CAJ | 학술논문

为了明确 surfactin 产量不同的芽孢杆菌对黄瓜枯萎病的控制作用，本研究采用 N+注入诱变共获得1250株芽孢杆菌B006的突变株，通过对黄单孢杆菌的抑菌试验筛选并获得3株产surfactin突变株B841、B73和B1020。对各突变株NB发酵液的HPLC?ESI?MS分析表明：突变株B841和B73的surfactin含量比野生菌株B006分别升高了15.9%和14.8%，而突变株B1020的surfactin含量比野生菌株降低了85.2%；各突变株fengycin产量未发生改变。对surfactin各组分的质谱图解析，发现突变株B841和B1020的surfactin组分发生变化，突变株B841的surfactin组分中无m/z为995的同系物，而突变株B1020的MS图谱中只发现了m/z为1037和1051的surfactin同系物；对突变株的生物学特性测定表明：突变株B73和B1020的菌落形态发生改变，生长周期缩短；3个突变株比野生菌株产芽孢能力下降，突变株B1020在含有玉米粉和豆饼粉的培养基上不产生芽孢。对各菌株添加到育苗基质中（浓度为106 cfu·g?1）后，防治黄瓜枯萎病的效果测定表明：2周时，突变株B1020防效接近于野生菌株B006，达70%以上；但3周时，防效下降到36.2%；突变株B841防效始终低于野生菌株B006，只有29.1%。本研究发现芽孢杆菌B006及其突变株在NA培养液中的surfactin产量的高低与其在育苗基质中的防病效果无直接的相关性，对其在自然土中的防病效果值得进一步研究。
위료명학 surfactin 산량불동적아포간균대황과고위병적공제작용，본연구채용 N+주입유변공획득1250주아포간균B006적돌변주，통과대황단포간균적억균시험사선병획득3주산surfactin돌변주B841、B73화B1020。대각돌변주NB발효액적HPLC?ESI?MS분석표명：돌변주B841화B73적surfactin함량비야생균주B006분별승고료15.9%화14.8%，이돌변주B1020적surfactin함량비야생균주강저료85.2%；각돌변주fengycin산량미발생개변。대surfactin각조분적질보도해석，발현돌변주B841화B1020적surfactin조분발생변화，돌변주B841적surfactin조분중무m/z위995적동계물，이돌변주B1020적MS도보중지발현료m/z위1037화1051적surfactin동계물；대돌변주적생물학특성측정표명：돌변주B73화B1020적균락형태발생개변，생장주기축단；3개돌변주비야생균주산아포능력하강，돌변주B1020재함유옥미분화두병분적배양기상불산생아포。대각균주첨가도육묘기질중（농도위106 cfu·g?1）후，방치황과고위병적효과측정표명：2주시，돌변주B1020방효접근우야생균주B006，체70%이상；단3주시，방효하강도36.2%；돌변주B841방효시종저우야생균주B006，지유29.1%。본연구발현아포간균B006급기돌변주재NA배양액중적surfactin산량적고저여기재육묘기질중적방병효과무직접적상관성，대기재자연토중적방병효과치득진일보연구。
B. subtilis B006 could effectively suppress cucumber wilt caused by Fusarium oxysporum f. sp. cucumerinum. In order to understand the suppressing ability of Bacillus strain B006 and its surfactin-mutants against cucumber wilt disease, we implanted strain B006 by nitrogen ions. Mutants B841, B73 and B1020 were selected from 1250 implanted strains. Surfactin analysis with HPLC-ESI-MS showed that surfactin amount excreted by strain B841 and B73 in nutrient broth increased by 15.9%and 14.8%respectively, in comparison with their parental strain B006, while that from strain B1020 decreased by 85.2%. Amounts of fengycin produced by the three mutants were similar with strain B006. Mass spectrum analysis of surfactin showed that its constitution changed, as indicated by absence of m/z at 995 from B841and only m/z at 1037 and 1051 were detected from mutant B1020, in comparison with the mass spectrum of B006 with m/z at 995, 1009, 1023, 1037 and 1051. Determination of biological characteristics of the mutants indicated that colony appearance of mutant B73 and B1020 changed and their growth period shortened, and spore-forming rates reduced on NA and a spore-forming medium consisted of corn and soybean cake powders. Mutant B1020 couldn’t produce endospores on the spore-forming medium. The control efficacy of the mutants were tested in greenhouse by mixing the cell suspension with substrate at 106 cfu·g-1. Mutant B1020 could suppress cucumber wilt disease effectively similar with B006 at 2 weeks, with the control efficacy over 70%, but at 3 weeks with a lower efficacy of 36.2%. Mutant B841 didn’t show good suppressing ability, the control efficacy was only 29.1%at 3 weeks. The results indicated that the amounts of surfactin produced in nutrient broth by Bacillus strains was not positive to their control efficacies against cucumber Fusarium wilt in nursery substrate. Further study will be conducted in natural soil.