• Response of Grape Cultivars to Nitrogen and Phosphorus

      Stroehlein, J. L.; Janat, M. M.; McGuide, C. E.; Kilby, Michael W.; Bantlin, Marguerite (College of Agriculture, University of Arizona (Tucson, AZ), 1990-12)
      The response of 11 different varieties of grapes treated with different levels of N was studied over a seven-year period Phosphorau fertilizer was applied midway through the study. Tissue samples were tested for total P and NO₃-N content, and yield determined annually. The results showed a positive interaction in tens of increased yield between N and P when sufficient quantities of both nutrients were provided