Effect of spraying urea and addition of potassium on growth parameters of local citrus seedling (Citrus sinensis L.) grafted on sour orange rootstock

The effects of different levels of urea spray (0, 0.5, 1, 2%) with a total number of five spraying. The interval between each spray was one month. The second-factor addition of potassium fertilizer (potassium sulfate) applied of partitioning for five batches, the concentration of potassium sulfate was 50 g per seedling. The results revealed that a significant association of the concentration of the urea and growth indicators of the seedlings, by giving the highest averages for seedling length, stem diameter, total leaves number, leaf area, dry weight, the leaves content of chlorophyll, nitrogen, phosphorus, and potassium. Similarly, the potassium fertilizer application was significantly correlated to the growth indicators for a citrus seedling. However, the urea alone or combined with the addition of potassium at the early stages of growth could be useful in improving seedling quality.