Growth Response of Platycladus Orientalis (l.) Franco Seedling to Foliar Application of Ga3 And Chelated Nano N.p.k Fertilizer

Abstract

As part of the ongoing efforts to optimize the application of Nanotechnology in forestry nurseries, the current study came to determine the efficiency of Nano N.P.K-fertilizer and Gibberellic acid in enhancing the growth of the slow-growing species Platycladus orientalis (L.) Franco seedlings. One–year old of P. orientalis seedlings grown in a  greenhouse were been subjected from September 2021 to the  end of Jun 2022 to two and four foliar sprays, four different levels of Nano-fertilizer N.P.K (20:20:20) (control, 1 g. L-1, 2 g. L-1 and 3 g. L-1) and three GA3 levels (control, 300 mg. L-1 and 600 mg.L-1). The experiment was designed according to the RCBD with 1008 seedlings arranged in three replicates with 14 seedlings in each of the 72 experimental units. Duncan's multiple-range test was used for comparing all means. for each factor individually revealed that increasing Nano N.P.K up to 3 g. L-1 and GA3 up to 300 and 600 mg.L-1 increased significantly the values of most of the studied parameters (seedling high, diameter, number of branches, total seedling dry weight, leaf chlorophyll, Protein (%), and percentage of leaf nutrients content as Nitrogen, Phosphorus and Potassium. Increasing the sprays number from two to four increased the values of the studied parameters except for the Diameter, Nitrogen, Chlorophyll, and Protein parameters. The interaction effect between four sprays,  Nano N.P.K 3 g. L-1 and GA3 at rate 600 mg.L-1  significantly increased the values of all studied parameters except Potassium (%), where two sprays,  of 3 g. L-1 Nano N.P.K with 600mg.L-1  of GA3 recorded the highest values. In general, the study revealed the positive role of the foliar application of Nano N.P.K fertilizer separately and in combination with GA3 in accelerating most growth parameters of the slow-growing P. orientalis ornamental shrub