| Salsola affinis, Atriplex aucheri, Atriplex micrantha, dominant annual, are mainly distributed in deserts of the Junggar Basin, China. Its have two or three types of fruits that differ in shape, size, seed colour. Its were studied about the fruit and seed characteristics and germination behavior. The main results were as follows:1. Salsola affinis C. A. Meyer, a dominant annual, is mainly distributed in deserts of the Junggar Basin, China. S. affinis has three types of fruits that differ in shape, size, seed colour, and size of wings on the fruits. Type A fruits have lignified tepals with long wings and green seeds, can be easily dispersed by wind to a far distance from the mother plant. Type B fruits have lignified tepals with short wings or no wings and green seeds, and attach tightly to the mother plant. Type C fruits have tepals without wings and yellow seeds, and also attach tightly to the mother plant. Freshly harvested type A or type B seeds can germinate in a wide temperature regimes range from 5 to 30°C in light or darkness. Rate and final percentages of germination of type B seeds are higher than that of type A seeds. Type C seeds have nondeep physiological dormancy because germination is slow and low. Cold stratification, scarification on the seed coat or treating the seed with KNO3 can hasten and increase the seed germination.In Salsola affinis natural population, different individuals have significant difference in plant weight, plant height, the number of branch class and node.Three type fruits are significant change in the different size plant. The ratio of type A and B fruits varieties apparently with the increase of individual size, and the ratio of type C fruits is steady. The total number of seed increases accompany with the increase of the size of plant. There are significant changes among the ratio of three type fruits, which changes from 1:153.02:79.35 to 2.83:1:1.71.With increased individual size, plant has stable total reproductive allocation, but the reproductive allocation ratio increases for reproduction units A, ratio decreases for reproduction units B, reproduction units C has stable allocation with the increase of the size of plant.There are different dispersal mechanisms in three different type fruits. Type A fruits can be easily removed and dispersed to far distance by wind, because the persistent perianth of type A fruits has a crimson red wing-shaped attachment on the dorsal side; type B and C fruits can only dispersed near the mother plant, because the persistent perianth have no wing (or short wing) and can not easily removed from the mother plant.Experiments were conducted to determine the effects of wing and NaCl on Type A seed germination and their recovery of germination from saline conditions after being transferred to distilled water. Attached winged perianths inhibited seeds germination. Winged perianths formed a mechanical barrier to seed germination, and they required to be removed to enhance germination.Germination was not affected by NaCl at concentrations below 0.4mol/L, and was decreased by NaCl at higher concentrations. Increases in NaCl concentration progressively inhibited seed germination. few seeds germination at 1.4mol/L NaCl. Rate of germination decreased with an increase in salinity. Seeds that were incubated in NaCl solution for 12 d recovered after being transferred to distilled water and the percentage of recovery was higher, but lower than the non-saline control, indicating that parts of the NaCl treated seeds have permanently lost their germination ability.2. The observation on fruit and seed of Atriplex aucheri have been made. It is found the fruit of A. aucheri is heterocarpy. It has three type fruits that are different in shape, size, color of seed and size of bracts attached fruits. Type A fruits are produced by female bracteate flowers but its achenes are brown and rather large covered by extended bracteoles that are bigger than those of type B fruit. Type B fruits are also produced by female bracteate flowers. Although its achenes are larger than type C, they have a similar appearance, but are covered by extended bracteoles. Type C fruits originate from bisexual ebracteate flowers and consist of small, black, lens-shaped achenes enclosed within a 5-lobed perianth. The mature type A seed can germinate. The germination percentage of type C seed is the best at 5℃/25℃. Type B and type C had non-deep physiological dormancy, they germinate slowly and to a low percentage. Rate and percentage of germination of type B seed and Type C can be increased by scarifying the fruit coat and cold stratification.The bracteole can inhibit germination of brown seed. The bracteoles contain mainly Cl~- and Na~+. So the osmotic potential of soluble ion bracteoles is lower. It is suggested bracteole inhibit germination via ionic effects.3. The fruit and seed characteristics were observed on Atriplex micrantha from Junggar desert. It is found the fruits of Atriplex micrantha have dimorphism. It has two types of fruits that are different in shape, size, color of seeds and size of bracts attached fruits. Small, black, lens-shaped achenes with a glossy, smooth testa are covered by extended bracteoles. Brown achenes are rather large and covered by extended bracteoles that are bigger. The fruits (seeds) of Atriplex micrantha were germinated for 15 d in incubators with a 12 h photoperiod and 12 h thermoperiodsof 5℃/15℃, 5℃/25℃and 15℃/25℃. The mature brown seed can germinate in the 3 thermoperiods, and the germination percentage and germination rate of seeds is the highest at 5℃/25℃(dark/light). Low night (5℃) and high day (25°C) temperature regimes showed higher germination for black seeds, while at 5℃/15℃and 15℃/25℃, germination percentage was 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 germination rate.The salt concentration in bracteoles of freshly ripened fruits is too low to mediate an inhibitory effect on germination of brown seed.Utricle polymorphism may allow Salsola affinis, Atriplex aucheri, Atriplex micrantha to respond to spatial and temporal variations in environmental conditions, thus increasing the chances for survival of this annual species in its harsh desert habitats.
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