Development of a Silicon Efficiency Index Integrated with GGE Biplot Analysis for Identifying Salinity-tolerant Wheat Genotypes

Abstract Salinity stress severely limits wheat production globally, necessitating the development of salt-tolerant genotypes with enhanced resilience mechanisms. Silicon (Si), an emerging beneficial element, promise for mitigating salinity effect through modulation of physiological and biochemical processes. This study developed and validated a novel Silicon Efficiency Index (SEI) to quantify genotype-specific Si responsiveness and integrated it with GGE biplot analysis to identify wheat genotypes combining salinity tolerance with Si efficiency. Twenty-two diverse wheat genotypes were evaluated at the seedling stage under three treatments: control (T0), salinity stress (T1: 150 mM NaCl) and salinity stress with Si supplementation (T2: 150 mM NaCl + 1mM Si) in a completely randomized design with three replications. Salinity stress significantly reduced seedling vigour index (20.3%), shoot and root biomass (14–15%), chlorophyll contents (up to 50%), and antioxidant enzymes activities (SOD, POD, CAT), alongside decreased total soluble proteins. Si supplementation effectively mitigated these reductions, improving morphological, physiological and biochemical traits. GGE biplot analysis identified G04, G17, G16 and G06 as superior genotypes with broad adaptability and stability across environments. G16 exhibited optimal performance under salinity stress, while G15 and G17 excelled under control and Si-supplemented conditions. The newly developed SEI provided complementary trait-specific quantification of Si responsiveness, highlighting G04, G06, and G16 as highly Si-efficient genotypes. Integration of both GGE biplot and SEI analyses consistently identified G04, G06, G17, and G16 as dual performing genotypes, combining environmental adaptability, stability and Si efficiency. These genotypes represent robust candidates for breeding programs and cultivation strategies in saline environments. The SEI methodology provides a valuable tool for screening Si-responsive genotypes and can be adapted for other crops and stress conditions, advancing precision breeding for sustainable agriculture under challenging environments. Highlights Salinity stress reduced growth, pigments, proteins, and antioxidant activity in wheat. Silicon supplementation mitigated salinity effects and improved physiological and biochemical resilience. Introduced a novel Silicon Efficiency Index (SEI) for stress-resilient genotype selection. Integration of SEI with GGE biplot supports climate-smart genotype selection. SEI provides a sustainability-oriented tool for resilient agroecosystem management.