【摘要】 观测了枯草芽孢杆菌BS、GF1和荧光假单胞菌LX1、BCA1 4株生防菌对7株来源不同的辣椒疫病病菌的拮抗作用和防治效果。结果表明:BS对辣椒疫病病菌菌丝的拮抗作用显著高于其它3株生防菌,抑制率达到33.2%~59.4%;温室防病试验中,BS喷雾处理和BCA1灌根处理对辣椒疫病具有明显的防治效果,防效分别达到56.83%和57.81%。BS抗菌粗提物对病菌菌丝生长具有明显的抑制作用,抑菌作用与抗菌粗提物稀释倍数呈负相关,稀释10倍时抑制率达到100%。BS抗菌粗提物处理使辣椒疫病病菌菌丝分枝增多,分枝间距明显缩短,分枝顶端原生质消解;同时可以显著抑制辣椒疫病病菌游动孢子的萌发速度和萌发率。对绿色荧光蛋白标记的BS菌株(gfp-BS)在辣椒幼苗各部位定殖情况的检测表明:该菌可以通过种子细菌化成功定殖于辣椒植株体内,出苗60d后仍能检测到荧光标记的菌落,其定殖量维持在103cfu/g以上。更多还原

【Abstract】 The antagonism and control efficiency of four bacterial antagonists,including Bacillus subtilis BS,GF1,and Fluorescent pseudomonads LX1,BCA1,on seven strains of Phytophthora capsici from different origins were studied.Among the four bacterial antagonists tested,BS showed the maximum suppression of mycelial development of P.capsici.The inhibition rates ranged from 33.2% to 59.4%.In biological control assay in vivo,the most effective suppression of pepper Phytophthora blight was achieved when BS was sprayed or BCA1 was drenched on the plants.The control effects were 56.83% and 57.81%,respectively.The myce-lial growth was significantly suppressed by crude antibiotic extract of strain BS.The inhibition rate reached 100% when the mycelia were treated with 10-fold dilution of crude extract. Microscopic observation disclosed that hyphal branch of P.capsici increased,the interval between branches shortened remarkably,and the protoplasm on the apex of branch dissolved after treatment with extract.In addition,the zoospore germination was significantly inhibited by the extract.The colonization of BS in pepper seedlings was studied by a GFP-labeled BS strain.The results showed that BS could colonize in the roots,stems,and leaves of pepper seedlings by seed soaking with the bacteria.The GFP-labeled BS could be detected 60 d after the emergence and the colonized population maintained more than 103 cfu/g.更多还原