• The Plant Pathology Journal
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• 제37권5호
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• pp.494-501
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• 2021

Pseudomonas cichorii secretes effectors that suppress defense mechanisms in host plants. However, the function of these effectors, including avirulence protein E1 (AvrE1), in the pathogenicity of P. cichorii, remains unexplored. In this study, to investigate the function of avrE1 in P. cichorii JBC1 (PcJBC1), we created an avrE1-deficient mutant (JBC1^ΔavrE1) using CRISPR/Cas9. The disease severity caused by JBC1^ΔavrE1 in tomato plants significantly decreased by reducing water soaking during early infection stage, as evidenced by the electrolyte leakage in infected leaves. The disease symptoms caused by JBC1^ΔavrE1 in the cabbage midrib were light-brown spots compared to the dark-colored ones caused by PcJBC1, which indicates the role of AvrE1 in cell lysis. The avrE1-deficient mutant failed to elicit cell death in non-host tobacco plants. Disease severity and cell death caused by JBC1^ΔavrE1 in host and non-host plants were restored through heterologous complementation with avrE1 from Pseudomonas syringae pv. tomato DC3000 (PstDC3000). Overall, our results indicate that avrE1 contributes to cell death during early infection, which consequently increases disease development in host plants. The roles of PcJBC1 AvrE1 in host cells remain to be elucidated.

• Journal of Microbiology and Biotechnology
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• 제18권1호
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• pp.67-73
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• 2008

The potential of the exopolysaccharide (EPS) from a Serratia sp. strain Gsm01 as an antiviral agent against a yellow strain of Cucumber mosaic virus (CMV-Y) was evaluated in tobacco plants (Nicotiana tabacum cv. Xanthi-nc). The spray treatment of plants using an EPS preparation, 72h before CMV-Y inoculation, protected them against symptom appearance. Fifteen days after challenge inoculation with CMV-Y, 33.33% of plants showed mosaic symptoms in EPS-treated plants compared with 100% in the control plants. The EPS-treated plants, which showed mosaic symptoms, appeared three days later than the controls. The enzyme-linked immunosorbent assay (ELISA) and reverse transcriptase polymerase chain reaction (RT-PCR) analyses of the leaves of the protected plants revealed that the EPS treatment affected virus accumulation in those plants. Analysis of phenylalanine ammonia lyase, peroxidase, and phenols in protected plants revealed enhanced accumulation of these substances. The pathogenesis-related (PR) genes expression represented by PR-lb was increased in EPS-treated plants. This is the first report of a systemic induction of protection triggered by EPS produced by Serratia sp. against CMV-Y.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.71-80
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• 2005

Effects of low temperature ($8^{\circ}C$) on the hydraulic conductivity of young roots of a chilling-sensitive (cucumber; Cucumis sativus L.) and a chilling-resistant (figleaf gourd; Cucurbita ficifolia Bouche) crop have been measured at the levels of whole root systems (root hydraulic conductivity, $Lp_r$) and of individual cortical cells (cell hydraulic conductivity, Lp). In figleaf gourd, there was a reduction only in hydrostatic $Lp_r$ but not in osmotic $Lp_r$ suggesting that the activity of water channels was not much affected by low root temperature (LRT)treatment in this species. Changes in cell Lp in response to chilling and recovery were similar asroot level, although they were more intense at the root level. Roots of figleaf gourd recovered better from LRT treatment than those of cucumber. In figleaf gourd, recovery (both at the root and cell level) often resulted in Lp and $Lp_r$ values which were even bigger than the original, i.e. there was an overshoot in hydraulic conductivity. These effects were larger forosmotic (representing the cell-to-cell passage of water) than for hydrostatic $Lp_r$. After a short term (1 d) exposure to $8\;^{\circ}C$ followed by 1 d at $20\;^{\circ}C$, hydrostatic $Lp_r$ of cucumber nearly recovered and that of figleaf gourd still remained higher due to the overshoot. On the contrary, osmotic $Lp_r$ and cell Lp in both species remained high by a factor of 3 as compared to the control, possibly due to an increased activity of water channels. After pre-conditioning of roots at LRT, increased hydraulic conductivitywas completely inhibited by $HgCl_2$ at both the root and cell levels. Different from figleaf gourd, recovery from chilling was not complete in cucumber after longer exposure to LRT. It is concluded that at LRT, both changes in the activity of aquaporins and alterations of root anatomy determine the water uptake in both species. To better understand the aquaporin function in plants under various stress conditions, we examined the transgenic Arabidopsisand tobacco plants that constitutively overexpress ArabidopsisPIP1;4 or PIP2;5 under various abiotic stress conditions. No significant differences in growth rates were found between the transgenic and wild-type plants under favorable growth conditions. By contrast, overexpression of PIP1;4 or PIP2;5 had a negative effect on seed germination and seedling growth under drought stress, whereas it had a positive effect under cold stress and no effect under salt stress. Measurement of water transport by cell pressure probe revealed that these observed phenotypes under different stress conditions were closely correlated with the ability of water transport by each aquaporin in the transgenic plants. Together, our results demonstrate that PIP-type aquaporins play roles in seed germination, seedling growth, and stress response of Arabidopsis and tobacco plants under various stress conditions, and emphasize the importance of a single aquaporin-mediated water transport in these cellular processes.

• 식물조직배양학회지
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• 제26권3호
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• pp.197-203
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• 1999

수분후 담배의 배에 중이온 beam ($^{14}$ N)을 조사하여 얻은 종자로부터 albino식물체를 분리하여 기내 생장과 분화의 특성을 검토하였다. 기내에서 생장시킨 albino식물체는 엽록소함량이 급격한 감소를 나타내었고 기공수는 잎의 이면 및 표면 표피에서 녹색 식물체 보다 많았다 연속광 조건하의 탄소원을 첨가한 MS배지에서 albino개체는 절간이 신장하지 않았으나 10.0mg/L 의 GA$_3$처리로 절간신장이 회복되었다. 잎절편 배양시 albino식물체는 1.0 mg/L 의 BAP와 kinetin의 단용처리로 다수의 신초를 형성하였고, 1.0mg/L의 2,4-D와 NAA의 단용처리로 다량의 캘러스를 형성하였다. 잎절편에서 유도된 albino 캘러스에 1.0mg/L BAP+0.1mg/L NAA를 혼용처리하면 다수의 식물체가 재분화 되었다. 이와같이 albino 식물체는 다경줄기 형성, 캘러스 형성, 캘러스로부터 재분화율 등이 녹색 식물체와 차이가 없었다. 또한 NAA와 BAP를 혼용처리 하였을 때 잎절편으로부터 기관분화의 유형도 정상주와 비슷하였다. 이러한 결과는 본 albino담배 변이체가 색소체 함량의 급감과 같은 광합성과 관련된 기능에서는 결손을 보이고 있음에도 불구하고 조직수준의 기관분화계에는 이상이 없다는 것을 시사한다.

• 한국토양비료학회지
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• 제18권1호
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• pp.89-93
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• 1985

질소(窒素)와 무기양(無機陽)이온이 다른 작물(作物)보다 풍부한 연초제조부산물(煙草製造副産物)인 담배부스러기를 재료(材料)로 하여 비료물질(肥料物質)을 개발하려고 하였다. 담배부스러기를 무게감소율(減少率)로 50%되게 탄화(炭化)시킨 후 유리된 칼륨으로 인한 염기성을 pH 7.0정도 되게 질산(窒酸)과 인산(燐酸)으로 중화(中和)하면 질소(窒素) 4%{유기태(有機態) 질소(窒素)(담배부스러기에 함유(含有)된 질소) 2%, 질산태실소 2%}, 인산(燐酸) 2%, 칼륨6%이상(以上)인 비료물질(肥料物質)이 되었다. 관행(貫行)의 연초육묘시(煙草育苗時)에 시비(施肥)되는 전체(全體) 질소량(窒素量)을 위의 중화이분탄화물(中和泥粉炭化物)로서 전량기비(全量基肥)로 $1kg/110{\ell}$ 정도를 상토(床土)와 혼합시용하여 육묘(育苗)한 결과 관행(貫行)과 같이 추비(追肥)를 시용(施用)하지 않고도 양호(良好)한 생육(生育)을 보였다. 이러한 효과(效果)는 속효성인 질산태질소와 완효성인 담배가루 구성물질의 유기태질소(有機態窒素)가 탄화물(炭化物)에 함유(含有)되고 또한 다량함유(多量含有)된 칼륨이 영양원(營養源)으로 되기 때문인 것으로 생각되었다.

• Journal of Plant Biotechnology
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• 제31권4호
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• pp.313-317
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• 2004

MMPs는 $Zn^{2+}$-의존성 endopeptidase로서 세포외 기질을 분해하는 능력을 갖고 있다. 본 연구에서는 담배식물체에서 잎의 발생단계별로 분비되는 MMPs의 활성과 환경 스트레스에 의한 MMPs의 활성을 조사하였다. 그 결과 MMPs의 활성은 기부 부위의 완전히 성숙한 잎보다 엽신의 확장이 일어나고 있는 어린잎에서 높았다. 이는 식물체에서 잎 신장을 위한 세포내 공간 형성 및 조직재구성에 MMPs가 중요한 단백질분해효소로 작용함을 시사하였다. 또한 환경 스트레스에 대한 반응으로서 MMPs의 활성을 조사한 결과 염처리와 병원균 감염에 의해 각각 1.2배와 1.5배의 증가를 보였다. 이러한 결과는 식물체가 발생단계 외에도 불리한 환경에 대한 방어 수단으로 MMPs가 생성 분비함을 알 수 있었다.

• Journal of Plant Biotechnology
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• 제30권1호
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• pp.103-108
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• 2003

본 연구는 난분해성 농약의 자연분해를 유도하기 위하여 ${\gamma}$-BHC를 탄소원으로 이용하여 호기적으로 자화하는 미생물 (Sphingomonas paucimobilis)에서 분리된 탈염소화효소 중 ${\gamma}$-BHC분해의 첫단계에 관여하는 linA유전자를 담배에 도입하여 BHC에 활성을 나타내는 형질전환 시물체를 만들었다. LinA 유전자를 함유한 pJK 108 백터를 제작하여. Agrobacterium를 이용한 leaf disk transformation 방법으로 담배에 형질전환시켰으며, northern분석 및 Southern분석을 통해 형질전환 개체에서 linA유전자의 도입과 linA유전자 유래의 mRNA가 전사됨을 확인하였다. Western 분석에서 linA단백질의 발현을 확인하였고, gas chromatography를 이용하여 담배 형질전환 개체에서 BHC가 ${\gamma}$-PCCH와 1,2.4-TCB로 분해되는 것을 확인하였다.

• The Plant Pathology Journal
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• 제18권5호
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• pp.231-236
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• 2002

Bemisia tabaci Genn. is an important pest worldwide because of its ability to cause damage by direct feeding and its role as a vector of some viruses including geminiviruses. The first report of Tobacco leaf curl virus (TLCV), a Geminiviruses, in Indonesia was in 1932 when the virus was found infecting tobacco plants in Central Java. The characteristic symptoms of TLCV included upward curling of the leaf edge, vein thickening, and sometimes the occurrence of enation on the underside of the leaves. Basic studies were carried out to elucidate the characteristics of TLCV transmission by its vector, B. tabaci. A single whitefly was able to transmit the virus and the efficiency of transmission was increased when the number of adult whiteflies was increased up to 20 per plant. Inoculation access period of 1 h could cause transmission up to 20% and the optimum inoculation access period was 12 h. Acquisition access period of 30 minutes resulted in 70% transmission while 1(10% transmission occurred with a 24-h acqui-sition access period. The virus was proven to be persistently but not transovarially transmitted. Discrete fragments of 1.6 kb were observed when polymerase chain reaction method was applied to detect the virus in viruliferous nymphs and individual adults of B. tabaci, while no bands were obtained from non-viruliferous nymphs and adults.

• 한국연초학회지
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• 제22권1호
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• pp.71-75
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• 2000

The genetic makeup could be the most important among many factors affecting yield and quality of tobacco(Nicotiana tabacum L.). The mammoth gene found in N. tabacum is associated with greater leaf number and poor leaf quality. This study was carried out to obtain the basic information about the inheritance of mammoth gene and white flower color. Two flue-cured breeding lines, KF 9373-2 and KF 8832-85, F$_1$, F$_2$, two parents backcrossed with F$_1$, and F$_3$ lines derived from cross of above two lines were investigated for flowering type(mammoth gene) and flower color. All plants of F$_1$ population revealed normal flowering type and pink flower color. The progeny of F$_2$ generation was segregated into the phenotypic ratio of 9 : 3 : 3 : 1 with normal flowering type and pink flower color, normal and white, non flowering type(NF) and pink, and NF and white, respectively. Among the progenies of back-crossing populations, the flowering type showed a segregation ratio of 1 : 1 as normal and NF in BP$_1$ and flower color did also 1 : 1 as pink and white in BP$_2$. All lines have the mammoth gene in F$_3$. that were selected in F$_2$ progeny as non flowering. But 9 lines among 14 were segregated with 3 : 1 as pink and white flower in F$_3$. which were selected in F$_2$ as pink flower color. These results indicated that the characters of mammoth gene and white flower were controlled by a pair of recessive genes, respectively.

• 한국응용곤충학회지
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• 제21권2호
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• pp.68-72
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• 1982

인삼 재배포장에서 병원균인 Fusarium spp.의 밀도와 근부에 영향을 미치는 토양환경요인을 조사하였다. 2년근 포장의 토양을 토성별로 분류하여 결주율, Fusarium spp. 밀도, 화학적 성질을 비교해 본 결과 점토 함량이 들었고 결주율과 질산태 질소는 줄어드는 경향이었으며 다른 성질은 뚜렷한 차이가 없었다. 6년근 포장에서는 근부율과 유효인산 함량이 정의 상관(r=0.3162, p=0.05)을 보였으며 Fusarium spp. 밀도와 Streptomyces spp. 밀도는 고도의 부의 상관(r=-0.3976, p=0.01)을 나타내었다.