Date of Award:

5-2015

Document Type:

Thesis

Degree Name:

Master of Science (MS)

Department:

Plants, Soils, and Climate

Department name when degree awarded

Plant, Soils, and Climate

Committee Chair(s)

Grant E. Cardon

Committee

Grant E. Cardon

Committee

Brent L. Black

Committee

Paul R. Grossl

Abstract

Fruit tree nutrition requirements change during the growing season as buds form, shoots grow, fruit sets, and internal reserves are filled. Nutrient concentrations in plant tissues are directly correlated with the nutritional status and productivity of fruit trees. Plant tissue testing is used to effectively and accurately determine the nutritional status of perennial plants. Tissue test analyses were performed on tart cherry (Prunus cerasus) and peach (Prunus persica) leaves to validate tissue sufficiency levels used in Utah and to determine optimal timing of tissue sampling for prediction of harvest nutrient status, focusing on phosphorus (P), potassium (K), calcium (Ca), iron (Fe), and zinc (Zn). Sufficiency limits that are currently used in Utah were developed in the 1960s from research data accumulated from the primary fruit growing regions in the United States. Limited research has been conducted under Utah growing conditions to validate nutrient sufficiency levels. Nutrient concentrations from tart cherry and peach leaves were compared against currently used sufficiency limits. Tissue nutrient concentrations over time correlated well with current sufficiency limits and observed nutrient deficiencies in the field. Tissue concentrations of P, K, Fe, and Zn were found to be chronically low in Utah orchards. Growers can have confidence that sufficiency limits being used to apply fertilizer management practices are valid. Three sampling dates were selected to look at nutrient content over time at bloom, mid-season, and pre-harvest. Plant tissue data establishes that sampling in the middle of the growing season can predict nutrient status at harvest. Mid-season sampling also allows time for growers to correct deficient or excess nutrients found in the plants to maintain sufficiency levels and reach maximum fruit production. Nutrient management practices are generally applied annually to increase yield, fruit quality, and overall health of an orchard. Yield was measured on previously treated tart cherry orchards to determine fertilizer carryover in perennial plants. Orchards were treated 2 to 3 years prior with formulations of P and K to maximize yield and fruit quality; one has been using recommended fertilizer rates for Utah since then and the other continued with their less aggressive management applications. The less aggressively managed orchard showed trends across treatments, but differences were not significant. Annual fertilizer applications may not immediately show effect during year of application, but long term management is essential for overall productivity of orchards.

Checksum

4778e79f8e967777cd164d27c378d40f

Download

Share

COinS

Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .