Sweet Success: Unraveling the Role of Root and Shoot Sugar Dynamics in Brinjal's Short-Term Salinity Stress Resilience

Growth and productivity of brinjal (Solanum melongena L.) are significantly impacted by salinity stress, a prominent abiotic factor. The present study we investigated the influence of short-term salinity stress in three brinjal genotypes exhibiting diverse responses to salinity stress. The study reveals that salinity stress significantly affected root and shoot length, susceptible genotype Solanum melongena var insanum displayed the smallest increase, while the tolerant genotype B-BR-54 showed comparable values to control conditions for shoot and root length. Further, the salinity stress significantly decreased the photosynthetic efficiency of plants and thereby reducing the growth rate in the susceptible genotype Solanum melongena var insanum, while the tolerant genotype B-BR-54 maintained higher photosynthetic rate and growth rates during salt stress period. The tolerant genotype B-BR-54 exhibited lower malondialdehyde content along with higher superoxide dismutase and peroxidase activity throughout the stress period. On contrast the susceptible genotype Solanum melongena var insanum had higher lipid peroxidation that can be explained by lower antioxidant enzyme activity under stress condition. The quantitative estimation of eleven sugar molecules indicated a differential accumulation pattern between the tolerant B-BR-54 and susceptible Solanum melongena var insanum for xylose, sucrose, rhamnose, mannose, and fucose in roots and sorbitol, ribose, glucose, mannose, fucose, and inositol in leaves. These sugars have a specific role in energy metabolism, osmotic adjustment, and signaling under salinity stress. These findings provide an initial insight into the differential responses in root and leaf sugar metabolism highlighting the importance of sugar metabolism in mediating salinity stress tolerance in brinjal.