Investigating Nitrogen Absorption Through Two Fertilizer Application Methods in Tillandsia ionantha

Abstract

By Joshua Anzalone, anthropology; Alexis Morad, anthropology

Advisor: Brooke Crowley

Presentation ID: PM_ATRIUM10

Abstract: The purpose of this study is two-fold: First, to determine if nitrogen isotope (_15N) values and weight percent nitrogen (%N), can determine nitrogen uptake in plant foliage; and second, to determine which of the two methods of fertilization, dunking or spraying, is most effective at fertilizing an epiphyte, Tillandsia ionantha. We expected that _15N and %N will accurately reflect the applied nitrogen and that of the two methods, dunking will cause more rapid nitrogen uptake. Five plants were sprayed and five plants were dunked in an Espoma Garden Tone fertilizer, a delayed release organic fertilizer with isotopically distinct nitrogen. While two control plants were sprayed with water. All plants were then watered with a mister on a weekly basis for the duration of the project. Three rounds of samples were collected: Immediately; three days, and two months after applying fertilizer. Results suggest that both _15N and %N reflected nitrogen uptake in the epiphytes' foliage. Dunking resulted in more nitrogen absorption. However, the samples that were dunked displayed evidence of over-fertilization. The samples that were sprayed took up less N but had better overall health from gradual nitrogen absorption. Nitrogen isotopes and %N have potential uses in greenhouses and other horticultural and agricultural contexts for tracking and controlling fertilizer use.