【摘要】 通过土豆培养基平板对峙试验,筛选出一株对草莓炭疽病病原有拮抗活性的木霉菌菌株Tr78。经液体发酵和剂型处理,制成含2×108个/g活孢子可湿性粉剂,对在露地和设施2种育苗方式下的草莓炭疽病进行田间药效测试,草莓测试品种为红颜。对病情指数和木霉菌孢子在草莓苗叶片和根表面定殖数的统计,是在对2种育苗方式草莓苗的第1次处理后的90 d(7月中旬)和110 d(8月上旬)进行的;死苗率的统计是在将2种育苗方式的草莓苗移栽到大棚后第30天进行的。结果表明:在2种育苗环境下,Tr78喷雾(T-1)和化学药剂喷雾(T-3)处理之间,草莓苗的病情指数和死苗率均无显著性差异,而它们的病情指数和死苗率分别显著性地(P≤0.05)低于清水喷雾(T-4)对照处理,但显著性地(P≤0.05)高于Tr78灌根+喷雾(T-2)处理。在防治效果方面,处理T-1和T-3之间也无显著性差异,但显著性地(P≤0.05)低于处理T-2,这与Tr78在草莓苗根表面(P≤0.01)的定殖数有显著的线性相关性,即Tr78在草莓苗根表面的定殖数越高,防治效果越好。总体来说,在大棚育苗环境下,经各项处理的草莓苗的病情指数和死苗率都明显低于它们各自在露地环境下的草莓苗。更多还原

【Abstract】 One Trichoderma spp.isolate Tr78 was selected by conducting an antagonistic screening test on petri dishes with potato dextrose agar(PDA),which showed antagonistic effect on suppressing the pathogen Colletotrichum gloeosporioides of strawberry seedling.A wettable powder(WP)formulation containing 2×108/g viable spores was made through the processes of liquid fermentation and formulation,which was then used for the field efficacy tests on preventing the disease under plastic-tunnel and open field conditions.The variety of tested strawberry was Hong Yan(Red Cheeks).The data of disease severity(DS)and the colony forming units(CFU)of Tr78 on the surface of the seedling leaves and roots were collected on the dates of 90(middle June)and 110(early August)respectively,after the seedlings were transplanted into the seedling beds under both cultivating conditions.The data of dead seedling(DSe)was collected 30 days after the seedlings were transplanted from both conditions into plastic-tunnel fields.The results indicated that there were no significant differences on DS and DSe between the treatments of Tr78 mist spray(T-1)and chemical spray(T-3).However,the parameters of DS and DSe of T-1 and T-3 were significantly(P≤0.05)lower than those in the treatment of water spray(T-4,control),but higher(P≤0.05)than those in the treatment of Tr78 root-drench + mist spray(T-2).There was no significant differences on the efficacy rate(%)of disease control(ERDC)between the treatments of T-1 and T-3,however,the parameters of the ERDC of T-1 and T-3 were significantly(P≤0.05)lower(P≤0.05)than those in T-2,which revealed a significant linear response with the inoculum levels of Tr78 on the surface of the seedling roots(P≤0.01),thus the more amount of the CFU of Tr78 colonized on the surface of the seedling roots,the better ERDC.In general,the parameters of DS and DSe in all treatments under plastic-tunnel condition were lower than those treatments under open field condition.更多还原