AUTHOR=Estrada Félix , Flexas Jaume , Araus Jose Luis , Mora-Poblete Freddy , Gonzalez-Talice Jaime , Castillo Dalma , Matus Ivan A. , Méndez-Espinoza Ana Maria , Garriga Miguel , Araya-Riquelme Carlos , Douthe Cyril , Castillo Benjamin , del Pozo Alejandro , Lobos Gustavo A. 

TITLE=Exploring plant responses to abiotic stress by contrasting spectral signature changes

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.1026323

DOI=10.3389/fpls.2022.1026323

ISSN=1664-462X

ABSTRACT=<p>In this study, daily changes over a short period and diurnal progression of spectral reflectance at the leaf level were used to identify spring wheat genotypes (<italic>Triticum aestivum</italic> L.) susceptible to adverse conditions. Four genotypes were grown in pots experiments under semi-controlled conditions in Chile and Spain. Three treatments were applied: i) control (<italic>C</italic>), ii) water stress (<italic>WS</italic>), and iii) combined water and heat shock (<italic>WS+T</italic>). Spectral reflectance, gas exchange and chlorophyll fluorescence measurements were performed on flag leaves for three consecutive days at anthesis. High canopy temperature (<bold><italic>H</italic></bold><italic><sub>CT</sub></italic>) genotypes showed less variability in their mean spectral reflectance signature and chlorophyll fluorescence, which was related to weaker responses to environmental fluctuations. While low canopy temperature (<bold><italic>L</italic></bold><italic><sub>CT</sub></italic>) genotypes showed greater variability. The genotypes spectral signature changes, in accordance with environmental fluctuation, were associated with variations in their stomatal conductance under both stress conditions (<italic>WS</italic> and <italic>WS+T</italic>); <bold><italic>L</italic></bold><italic><sub>CT</sub></italic> genotypes showed an anisohydric response compared that of <bold><italic>H</italic></bold><italic><sub>CT</sub></italic>, which was isohydric. This approach could be used in breeding programs for screening a large number of genotypes through proximal or remote sensing tools and be a novel but simple way to identify groups of genotypes with contrasting performances.</p>