Leaf Nutrients and Yields of Irrigated Peanut in the Southern High Plains: Influence of Nitrogen, Phosphorus, and Zinc Fertilizer

Abstract

Fertilizer response studies for peanut (Arachis hypogaea L.) in the semi-arid, alkaline soil regions of the western United States have been few. Peanut in the Southern High Plains is a relatively new crop and soil test–fertilizer response information is needed. A three-year factorial study was conducted of irrigated peanut with one rate of nitrogen (N), phosphorus (P), and zinc (Zn) fertilizer. Nitrogen fertilizer response was observed in only one of three years, and may have been related to herbicide injury. No response to P or Zn fertilizer was observed, despite below critical soil test P in all three years, and below critical soil Zn in one year. Leaf N, P, and potassium (K) at mid bloom or mid pegging responded inconsistently to fertilizer additions. However, leaf P was correlated with peanut yields in two of three years. In-season multispectral reflectance responded occasionally to fertilizer applications. Chlorophyll meter readings were positively affected by N in 2000 and 2001, and by P in 2001. In these same instances, chlorophyll meter readings were correlated with leaf N and P. This study demonstrates that fertilizer response in peanut is hard to document in the Southern Plains, and that more research is needed with this crop.