Abstract:

【Objective】 Physiological effects of seed priming on salt resistance of sorghum seedlings were studied in this paper. 【Method】 Four sorghum hybrids seeds (Tiansi No. 1, Tx623A×89-363, Hei 30A×05-244 and Jinza 17) were soaked in 100 mmol?L-1 NaCl and 20%PEG solutions. Different degrees of salt injury were simulated with 0, 50, 100 and 150 mmol?L-1 NaCl solution by methods of nutritional sand culture. After seeds priming, germination conditions, salt resistance and physiological effects on seedlings were studied. 【Result】 Priming treatment enhanced the tolerance index and tolerance ratio to some degree. At the same time, the germination potential, germination rate, germination index and activity index were improved obviously, especially for the NaCl priming. In the course of stress of 100 mmol?L-1 NaCl solution, in particular the late stress, NaCl priming reduced MDA contents, enhanced SOD activities, contents of proline and soluble proteins in sorghum seedlings. 【Conclusion】 Seed priming technology could enhance the salt tolerance of sorghum seedlings which solved the problem of low germination rate and saving seedling rate in saline soil. The salt tolerance of sorghum seedlings was improved by increasing the activities of protective enzymes and contents of osmotic adjustment substances under the condition of salt stress.

Key words: sorghum, seed priming, NaCl stress, salt resistance