• Journal of Microbiology and Biotechnology
• /
• 제29권7호
• /
• pp.1124-1136
• /
• 2019

Salinity is one of the major abiotic stresses that cause reduction of plant growth and crop productivity. It has been reported that plant growth-promoting bacteria (PGPB) could confer abiotic stress tolerance to plants. In a previous study, we screened bacterial strains capable of enhancing plant health under abiotic stresses and identified these strains based on 16s rRNA sequencing analysis. In this study, we investigated the effects of two selected strains, Bacillus aryabhattai H19-1 and B. mesonae H20-5, on responses of tomato plants against salinity stress. As a result, they alleviated decrease in plant growth and chlorophyll content; only strain H19-1 increased carotenoid content compared to that in untreated plants under salinity stress. Strains H19-1 and H20-5 significantly decreased electrolyte leakage, whereas they increased $Ca^{2+}$ content compared to that in the untreated control. Our results also indicated that H20-5-treated plants accumulated significantly higher levels of proline, abscisic acid (ABA), and antioxidant enzyme activities compared to untreated and H19-1-treated plants during salinity stress. Moreover, strain H20-5 upregulated 9-cisepoxycarotenoid dioxygenase 1 (NCED1) and abscisic acid-response element-binding proteins 1 (AREB1) genes, otherwise strain H19-1 downregulated AREB1 in tomato plants after the salinity challenge. These findings demonstrated that strains H19-1 and H20-5 induced ABA-independent and -dependent salinity tolerance, respectively, in tomato plants, therefore these strains can be used as effective bio-fertilizers for sustainable agriculture.

• Journal of Plant Biotechnology
• /
• 제45권4호
• /
• pp.306-314
• /
• 2018

Korean ginseng (Panax ginseng) has long been cultivated as an important economic medicinal plant. Owing to the seasonal and long-term agricultural cultivation methods of Korean ginseng, they are always vulnerable to various environmental stress conditions. ABSCISIC ACID (ABA) is an essential plant hormone associated with seed development and diverse abiotic stress responses including drought, cold and salinity stress. By modulating ABA responses, plants can regulate their immune responses and growth patterns to increase their ability to tolerate stress. With recent advances in genome sequencing technology, we first reported the functional features of genes related to canonical ABA signaling pathway in P. ginseng genome. Based on the protein sequences and functional genomic analysis of Arabidopsis thaliana, the ABA related genes were successfully identified. Our functional genomic characterizations clearly showed that the ABA signaling related genes consisting the ABA receptor proteins (PgPYLs), kinase family (PgSnRKs) and transcription factors (PgABFs, PgABI3s and PgABI5s) were evolutionary conserved in the P. ginseng genome. We confirmed that overexpressing ABA related genes of P. ginseng completely restored the ABA responses and stress tolerance in ABA defective Arabidopsis mutants. Finally, tissue and age specific spatio-temporal expression patterns of the identified ABA-related genes in P. ginseng tissues were also classified using various available RNA sequencing data. This study provides ABA signal transduction related genes and their functional genomic information related to the growth and development of Korean ginseng. Additionally, the results of this study could be useful in the breeding or artificial selection of ginseng which is resistant to various stresses.

• Molecules and Cells
• /
• 제42권9호
• /
• pp.646-660
• /
• 2019

Abscisic acid (ABA) is a phytohormone essential for seed development and seedling growth under unfavorable environmental conditions. The signaling pathway leading to ABA response has been established, but relatively little is known about the functional regulation of the constituent signaling components. Here, we present several lines of evidence that Arabidopsis Raf-like kinase Raf10 modulates the core ABA signaling downstream of signal perception step. In particular, Raf10 phosphorylates subclass III SnRK2s (SnRK2.2, SnRK2.3, and SnRK2.6), which are key positive regulators, and our study focused on SnRK2.3 indicates that Raf10 enhances its kinase activity and may facilitate its release from negative regulators. Raf10 also phosphorylates transcription factors (ABI5, ABF2, and ABI3) critical for ABA-regulted gene expression. Furthermore, Raf10 was found to be essential for the in vivo functions of SnRK2s and ABI5. Collectively, our data demonstrate that Raf10 is a novel regulatory component of core ABA signaling.

• Journal of Ecology and Environment
• /
• 제47권4호
• /
• pp.241-249
• /
• 2023

Background: This study analyzed the drought responses of five forest tree species grown in Korean peninsula, Korean fir Abies koreana (Ak), eastern white pine Pinus strobus (Ps), keyaki Zelkova serrata (Zs), tulip tree Liriodendron tulipifera (Lt), and Japanese elm Ulmus japonica (Uj). Physiological (chlorophyll, root collar diameter [RCD]) and biochemical responses (non-structural carbohydrates, proline, lipid peroxidase and abscisic acid [ABA]) of the plants grown under mild (MD) and severe drought (SD) were compared. Results: In this study, three soil moisture regimes: control (100% precipitation), MD (60% reduction in precipitation) and SD (20% reduction in precipitation) were applied. Soil moisture content showed high water content in control site compared to MD and SD. A decline in RCD was found for Korean fir, keyaki, and tulip plants, with eastern white pine and Japanese elm showing no significant decline to the prolonged drought exposure (both MD and SD). Total chlorophyll showed a significant decline in Korean fir and tulip, with the sugar levels indicating a significant increase in Korean fir and keyaki species under SD compared to control plants. Non-significant decline in sugar level was noted for eastern white pine and Japanese elm. High accumulation of ABA, malondealdehyde and proline was noted in Korean fir, tulip, and keyaki under SD compared to control. Signs of tree mortality was only observed in Korean fir under MD (38%) and SD (43%). Conclusions: The observed findings indicate the drought responses of five tree species. The majority of the morpho-physiological (especially mortality) and biochemical variables assessed in our study indicate superior long-term drought resistance of Ps and Uj compared to the highly sensitive Ak, and moderately sensitive Lt and Zs. The results provided will help species selection for afforestation programs and establishment of sustainable forests, especially of drought-tolerant species, under increased frequency and intensity of spring and summer droughts.

• 생물환경조절학회지
• /
• 제28권4호
• /
• pp.352-357
• /
• 2019

본 연구는 사과나무 '홍로'와 '후지'의 내재휴면 기간 중 휴면타파에 유효한 한계온도 범위를 알아보고자 수행하였다. 저온 축적에 의한 내재휴면 타파 여부를 확인하기 위하여 온도 처리구별로 발아율을 조사한 결과 '홍로' $-5^{\circ}C$ 처리구를 제외한 모든 처리구에서 발아율이 50% 이상으로 나타났다. 또한 '후지'의 온도 처리구별 발아율은 $-5^{\circ}C$ 처리구에서도 86.3%로 휴면이 타파되었다. 탄수화물과 무기성분의 변화는 처리간 유의한 차이는 있었으나 일정한 경향이나 특이한 변화를 나타내지 않았다. 그러나 유리당 분석 결과 sorbitol 함량은 휴면 타파 여부에 따라 휴면이 타파되지 않은 '홍로' $-5^{\circ}C$ 처리구의 경우 29.62mg/g으로 높게 나타났으며, 휴면이 타파된 것으로 판단되는 처리구는 낮은 수준이였다. 호르몬 분석결과 휴면이 타파되지 않은 '홍로' $-5^{\circ}C$ 처리구의 경우 ABA (abscisic acid)와 JA (jasmonic acid)는 각각 176.48, 15.72ng/g으로 높게 나타났으며, 모든 처리구에서 휴면이 타파된 것으로 나타난'후지'의 경우 ABA, JA, SA(salicylic acid) 함량이 '홍로' 품종보다 유의하게 낮게 나타났다. 본 연구 결과 휴면 타파에 유효한 한계온도 범위는 품종에 따라 다르며 '홍로'는 $-5^{\circ}C$에서 발아율이 30.3%로 휴면이 타파되지 않은 것으로 나타났으며, '후지'는 $0^{\circ}C$ 이하인 $-5^{\circ}C$에서도 86.3%로 높게 나타나 저온 축적의 효과가 있는 것으로 판단된다.

• 한국식물병리학회지
• /
• 제14권3호
• /
• pp.240-246
• /
• 1998

A cDNA encoding desiccation-related protein was isolated from a flower bud cDNA library of Chinese cabbage (C-DH) and its nucleotide sequence was characterized. It contains 679 bp nucleotides with 501 bp open reading frame. The amino acid sequence of the putative protein showed the highest amino acid sequence homology (79 % identity) to dehydrin protein in Gossypium hirsutum. Also, the C-DH shares 48-52% amino acid sequence identity with the other typical dehydrin proteins in plant cells. When the amino acid sequence of their proteins were aligned, several peptide motifs were well conserved, of which function has to be solved. Particularly the C-DH contains 15 additional amino acids at its N-terminus. Genomic Southern blot analysis using the coding region of C-DH showed that the C-DH consists of a single copy gene in Chinese cabbage genome. The C-DH mRNA, whose transcript size is 0.7 kb, was expressed with a tissue-specific manner. It was highly expressed in seed, flower buds and low expression as detected in root, stem or leaf tissues of Chinese cabbage. And the transcript level of C-DH was significantly induced by the treatment of plant hormone, abscisic acid and water-deficit conditions.

• 한국산림과학회지
• /
• 제32권1호
• /
• pp.64-72
• /
• 1976

라디아타 소나무의 엽속삽목(葉束揷木)을 시험관내(試驗管內)에서 실시(實施)하였던바 다음과 같은 결과(結果)를 얻었다. 1. 3년생(年生), 7년생(年生), 11년생(年生), 18년생(年生) 및 40여년생(餘年生)의 모수별(母樹別) 평균(平均) 발근율(發根率)은 각각(各各) 57%, 47%, 18%, 4% 및 2%이었으며 모수령(母樹令)이 증가(增加)할수록 엽속삽수(葉束揷穗)이 발근율(發根率)은 감소(減少)되었다. 2. IBA(indolebutyric acid), ABA(abscisic acid) 및 몇 가지 살균제(殺菌劑)의 처리(處理)는 발근(發根)에 별영향(別影響)을 미치지 못하였다. 3. 온도처리(溫度處理) $20^{\circ}/10^{\circ}C$(주간온도(晝間溫度)/야간온도(夜間溫度))와 일조(日照) 18시간처리구(時間處理區)의 엽속삽수(葉束揷穗)는 동온도처리(同溫度處理)와 일조(日照) 10시간(時間) 처리구(處理區)에서 보다 발근(發根)이 훨씬 좋았고 $15^{\circ}/10^{\circ}C$의 온도처리(溫度處理)와 10시간(時間)의 일조처리구(日照處理區)에서 발근(發根)이 가장 불량(不良)하였다. 4. 시험관내(試驗管內) 엽속삽목(葉束揷木)이 발근율(發根率)은 온실내(溫室內) 발근율(發根率)에 비(比)하여 (특(特)히 노령모수(老令母樹)에서 채취(採取)한 클론의 경우(境遇)) 저조(低調)한 경향(傾向)을 보였으므로, 시험관내(試驗管內) 삽목법(揷木法)을 통(通)하여 발근율(發根率) 자체(自體)의 증진(增進)을 기대(期待)하기는 어려우나 여러 가지 요인조작(要因操作)이 용역(容易)하여 발근생리(發根生理)에의 응용(應用)이 가능(可能)할 것으로 사료(思料)된다.

• 농업생명과학연구
• /
• 제46권6호
• /
• pp.9-15
• /
• 2012

본 연구는 식물생장조절물질을 활용하여 '캠벨얼리' 포도의 품질향상 증진 방안을 마련하기 위하여 실시하였다. 전엽 3~5엽기에 화방에 대한 지베렐린($GA_3$) $5mg{\cdot}L^{-1}$ 엽면처리는 '캠벨얼리' 포도의 과경, 과방중, 가용성당함량, 과피의 착색을 증진시켰다. 전엽 3~4엽기의 화방에 대한 $GA_3$ $5mg{\cdot}L^{-1}$과 ABA $20\;mg{\cdot}L^{-1}$ 혼용처리는 과립 비대와 과축 신장을 저해하지 않았으며 포도 과피의 안토시아닌 축적에 효과적이었다. '캠벨얼리' 포도의 전엽 3~4엽기에 화방에 대한 thidiazuron $2.5mg{\cdot}L^{-1}$과 $GA_3$ $5mg{\cdot}L^{-1}$ 혼용처리는 가용성고형물 함량 증진과 산함량 감소를 촉진하여 과실 품질이 증대되었다.

• Journal of Ginseng Research
• /
• 제29권2호
• /
• pp.71-79
• /
• 2005

In vitro studies using detached inflorescences with peduncles were conducted to investigate flower abscission agents in North American ginseng (Panax quinquefolius L.). Of the nine compounds studied only three, ammonium thiosulphate (ATS), abscisic acid (ABA) and ethephon induced abscission. Anilazine, benzyladenine, carbaryl, gibberellic acid, napthaleneacetic acid and thidiazuron did not induce abscission. ATS dip treatments did not induce abscission but the spray treatments induced $60.5\%$ abscission at $1500\;mg{\cdot}L^{-1}$ and $33.1\%$ at $3000\;mg{\cdot}L^{-1}$. Severe chlorophyll loss occurred on all inflorescences treated with ATS. Both ABA dip treatments and a $250\;{\mu}mol{\cdot}L^{-1}$ spray treatment caused abscission $(40\%)$ without adverse effects, and timing of ABA application was important. Because ABA was only significant in the dip treatments, ABA may not be a practical option for field use on ginseng. Ethephon sprays induced more abscission as the season progressed and as the concentration increased. As the dip concentrations of ethephon increased, the abscission rate decreased and the health of the inflorescences declined. The $1500\;mg{\cdot}L^{-1}$ spray of ethephon gave consistent abscission results over the glowing season with little phytotoxicity. Treatment with the competitive ethylene inhibitor 1-methylcy-clopropene (1-MCP) suggested that flower abscission was due to the liberation of ethylene from the breakdown of ethephon.

• Journal of Plant Biology
• /
• 제36권3호
• /
• pp.267-273
• /
• 1993

Promoters of the chlorophyll a/b bidning protein genes, cab1, and cab2, of Arabidopsis thaliana were studied for their functions in differential expression during greening of etiolated shoots. The etiolated shoots were derived from leaves of transgenic tobacco plants with the cab-CAT (chloramphenicol acetyltransferase) translational fusions, and CAT activity was measured to monitor the activities of the cab promoters. Cab1 promoter activity increased rapidly and showed saturation after about 24 hours of greening, but that of cab2 increased with about 2 day-lag period and showed saturation after 6 days. Cab1 promoter activity was more sensitive to levulinic acid (LA) compared with cab2 activity. Cab2 promoter activity was inhibited more sensitively by chloramphynicol (CAP) than by inhibitors of Chl formation. Cab1 promoter activity was, however, inhibited less sensitively by CAP than by LA. The treatment of abscisic acid (ABA) did not block Chl synthesis so significantly as LA treatment did, and cab2 promoter activity was much less sensitive to ABA compared with that of cab1. These results suggest that cab1 expression is strongly related with Chl formation, possibly with $\delta$-aminolevulinic acid accumulation, and cab2 expression is suppressed more by the blockage of translation of Chl a-apoproteins than by the blockage of Chl a accumulation.