EFFECT OF DIFFERENT RATIOS OF N, P AND K ON YIELD AND QUALITY OF FLAME SEEDLESS GRAPE GRAFTED ON SALT CREEK ROOTSTOCK EFFECT OF DIFFERENT RATIOS OF N, P AND K ON YIELD AND QUALITY

Abstract

The effect of different ratios of NPK on performance of Flame seedless grapes grafted on salt creek rootstock was studied during 2014 and 2015 seasons. The vines were four years old, grown in a sandy soil under drip irrigation system. Three levels of nitrogen 20, 40 and 60 kg/ feddan as net nitrogen were applied, potassium levels were added at the ratio of 1:1 ; 1:2 and 1:3 from nitrogen levels whereas phosphorus level was added at the half dose of nitrogen 10, 20 and 30 kg/feddan. The plants received 40 kg N + 20 kg P and 120 kg K per feddan was the common fertilization applied in the orchard and considered as control plants. The treatment of 40 + 20 + 80 kg / feddan of NPK fertilizers significantly increased total yield (kg / vine), cluster weight, cluster length, berry length, berry diameter, weight of 100 berries, TSS % , TSS/acid ratio and total anthocyanin. It could be recommended by fertilizing Flame seedless grapes grafted on salt creek rootstock with 40 kg/feddan of nitrogen plus 20 kg/phosphorus plus 120 kg/feddan of potassium to improve berries coloration which considered the main problem in Flame seedless grafted on vigor rootstock such as salt creek.