Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/20/2006
Publication Date: 9/27/2006
Citation: Calderon, F.J., Acosta Martinez, V. 2006. Diffuse-Reflectance Mid-IR and NIR Spectroscopic Properties of Mycorrhizal and Non-mycorrhizal roots. Meeting Abstract. Federation of Analytical Chemistry and Spectroscopy (FACSS) National Meeting for the Society for Applied Spectroscopy. Sept. 24-28, 2006. Lake Buena Vista, FL.
Technical Abstract: Quantification of mycorrhizae by traditional methods is slow and prone to observer bias. A quick spectroscopic method would allow for the identification of mycorrhizal roots of large sample sets. In this experiment, we measured the diffuse-reflectance Fourier-Transformed Mid-IR and NIR spectral properties of crop roots infected with symbiotic mycorrhizal fungi, as well as and non-mycorrhizal control roots. Corn, sorghum, sunflower, and wheat plants were grown in the greenhouse on heat treated soil with and without mycorrhizal inoculum. The plants were harvested after six weeks, then the roots were rinsed, lyophilized and ground for scanning with the diffuse reflectance FT-IR. Root samples were also analyzed for fatty acid content in order to quantify mycorrhizal markers. The data shows that mycorrhizal corn roots had more 16:1 w5c, 18:2w6, and/or 18:1 w9c fungal markers than non-mycorrhizal roots, confirming mycorrhizal infection. Principal Components Analysis of the Mid-IR spectra show grouping according to mycorrhizal or non-mycorrhizal roots in Sorghum, while the NIR region was useful to separate mycorrhizal and non-mycorrhizal corn roots. Preliminary PCA results with sunflower spectra did not show a grouping pattern.