Effect of different ammonium and nitrate ratios on quantitative and qualitative characteristics of apple varieties (Golabe-Kohanz and Granny Smith)

In this study, the effect of 5 nutrient solutions containing different ratios of ammonium nitrogen to total nitrogen on quantity and quality properties of two apple varieties (Golabe-Kohanz and Granny Smith), were studied. One of the nutrient solution (number 1) had no ammonium nitrogen but the ammonium to total nitrogen ratios of other nutrient solutions were, 0.04, 0.07, 0.10, 0.14 meq/liters, respectively. Fresh weight, length, diameter and length to diameter ratio of fruits (shape of fruits), fruit firmness, pH, total soluble solids (TSS), titrable acidity (TA) and TSS / TA ratios were evaluated. When ammonium nitrogen increased in nutrient solutions there was no significant difference in fruits fresh weight and shape of fruits. While firmness, pH, total soluble solids significantly decreased when the ammonium to total nitrogen ratios increased in nutrient solutions.