Bacillus sp. JJ2-01과 마늘 오일 혼합처리에 의한고추 흰비단병 억제 효과

상미경,문혜정,주호종,안성호,송재경 한국유기농업학회 2022 韓國有機農業學會誌 Vol.30 No.3

Southern blight caused by Sclerotium rolfsii is a serious soilborne disease in economically important crops including pepper. In this study, we conducted a selection of antagonistic bacterial strains and organic materials to biologically control the disease. Out of 39 strains isolated from soils at Jinju in Korea, strain JJ2-01 showed the highest mycelial growth inhibition; garlic oil among various organic materials significantly reduced disease incidence and severity. When a combination of strain JJ2-01 and garlic oil, or each was drenched into the pepper plants, combined treatment and garlic oil significantly suppressed the disease development, however, acid phosphatase activity in garlic oil-treated plants decreased. In the case of combined treatment, the soil activities did not affect by treatment, while soil urease activity was significantly increased by the combined treatment. Therefore, given soil quality and health for sustainable agriculture, the combination of strain JJ2-01 and garlic acid was an effective application for environmental- friendly control of Southern blight in pepper plants.

Influence of Commercial Antibiotics on Biocontrol of Soft Rot and Plant Growth Promotion in Chinese Cabbages by Bacillus vallismortis EXTN-1 and BS07M

상미경,Swarnalee Dutta,박경석 한국식물병리학회 2015 식물병연구 Vol.21 No.4

We investigated influence of three commercial antibiotics viz., oxolinic acid, streptomycin, and validamycin A, on biocontrol and plant growth promoting activities of Bacillus vallismortis EXTN-1 and BS07M in Chinese cabbage. Plants were pre-drenched with these strains followed by antibiotics application at recommended and ten-fold diluted concentration to test the effect on biocontrol ability against soft rot caused by Pectobacterium carotovorum SCC1. The viability of the two biocontrol strains and bacterial pathogen SCC1 was significantly reduced by oxolinic acid and streptomycin in vitro assay, but not by validamycin A. In plant trials, strains EXTN- 1 and BS07M controlled soft rot in Chinese cabbage, and there was a significant difference in disease severity when the antibiotics were applied to the plants drenched with the two biocontrol agents. Additional foliar applications of oxolinic acid and streptomycin reduced the disease irrespective of pre-drench treatment of the PGPRs. However, when the plants were pre-drenched with EXTN-1 followed by spray of validamycin A at recommended concentration, soft rot significantly reduced compared to untreated control. Similarly, strains EXTN-1 and BS07M significantly enhanced plant growth, but it did not show synergistic effect with additional spray of antibiotics. Populations of the EXTN-1 or BS07M in the rhizosphere of plants sprayed with antibiotics were significantly affected as compared to control. Taken together, our results suggest that the three antibiotics used for soft rot control in Chinese cabbage could affect bacterial mediated biocontrol and plant growth promoting activities. Therefore, combined treatment of the PGPRs and the commercial antibiotics should be carefully applied to sustain environmental friendly disease management.

Root-Dipping Application of Antagonistic Rhizobacteria for the Control of Phytophthora Blight of Pepper Under Field Conditions

상미경,Ji Yeon Oh,김기덕 한국식물병리학회 2007 Plant Pathology Journal Vol.23 No.2

This study was to examine the efficacy of a root-dipping application of antagonistic bacterial strains for the control of Phytophthora blight of pepper caused by P. capcisi, and to evaluate their plant growth-promoting effects in the field in 2005 and 2006. The candidate antagonistic rhizobacterial strains CCR04, CCR80, GSE09, ISE13, and ISE14 were treated by dipping plant roots with bacterial suspensions prior to transplanting. The candidate rhizobacterial strains CCR04, CCR80, GSE09, and ISE14 significantly (P = 0.05) reduced the disease incidence and the area under the disease progress curves when compared to buffer-treated controls in at least a year test. The metalaxyl (fungicide- treated control) resulted in one of the lowest disease incidences among the treatments in both years. Moreover, the strains CCR04, CCR80, GSE09, and ISE13 significantly (P = 0.05) increased the fruit weights and/or numbers of peppers in at least a year test compared to the buffer-treated controls. These results suggest that the antagonistic rhizobacterial strains CCR04, CCR80, and GSE09 could be efficient biocontrol agents by controlling Phytophthora blight of pepper and promoting the plant growth when treated with rootdipping at transplanting.

Biocontrol of Phytophthora Blight and Anthracnose in Pepper by Sequentially Selected Antagonistic Rhizobacteria against Phytophthora capsici

상미경,김기덕,김두연,박경석,박준호,Anupama Shrestha 한국식물병리학회 2013 Plant Pathology Journal Vol.29 No.2

We previously developed a sequential screening procedure to select antagonistic bacterial strains against Phytophthora capsici in pepper plants. In this study, we used a modified screening procedure to select effective biocontrol strains against P. capsici; we evaluated the effect of selected strains on Phytophthora blight and anthracnose occurrence and fruit yield in pepper plants under field and plastic house conditions from 2007 to 2009. We selected four potential biocontrol strains (Pseudomonas otitidis YJR27, P. putida YJR92, Tsukamurella tyrosinosolvens YJR102, and Novosphingobium capsulatum YJR107) among 239 bacterial strains. In the 3-year field tests, all the selected strains significantly (P < 0.05) reduced Phytophthora blight without influencing rhizosphere microbial populations; they showed similar or better levels of disease suppressions than in metalaxyl treatment in the 2007 and 2009 tests, but not in the 2008 test. In the 2-year plastic house tests, all the selected strains significantly (P < 0.05) reduced anthracnose incidence in at least one of the test years, but their biocontrol activities were variable. In addition, strains YJR27, YJR92, and YJR102, in certain harvests,increased pepper fruit numbers in field tests and red fruit weights in plastic house tests. Taken together, these results indicate that the screening procedure is rapid and reliable for the selection of potential biocontrol strains against P. capsici in pepper plants. In addition,these selected strains exhibited biocontrol activities against anthracnose, and some of the strains showed plant growth-promotion activities on pepper fruit.

Characterization of Bacillus luciferensis Strain KJ2C12 from Pepper Root, a Biocontrol Agent of Phytophthora Blight of Pepper

김해숙,상미경,명인식,천세철,김기덕 한국식물병리학회 2009 Plant Pathology Journal Vol.25 No.1

In this study, we characterized the bacterial strain KJ2C12 in relation with its biocontrol activity against Phytophthora capsici on pepper, and identified this strain using morphological, physiological, biochemical, fatty acid methyl ester, and 16S rRNA gene sequence analyses. Strain KJ2C12 significantly (P=0.05) reduced both final disease severity and areas under the disease progress curves of 5-week-old pepper plants inoculated with P. capsici compared to buffer-treated controls. As for the production of antibiotics, biofilms, biosurfactant, extracellular enzyme, HCN, and swarming activity, strain KJ2C12 produced an extracellular enzyme with protease activity, but no other productions or swarming activity. However, Escherichia coli produced weak biofilm only. Strain KJ2C12 could colonize pepper roots more effectively in a gnotobiotic system using sterile quartz sand compared to E. coli over 4 weeks after treatments. However, no bacterial populations were detected in 10 mM MgSO4 buffer-treated controls. Strain KJ2C12 produced significantly higher microbial activity than the MgSO4-treated control or E. coli over 4 weeks after treatments. Bacterial strain KJ2C12 was identified as Bacillus luciferensis based on morphological, physiological, and biochemical characteristics as well as FAME and 16S rRNA gene sequence analyses. In addition, these results suggested that B. luciferensis strain KJ2C12 could reduce Phytophthora blight of pepper by protecting infection courts through enhanced effective root colonization with protease production and an increase of soil microbial activity.

Microbial Population, Aflatoxin Contamination and Predominant Aspergillus Species in Korean Stored Rice

오지연,상미경,이호정,류문일,김기덕,오지은 한국식물병리학회 2010 Plant Pathology Journal Vol.26 No.2

We evaluated microbial populations and aflatoxin production in unhulled and white rice from rice processing complexes of the National Agricultural Cooperative Federation in five regions in Korea and identified three predominant Aspergillus species. Fungal and bacterial populations in rice samples were significantly different between regions in 2007. Aflatoxins were also detected and varied at the levels of 2.45 - 3.43 ng per g unhulled rice grain and 1.29 - 2.09 ng per g white rice grain. Unhulled rice generally detected higher level of aflatoxins than white rice regardless of sampling regions;however, no significant differences were found in Anseong and Cheonan in 2005 and Cheonan and Gimpo in 2007. Aflatoxin production between sampling regions was not different regardless of rice type and sampling year. Although the fungal diversity was highly distinct from region to region, three Aspergillus isolates were predominant in the rice samples; thus, representative isolates AC317, AF57, and AF8 were selected and identified based on their morphological and molecular characteristics. Consequently, isolates AC317, AF57,and AF8 were identified as A. candidus, A. flavus, and A. fumigatus, respectively. These fungi can produce mycotoxins that are harmful for consumers and thus it is important to detect and reduce the population of storage fungi in rice.

Peribacillus butanolivorans KJ40, Bacillus zanthoxyli HS1, B. siamensis H30-3와 Pseudomonas sp. BC42에 의한 오이 탄저병, 박과 류 과실썩음병과 오이 덩굴쪼김병의 생물방제 효과검정

김지원,상미경 한국식물병리학회 2023 식물병연구 Vol.29 No.2

Abiotic and biotic stresses have been a serious threat to crop growth and productivity in the agricultural system. In this study, four strains (HS1, H30-3, KJ40, and BC42), which have biological activities related to disease suppression or alleviation of salinity and drought stresses, were tested for broad-spectrum biocontrol activity against anthracnose caused by Colletotrichum orbiculare, a bacterial fruit blotch caused by Acidovorax citrulli, and Fusarium wilt caused by Fusarium oxysporum in cucumber plants. As a result of test, when the four strains were drenched into the soil, anthracnose in cucumber leaves significantly decrease; strain KJ40 suppressed disease incidence by A. citrulli; strain BC42 significantly reduced bacterial fruit blotch and Fusarium wilt compared to control. Therefore, strain KJ40 could be a biocontrol candidate for controlling anthracnose through induced systemic resistance and the disease caused by A. citrulli as well as alleviating drought stress; strain BC42 has broad-spectrum biocontrol activity against anthracnose, Fusarium wilt, and bacterial fruit blotch.

Amelioration of non-irrigated stress and improvement of sweet pumpkin fruit quality by Kushneria konosiri endophytic bacteria

김상태,상미경 한국환경생물학회 2023 환경생물 : 환경생물학회지 Vol.41 No.4

This study examined the impact of two bacterial strains, H05E-12 and H05R-04, on alleviating non-irrigation-induced stress and its subsequent effects on the fruit productivity of sweet pumpkin plants. When subjected to non-irrigation-induced stress, the lipid peroxidation, proline, total phenol, and total soluble sugar content significantly decreased in plants treated with either H05E-12 or H05R-04 compared to the control. In a greenhouse experiment under non-irrigated conditions, H05E-12-treated plants exhibited higher stomatal conductance than the control, although there was no significant change in the soil plant analysis development (SPAD) value due to treatment. Upon re-watering, an increase in fruit diameter was observed in H05E-12-treated plants, and the L-ascorbic acid content in the fruit also showed a significant increase compared to the control. The H05E-12 strain was identified as Kushneria konosiri. To the best of our knowledge, this is the first report detailing the beneficial effects of K. konosiri on the alleviation of non-irrigation-induced stress and the promotion of plant growth in sweet pumpkin plants.

근권미생물에 의한 식물의 생물·환경적 복합 스트레스 내성 유도

유성제,상미경,Yoo, Sung-Je,Sang, Mee Kyung 한국식물병리학회 2017 식물병연구 Vol.23 No.2

식물은 재배기간 동안 세균, 진균, 바이러스 등의 생물 스트레스뿐만 아니라 고온, 염, 건조 등 다양한 환경 스트레스에도 노출되어 왔다. 최근에는 기후 이상현상으로 인하여 환경 스트레스의 빈도 및 강도가 불규칙적으로 증가하고 있으며 이로 인해 병원균의 생장과 영향도 변화하여 생물과 환경의 복합 스트레스가 식물 재배에 큰 영향을 주고 있다. 유용미생물을 이용한 식물의 저항성 유도는 다양한 생물과 환경 스트레스로부터 식물을 보호하는 데 도움을 주며, 이러한 스트레스에 대한 피해를 감소시킬 수 있는 가능성을 열어 주었다. 본 리뷰에서는 식물의 생물과 환경 스트레스에 대한 피해를 감소시키는 데 영향을 주는 미생물의 결정인자에 대해 기술하였으며 미생물 결정인자에 의해 유도되는 식물 신호전달 체계 변화에 대해 기술하였다. 또한 복합 스트레스 경감을 위한 미생물의 역할과 연구 방향에 대해 기술하였다. 이 리뷰를 통해 변화하는 환경에 대비하기 위해서 다양한 방안을 마련하고 있는 농민들에게 도움이 되기를 바라며, 실제 유용미생물 연구가 식물 재배 중 발생할 수 있는 다양한 스트레스에 따른 농가 피해를 감소시킬 효과적 대응 방안으로 이어지길 바란다. Recently, global warming and drastic climate change are the greatest threat to the world. The climate change can affect plant productivity by reducing plant adaptation to diverse environments including frequent high temperature; worsen drought condition and increased pathogen transmission and infection. Plants have to survive in this condition with a variety of biotic (pathogen/pest attack) and abiotic stress (salt, high/low temperature, drought). Plants can interact with beneficial microbes including plant growth-promoting rhizobacteria, which help plant mitigate biotic and abiotic stress. This overview presents that rhizobacteria plays an important role in induced systemic resistance (ISR) to biotic stress or induced systemic tolerance (IST) to abiotic stress condition; bacterial determinants related to ISR and/or IST. In addition, we describe effects of rhizobacteria on defense/tolerance related signal pathway in plants. We also review recent information including plant resistance or tolerance against multiple stresses ($biotic{\times}abiotic$). We desire that this review contribute to expand understanding and knowledge on the microbial application in a constantly varying agroecosystem, and suggest beneficial microbes as one of alternative environment-friendly application to alleviate multiple stresses.

Complete genome sequence of Pseudomonas moraviensis EFBE32, a biocontrol bacterium against pepper bacterial wilt

안주희,김송화,상미경,진용주,김다연,김상윤,송재경 한국미생물학회 2022 미생물학회지 Vol.58 No.4

Pseudomonas moraviensis strain EFBE32 is a biocontrol bacterium against bacterial wilt which is known as most destructive disease caused by Ralstonia solanacearum. Here, we report the whole genome sequence of P. moraviensis strain EFBE32. The sequence analysis revealed that P. moraviensis strain EFBE32 has a single 6,030,129 bps circular chromosome with a DNA G + C-content of 60.1%. This chromosome contains 5,239 coding sequences and 16 rRNA and 69 tRNA genes. In the result of sequence analysis, it is revealed that strain EFBE32 possessed genes coding the disease suppression related enzymes, acyl-homoserine lactone acylase (QuiP and PvdQ) which is known as quorum quenching enzyme, and hydrogen cyanide synthase (HcnA, B, and C).