辣椒内生菌BS-2在白菜体内的定殖、促生和防炭疽病作用

Colonization,promotion growth and biocontrol for anthracnose of endophytic bacterium BS-2 from Capsicum annuum in cabbage

辣椒体内的枯草芽孢杆菌BS-2菌株在白菜体内定殖、促生和防病作用表明:①用抗利福平标记BS-2r株浸种、浇灌土壤和涂抹叶片等方法接种,菌株均能进入白菜体内,并可在其全生育期内定殖;②菌液浸种24h后播种20天,其苗的鲜重比清水对照增加了91.20%～138.04%;③菌株对白菜炭疽病有较好的防治效果,但对不同时间接种病原菌的防治效果有所不同,以叶表面喷雾接种菌液后,立即接种病原菌的防效最好,其第3天和第6天的防效分别达95.12%和46.71%;而对接种菌液之前已接种病原菌的处理无防病效果.④菌株胞外分泌物对炭疽病菌菌丝生长、分生孢子产生与萌发均有很强的抑制作用.由此可见,来自辣椒体内的枯草芽孢杆菌BS-2 菌株不仅可在白菜体内定殖传导,而且对白菜有明显的促生作用,同时对炭疽病还有良好的防治作用.

The functions of endophytic bacterium BS-2(Bacillus subtilis endophyticus)isolatedfrom Capsicum annuum were investigated.The results showed that ① BS-2 which mutanted byantagonism against the rifampicin was able to colonize,propagate and move in cabbage plantsinoculated with seed dipping,root watering and leaf daubing;②cabbage seeds were dippedfirst for 24h then sowed in the soil and the fresh weight of cabbage plants was increased by91.20%-138.04% in 20d after the seeds sowed;③if the plants were inoculated with an-thracnose pathogen,Colletotrichum higginsianum,immediately after spraying BS-2 suspension,the best control effect was obtained,the effects in the third and sixth day were 95.12% and46.71% respectively;if the plants were inoculated with the pathogen 1d before spraying BS-2suspension,the control effect was not found;④the antibiotics secreted by BS-2 showed stronginhibitory activity against the pathogen's mycelial growth and conidia formation and germina-tion.All these suggested that the BS-2 strain could colonize in the cabbage plants,promotegrowth of cabbage,and control its anthracnose disease.