https://doi.org/10.37229/fsa.fjh.2026.09.04

Alternate bearing is a major phenomenon limiting the sustainable production of 'Balady' mandarin (Citrus reticulata Blanco), leading to inconsistent yields and fluctuating fruit quality. This three-season study (2021–2023) in Nubaria region, Egypt, evaluated various pruning intensities (25, 50, and 75%) and thinning applications (manual and chemical) at different stages on 20-year-old trees to stabilize yields. Combined analysis across three seasons revealed that all pruning levels increased tree volume by 78.46%, 62.98%, and 32.13% respectively, above the control. Early and late chemical thinning enhanced leaf nutrient accumulation, including nitrogen and boron under early application, and iron and zinc under late application. The control recorded higher fruitlet and fruit retention percentages, which logically responds to removing fruiting shoots during pruning and the direct removal of fruitlets during thinning. However, early chemical thinning and moderate pruning (50%) achieved a superior balance between vegetative growth and reproductive potential by improving shoot C: N ratios (12.58 and 12.39, respectively) over the control; thus, establishing enhanced yield (kg/tree and ton/feddan) and yield efficiency (kg/m³) while minimizing the biennial bearing index. Furthermore, fruit weight, Vitamin C, and TSS: acid ratio was markedly improved under these treatments. Overall, adopting either early chemical thinning or moderate pruning is recommended as an effective horticultural practice to ensure consistent, high-quality production and maintain tree longevity under experimental conditions.