Determination of the effects of farmyard manure and different zinc applications on soil characteristics and apricot fruit quality

This study was conducted to investigate the effects of farm manure and different zinc applications on the biochemical properties of soil and the quality of fruit in a 20-year-old Hacıhaliloğlu apricot orchard located in the Ilıca District of Darende, Malatya Province. The experiment included a control group without farm manure application and treatment groups involving farm manure combined with zinc, zinc + manganese, and zinc + boron. The results demonstrated significant improvements in both soil and fruit quality due to these applications. The zinc + boron application resulted in the highest fruit weight (36.65 g), while the control group had the lowest (30.91 g), indicating an 18.6% increase. Regarding water-soluble dry matter (WSDM) content, the zinc + manganese application achieved the highest value of 28.3%, compared to 22.7% in the control group, representing a 24.7% increase. Farm manure applications enhanced soil organic matter content by 15.2%. Furthermore, the combinations of zinc + boron and zinc + manganese increased the concentrations of boron and manganese in soil and fruit by 12.8% and 10.5%, respectively. In terms of soil biochemical properties, farm manure applications improved microbial biomass carbon (MBC) and soluble carbon (SC) levels by 18.3% and 14.7%, respectively. Similarly, microbial biomass nitrogen (MBN) and soluble nitrogen (SN) levels increased by 12.4% and 10.2%, respectively, indicating enhanced biological activity and microbial processes in the soil. These improvements contribute to better soil fertility and optimized nutrient cycling. Additionally, the farm manure and zinc combinations stabilized soil pH, supporting optimal biochemical conditions. Laboratory analyses and variance analysis results revealed statistically significant differences (P < 0.01) in physical, chemical, and biochemical parameters among the treatments. These findings indicate that farm manure and zinc applications enhance soil quality, support sustainable production, and optimize fruit quality in the Hacıhaliloğlu apricot variety. The study particularly highlights the benefits of zinc + boron and zinc + manganese applications.