Optimizing Phosphorus Fertilizer Management for Maximum Phosphorus Use Efficiency and Maximum Economic Returns in Potato Production
Date & Time
Monday, July 18, 2022, 3:15 PM

With the increasing cost of fertilizers, it has become more important than ever to optimize fertilizer application for increased tuber yield and maximum economic returns. The common form of phosphorus (P) fertilizer used in Colorado is liquid ammonium phosphate (10-34-0). Other forms of liquid P fertilizers are available on the market but are relatively expensive compared to 10-34-0.The agronomic use efficiency and economic returns of applying blended 10-34-0 with other liquid P fertilizers has not been documented. The objective of this study was to evaluate tuber yield and quality response of Russet potato to application of blended liquid P fertilizers, and the economic returns of blending the cheaper 10-34-0 with the more expensive liquid P fertilizers. Four relatively expensive liquid P fertilizers were used in the study (8-21-5, 3-18-18, 9-24-3, and 8-22-2), with 10-34-0 as the control P fertilizer. Treatments consisted of blending 16.8 kg ha-1 each of the expensive P fertilizers with 95.2 kg or 76.8 kg ha-1of 10-34-0. For each of the P fertilizers studied, the blend with 76.2 kg ha-1 of 10-34-0 resulted in higher agronomic P use efficiency than the blend with 95.2 kg ha-1 of 10-34-0, or when 10-34-0 was applied alone, for the 114 – 454 g and > 170 g tuber yields. Blending 10-34-0 with 16.8 kg ha-1 of the more expensive P fertilizers increased tuber yield of Canela Russet compared to applying 10-34-0 as the sole source of P fertilizer. Cost benefit analysis of the yield data showed higher net returns for 114 – 454 g, >170 g, and >284 g tuber yields when 10-34-0 was blended with any of the liquid P fertilizers, compared to applying 10-34-0 alone. It was observed that each liquid P fertilizer had its unique advantage in terms of which tuber size group improved in yield when blended with 10-34-0.

Session Type
Parent Session
7/18 - Concurrent Sessions B