Seeds Priming with Gibberellic Acid Enhances Germination and Early Seedling Growth under Salinity Stress in Maize ( Zea Mays L.)

A gibberellic acid priming study was conducted at laboratory conditions of Khulna University, Bangladesh, using the maize variety, ‘BARI Hybrid Bhutta-16’, during 2021. The treatments consisted of four salinity levels with electrical conductivities (ECs) of 0, 10, 20, and 30 dS/m, combined with three GA 3 concentrations (0, 100 and 150 ppm). Salinity stress significantly impaired germination percentage, germination energy, and germination speed, as well as root and shoot development, particularly at salinity levels exceeding EC of 10 dS/m. GA 3 application improved seedling growth across salinity levels, with 100 and 150 ppm concentrations showing the most notable effects under EC of 10 dS/m. Root and shoot lengths, fresh and dry biomass, and seedling vigour index were enhanced by GA 3 treatment, especially at EC of 0 – 10 dS/m. However, at ECs of 20 and 30 dS/m, GA 3 failed to significantly improve most of the parameters, indicating a threshold beyond which salt stress overrides hormonal benefits. GA 3 priming enhances maize germination and early seedling growth under moderate salinity but shows limited efficacy under severe stress.