The Effect of Saline Stress on the Germination and Embryo Growth of Three Saline-Grass Seeds

Solutions of various concentration of NaCl,Na2CO3,and a mixture of the two were used for saline stress to measure and analyse the seed germination percentage and speed,and the growth of radical and plumule of three saline grasses- Leymus chinensis,Hordeum brevisubulatum, and Puccinellia chinampoensis -by saturating the seeds and then allaying the saline stress.The result shows that the L.chinensis and H.brevisubulatum seeds' germination percentage and speed,and the growth of radical and plumule,in comparison,reduced with the strengthening of the salt concentration of Na2CO3,and the NaCl and Na2CO3 mixture.However,the P.chinampoensis seed germination percentage,and the growth of radical and plumule mounted and developed under the stress of low salt concentration of 12.5 mmol/L NaCl and 37.5 mmol/L Na~+,but its seed germination speed diminished with the intensifying of the salt concentration.The Na2CO3 solution restrained all the three saline grasses' radical and plumule growth.The salt stress of all the three solutions declined the growth of readicals of L.chinensis and P.chinampoensis more markedly than the growth of their plumules.The salt tolerance of P.chinampoensis seed during germination surpassed that of L.chinensis and of H.brevisubulatum in the same period.After allaying the salt stress,the three saline grasses'seed germination rate increased basically with the increase of pre-treatment salt concentration.