Monitoring Respiration Inhibition In Turfgrass Using FTIR Analysis Of Whole Leaves.

The rapid measurement of mitochondrial respiration, a key metabolic pathway in plants, is essential to turfgrass physiological research. Current methods, such as monitoring organic matter loss or gas exchange analysis, are effective but require a significant amount of time and a large instrument apparatus. Our objective was to develop a method for monitoring mitochondrial respiration inhibition in Agrostis stolonifera (creeping bentgrass) which is rapid in detection and requires a portable instrument. A Bruker Optics Mobile-IR Fourier transform infrared spectrometer was used to collect a mid-infrared (MIR) spectrum from a whole leaf with zero sample preparation and minimal machine preparation involved. We used MIR amide I protein peak data to compare chemically inhibited plants with an untreated control. Multivariate statistical techniques (cluster analysis and principal component analysis) were used to transform data that can be graphically represented. Cluster analysis revealed unique grouping separate from the control for azoxystrobin and trinexapac-ethyl treated plants. Additionally, Euclidean distances from the control were plotted against five chemical rates to reveal dose response curves at varying days after treatment (DAT). Plants treated with azoxystrobin showed highest respiration inhibition three DAT. Maximum inhibition of respiration for azoxystrobin was then determined to be at 1.497 and 1.657 oz./1000 sq. ft. Heritage TL application 3 DAT and 7 DAT, respectively. The FTIR technique described shows promise as a less labor intensive and more economical method for determining respiratory rates, allowing for more in depth research in turfgrass physiology and metabolism.