impact of salinity on tomato seedling development: a comparative study of germination and growth dynamics in different cultivars

Soil salinity is an escalating problem that significantly reduces crop yield, particularly in regions with intensive agriculture or poor irrigation practices. this study aimed to assess the impact of salinity on the germination and early growth parameters of four tomato (solanum lycopersicum) cultivars: 'sakata', 'us-agriseed', 'rossen b.v.', and 'supermarmance'. methods: the experiment was conducted under controlled greenhouse conditions with a randomized complete block design. seeds were exposed to five salinity treatments (0, 4, 6, 8, and 10 ds m^-1), and growth parameters including germination rate, seedling length, leaf number, and wet and dry weights were measured over a two-week period. the results demonstrated that increasing salinity levels had a significant inhibitory effect on all measured growth parameters across all cultivars. germination rates and seedling vigor decreased with increasing salinity, and a complete inhibition of growth was observed at the highest salinity levels (ec-8 and ec-10). however, variability among cultivars indicated differential salinity tolerance, with 'us-agriseed' displaying relatively better performance under saline conditions. the study provides clear evidence that salinity levels as low as 4 ds m^-1 can adversely affect the germination and seedling growth of tomato plants. the findings highlight the critical need for developing salinity management strategies and breeding programs to improve salinity tolerance in tomatoes, which could significantly mitigate the impact of salinity stress on crop productivity.