Degree Type
Dissertation
Date of Award
2019
Degree Name
Doctor of Philosophy
Department
Horticulture
Major
Horticulture
First Advisor
Christopher J. Currey
Abstract
Lighting influences plant growth and development on a quantity and quality basis, promoting the production of both primary and secondary metabolites. While the amount of light necessary for culinary herb production is species-specific, with growth curves for increasing daily light integrals (DLI), the specific spectra of incidental light absorbed plays a role in photosynthetic efficiency, biomass partitioning, and secondary metabolites related health and nutrition. The two primary objectives of this research were to 1) Quantify morphological growth of culinary herbs under increasingly higher DLI, and 2) Identify the morphological, physiological, and phytochemical responses of selected herbs to the spectral composition of light sources and blue light fraction from either supplemental or sole-source lighting. Biomass increased with increasing DLI, and the relationship was either linear or quadratic, depending upon saturating DLI. Additionally, the proportions of light spectra affected plant height, biomass, gas exchange, photosynthetic efficiency, and phenolic accumulation by alteration of blue light fraction, or use of broad-spectrum lighting. By identifying responses of plants to light quantity and quality, the goal of this research was to 1) Provide information on light quantity optimization in food crop production, and 2) Improve the quality of food crops produced by emphasizing the promotion of plant photoprotective compounds that increase both production efficiency and food nutrition.
Copyright Owner
Alexander Gaston Litvin-Zabal
Copyright Date
2019-05
Language
en
File Format
application/pdf
File Size
131 pages
Recommended Citation
Litvin-Zabal, Alexander Gaston, "Quantifying the effects of light quantity and quality on culinary herb physiology" (2019). Graduate Theses and Dissertations. 17042.
https://lib.dr.iastate.edu/etd/17042