Decreased incidence of disease caused by Sclerotinia sclerotiorum and improved plant vigor of oilseed rape with Bacillus subtilis Tu-100

Key Laboratory for Genetic Improvement of Oil Crops, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, 430062, People's Republic of China.
Applied Microbiology and Biotechnology (Impact Factor: 3.34). 11/2005; 68(6):802-7. DOI: 10.1007/s00253-005-1938-x
Source: PubMed


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.

Download full-text


Available from: Daniel P Roberts, Mar 26, 2014
32 Reads
  • Source
    • "Agricultural Culture Collection of China (Beijing, China) as ACCC 05745. Another strain, B. megaterium ACCC 10407 is a known phosphate-solubilizing bacterium (Zhong and Huang 2005 "
    [Show abstract] [Hide abstract]
    ABSTRACT: Sustainable methods with diminished impact on the environment need to be developed for the production of oilseed rape in China and other regions of the world. A biological fertilizer consisting of Bacillus megaterium A6 cultured on oilseed rape meal improved oilseed rape seed yield (P < 0.0001) relative to the nontreated control in 2 greenhouse pot experiments using natural soil. This treatment resulted in slightly greater yield than oilseed rape meal without strain A6 in 1 of 2 experiments, suggesting a role for strain A6 in improving yield. Strain A6 was capable of solubilizing phosphorus from rock phosphate in liquid culture and produced enzymes capable of mineralizing organic phosphorus (acid phosphatase, phytase) in liquid culture and in the biological fertilizer. The biologically based fertilizer, containing strain A6, improved plant phosphorus nutrition in greenhouse pot experiments resulting in significantly greater available phosphorus in natural soil and in significantly greater plant phosphorus content relative to the nontreated control. Seed yield and available phosphorus in natural soil were significantly greater with a synthetic chemical fertilizer treatment, reduced in phosphorus content, than the biological fertilizer treatment, but a treatment containing the biological fertilizer combined with the synthetic fertilizer provided the significantly greatest seed yield, available phosphorus in natural soil, and plant phosphorus content. These results suggest that the biological fertilizer was capable of improving oilseed rape seed yield, at least in part, through the phosphorus-solubilizing activity of B. megaterium A6.
    Canadian Journal of Microbiology 04/2013; 59(4):231-6. DOI:10.1139/cjm-2012-0579 · 1.22 Impact Factor
  • Source
    • "Suppression of S. sclerotiorum on oilseed rape and promotion of plant growth with two formulations of B. subtilis strains BY-2 and Tu- 100 in the field Bacillus subtilis BY-2 was evaluated in field trials conducted at separate locations when delivered in the pellet and in the wrap seed treatment formulations alone, in a spray application alone, and in these seed treatment formulations combined with the spray application (Table 2). This strain was compared to a second B. subtilis isolate, Tu-100, which had previously been shown to control S. sclerotiorum on oilseed rape (Hu et al., 2005, 2011) and carbendazim , the standard chemical control method for this pathogen on oilseed rape in this region of China. At the Wuxue site, where the pellet formulation was evaluated, all three BY-2 treatments provided disease control that were similar with each other, similar to all three Tu-100 treatments, similar to the chemical control treatment, and significantly greater than the pellet and non-treated control treatments. "
    [Show abstract] [Hide abstract]
    ABSTRACT: We are developing a collection of Bacillus strains, isolated from different environments, for use in controlling Sclerotinia sclerotiorum on oilseed rape in China and elsewhere. Strain BY-2, isolated from internal tissues of an oilseed rape root, was demonstrated to be Bacillus subtilis based on biochemical and morphological characteristics and on 16S RNA gene sequence. Photographic evidence from gnotobiotic studies using the lacZ-tagged strain BY-2(pUC18) confirmed that this strain was capable of colonizing internal root tissues. Strain BY-2 did not effectively colonize the ectorhizosphere or the surface of the stems or leaves of oilseed rape when applied in pellet or wrap seed treatment formulations. Populations of BY-2 dropped from 108 CFU seed-1 to 104 CFU g root-1 and ⩽ 102 CFU g stem-1 or leaf-1 after 60 days. Strain BY-2 was applied as a pellet seed treatment formulation alone, as a spray at flowering alone, and as the pellet seed treatment formulation combined with the spray application in two field trials at the Wuxue location conducted in two consecutive years. These three treatments containing BY-2 provided disease control (disease incidence) and mean seed yield that was similar to the chemical control treatment and significantly greater than the pellet without bacteria and non-treated control treatments. All three of these BY-2 treatments were similar to each other with regard to these two metrics and to treatments containing B. subtilis Tu-100, a genetically distinct strain previously shown to be effective against this disease. In two additional field trials, conducted in consecutive years at the Wuhan location, strain BY-2 applied as a wrap seed treatment formulation alone, as a spray at flowering alone, and as the wrap seed treatment combined with the spray application provided disease control (disease incidence) and mean seed yield that was similar to the chemical control treatment. These three BY-2 treatments also were significantly greater than the non-treated control treatments and compared favorably to treatments containing Tu-100. There was no evidence of BY-2 promoting growth of oilseed rape when applied in the pellet or wrap seed treatment formulations in field trials conducted at the Wuxue or at the Wuhan locations. We now have three Bacillus strains (B. subtilis strains BY-2 and Tu-100, B. megaterium A6) that control S. sclerotiorum on oilseed rape in the field that can be tested in strain combinations for enhanced disease control. We also have multiple methods for application of Bacillus strains as both seed treatment and foliar applications were effective.
    Biological Control 01/2013; 70. DOI:10.1016/j.biocontrol.2013.12.005 · 1.64 Impact Factor
  • Source
    • "For antibiosis to be effective in this biocontrol interaction , Tu-100 must colonize the shoot so that any antibiotics produced in planta by Tu-100 are in close proximity to the invading pathogen. Colonization of oilseed rape roots has been studied and it was demonstrated that Tu-100 could become established within oilseed rape roots (Hu et al. 2005). However, experiments investigating epiphytic and endophytic colonization of oilseed rape shoots need to be performed before the role of antibiosis in this biological control interaction can be substantiated. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Sclerotinia sclerotiorum causes serious yield losses in crops in the People's Republic of China. Two formulations of oilseed rape seed containing the bacterium Bacillus subtilis Tu-100 were evaluated for suppression of this pathogen in field trials conducted at two independent locations. The pellet formulation significantly reduced disease (incidence and disease index) and increased plant dry mass, while the wrap formulation significantly reduced disease incidence and significantly increased plant dry mass at both field locations. Mean seed yield per 120 plants with both formulations of isolate Tu-100 was significantly greater than the appropriate controls, but at only one of the locations. Both formulations provided stable B. subtilis Tu-100 biomass (≥10(5) CFU·g(-1)) and seed germination (≥85%) over a 6 month period at room temperature. Polymerase chain reaction and DNA sequence analysis identified ituC and ituD, and bacAB and bacD in the genome of isolate Tu-100. These genes are involved in the biosynthesis of iturin and bacilysin. Iturin was detected in culture filtrates from isolate Tu-100, with thin layer chromatography. Detection of bacilysin was not attempted. Experiments reported here indicate the commercial viability of B. subtilis Tu-100 for suppression of S. sclerotiorum on oilseed rape.
    Canadian Journal of Microbiology 07/2011; 57(7):539-46. DOI:10.1139/w11-041 · 1.22 Impact Factor
Show more