Use of Infrared Spectroscopy for In-Field Measurement and Phenotyping of Plant Properties: Instrumentation, Data Analysis, and Examples

Abstract: Recent developments in agricultural technology have led to a demand for a new era of nondestructive methods of plant analysis in the field rather than in the laboratory. The combination of fundamental science (e.g., plant physiology, biochemistry, and other disciplines), multivariate data analysis, and spectroscopy will enable the development of technologies for reliable and rapid on-farm or in-field low-cost testing. This will enable both farmers and scientist to maximize sales in existing markets and to target new markets with differentiated products or select new varieties, better soil management, among other issues. Infrared (IR) spectroscopy has been successfully applied for the determination of composition analysis in several fields (e.g., agriculture, pharmaceutical, etc.) and in product quality assessment and production control. The IR spectrum can give a global signature of composition (fingerprint), which, with the application of chemometric techniques, can be used to elucidate particular compositional characteristics not easily detected by traditional targeted chemical analyses. This article highlights the principles of IR spectroscopy, commercially available instruments and software, and calibration issues including calibration development, networking, and transfer. In addition, recent and potential applications of IR spectroscopy in grains, fruits, and other plant tissues are presented and discussed.