| Hippophae rhamnoides subsp. sinensis is drought tolerant perennial shrub, and endemic species to China , which has a value of significant officinal ,edible, and preserve soil and water. It is distributed from the edge of the Qinghai-Tibet placteau to Hebei. The former research of the genetic diversity about H. rhamnoides subsp. sinensis, showed higher level genetic variation within populations than among populations. In the present study, we observed the character of flower and habit in blossom out, measured the distance of pollen spread,examined the stigma receptivity, observed and registerd the species of frugivorous birds and the ways of frugivorous birds handle the fruits, collected the feces of birds, test pollen viability and pollen germination ratio , compared with seeds germination experiment etc..By observing and analysing the sex ratio, pollen flow and seed flow and researching on the approach of gene flow within populations and among populations, it provided the theoretical basis for future reseach on the change of H, rhamnoides subsp. sinensis populations genetic structure. The mostly results are as follows:1.Sex ratio of 9 populations were conducted,and the results showed that the change of female and male ratio were depend on enviornment,which varied from 7:2 to 1:7. On the whole, male individual is enough for female individual to be pollinated .2.Flower strcuture of H. rhamnoides subsp.sinensis was simple.The time of flowering was at the last ten days of April or the first ten days of May and can retain flowering about a week. Just the flowering of male flower , sepal dehisced from two sides,then the dehiscence increasing litter by litter,and the great deal of pollen were spread by wind,at last, the joint of sepal dehisced while pollen all spread, meanwhile,male flower withered. At the first 1 to 2 day of the flowering of female flower, stigma was kelly.With stigma being albescent bit by bit,it was the right time for pollinations. After been pollinated,the stigma gradually change into dark. The pollen viability and germination ratio were tested in 24h,the results showed that the mean viability was 52. 3% and 70. 8% at initial stages of flowering and anaphase of flowering,and the mean of germination ratio was 39.4% and 57. 5% , respectively. The distance of pollen spread was determined by temperature, humidity,and the strength of sunlight etc.. Dring the phase of pollination , there were most pollen in atmosphere at the middle 3 days of blooming date. The spread distance of pollen with the direction wind were about 100m. In one day, the most pollen were spread during 11:30 to 15:30.3. The type of fruits of H. rhamnoides subsp. sinensis were diversity, 18 species of birds eating fruits of H. rhamnoides subsp. Sinensis were observed such as Streptopelia decaocto, Cyanopica cyana, Pica pica, Garrulus glandarius, Corvus macrorhynchus, Phoenicurus erthrogaster , Turdus ruficois etc..Their frugivorous ways were found to be various: ①directly swallowing the fruits on crown of the shrubs and sometimes regurgitating seeds soon after; ②carrying the fruits to other places around from the shrubs and then swallowing the fruits at their perching sites; ③pecking the fruits from the shrubs to the ground, and then eating pulp and seeds but leaving pericarp; ④ pecking through the pericarp on the top of fruits, and only eating seeds, ⑤pecking through the pericarp, eating pulp and leaving pericarp and seeds.4. Compared experiment of seeds germination (seeds from feces, dry fruits and extracted seeds dry fruits) , showed that the seeds from feces had a relative higher germination ratio. The germination ratio of seeds without endocarp from feces were 38. 3 ± 3. 8% and seeds with endocarp from feces were 27. 3 ± 4. l%;while germination of seeds without endocarp were earlier 2~3 days than seed with endocarp.Based on those results, we can concluded that the genetic variation is higher within populations than among them, which mainly caused by long distance dispersal of seed ,and the spread distance of pollen were limited...
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