Role of gibberellic acid (GA ₄ ₊ ₇ ) in mitigating chromium (Cr ⁶⁺ ) stress in wheat: physiological and in-silico evidence

The toxicity of chromium (Cr6+) is a major environmental constraint that impairs wheat growth by disrupting cellular homeostasis and metabolism. The present study aimed to evaluate the ameliorative effect of gibberellic acid (GA4 + 7) against Cr6+-induced stress in wheat. The experiment was designed as a 3 × 3 factorial completely randomized design with 3 stress levels of chromium (S0 (0 mg kg−1 Cr6+), S1 (50 mg kg−1 Cr6+), S2 (100 mg kg−1 Cr6+)) and 3 levels of GA4+7 (0%, 0.01%, 0.02% (v/v) foliar application). Significant reduction in growth, physiological, and yield-related characteristics was observed in stressed plants. However, GA4 + 7 application increased the membrane stability by 7–10%, reduced the electrolyte leakage by 15–18%, and increased the relative water content by 6–8%. In severe chromium stress (S2), GA4 + 7 application improved chlorophyll content, membrane stability index, and relative water content, by 33.4%, 6.5%, and 3.9%, respectively, while electrolyte leakage was reduced by 5.1%. Relative to untreated chromium-stressed plants, GA4 + 7 application increased plant yield by up to 22%, partially compensating for chromium-induced yield losses. The results indicate that GA4 + 7 has the potential to reduce Cr toxicity in wheat, but larger-scale trials are needed. Molecular docking of Arabidopsis DELLA protein with gibberellin receptor is exploratory evidence rather than supportive.