Characterization of fluorescence properties of wounds on soybean seedlings during healing process using excitation emission matrix and fluorescence imaging

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2023-10, Vol.298, p.122766, Article 122766
• Main Authors: Saito, Yoshito, Ito, Yuma, Tada, Terufumi, Shoda, Aina, Shiraiwa, Tatsuhiko, Kondo, Naoshi
• Format: Article
• Language: English
• Subjects: Excitation emission matrix (EEM); Fluorescence characteristics; Fluorescence imaging; Glycine max (L.) Merr; Soybean; Wound healing
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2023.122766

[Display omitted] •Fluorescence characteristics of wounds on soybean hypocotyls were measured.•Excitation emission matrices on wounds showed three main fluorescence peaks.•Fluorescence color taken by wavelength of 365 nm changed from red to blue-green.•Formation of new tissues on wounds might change the fluorescence characteristics.•Fluorescence can be a new indicator for evaluating wound healing ability of plants. To establish a simple and nondestructive method for measuring plant wound-healing ability, we characterized the fluorescence characteristics of wounds on hypocotyl of soybean seedlings during healing process. Wounds were manually created on the stem of soybean seedlings 7 days after sowing. The fluorescence time-series characteristics of the wounds were measured until 96 h after wounding using excitation emission matrix (EEM) and fluorescence images excited by wavelength of 365 nm. In the EEM of wounds, three main fluorescence peaks were observed, and the intensity decreased with time after wounding. The reddish color due to chlorophyll in fluorescence images also decreased with healing process. In addition, microscopic observation of the wounded tissue using a confocal laser microscope showed that the intensity of lignin or suberin like fluorescence increased with healing time, which might have blocked the excitation light. These results suggest that UV-excited fluorescence can be a new indicator of the healing ability of plant tissues.