2018 journal article
Effects of Carbon Dioxide and Photosynthetic Photon Flux on Mineral Content in Chrysanthemum Allowing for Growth as a Covariate
HORTSCIENCE, 53(1), 73–77.
The effect of CO 2 concentration (330 and 675 μL·L −1 ) and photosynthetic photon flux ( PPF ) (mean daily peaks of 550–1400 μmol·m −2 ·s −1 ) on total mineral contents in shoots was studied in chrysanthemum [ Dendranthema × grandiflorum (Ramat) Kitam ‘Fiesta’] during three times of the year. Growth (as measured by shoot dry weight) and shoot mineral contents (weight of nutrient per shoot) of hydroponically grown plants were analyzed after 5 weeks. There was a positive synergistic interaction of CO 2 concentration and PPF on growth with the greatest growth at high PPF (1400 μmol·m −2 ·s −1 ) with high CO 2 (675 μL·L −1 ). When growth was not used as a covariate in the statistical model, both CO 2 concentration and PPF significantly affected the content of all eight nutrients. However, after growth was included as a covariate in the model, nutrients were classified into three categories based on whether CO 2 concentration and PPF level were needed in addition to growth to predict shoot nutrient content. Neither CO 2 concentration nor PPF level was needed for Mg, Fe, and Mn contents, whereas PPF level was needed for N, P, K, and Ca contents, and both CO 2 concentration and PPF level were required for B content.