IRUS Total

In vivo label-free mapping of the effect of a photosystem II inhibiting herbicide in plants using chlorophyll fluorescence lifetime

File Description SizeFormat 
Noble_In vivo labe-free_Plant Methods.pdfPublished version3.98 MBAdobe PDFView/Open
Title: In vivo label-free mapping of the effect of a photosystem II inhibiting herbicide in plants using chlorophyll fluorescence lifetime
Authors: Noble, E
Kumar, S
Gorlitz, F
Stain, C
Dunsby, CW
French, PMW
Item Type: Journal Article
Abstract: Background In order to better understand and improve the mode of action of agrochemicals, it is useful to be able to visualize their uptake and distribution in vivo, non-invasively and, ideally, in the field. Here we explore the potential of plant autofluorescence (specifically chlorophyll fluorescence) to provide a readout of herbicide action across the scales utilising multiphoton-excited fluorescence lifetime imaging, wide-field single-photon excited fluorescence lifetime imaging and single point fluorescence lifetime measurements via a fibre-optic probe. Results Our studies indicate that changes in chlorophyll fluorescence lifetime can be utilised as an indirect readout of a photosystem II inhibiting herbicide activity in living plant leaves at three different scales: cellular (~μm), single point (~1 mm2) and macroscopic (~8 × 6 mm2 of a leaf). Multiphoton excited fluorescence lifetime imaging of Triticum aestivum leaves indicated that there is an increase in the spatially averaged chlorophyll fluorescence lifetime of leaves treated with Flagon EC—a photosystem II inhibiting herbicide. The untreated leaf exhibited an average lifetime of 560 ± 30 ps while the leaf imaged 2 h post treatment exhibited an increased lifetime of 2000 ± 440 ps in different fields of view. The results from in vivo wide-field single-photon excited fluorescence lifetime imaging excited at 440 nm indicated an increase in chlorophyll fluorescence lifetime from 521 ps in an untreated leaf to 1000 ps, just 3 min after treating the same leaf with Flagon EC, and to 2150 ps after 27 min. In vivo single point fluorescence lifetime measurements demonstrated a similar increase in chlorophyll fluorescence lifetime. Untreated leaf presented a fluorescence lifetime of 435 ps in the 440 nm excited chlorophyll channel, CH4 (620–710 nm). In the first 5 min after treatment, mean fluorescence lifetime is observed to have increased to 1 ns and then to 1.3 ns after 60 min. For all these in vivo plant autofluorescence lifetime measurements, the plants were not dark-adapted. Conclusions We demonstrate that the local impact of a photosystem II herbicide on living plant leaves can be conveniently mapped in space and time via changes in autofluorescence lifetime, which we attribute to changes in chlorophyll fluorescence. Using portable fibre-optic probe instrumentation originally designed for label-free biomedical applications, this capability could be deployed outside the laboratory for monitoring the distribution of herbicides in growing plants.
Issue Date: 15-Jun-2017
Date of Acceptance: 9-Jun-2017
URI: http://hdl.handle.net/10044/1/49071
DOI: https://dx.doi.org/10.1186/s13007-017-0201-7
ISSN: 1746-4811
Publisher: BioMed Central
Journal / Book Title: Plant Methods
Volume: 13
Copyright Statement: © The Author(s) 2017. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/ publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
Sponsor/Funder: Biotechnology and Biological Sciences Research Council (BBSRC)
Engineering & Physical Science Research Council (EPSRC)
Biotechnology and Biological Sciences Research Council (BBSRC)
Funder's Grant Number: BB/E000495/1
Keywords: Science & Technology
Life Sciences & Biomedicine
Biochemical Research Methods
Plant Sciences
Biochemistry & Molecular Biology
Fluorescence spectroscopy
Photosystem II
Chlorophyll fluorescence lifetime
Plant Biology & Botany
0607 Plant Biology
1001 Agricultural Biotechnology
Publication Status: Published
Article Number: 48
Appears in Collections:Physics
Biological and Biophysical Chemistry
Faculty of Natural Sciences