Response of Apple Saplings to the Addition of Processed Poultry Waste and Spraying with the Growth Regulator “CPPU”

Background: The study was designed to enhance the growth and biochemical composition of the saplings, therefore accelerating their attainment of optimal growth for transplantation to their permanent sites. Methods: A factorial experiment was performed using an RCBD with 12 treatments and three replications. A total of 108 apple saplings cv. Sharabi were used. The effects of poultry manure and CPPU were assessed on vegetative and root growth, leaf area, total chlorophyll and leaf P, K, Ca and Mg contents. Result: The results revealed that the addition of processed poultry waste significantly affected all characteristics with the high level (150 g pot-1) exhibited superior values for all traits. Conversely, applying the growth regulator CPPU through spraying had a significant impact on all characteristics, with treatment (9 mg L-1) achieving the best significant effect for all traits. The interaction between the two investigated factors exerted a significant effect on all evaluated parameters, with the exception of leaf phosphorus content. Notably, the (150 g pot-1 + 9 mg L-1) treatment combination yielded the optimal values across all assessed traits, whereas the minimum values were consistently recorded under the control treatment.