signaling by ABA receptor in stomata during defense response to drought stress.

• 한국작물학회지
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• 제48권6호
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• pp.506-515
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• 2003

이 논문은 한발저항성이 다른 6개 보리 품종의 한발에 따른 생장, 잎의 수분포텐셜(leaf water potential, LWP), 상대함수량(leaf relative water content, RWC), 삼투압(leaf osmotic potential, OP), 삼투조정(osmotic adjustment, OA), 팽압(leaf turgor pressure, LTP), 순광합섬, 기공전도도, 엽육전도도, 엽록소형광 등의 변화를 조사하여 비교한 결과를 요약하면 다음과 같다. 1 한발 처리시 토양수분포텐셜은 -0.05㎫이었고. 종료시에는 -0.29㎫로 저하하였다. Dicktoo-S 동보리 1호, Dicktoo-L, Dicktoo-T, 수원쌀보리 365호, 탑골보리 품종의 한발처리구 건물중은 각각 대조구(처리기간종 -0.05㎫ 유지)에 비하여 68%, 69%, 70%, 86%, 55%, 37%를 나타내어 Dicktoo 계통과 동보리1호의 한발저항성이 강하였고, 수원쌀보리 365호와 탑골보리는 한발저항성이 약하였다. 2. 한발저항성이 강한 품종은 삼투조정능력이 커서 한발처리에 따른 RWC와 LWP의 저하가 작았고 팽압유지능력이 컸다. 3. 한발처리에 따라 순광합성이 저하하였고 그 저하정도는 한발저항성이 큰 품종이 작았는데, 이는 한발저항성이 큰 품종이 기공전도도, 엽육전도도 및 PSII 최대양자수율(Fv/Fm)의 저하가 적었기 때문이었다. 4. 결론적으로 저항성이 큰 품종은 삼투조정에 의한 수분유지능력이 크고 이에 따라 광합성저하가 적어 상대적으로 생장의 감소가 적은 것으로 판단되었다.

• 한국작물학회지
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• 제24권3호
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• pp.7-12
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• 1979

748개의 벼 품종을 파종하여 토양수분이 포화된 상태로 30일간 재배한 후 40일간 단수하여 한발을 조장한 다음 각 품종들의 한발에 대한 반응을 검정한 결과는 다음과 같다. 1. 한발처리기간 중 초장의 신장정도는 일본품종들이 가장 컸고 IRRI 도입품종, 한국재래품종 및 Indica / Japonica 품종 순이었다. 2. 한발처리후의 위조정도는 IRRI도입 품종들이 가장 경미하였고 일본도입품종, Indica / Japonica 품종 및 한국재래품종 순이었다. 3. 유묘기 내한성품종으로 원길조, 한양도, YR 52-$_{x}\textrm{BF}_7-67, Satominori, Mamoriaka, 적야난11004, 죽 홍난, IR 937-55-3, IR2735-F_3B-6-2, IR 2871-53-2, $_{x}\textrm{BFI76}^9/Dwan, Khoo Dook Mali-4-2-105, Os6, Palawan, IRAT10, TOS 2583 및 H-l05 등이 발달되었다. 4. 한발처리후의 조장, 조장신장량 및 초장신장율과 위조정도와는 높은 부의 상관이 인정되었다. 5. 한발처리후의 지상부 생체중, 건물중 및 수분함량과 위조정보와는 높은 부의 상관이 인정되었고 특히 수분함량과 위조정도와의 상관이 높았다.(r=0.860, n=21). 6. 한발처리후의 도열병발병과 위조정도와는 높은 정의 상관이 인정되었다. 7. 발아속도 및 처리전초장 (30일묘)과 내한성과는 상관이 없었다.

• 한국작물학회지
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• 제64권4호
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• pp.432-440
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• 2019

Global climate change exerts adverse effects on maize production. Among abiotic stresses, drought stress during the tasseling stage (VT) can increase anthesis-silking intervals (ASI) and decrease yield. We performed an evaluation of ASI and yield using a drought-sensitive line (Ki3) and a drought-tolerant line (Ki11) to analyze the correlation with ASI and yield. Moreover, the de novo data of Ki11 were analyzed to find putative novel transcripts related todrought stress in tropical maize. A total of 182 transcripts, with a log2 ratio >1.5, were found by comparing drought conditions to a control. The top 40 transcripts of high expression levels in the de novo analysis were selected and analyzed with PCR. Of the 40 transcripts, six novel transcripts were detected by quantitative real-time PCR (qRT-PCR) using seedling and VT stage samples. Five transcripts (transcripts_1, 12, 34, 35, and 40) were up-regulated in the Ki11 shoot at seedling stage, and transcripts_1, 12, and 40 were up-regulated at the re-watering stage after 12 h of drought stress. The transcripts_32 and 34 were up-regulated at the VT stage. Hence, transcript_34 possibly plays a significant role in drought tolerance during the seedling and VT stages. The transcript_32 was identified as chloramphenicol acetyltransferase (CAT) by Pfam domain analysis. The function of the other transcripts remained unknown. Further characterization of these novel transcripts in genetic regulation will be of great value for the improvement of maize production.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.13-13
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• 2022

Recently, stable crop production is threatened by the effects of climate change. In particular, it is difficult to consistently maintain agricultural policies due to large price fluctuations depending on the difference in total domestic rice production from year to year. For stable rice production amid changes in the crop growing environment, development of varieties with improved disease resistance and abiotic stress stability is becoming more important. In here, drought and cold tolerant trait have been studied. First, for the development of drought tolerant varieties, we analyzed which agricultural traits are mainly affected by domestic drought conditions. As a result, it was observed that drought caused by the lack of water during transplanting season inhibits the development of the number of tiller and reduces the yield. 'Samgang' was selected as a useful genetic resource with strong drought tolerant and stable tiller number development even under drought conditions by phenotype screening. Three of drought tolerant QTLs were identified using doubled haploid (DH) population derived from a cross between Nacdong and Samgang, a drought sensitive and a tolerant, respectively. Among these QTLs, when qVDT2 and qVDTl1 were integrated, it was investigated that the tiller number development was relatively stable in the rainfed paddy field conditions. It is known that the high-yielding Tongil-type cultivars are severely affected by cold stress throughout the entire growth stage. In this study, we established conditions that can test the cold tolerance phenotype with alternate temperature to treat low temperatures in indoor growth conditions similar to those in field conditions at seedling stage. Three cold tolerant QTLs were explored using population derived from a cross between Hanareum2 (cold sensitive variety, Tongil-type) and Unkwang (cold tolerant variety, Japonica). Among these QTLs, qSCT12 showed strong cold tolerant phenotype, and when all of three QTLs were integrated, it was investigated that cold tolerant score was relatively similar to its donor parent, Unkwang, in our experimental conditions. We are performing that development of new variety with improved cold tolerant through the introduction of these QTLs.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2002년도 추계학술대회
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• pp.41-47
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, $50-80\%$ of the maximum potential yield is lost by these 'environmental or abiotic stresses', which is approximately ten times higher than the loss by biotic stresses. Thus, Improving stress-tolerance of crop plants is an important way to improve agricultural productivity. In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2002년도 춘계학술대회
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• pp.41-47
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these 'environmental or abiotic stresses', which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity. In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.

• The Plant Pathology Journal
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• 제32권6호
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• pp.552-562
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• 2016

Pathogenesis-related proteins play multiple roles in plant development and biotic and abiotic stress tolerance. Here, we characterize a rice defense related gene named "jasmonic acid inducible pathogenesis-related class 10" (JIOsPR10) to gain an insight into its functional properties. Semi-quantitative RT-PCR analysis showed up-regulation of JIOsPR10 under salt and drought stress conditions. Constitutive over-expression JIOsPR10 in rice promoted shoot and root development in transgenic plants, however, their productivity was unaltered. Further experiments exhibited that the transgenic plants showed reduced susceptibility to rice blast fungus, and enhanced salt and drought stress tolerance as compared to the wild type. A comparative proteomic profiling of wild type and transgenic plants showed that overexpression of JIOsPR10 led to the differential modulation of several proteins mainly related with oxidative stresses, carbohydrate metabolism, and plant defense. Taken together, our findings suggest that JIOsPR10 plays important roles in biotic and abiotic stresses tolerance probably by activation of stress related proteins.

• Journal of Plant Biotechnology
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• 제30권4호
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• pp.315-321
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• 2003

고비사막 접경지역의 식물인 Artermisia adamsii의 내건성 및 내동성 증진을 위해 조직배양과 CLP및 Dhn5유전자의 형질전환을 수행하였다. 다양한 호르몬 농도 조건에서의 성장을 확인한 결과, 0.05mg/L의 NAA와 0.5mg/L의 BAP조건과 0.1mg/L의 NAA와 0.5mg/L의 BAP가 포함된 배지의 암조건 하에서 최적의 캘러스 생장을 확인하였으며 유전자 도입 및 유전자의 발현이 확인된 캘러스가 세포 수준에서도 내건성 및 내동성이 증진되었음을 확인하였다. 그러나 Atremisia속 다른 식물과 다르게 조직절편에서 직접 기관분화를 유도하거나 캘러스를 통한 식물체 재생에 어려움이 있어 식물체 수준에서 형질전환에 따른 환경스트레스 내성의 증진을 확인하지 못하고 있다. 앞으로 진행될 A. adamsii의 식물체 재생에 대한 연구를 통해 내동성 및 내건성이 증진된 식물체를 육성하여 고비사막 지역적응력을 조사할 예정이다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2005년도 추계학술발표회 요지
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• pp.282-283
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• 2005