Effect of Fertilization with Seaweed Extract and High K-P Mixture on Leaf Nutritional Content in Citrus Rootstock C-35

The experiment was conducted in the citrus production nursery/Al-Hindiya District/province of Karbala, Iraqi for the period 10/4 -to 10/12/2021. The study aimed to evaluate citrus rootstock C-35 saplings response to four fertilization levels of SWE (0.0, 0.5, 1.0, 1.5 g. L-1) and/or high K-P mixture (0.0, 0.5, 1.5, 2.5 g.plant-1) and their interaction effects. Both fertilizers were monthly applied (six times) except for July and August. The treatments were distributed as Randomized Complete Block Design (RCBD) factorial experiment with three replications. The results showed that leaf content of nutrients (nitrogen, phosphorous, potassium, iron, zinc, and boron) was significantly higher when SWE was used at 1.5 and 1.0 g.L-1 and High potassium-phosphorus fertilizer at 2.5 g.plant-1. The interaction of 1.5 g.L-1 SWE and 2.5 g.plant-1 K-P fertilizer caused a significant increase in most parameters tested in C-35 citrus rootstock seedlings leaves.