World Journal of Microbiology and Biotechnology

, 24:2499

Water-soluble granules containing Bacillus megaterium for biological control of rice sheath blight: formulation, bacterial viability and efficacy testing

Authors

  • Amornrat Chumthong
    • Department of Pharmaceutical Technology, Faculty of Pharmaceutical SciencesPrince of Songkla University
  • Mana Kanjanamaneesathian
    • Plant Production Technology Program, Faculty of Animal Sciences and Agricultural TechnologySilpakorn University
  • Ashara Pengnoo
    • Department of Earth Science, Faculty of Natural ResourcesPrince of Songkla University
    • Department of Pharmaceutical Technology, Faculty of Pharmaceutical SciencesPrince of Songkla University
Original Paper

DOI: 10.1007/s11274-008-9774-7

Cite this article as:
Chumthong, A., Kanjanamaneesathian, M., Pengnoo, A. et al. World J Microbiol Biotechnol (2008) 24: 2499. doi:10.1007/s11274-008-9774-7

Abstract

Endospores of B. megaterium were formulated in granule formulations with sodium alginate, lactose and polyvinylpyrrolidone (PVP K-30) by the wet granulation technique. The granule formulation exhibited good physical characteristics, such as high-water solubility and optimal viscosity, that would be suitable for spray application. The bacteria remained viable in the dry granule formulation at 109 c.f.u./g after 24 months storage at room temperature. Under laboratory conditions, aqueous solutions of the formulation showed high activity against mycelial growth of R. solani (99.64 ± 0.14% mycelial inhibition). High viability of the bacterial antagonist on leaf sheath and leaf blade at day 7 after spraying with the formulation was observed (approximately 106 c.f.u./g of plant). Application of an equivalent number of un-formulated endospores resulted in much loss of the bacterial endospores even 1 day after application. In a small pilot field study, an aqueous solution of the formulation (3%w/v) applied by spraying at days 1, 5 and 10 after pathogen inoculation of the rice plants was more effective in suppressing rice sheath blight disease than one application of a fungicide (Iprodione) at day 1. Additionally, rice plants sprayed with the aqueous solution of the granule formulation had higher panicle and whole kernel weights than those of fungicide-treated and control (untreated) plants.

Keywords

Bacillus megateriumBiological controlFormulationGranulesRhizoctonia solaniRiceSheath blight disease

Copyright information

© Springer Science+Business Media B.V. 2008