A high-throughput method for measuring critical thermal limits of leaves by chlorophyll imaging fluorescence
Date
2021
Authors
Arnold, Pieter
Briceño, Verónica F
Gowland, Kelli M
Catling, Alexandra A
Bravo, León A
Nicotra, Adrienne B
Journal Title
Journal ISSN
Volume Title
Publisher
CSIRO Publishing
Abstract
Plant thermal tolerance is a crucial research area as the climate warms and extreme weather events become more frequent. Leaves exposed to temperature extremes have inhibited photosynthesis and will accumulate damage to PSII if tolerance thresholds are exceeded. Temperature-dependent changes in basal chlorophyll fluorescence (T-F0) can be used to identify the critical temperature at which PSII is inhibited. We developed and tested a high-throughput method for measuring the critical temperatures for PSII at low (CTMIN) and high (CTMAX) temperatures using a Maxi-Imaging fluorimeter and a thermoelectric Peltier plate heating/cooling system. We examined how experimental conditions of wet vs dry surfaces for leaves and heating/cooling rate, affect CTMIN and CTMAX across four species. CTMAX estimates were not different whether measured on wet or dry surfaces, but leaves were apparently less cold tolerant when on wet surfaces. Heating/cooling rate had a strong effect on both CTMAX and CTMIN that was species-specific. We discuss potential mechanisms for these results and recommend settings for researchers to use when measuring T-F0. The approach that we demonstrated here allows the high-throughput measurement of a valuable ecophysiological parameter that estimates the critical temperature thresholds of leaf photosynthetic performance in response to thermal extremes.
Description
Keywords
chlorophyll, fluorescence, plant leaves, cold temperature, hot temperature
Citation
Collections
Source
Functional plant biology : FPB
Type
Journal article
Book Title
Entity type
Access Statement
Open Access