In the current study, a field experiment of two years (2023 and 2024) was conducted on acid lime (Citrus aurantifolia Swingle) to evaluate the effect of poultry litter (PL) amended with biochar (B) or zeolite (Z) in combination with mineral nitrogen fertilizer (MNF) on nutrient availability, growth, yield, and fruit quality of acid lime. This experiment was divided into five treatments, which included: (1) 50% of the recommended nitrogen (N) rate through MNF (50%MNF), (2) 100% of the recommended N rate through MNF (100%MNF), (3) 50% of the recommended N rate through MNF + poultry litter (PL + 50%MNF), (4) 50% of the recommended N rate through MNF+ biochar-amended poultry litter (BPL + 50%MNF), and (5) 50% of the recommended N rate through MNF + zeolite-amended poultry litter (ZPL + 50%MNF). In the first season, applying ZPL + 50%MNF significantly increased soil available nitrogen compared to the 100%MNF treatment. Soil available potassium significantly increased in the first season when BPL + 50%MNF and ZPL + 50%MNF were applied, compared with the rest of the treatments. Significant increase in soil available phosphorus in the first season with applying BPL + 50%MNF compared to the 50%MNF, 100%MNF, and PL treatments. The highest acid lime yields were obtained from the BPL + 50% MNF and ZPL + 50% MNF treatments, recording 15.41 and 15.84 ton/ha, and 16.10 and 16.26 ton/ha in the first and second seasons, respectively. The highest values of total soluble solids, total acidity, and vitamin C content were observed when adding the BPL + 50%MNF and ZPL + 50%MNF treatments during two seasons. Based on these findings, the study suggests that the application of 10 kg of poultry litter amended with biochar or zeolite and 0.5 kg N as ammonium nitrate per acid lime tree enhances nutrient availability and fruit yield of acid lime while reducing reliance on nitrogen chemical fertilizers. It recommends considering poultry litter amended with biochar or zeolite for soil reclamation and as an alternative to traditional fertilizers.
Gaber et al. (Mon,) studied this question.