Assessment of nutrient concentrations and validation of reference sufficiency ranges for current corn (Zea mays L.) hybrids under rainfed and irrigated conditions

Authors: ADOTEY, REGINA - University Of Tennessee; YIN, XINHUA - University Of Tennessee; ADOTEY, NUTIFAFA - University Of Tennessee; MCCLURE, ANGELA - University Of Tennessee; MCNEAL, JAKE - University Of Tennessee; RAPER, TYSON - University Of Tennessee; SYKES, VIRGINIA - University Of Tennessee; SHEKOOFA, AVAT - University Of Tennessee; POUREBRAHIMI, MOHIL - University Of Tennessee; He, Zhongqi

Submitted to: Field Crops Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/13/2025
Publication Date: 9/4/2025
Citation: Adotey, R.E., Yin, X., Adotey, N., Mcclure, A., Mcneal, J., Raper, T., Sykes, V., Shekoofa, A., Pourebrahimi, M., He, Z. 2025. Assessment of nutrient concentrations and validation of reference sufficiency ranges for current corn (Zea mays L.) hybrids under rainfed and irrigated conditions. Field Crops Research. 333. Acticle 110122. https://doi.org/10.1016/j.fcr.2025.110122.
DOI: https://doi.org/10.1016/j.fcr.2025.110122

Interpretive Summary: Reference Sufficiency Ranges (RSR) are the ranges of nutrient concentrations in plant tissue or soil that are considered optimal for plant growth and yield, often used in plant analysis to determine if a plant is receiving adequate nutrients. The current RSR for the southern region of the United States were established based on data collected during 1970s to early 1980s, and have been used since then without modification. Due to present substantial changes in corn traits and management practices, validation of the RSR is warranted for current corn cultivars. In other words, the current sufficiency system requires adjustments so as to match up with the yield potential of current germplasm and crop management. This study therefore aimed to (1) assess N, P, and K nutrient concentrations of current high yielding corn cultivars under rainfed and irrigated conditions and (2) validate the current RSR of N, P, and K using current corn cultivars representing early, medium, and full season relative maturity hybrids with and without irrigation. Based on the results from the 2-year field research, overall, RSR at the seedling stage is too low for current corn cultivars and too high at maturity, demanding a need for update.

Technical Abstract: Plant analysis is used as a viable tool to determine whether crop nutrients are deficient, sufficient, or excessive by comparing with conventional Reference Sufficiency Ranges (RSR). The current RSR for the southern region of the United States were established based on data collected during 1970-1980s. Due to present substantial changes in corn traits and management practices, validation of the RSR is warranted for current corn cultivars. This study aims to assess N, P, K nutrient concentrations and validate the RSR using current corn cultivars. Field set up involving a split-split-plot experimental design was implemented in 2021 and 2022. Watering regime was the whole plot factor at two levels: rainfed and irrigated. Each whole plot was divided into six subplots for six corn cultivars. Fertilizer was applied as a split-split-plot factor where each corn cultivar was evaluated under four fertilizer treatments. Compared with rainfed condition, N concentration under irrigation improved through the early growth to tasseling stages, culminating in significant (p = 0.05) yield increases with N-fertilizer treatment. Generally, seedling and early growth P concentrations were significantly (p = 0.05) higher only with P-fertilizer treatment in rainfed conditions. With the established RSR values of corn juxtaposed to nutrient concentrations from this study, the RSR occasionally correctly diagnosed deficiency in the absence of fertilizer while it sometimes diagnosed concentrations as insufficient despite adequate fertilizer application. Overall, RSR at the seedling stage is too low for current corn cultivars and too high at maturity, demanding a need for update.