Abstract
The major hurdle in the production of commercial biocontrol agents (BCAs) has been the lack of production of appropriate formulations. Of particular importance is the conservation of viability and ecological competence after application. With this in mind studies were conducted to develop formulations of P. anomala which would have these attributes. Cells were grown in molasses-based medium modified with proline to different water availability levels (0.98 and 0.96) which significantly increased (up to 50%) the content of trehalose and arabitol in the yeast cells during liquid broth fermentation. The use of isotonic solutions for harvesting the yeast cells further increased the endogenous content of these compatible solutes as well as glycerol. Fluidised bed drying of cells at 30–80°C was carried out for 10 and 20 min and showed that viability was significantly decreased at 70–80°C. A temperature of 50°C for 20 min was found to be best for viability (70%) and moisture content of <10%. Several additives for conservation of viability showed that cotton seed flour+skimmed milk was the best treatment when dried at 50°C. The biocontrol efficacy of formulated P. anomala cells was tested in laboratory scale studies and this showed that they inhibited growth of Penicillium verrucosum and reduce ochratoxin A production in moist wheat grain under some combinations of water availability. Physiologically modified formulated yeast cells with increased levels of trehalose and arabitol gave similar efficacy as fresh cells. This suggests that ecophysiological manipulation of such BCAs can result in improved ecological competence of such formulations and effective biocontrol.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.