Improving Phosphorus Management on Irrigated Potato

Assessed the effect of phosphorus management on potato yield and quality under Manitoba’s irrigated production systems.

IPNI-2003-CAN-MB19

27 Feb 2004

2003 Annual Interpretive Summary


Improving Phosphorus Management in Irrigated Potato Production Systems, 2003

Rapid expansion of the processing potato industry in Manitoba has generated a need for information regarding fertilizer management strategies for irrigated potato. The first year of a 3-year study was conducted in 2003 to determine the impact of phosphorus (P) fertilizer rate on potato tuber yield and quality, and the effectiveness of petiole P concentration in assessing P status of potato (cv. Russet Burbank).

A field experiment was conducted at one location near Carberry in 2003 to assess the effect of four P rates (0, 30, 60, and 90 lb P2O5/A as broadcast/incorporated monoammonium phosphate) on tuber yield and quality, petiole P status, and post-harvest soil P status. Preliminary analysis indicated that P fertilizer rate had no effect on total tuber yield, which averaged 380 cwt/A, or on tuber size distribution. Specific gravity of tubers was lower for the highest P rate compared to the other treatments. Preliminary soil test results indicated that NaHCO3-extractable P levels for the plot area averaged 13 parts per million (ppm), 0 to 6 in., which would have resulted in a recommendation for application of 40 to 45 lb P2O5/A based on provincial guidelines. Analysis of petiole and soil samples is ongoing. Studies will continue in 2004. MB-19F