Hu Xiaojia, Roberts Daniel P, Jiang Mulan, Zhang Yinbo
Key Laboratory for Genetic Improvement of Oil Crops, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, 430062, People's Republic of China.
Appl Microbiol Biotechnol. 2005 Oct;68(6):802-7. doi: 10.1007/s00253-005-1938-x. Epub 2005 Oct 13.
Sclerotinia sclerotiorum causes serious yield losses in oilseed crops worldwide. Bacillus subtilis Tu-100 significantly reduced (P< or =0.05) the incidence of disease caused by S. sclerotiorum on oilseed rape at harvest in two trials conducted in fields artificially infested with this pathogen. Mean plant dry weight was significantly greater (P< or =0.05) and mean plant length was significantly greater (P< or =0.07) at the seven-true-leaf stage with the Tu-100 treatment than with the control. Mean seed yield per 120 plants at harvest was significantly greater (P< or =0.05) in the second field trial with treatments containing isolate Tu-100. B. subtilis Tu-100 also promoted the growth of hydroponically grown oilseed rape. Plants were approximately 15% greater in dry weight (P< or =0.0001) and 6% greater in length (P< or =0.0025) when grown in the presence of isolate Tu-100 in Hoagland's solution, compared with the noninoculated control. In gnotobiotic studies, the lacZ-tagged strain B. subtilis Tu-100(pUC18) was detected within all roots of oilseed rape. Isolate Tu-100 did not persist in the ectorhizosphere of oilseed rape. Populations of this isolate decreased from 8.5x10(8) colony-forming units (CFU) per seed to approximately 10(2) CFU in the plant ectorhizosphere within 30 days of sowing in autoclaved soil.
核盘菌在全球范围内导致油料作物严重减产。在两块人工接种该病原菌的田间试验中，枯草芽孢杆菌Tu-100显著降低了（P≤0.05）收获时油菜上由核盘菌引起的病害发生率。在七叶期，Tu-100处理组的植株平均干重显著高于（P≤0.05）对照组，植株平均长度也显著高于（P≤0.07）对照组。在第二项田间试验中，含有分离株Tu-100的处理组收获时每120株的平均种子产量显著高于（P≤0.05）对照组。枯草芽孢杆菌Tu-100还促进了水培油菜的生长。与未接种的对照组相比，在霍格兰氏溶液中添加分离株Tu-100培养的植株干重增加了约15%（P≤0.0001），长度增加了6%（P≤0.0025）。在无菌研究中，在油菜的所有根系中均检测到了携带lacZ标记的枯草芽孢杆菌Tu-100（pUC18）菌株。分离株Tu-100在油菜的根际周围不能持续存在。在高压灭菌土壤中播种后30天内，该分离株的数量从每粒种子8.5×10⁸个菌落形成单位（CFU）降至植株根际周围约10²CFU。
