AUTHOR=Abedi Mahyar , Tan Xu , Stallknecht Eric J. , Runkle Erik S. , Klausner James F. , Murillo Michael S. , Bénard André 

TITLE=Incorporating the effect of the photon spectrum on biomass accumulation of lettuce using a dynamic growth model

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1106576

DOI=10.3389/fpls.2023.1106576

ISSN=1664-462X

ABSTRACT=Cultivation studies in specialty crop optimization utilize models to estimate the fresh and dry mass yield. However, the spectral distribution and photon flux density (µmol m-2 s-1) affect plant photosynthetic rate and morphology, which is usually not incorporated in plant growth models. In this study, using data for indoor-grown lettuce (Lactuca sativa) cultivated under different light spectra, a mathematical model that incorporates these effects is presented. Different experimental cases are used to obtain a modified quantum use efficiency coefficient that varies with spectral distribution. Several models for this coefficient are fitted using experimental data and obtained values. Comparing the accuracy of these models, a simple first- or second-order linear model has about 6 to 8 percent uncertainty, while a fourth-order model has a 2 percent average error in prediction. In addition, normalizing overall spectral distribution leads to a more accurate prediction of the investigated parameter. A mathematical model based on normalized spectral irradiance integrated over wavelength for photosynthetically active radiation (PAR) wavebands and the far-red waveband is presented in this study that accurately predicts lettuce dry mass grown indoors under different light spectra.