Effect of leaf temperature on the estimation of photosynthetic and other traits of wheat leaves from hyperspectral reflectance

Document Type

Article

Publication Date

11-30-2020

Journal Title

Journal of Experimental Botany

ISSN

ISSN: 0022-0957, eISSN: 1460-2431

Keywords

Chlorophyll content, electron transport rate, hyperspectral reflectance, leaf dry mass per area, leaf nitrogen, leaf temperature, Rubisco carboxylation activity, Triticum aestivum

Disciplines

Agricultural Science | Agronomy and Crop Sciences

Abstract

A growing number of leaf traits can be estimated from hyperspectral reflectance data. These include structural and compositional traits, such as leaf mass per area (LMA) and nitrogen and chlorophyll content, but also physiological traits such a Rubisco carboxylation activity, electron transport rate, and respiration rate. Since physiological traits vary with leaf temperature, how does this impact on predictions made from reflectance measurements? We investigated this with two wheat varieties, by repeatedly measuring each leaf through a sequence of temperatures imposed by varying the air temperature in a growth room. Leaf temperatures ranging from 20 °C to 35 °C did not alter the estimated Rubisco capacity normalized to 25 °C (Vcmax25), or chlorophyll or nitrogen contents per unit leaf area. Models estimating LMA and Vcmax25/N were both slightly influenced by leaf temperature: estimated LMA increased by 0.27% °C–1 and Vcmax25/N increased by 0.46% °C–1. A model estimating Rubisco activity closely followed variation associated with leaf temperature. Reflectance spectra change with leaf temperature and therefore contain a temperature signal.

Link to Full Text

Share

COinS
 

Digital Object Identifier (DOI)

https://doi.org/10.1093/jxb/eraa514