Background: Soil salinity is an increasing problem in the world and the main obstacle to agricultural productivity especially in areas where irrigation is necessary. Adoption of salt tolerant genotype is more important here and so screening of salt tolerant cultivars is essential. For that, quick method to screen salt-tolerant plants, particularly in early stages of their growth is important. Methodology: For this purpose, some laboratory studies using nine sorghum genotypes were conducted to screen salt tolerant genotypes during germination and seedling growth stages. The genotypes were Hybrid sorgo, Debgiri, BD 703, BD 706, BD 707, BD 713, BD 720, BD 725 and BD 738 and salinity levels were 0 dSm-1 (control), 6 dSm-1, 12 dSm-1 and 18 dSm-1. There were 36 (9×4) treatments in a completely randomized design (CRD) with three replications. Saline treatments were imposed by sea water solution. To screen out the salt-tolerant genotypes germination percentage, rate of germination, vigor index and different physiological parameters i.e. germination stress tolerance index (GSTI), root length stress tolerance index (RLSI), shoot length stress tolerance index (SLSI) and fresh weight stress tolerance index (FSTI) were studied. Key findings: In this study, all the parameters were decreased with increasing salinity. On the basis of the results obtained using above mentioned germination and physiological criteria, sorghum genotypes Hybrid sorgo, BD 703 & BD 707 were categorized as tolerant while Debgiri and BD 713 were found as sensitive ones. Besides these, sorghum genotypes were not tolerant up to 18dSm-1 though some of them were tolerant at 12dSm-1. Conclusion: Overall, these tolerant and sensitive genotypes might be used in the further genetic improvement of the same and different crops.
Key words: Sorghum, Cereal, Salinity, Osmotic stress, Sea water, Physiological indices
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