An integrated assessment of seed germination performance using classical and complementary metrics under abiotic...

Seed germination is a critical phase strongly affected by abiotic stresses including drought and artificial seed ageing. Traditional indices like Germination Percentage (GP) and Mean Germination Time (MGT) often fail to capture complex stress responses and priming efficacy. This study introduces eight novel indices that quantitatively measure distinct physiological mechanisms: The Priming Efficiency Index (SPEI), Stress Performance Stability Index (SPSI), Germination Recovery Ratio (SGRR), and Combined Vigor Index (SCVI), among others. Tested on wheat under drought stress and priming treatments, the indices demonstrated 34.2% improvement in germination recovery with gibberellin priming compared to 25.8% with hydro-priming. The SCVI showed a 20.7% enhancement in integrated seedling performance, while SGRR achieved complete stress recovery (1.004) with gibberellin treatment. Validation across triticale and pumpkin revealed consistent performance, with cross-species correlations exceeding 0.89. Statistical analyses confirmed the novel indices' superior discriminatory power, requiring 37.6% smaller sample sizes than traditional metrics while maintaining 94% rank stability under data perturbations. These indices provide robust, mechanistically informed tools for precision phenotyping in breeding programs and seed technology research.