Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: August 26, 2010
Publication Date: August 26, 2010
Citation: Behle, R.W., Compton, D.L., Laszlo, J.A. 2010. Using soyscreen in an oil-based biopesticide formulation to protect Beauveria bassiana Conidia from degradation by ultraviolet light energy [abstract]. American Chemical Society. Publication No. CHAS-35. Technical Abstract: Improving the efficacy of biological control treatments for pest control in crops will help to reduce dependence on chemical pesticide applications. Although effective for controlling insects, entomopathogenic microbes degrade rapidly when applied to field crops because of the adverse effects of sunlight exposure. Developing biopesticide formulations to protect the microbes from this exposure will extend the residual activity, improve efficacy of the treatment, and increase the potential for commercial development and consumer use. Feruloylated soy glycerides, referred to as soyscreen oil, are bio-based UV-absorbing molecules made by combining molecules of soybean oil with ferulic acid. Conidia of the entomopathogenic fungus, Beauveria bassiana, are hydrophobic and well suited for oil-based formulations. Experiments with soyscreen as a formulation ingredient with fungal conidia demonstrated two benefits. The first was that soyscreen had no detrimental effects on viability of conidia stored in the oil for 28 weeks. Second, soyscreen successfully protected conidia from degradation when exposed to artificial (xenon) and natural sunlight. However, these benefits did not translate to longer residual activity when applied to field grown plants [cabbage (Brassica oleracae L.) and beans (Phaseolis vulgaris L.)]. We subsequently demonstrated that the oils were absorbed by the plants leaving the fungal spores exposed to degradation by sunlight. Additional formulation techniques will be necessary to prevent the protective oil from being absorbed by the plants.