| The fruits of Atriplex micrantha C. A. Mey. have dimorphism. The fruits (seeds) of Atriplex micrantha were germinated for 15 d in incubators with a 12 h photoperiod and 12 h thermoperiods (dark / light) of 5/15℃, 5/25℃and 15/25℃. The mature brown seed can germinate in the 3 thermoperiods, and the germination percentage and germination index of seeds is the highest at 5/25℃(dark / light). Low night (5°C) and high day (25°C) temperature regimes showed higher germination for black seeds, while at 5 / 15℃;15 / 25℃, germination percentage is low (<20%). Black seeds have non-deep physiological dormancy; they germinate slowly and to a low percentage. Two weeks of cold stratification, scarification of covering layers (pericarp and seed coat) can increase seed germination percentage and rate. The salt concentration in bracteoles of freshly ripened fruits is too low to mediate an inhibitory effect on germination of brown seed. After the fruits (seeds) of Atriplex micrantha stored for 12m, the germination percentage increased.The effects of different salts stresses on the seed germination of A. micrantha were studied. The results show the germination percentage and rate decreased as salinity increased and optimal germination was obtained in distilled water. Germination of brown seed fell to 0 at 2.0mol/L, and the black seed could not germinate at 0.4mol/L. The salinity tolerance of brown seed is better. Seeds which were incubated in NaCl solution for 20d recovered after being transferred to distilled water and the germination percentage of recovery from high salinity concentrations was higher than low concentrations. In high salinity (4mol/L NaCl ), the percentage of recovery of black seed can achieve 84%, while brown seed only 46%. The chief influence of high salinity is primarily osmotic to black seeds, but it may be a combination of ion toxicity and primarily osmotic to brown seeds.It is found the fruit of Atriplex aucheri is heterocarpy. It has three types fruits that are different in shape,size,color of seed and size of bracts attached fruits.The seeds of Atriplex aucheri were germinated for 50 d in incubators at three thermoperiods. The mature type C seed can germinate, The germination percentage of Type C seed is the best at 5 : 25℃(dark : light). Type A and type B had non-deep physiological dormancy, they germinate slowly and to a low percentage. Rate and percentage of germination of type A seed and type B can be increased by scarifying the fruit coat and 12-16 weeks cold stratification or blow 0℃stratification. Type A and type B stored for 3a, and the germination were up to 48% and 58%. While type C could not germinate after storing for above 2a. The salt concentration in bracteoles of freshly ripened fruits can inhibit the type C. The chief influence of bracteoles is primarily osmotic effect. Swashing and soaking can relieve the inhibitory effect. Type C seeds were germinated at various salinity ( 0~4mol/L NaCl ). The results indicate the germination and germination of recovery of type C decreased by NaCl at higher concentrations. The chief effect of low salinity is primarily osmotic, and the high salinity due to a specific ion toxicity.
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