| The small shrubs Atriplex cana C. A. Mey and Atriplex verrucifera Bieb grow in saline deserts in northwest China. The seed germination ecology of the two species was studied in the paper.The research aspects include: (1) Effect of temperature, bracts and store condition on seed germination. (2) Effect of NaCl concentration on seed germination and germination recovery. (3) Effect of NaCl on seedling elongation and elongation recovery after seedings were transferred to distilled water.The freshly matured seeds of A.cana and A.verrucifera have non-deep physiological dormancy. They need 2 and 8 weeks of cold stratification to break the dormancy respectively. After the dormancy had been broken, the optimal condition for seed germination of A.cana is at day/night =15/5℃, A.verrucifera is at day/night = 25/15℃. The bracts inhibited germination of freshly matured seeds of A.cana by mechanical effect,the effect of mechanical effect decreased after cold stratification; the germination time of freshly matured seeds of A. verrucifera was enlonged by bracts, but the final germination didn't changed significantly. After 2 weeks cold stratification, the germination of A.cana seeds reached the top, but after 8 weeks, seeds lost vitality; the germination of A.verrucifera was increased with the cold stratification, and reached maximum after 8 weeks cold stratification. The seeds germination and the germination speed of A.cana and A.verrucifera increased gradually with the store time under normal condition.The responses of the seeds of the two species to NaCl concentration were different. The germination of A.cana decreased with the increase of salinity and was hightest at distilled water. The germination of A.verrucifera was hightest at 0.2M NaCl and decreased when the concentration of NaCl>0.2M. In the end, the salinities to completely inhibit germination were 1.2 and 0.8MNaCl respectively. When the ungerminated seeds were transferred into distilled water, they can continue to germinate. The recovery percentage of A.cana was highest in 1.0MNaCl, but final germination was highest in non-saline control. While the recovery percentages of A.verrucifera from 3.0MNaCl were all above 75%, and the finale germination percentage was higher than percentage in control. The result indicated that NaCl inhibited germination by osmotic stress.The growth of buds and boots of early seedlings of A. cana were promoted in low concentration(0.2M NaCl), the ratio of root to shoot reached the top.The prolonging of seedlings were inhibited as the concentration≥0.4M, the salt concentrations had more influence on the radicle, and ratio of root to shoot gradually decreased and with the increase of salinity seedling growth was inhibted finally(1.0M NaCl). However NaCl (<0.2M) didn't effect the growth of scions and radicles of early seedlings of A.verrucifera. The growth was inhibited gradually and ratio of root to shoot decreaded with the increase of the salt. In the end, seedling elongation was completely inhibited by≥0.8MNaCl. Elongation of radicles and scions resumed after seedlings were transferred to distilled water, and their ability to continue elongating decreased with increase in pretreatment concentration of NaCl. The growing ability of radicles was biger than scions. A.verrucifera pretreated by NaCl≥0.8M and that of A.cana pretreated byNaCl concentrations≥1.0M could not grow any more.The results showed that the seed germination and the early growth stages of seedlings of the two species can be adaptable to saline environment. The ability of seeds and seedlings that maintain regerminating and regrowing under high salt stress is one of the special adaptive strategies for them to inhabit the salt desert environment. Those can help them survive and reproduce successfully in the salt desert of Xinjiang.
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