• Title/Summary/Keyword: antagonistic relationship

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Brief Introduction of Research Progresses in Control and Biocontrol of Clubroot Disease in China

  • He, Yueqiu;Wu, Yixin;He, Pengfei;Li, Xinyu
    • 한국균학회소식:학술대회논문집
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    • 2015.05a
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    • pp.45-46
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    • 2015
  • Clubroot disease of crucifers has occurred since 1957. It has spread to the whole China, especially in the southwest and nourtheast where it causes 30-80% loss in some fields. The disease has being expanded in the recent years as seeds are imported and the floating seedling system practices. For its effective control, the Ministry of Agriculture of China set up a program in 2010 and a research team led by Dr. Yueqiu HE, Yunnan Agricultural University. The team includes 20 main reseachers of 11 universities and 5 institutions. After 5 years, the team has made a lot of progresses in disease occurrence regulation, resources collection, resistance identification and breeding, biological agent exploration, formulation, chemicals evaluation, and control strategy. About 1200 collections of local and commercial crucifers were identified in the field and by artificiall inoculation in the laboratories, 10 resistant cultivars were breeded including 7 Chinese cabbages and 3 cabbages. More than 800 antagostic strains were isolated including bacteria, stretomyces and fungi. Around 100 chemicals were evaluated in the field and greenhouse based on its control effect, among them, 6 showed high control effect, especially fluazinam and cyazofamid could control about 80% the disease. However, fluzinam has negative effect on soil microbes. Clubroot disease could not be controlled by bioagents and chemicals once when the pathogen Plasmodiophora brassicae infected its hosts and set up the parasitic relationship. We found the earlier the pathogent infected its host, the severer the disease was. Therefore, early control was the most effective. For Chinese cabbage, all controlling measures should be taken in the early 30 days because the new infection could not cause severe symptom after 30 days of seeding. For example, a biocontrol agent, Bacillus subtilis Strain XF-1 could control the disease 70%-85% averagely when it mixed with seedling substrate and was drenching 3 times after transplanting, i.e. immediately, 7 days, 14 days. XF-1 has been deeply researched in control mechanisms, its genome, and development and application of biocontrol formulate. It could produce antagonistic protein, enzyme, antibiotics and IAA, which promoted rhizogenesis and growth. Its The genome was sequenced by Illumina/Solexa Genome Analyzer to assembled into 20 scaffolds then the gaps between scaffolds were filled by long fragment PCR amplification to obtain complet genmone with 4,061,186 bp in size. The whole genome was found to have 43.8% GC, 108 tandem repeats with an average of 2.65 copies and 84 transposons. The CDSs were predicted as 3,853 in which 112 CDSs were predicted to secondary metabolite biosynthesis, transport and catabolism. Among those, five NRPS/PKS giant gene clusters being responsible for the biosynthesis of polyketide (pksABCDEFHJLMNRS in size 72.9 kb), surfactin(srfABCD, 26.148 kb, bacilysin(bacABCDE 5.903 kb), bacillibactin(dhbABCEF, 11.774 kb) and fengycin(ppsABCDE, 37.799 kb) have high homolgous to fuction confirmed biosynthesis gene in other strain. Moreover, there are many of key regulatory genes for secondary metabolites from XF-1, such as comABPQKX Z, degQ, sfp, yczE, degU, ycxABCD and ywfG. were also predicted. Therefore, XF-1 has potential of biosynthesis for secondary metabolites surfactin, fengycin, bacillibactin, bacilysin and Bacillaene. Thirty two compounds were detected from cell extracts of XF-1 by MALDI-TOF-MS, including one Macrolactin (m/z 441.06), two fusaricidin (m/z 850.493 and 968.515), one circulocin (m/z 852.509), nine surfactin (m/z 1044.656~1102.652), five iturin (m/z 1096.631~1150.57) and forty fengycin (m/z 1449.79~1543.805). The top three compositions types (contening 56.67% of total extract) are surfactin, iturin and fengycin, in which the most abundant is the surfactin type composition 30.37% of total extract and in second place is the fengycin with 23.28% content with rich diversity of chemical structure, and the smallest one is the iturin with 3.02% content. Moreover, the same main compositions were detected in Bacillus sp.355 which is also a good effects biocontol bacterial for controlling the clubroot of crucifer. Wherefore those compounds surfactin, iturin and fengycin maybe the main active compositions of XF-1 against P. brassicae. Twenty one fengycin type compounds were evaluate by LC-ESI-MS/MS with antifungal activities, including fengycin A $C_{16{\sim}C19}$, fengycin B $C_{14{\sim}C17}$, fengycin C $C_{15{\sim}C18}$, fengycin D $C_{15{\sim}C18}$ and fengycin S $C_{15{\sim}C18}$. Furthermore, one novel compound was identified as Dehydroxyfengycin $C_{17}$ according its MS, 1D and 2D NMR spectral data, which molecular weight is 1488.8480 Da and formula $C_{75}H_{116}N_{12}O_{19}$. The fengycin type compounds (FTCPs $250{\mu}g/mL$) were used to treat the resting spores of P. brassicae ($10^7/mL$) by detecting leakage of the cytoplasm components and cell destruction. After 12 h treatment, the absorbencies at 260 nm (A260) and at 280 nm (A280) increased gradually to approaching the maximum of absorbance, accompanying the collapse of P. brassicae resting spores, and nearly no complete cells were observed at 24 h treatment. The results suggested that the cells could be lyzed by the FTCPs of XF-1, and the diversity of FTCPs was mainly attributed to a mechanism of clubroot disease biocontrol. In the five selected medium MOLP, PSA, LB, Landy and LD, the most suitable for growth of strain medium is MOLP, and the least for strains longevity is the Landy sucrose medium. However, the lipopeptide highest yield is in Landy sucrose medium. The lipopeptides in five medium were analyzed with HPLC, and the results showed that lipopeptides component were same, while their contents from B. subtilis XF-1 fermented in five medium were different. We found that it is the lipopeptides content but ingredients of XF-1 could be impacted by medium and lacking of nutrition seems promoting lipopeptides secretion from XF-1. The volatile components with inhibition fungal Cylindrocarpon spp. activity which were collect in sealed vesel were detected with metheds of HS-SPME-GC-MS in eight biocontrol Bacillus species and four positive mutant strains of XF-1 mutagenized with chemical mutagens, respectively. They have same main volatile components including pyrazine, aldehydes, oxazolidinone and sulfide which are composed of 91.62% in XF-1, in which, the most abundant is the pyrazine type composition with 47.03%, and in second place is the aldehydes with 23.84%, and the third place is oxazolidinone with 15.68%, and the smallest ones is the sulfide with 5.07%.

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A Transcendental Pragmatic Interpretation on the Notion of 'Injon' in Daesoon Thought (대순사상의 인존(人尊)에 대한 화용론적(話用論的) 해석)

  • Baek, Choon-hyoun
    • Journal of the Daesoon Academy of Sciences
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    • v.39
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    • pp.33-67
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    • 2021
  • This paper aims at revealing the core concept of Injon (Human Nobility). The concept of Injon is one of the salient fundamental ideas which makes Daesoon Jinrihoe recognizable as Daesoon Jinrihoe. The concept of Injon has the basic meaning of 'human nobility,' but within the context wherein the nobility of humankind is considered to be greater than the nobility of Heaven and Earth. Although the religious and ideological interpretations of Injon (human nobility) that have developed over time have been quite diverse and abundant, these interpretations are all limited in that they generally assume the relationship between 'Heaven and Earth' and 'Humanity' to be antagonistic. However, if human nobility is relativized in that manner, it can reduce the potential broader meanings of mutual beneficence and the earthly paradise of the later world. These interpretations are grounded in the view of semiotic interpretation. Such interpretations have composed their view point via the semiotic meaning of the words. The semiotic point of view suggests that meanings of words consist in the relation of the word and the object to which it denotes. We will introduce a new view point which can be termed the transcendental view point. This view focuses on how the exact interpretation of words and sentences depends on the comprehension of the triad of systematic relations among the word, object, and speaker. In the Daesoon Thought, the Former World is considered to be the world wherein all creations unfolded according to the principle of mutual contention. This led to the accumulation of grievances and grudges which condensed and filled the Three Realms of Heaven, Earth, and Humanity. The Former World was dominated by Western material civilization, selfishness, and exclusivism. It was also a world where humans suffered from various natural disasters such as floods, droughts, plagues, and wildfires. The Former World lost the constant Dao and was overwhelmed with all kinds of disasters and calamities. That world fell into various kinds of wretchedness. The causes which made the Former World so cruel came from humans misunderstanding their relation to nature and life in general; including human life. The anthropocentric modern cosmology insisted that the human race was the only one to have the powers and rights to exercise dominion over nature. On the other hand, there is the Later World, which means the ideal and perfect, immanent eternal world for all humankind in Daesoon Thought. This world consists of life, peace, and equality and is also characterized by three typical attributes: goodness, peace, and all kinds of life. All living beings previously struggled for survival, but in the Later World, those lifeforms will embrace each other; even across different realms. In Daesoon Thought, the world and cosmos contain diverse forms of life, and human have both an earthly life and life in the after world should they die before the Later World. There are also the lives of divine beings and animals, and other such living entities. Daesoon Thought subsumes pan-vitalism, which allows they acknowledgement of myriad possible lifeforms. The concept of the Later World in Daesoon Thought, which mainly revealed in The Canonical Scripture and the words of Sangje (Kang Jeungsan), suggests that all kinds of life, including humans, animals, and even spirits in the afterworld, can live together in a perfect coming earthly paradise which is immanent. The concept of Injon can be interpreted though the view of transcendental pragmatics as an alternative to the typical views discussed in Daesoon Thought. Thinkers should attempt to improve current discourse on Injon in Daesoon Thought by focusing on the point that all kinds the original teachings demonstrate a value of all lifeforms. Therein, Injon would indicate not only the human nobility and dignity but also the nobility and dignity of divine beings, divine humans, and all other forms of life that have existed across time. The dimension of time allows for recognition of lifeforms from the Former World, the afterworld, and the Later World. This revised appraisal of Injon could further accommodate denizens of the afterworld, animals, ghosts and spirits, the earth and cloud souls of humans, and other lifeforms held to exist in the cosmology of Daesoon Thought.