【作者】 常冬梅；

【导师】 尚庆茂；

【作者基本信息】 中国农业科学院 ， 蔬菜学， 2010， 硕士

【摘要】 针对我国蔬菜育苗基质微生物菌群结构不合理、生物学活性低的状况,本研究以“中椒6号”辣椒(Capsicum annuum L.)为试验材料,采用根际接种芽孢杆菌的方法进行人为调节,研究了芽孢杆菌对辣椒幼苗根际生物学活性的影响、对辣椒壮苗形成及产量品质的作用以及对辣椒猝倒病的防治作用及其机理,为改善育苗基质的生物学特性、构建良好的蔬菜育苗系统提供理论依据。1.采用注射法将2株芽孢杆菌(地衣芽孢杆菌、多粘芽孢杆菌)及3种微生物制剂(微生物综合调理剂、可溶性内生菌根促根剂、根系菌根菌促进剂)接种至辣椒幼苗根际后,芽孢杆菌较微生物制剂更早地表现出促生效果,定植时幼苗的壮苗指数、净光合速率、叶绿素含量和根系活力都显著高于对照(P<0.05),幼苗茎叶矿质元素(N、P、Ca、Mg、Fe)含量也有不同程度的提高,其中,铁含量分别提高了27.22%和59.17%;芽孢杆菌处理还降低了初花节位,并分别增产29.40%和33.24%,同时提高了果实总糖含量、糖酸比及维生素C含量,改善了果实品质。2.与不接种对照相比,芽孢杆菌及其制剂(地衣芽孢杆菌、多粘芽孢杆菌、微生物综合调理剂)显著增加了辣椒幼苗根际微生物生物量碳和呼吸强度,降低了微生物代谢熵;最大使根际脲酶、蔗糖酶和过氧化氢酶活性分别提高了18.08%、126.79%和9.35%;同时,接种芽孢杆菌还显著增加了根际速效磷和速效钾含量。3种芽孢杆菌,无论速效养分含量或酶活性,都是微生物综合调理剂作用最明显。3.平板对峙试验结果表明,5株芽孢杆菌(BS1.1216、BS1.933、YB40、YB43、YB54)对立枯丝核菌(Rhizoctonia solani Kühn)、瓜果腐霉(Pythium aphanidermatum)和刺腐霉(Pythium spinosum)的平板抑制率分别达到63.21%~67.46%、38.86%~47.78%和41.92%~55.02%;盆栽抑制试验中,5株芽孢杆菌对辣椒猝倒病表现出很好的防治效果,对瓜果腐霉和刺腐霉抑制效果最好的分别是BS1.933和BS1.1216。4.枯草芽孢杆菌BS1.933和BS1.1216能够在未播种基质及辣椒幼苗根际成功定殖并持续一定时间,且都随时间延长菌量下降。BS1.1216的成功定殖,使基质微生物活性显著提高,对由刺腐霉引起的辣椒猝倒病表现出很好的防治效果,使发病率降低了9.60%~33.29%,相对防效达到32.40%~77.67%,且随BS1.1216接种浓度升高效果愈发显著,BS1.1216处理还显著提高了辣椒幼苗的株高及子叶面积。更多还原

【Abstract】 According to the condition of unbalanced microflora and low microbial activity of soilless media,pepper (Capsicum annuum L. cv. Zhongjiao No.6) was selected as experimental material in this study to research the effects and mechanisms of inoculating Bacillus spp. in rhizosphere of seedlings on improving biological activities of rhizosphere,promoting pepper growth and development,fruit yield and quality,control efficiency to pepper damping-off. The aim was to improve biological characters of soilless media and to provide the theoretical basis of constructing well culture system of vegetable seedling.1. 2 strains of Bacillus spp.(Bacillus licheniformis and Bacillus polymyxa) and 3 kinds of microbial agents(MPX,ERS and MRS) were inoculated into soilless media by suspensions injection method. Bacillus spp. exerted promoting-growth effects earlier than microbial agents. Seedling index, net photosynthetic rate,chlorophyll content and root vigor increased distinctly compared to control seedlings (P<0.05). Contents of mineral elements such as N,P,Ca,Mg and Fe were raised in various degree within Bacillus spp. treated seedlings. Contents of Fe were raised by 27.22% and 59.17%. In contrast with non-inoculated control,Bacillus spp. inoculation lowered first flowering node and increased fruit yield by 29.40% and 33.24%. At the same time,total sugar,sugar-acid ratio and Vc of fruit were increased. Fruit quality was improved.2. Compared to non-inoculated control,Bacillus spp. and its microbial agents(Bacillus licheniformis,Bacillus polymyxa and MPX) significantly increased the microbial biomass carbon and respiratory intensity,reduced microbial metabolic quotient in rhizosphere of pepper seedlings. Urease,sucrase and catalase activity were greatest improved by 18.08%,126.79% and 9.35%,respectively. The treatments with Bacillus spp. inoculation obviously increased the contents of available N,P and K in rhizosphere of pepper seedlings. In regard to the available nutrient contents and enzyme activities, MPX obtained the best effect.3. 5 strains of Bacillus spp.(BS1.1216,BS1.933,YB40,YB43 and YB54)displayed a broad antifungal spectrum in dual cultures with pathogens. Inhibitory rates to Rhizoctonia solani Kühn,Pythium aphanidermatum and Pythium spinosum in plates were up to 63.21%~67.46% ,38.86%~47.78% and 41.92%~55.02%,respectively. Good control effect had achieved for Bacillus spp. to pepper damping-off caused by Pythium aphanidermatum and Pythium spinosum,BS1.933 and BS1.1216 had the best effect,respectively.4. Bacillus subtilis BS1.933 and BS1.1216 could colonize in soilless media without sowing and rhizosphere of pepper seedlings and maintain for some time. The live bacterial numbers declined with the time. Successful colonization of BS1.1216 made the microbial activity of soilless media raise significantly, incidence of damping-off reduce by 9.60%~33.29% , control efficacy be up to 32.40%~77.67%. The effectiveness went up with the initial inoculum densities. At the same time,the treatments with BS1.1216 inoculation obviously increased plant height and cotyledon size of pepper seedlings.更多还原