LAUSR

Global phosphate mineral resources are nonrenewable and are inevitably depleting. Exploiting elite varieties has become imperative for the efficient use of phosphorus (P) for sustainable crop production. Three potato varieties were hydroponically evaluated for P mobilization, uptake, and utilization efficiencies at different P levels and sources during 28 d seedling growth. ‘Harley Blackwell’, ‘La Chipper’, and ‘Red LaSoda’ were selected from a previous study and grown in modified Hoagland solution, with different P concentrations of soluble high P as NaH2PO4 (10 mg L−1 P), soluble low P (1 mg L−1 P), and 286 mg L−1 sparingly soluble P as tri-calcium phosphate [TCP, Ca3(PO4)2] with 2286 mg L−1 CaSO4. ‘Harley Blackwell’ and ‘La Chipper’ had significantly greater biomass than ‘Red LaSoda’ in the low P or TCP treatments. In low-P stress, P utilization efficiency was significantly greater for ‘Harley Blackwell’ than that of the other two varieties. ‘Red LaSoda’ was more efficient in P mobilization from TCP as compared to the other two cultivars. The holistic score analysis indicated that ‘Harley Blackwell’ was the most P-efficient while ‘Red LaSoda’ was the least P-efficient. The results of this study show that the TCP solution was successful for screening P-efficient potato varieties.