Improving zinc and copper delivery for subirrigated greenhouse-grown pot chrysanthemums

Moderate levels of zinc (3.50, 1.75 or 0.875 μmol LThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Improving Boron and Molybdenum Use Efficiencies in Contrasting Cultivars of Subirrigated Greenhouse-Grown Pot Chrysanthemums

Fertilizer boron (B) and molybdenum (Mo) were provided to contrasting cultivars of subirrigated pot chrysanthemums at approximately 6–100% of current industry standards in an otherwise balanced nutrient solution during vegetative growth, and then all nutrients were removed during reproductive growth. Two experiments were conducted for each nutrient in a naturally lit greenhouse using a randomized complete block split-plot design. Boron (0.313–5.00 µmol L−1) or Mo (0.031–0.500 µmol L−1) was the main plot, and cultivar was the sub-plot. Petal quilling was observed with leaf-B of 11.3–19.4 mg kg−1 dry mass (DM), whereas Mo deficiency was not observed with leaf-Mo of 1.0–3.7 mg kg−1 DM. Optimized supplies resulted in leaf tissue levels of 48.8–72.5 mg B kg−1 DM and 1.9–4.8 mg Mo kg−1 DM. Boron uptake efficiency was more important than B utilization efficiency in sustaining plant/inflorescence growth with decreasing B supply, whereas Mo uptake and utilization efficiencies appeared to have similar importance in sustaining plant/inflorescence growth with decreasing Mo supply. This research contributes to the development of a sustainable low-input nutrient delivery strategy for floricultural operations, wherein nutrient supply is interrupted during reproductive growth and optimized during vegetative growth