Narangerel Altangerel, Gombojav O. Ariunbold, Connor Gorman, Masfer H. Alkahtani, Eli J. Borrego, Dwight Bohlmeyer, Philip Hemmer, Michael V. Kolomiets, Joshua S. Yuan, and Marlan O. Scully

Significance

Feeding a population of 9 billion in 2050 coupled with the changing climate and environmental stresses motivate us to develop advances in plant science and technology. We present a high-throughput plant phenotyping platform for detection of abiotic stress. The proposed Raman spectroscopic technique for high-throughput stress phenotyping and early stress detection in vivo improves sensitivity with the ability to interrogate individual molecules simultaneously in plants. This technology holds promise for mobile automated systems and precision agriculture.

Abstract

Development of a phenotyping platform capable of noninvasive biochemical sensing could offer researchers, breeders, and producers a tool for precise response detection. In particular, the ability to measure plant stress in vivo responses is becoming increasingly important. In this work, a Raman spectroscopic technique is developed for high-throughput stress phenotyping of plants. We show the early (within 48 h) in vivo detection of plant stress responses. Coleus (Plectranthus scutellarioides) plants were subjected to four common abiotic stress conditions individually: high soil salinity, drought, chilling exposure, and light saturation. Plants were examined poststress induction in vivo, and changes in the concentration levels of the reactive oxygen-scavenging pigments were observed by Raman microscopic and remote spectroscopic systems. The molecular concentration changes were further validated by commonly accepted chemical extraction (destructive) methods. Raman spectroscopy also allows simultaneous interrogation of various pigments in plants. For example, we found a unique negative correlation in concentration levels of anthocyanins and carotenoids, which clearly indicates that plant stress response is fine-tuned to protect against stress-induced damages. This precision spectroscopic technique holds promise for the future development of high-throughput screening for plant phenotyping and the quantification of biologically or commercially relevant molecules, such as antioxidants and pigments.

See http://www.pnas.org/content/114/13/3393.abstract.html?etoc

PNAS March 28 2017; vol.114; no.13:  3393–3396

Fig. 1.

A simultaneous and in vivo detection of anthocyanins and carotenoids, which are reactive oxygen-scavenging pigments, by the Raman technique.