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.

토마토에 염류 내성을 유도하는 바실러스 균주 처리 후 근권 미생물 군집 구조 연구

유성제,이신애,원항연,송재경,상미경,Yoo, Sung-Je,Lee, Shin Ae,Weon, Hang-Yeon,Song, Jaekyeong,Sang, Mee Kyung 한국환경농학회 2021 한국환경농학회지 Vol.40 No.1

BACKGROUND: Soil salinity causes reduction of crop productivity. Rhizosphere microbes have metabolic capabilities and ability to adaptation of plants to biotic and abiotic stresses. Plant growth-promoting bacteria (PGPB) could play a role as elicitors for inducing tolerance to stresses in plants by affecting resident microorganism in soil. This study was conducted to demonstrate the effect of selected strains on rhizosphere microbial community under salinity stress. METHODS AND RESULTS: The experiments were conducted in tomato plants in pots containing field soil. Bacterial suspension was inoculated into three-week-old tomato plants, one week after inoculation, and -1,000 kPa-balanced salinity stress was imposed. The physiological and biochemical attributes of plant under salt stress were monitored by evaluating pigment, malondialdehyde (MDA), proline, soil pH, electrical conductivity (EC) and ion concentrations. To demonstrate the effect of selected Bacillus strains on rhizosphere microbial community, soil microbial diversity and abundance were evaluated with Illumina MiSeq sequencing, and primer sets of 341F/805R and ITS3/ITS4 were used for bacterial and fungal communities, respectively. As a result, when the bacterial strains were inoculated and then salinity stress was imposed, the inoculation decreases the stress susceptibility including reduction in lipid peroxidation, enhanced pigmentation and proline accumulation which subsequently resulted in better plant growth. However, bacterial inoculations did not affect diversity (observed OTUs, ACE, Chao1 and Shannon) and structure (principle coordinate analysis) of microbial communities under salinity stress. Furthermore, relative abundance in microbial communities had no significant difference between bacterial treated- and untreated-soils under salinity stress. CONCLUSION: Inoculation of Bacillus strains could affect plant responses and soil pH of tomato plants under salinity stress, whereas microbial diversity and abundance had no significant difference by the bacterial treatments. These findings demonstrated that Bacillus strains could alleviate plant's salinity damages by regulating pigments, proline, and MDA contents without significant changes of microbial community in tomato plants, and can be used as effective biostimulators against salinity stress for sustainable agriculture.

고추 식물의 건조 스트레스 완화를 위한 미생물 선발

김상태(Sang Tae Kim),유성제(Sung-Je Yoo),송재경(Jaekyeong Song),원항연(Hang-Yeon Weon),상미경(Mee Kyung Sang) 한국식물병리학회 2019 식물병연구 Vol.25 No.3

Drought stress is considered as one of major abiotic stresses; it leads to reduce plant growth and crop productivity. In this study, we selected bacterial strains for alleviating drought stress in chili pepper plants. As drought-tolerant bacteria, 28 among 447 strains were pre-selected by in vitro assays including growth in drought condition with polyethylene glycol and plant growth-promoting traits including production of 1-aminocyclopropane-1-carboxylate deaminase, indole-3-acetic acid and exopolysaccharide. Sequentially, 7 among pre-selected 28 strains were screened based on relative water content (RWC); GLC02 and KJ40, among seven strains were finally selected by RWC and malondialdehyde (MDA) in planta trials under an artificial drought condition by polyethylene glycol solution. Two strains GLC02 and KJ40 reduced drought stress in a natural drought condition as well as an artificial condition. Strains GLC02 or KJ40 increased shoot fresh weight, chlorophyll and stomatal conductance while they decreased MDA in chili pepper plants under a natural drought condition. However, two strains did not show biocontrol activity against diseases caused by Phytophthora capsici and Xanthomonas campestris pv. vesicatoria in chili pepper plants. Taken together, strains GLC02 or KJ40 can be used as bio-fertilizer for alleviation of drought stress in chili pepper plants.

Trichoderma sp. GL02에 의한 고추 식물의 건조 스트레스 완화 효과

김상태 ( Kim Sang Tae ),유성제 ( Yoo Sung-je ),송재경 ( Song Jaekyeong ),원항연 ( Weon Hang-yeon ),상미경 ( Sang Mee Kyung ) 한국유기농업학회 2020 韓國有機農業學會誌 Vol.28 No.3

Drought stress is one of major environmental stresses in plants; this leads to reduce plant growth and crop yield. In this study, we selected fungal isolate for mitigating drought stress in pepper plants. To do this, 41 fungi were isolated from rhizosphere or bulk soils of various plants in Jeju, Gangneung, Hampyeong in Korea. Out of 41 isolates, we screened two isolates without phytotoxicity through seed germination of tomato, pepper, and cabbage treated with fungal spores; through following plant assay, we selected GL02 as a candidate for alleviating drought stress in pepper plants. As a result of greenhouse test of pepper plants in drought condition, the stomatal conductance on leaves of pepper plants treated with GL02 was increased, whereras the malondialdehyde (MDA) and electrolyte leakage were decreased compared to that in control plants. When stressed plants were rewatered, stomatal conductance of the plants treated with GL02 was increased; the electrolyte leakage was decreased. Based on internal transcribed spacer (ITS) sequencing analysis, isolate GL02 was belonging to genus Trichoderma. Taken together, drought stress in pepper plants treated with GL02 was alleviated, when it was rewatered after drought-stressed, the plants could be recovered effectively. Therefore, Trichoderma sp. GL02 could be used as a bio-fertilizer to alleviate drought stress in pepper plants.