Salinity tolerance dynamics in selected crop species at germination stage under in vitro and in situ conditions in Patuakhali, Bangladesh

Salinity is a major abiotic stress limiting crop productivity, predominantly in coastal regions. This study aimed to evaluate the salinity tolerance of selected crop species at the germination stage under both in vitro (petri dishes) and in situ (pot culture) conditions. The main research question was to identify crop species capable of tolerating different salinity levels and to assess their physiological and ionic responses for suitability in saline coastal regions of Bangladesh. Fourteen crop species from pulse, vegetable, fodder, and fibrous groups were tested under salinity levels of 0, 4.50, 8.65, and 13.07 dS m⁻¹ in petri dishes. Parameters measured included germination percentage (GP), shoot and root length, fresh and dry weight, salinity tolerance index (TI), sensitivity index (SI), and Na + : K + . The five best-performing species in petri dishes were further evaluated in pot culture using saline soil (0.73–15.42 dS m⁻¹). Statistical analyses were conducted using ANOVA and Tukey’s test to determine the significance differences among the treatments. Germination generally decreased with increasing salinity, though snake bean and millet performed better at moderate levels. Five species showed GP > 80% in vitro, while in situ results exceeded 87%. Snake bean, cucumber, and gima kalmi were salt-tolerant up to 8.65 dS m⁻¹, while mung bean, jute, and kenaf were moderately tolerant. However, low control germination of millet limits confidence in salinity tolerance classification. A balanced Na + : K + contributed to higher tolerance. Snake bean, cucumber, and gima kalmi are promising salt-tolerant crops, while several others show moderate tolerance. These findings provide preliminary evidence for prioritizing candidate crops for further field-based evaluation and adaptation strategies in saline coastal regions of Bangladesh.