Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/18/2010
Publication Date: 8/14/2010
Citation: Dunlap, C.A., Schisler, D.A. 2010. Analysis of the surface properties of wheat spikelet components and their role in colonization by the biocontrol antagonist Cryptococcus flavescens OH 182.9 [abstract]. International Symposium on the Microbiology of Aerial Plant Surfaces. p. 36.
Technical Abstract: Cryptococcus flavescens OH 182.9 (NRRL Y-30216) is a biocontrol antagonist which has been shown to be effective in managing Fusarium head blight in wheat. Cryptococcus flavescens works by colonizing the wheat spikelet and competing with potential pathogens for the limited resources available. Knowledge of the parameters that influence microbial colonization of the wheat spikelet is important in developing successful control strategies. The surface of the aerial parts of wheat heads are covered by a waxy cuticle which mediates the interactions between the plant and the environment. The chemical and physical properties of the plant surface determine the nature of these interactions. The physicochemical surface properties of wheat spikelet components were determined using contact angle methods. The contact angles of several solvents were measured for the glumes and lemmas of two wheat cultivars. The results demonstrate that the surface chemistry and ultrastructure of glume and lemma tissues changes around the time of anthesis for both of the wheat cultivars tested with the structures reaching a minimum in hydrophobicity immediately after flowering. These results are reported in conjunction with microbial colonization data of C. flavescens to understand the role of the physiochemistry of infection court tissues in wheat-microbe-pathogen interactions on wheat heads. Further elucidating the nature of these interactions in the phyllosphere of wheat head tissues will lead to improved methods of controlling microbial pathogens such as the causal agent of Fusarium head blight of wheat.