NITRATE UPTAKE EFFECTIVENESS AND UTILIZATION EFFICIENCY OF 2 PLUM CLONES

Nitrate uptake and utilization efficiencies of two plum clones, Marianna 2624 (Prunus cerasifera×Prunus munsoniana?) and Myrobalan 3‐J (Prunus cerasifera) in stirred solution cultures were investigated. Myrobalan 3‐J had a significantly lower NO3‐ compensation point (i.e., greater capacity for nitrate depletion) but ceased growth earlier than Marianna 2624 under severe N stress. The maximum velocity of NO3‐ uptake was 33% higher in Marianna 2624 than Myrobalan 3‐J. The nitrogen efficiency ratio (i.e., mg dry weight produced/mg nitrogen absorbed) of Marianna 2624 was 40% higher than Myrobalan 3‐J when nitrogen was severely limiting (28 mg nitrogen per plant). Thus, Marianna 2624 plants may be capable of growth at lower mean nitrogen concentrations. Copyright © 1979, Wiley Blackwell. All rights reserved