Iranian Medicinal Plants Society Journal of Medicinal plants and By-products 2322-1399 15 3 2026 05 01 Mitigating Drought Stress in Physalis alkekengi: Synergistic Effects of Foliar Boron and Zinc on Photosynthesis and Metabolite Accumulation 409 413 135271 10.22034/jmpb.2026.371603.2114 EN Warqaa Muhammed Shariff Al-Sheikh Faculty of Basic Science Branch, Faculty of Dentistry, University of Al-Qadisiyah Heidar Meftahizade Department of Horticultural Sciences, Faculty of Agriculture & Natural Resources, Ardakan University, Ardakan, Iran Journal Article 2025 12 01 This study investigated the effects of foliar boron (B) and zinc (Zn) on <em>Physalis alkekengi</em> under four levels of drought stress (0%, 25%, 50%, and 75% of field capacity). Plants were treated with B at 0, 100, 200, and 400 ml/L and Zn at 0, 1, 2, and 3 g/L. Drought stress significantly reduced fruit length (3.5–5.2 cm), weight (13.7–22.8 g), and firmness (1.7–3.5 N). The combined foliar application of B (200 ml/L) and Zn (2 g/L) under moderate drought (50% field capacity) produced the best outcomes. Fruit weight increased by 28%, total soluble solids (TSS) reached 11.6%, chlorophyll content rose to 2.1 mg/g FW, and photosystem II efficiency (Fv/Fm) improved to 0.78. Total phenolics (7.2 mg/g FW), flavonoids (32.3 mg/g FW), and proline (38.5 mg/g FW) also peaked under this treatment, indicating enhanced antioxidant metabolism and osmotic adjustment. Strong correlations were observed between proline and total phenolics (r = 0.90), and between flavonoids and total phenolics (r = 0.86), suggesting coordinated stress-response mechanisms. Principal component analysis (PCA) revealed clear clustering of treatments, separating those with higher fruit quality and metabolite accumulation from treatments with improved photosynthetic efficiency. Overall, foliar B and Zn acted synergistically to alleviate drought stress, stabilize photosynthesis, enhance antioxidant defenses, and improve fruit growth and quality in <em>P. alkekengi</em>. These findings demonstrate that integrated micronutrient management can be an effective strategy to improve plant performance under water-limited conditions, benefiting both productivity and the nutritional value of fruits. https://jmpb.areeo.ac.ir/article_135271_1fe0e609b8117ea60279716e0484d6a4.pdf