枯草芽胞杆菌TR21叶腋喷施防治巴西蕉枯萎病

Bio-control Effect on Panama Disease of Banana Brazil(Musa spp.)by Spraying Bacillus subtilis Strain TR21 on the Axil

枯草芽孢杆菌TR21是一株植物内生菌,能够通过叶腋接种在香蕉体内定殖。采用叶腋接种法研究TR21对盆栽巴西蕉枯萎病的防治效果,并在大田采用随机区组试验设计,研究叶腋喷施TR21对巴西蕉枯萎病的防治效果和对巴西蕉挂果情况的影响。盆栽试验结果表明,按每次5.0×108 cfu/株的接种量,每隔10 d使用1次,连续使用4次,以地上部分萎蔫程度统计,30 d防效为(89.42±7.81)%,40 d防效为(85.95±2.77)%;结合地上部分萎蔫程度和球茎解剖结果统计,40 d防效为(79.32±4.49)%。从2008年4月至2009年2月进行田间试验,每次按1.8×108 cfu/株的用量,每隔10 d喷施1次,连续处理的植株到收获结束后,香蕉枯萎病发病率为(20.27±7.02)%,显著低于清水处理,防效达到61.92%。处理区2008年9月份的总挂果率达到25.00%,显著高于对照(3.13%),10月份的总挂果率为62.75%,高于对照(56.52%),但差异不显著。说明枯草芽孢杆菌TR21可以通过叶腋喷施接种防治巴西蕉枯萎病。

Bacillus subtilis strain TR21 is a plant endophyte which could colonize in banana plant by dropping in axil.The bio-control effect of this strain on Panama disease of Musa AAA Cavendish subgroup cv.Brazil was investigated in the greenhouse by dropping in axil and the effect on the fruit bearing ratio of banana was examined in fields by spraying TR21 strain on the axil with random block experimental design.The results of pot experiment demonstrated that with inoculation amount of 5.0×108 TR21 per plant and consecutively inoculate four times at intervals of 10 days,the disease control effect was evaluated from the wilt symptom of leaves.After 30 and 40 days,control effects were 89.42±7.81% and 85.95±2.77%,respectively.If the leave wilt symptom and corm brown stain symptom were taken into account,the disease control effect after 40 days was 89.42±7.81%.The field experiment was conducted from the April of 2008 to February of 2009.In the treatment blocks,the banana seedlings were spayed 1.8×108 TR21 cells per tree on the axil with an interval of 10 days.After all fruits were harvested,the disease incidence of treatments was 20.27±7.02%,which was significantly lower than the controls（53.23±1.49%）,and the control effect reached 61.92%.In September of 2008,the total fruit bearing ratio of treatments was 25.00%,which was significantly higher than controls（3.13%）,and in October of 2008,the fruits bearing ratio of treatments was 62.75%,and was still higher than the controls（56.52%）.These results suggested that the strain TR21 had the bio-control effect on Panama Disease by spraying its fermentation broth on the axil.