| As the fast development of city greening, most potential ornamental trees are needed to exploit to satisfy the request of city plants-diversity. Tamarix chinensis Lour. is widely distributed in China. It has thin and reddish twigs, numerous and scale-Iike leaves, pink to whitish flowers. Especially it can tolerate drought and wet environment, also can grow in very alkaline and saline soils and maritime exposure. It will have a bright future in the landscape using. The distribution of Tamarix chinensis was investigated clearly in this paper. And on this basis, the collection of provenances, propagation technology, seedling primary selection,cuttings rooting anatomical observation were studied. At the same time, growing phenology of the provenance from Qinghai Ping'an in xining was observed. The growth rhythm of one-year cutting seedlings, cultivation types and application future were studied too. The main results are as follows:i) Germ-materials of 10 provenances were collected from Jianzha, Hualong Minhe, Ping'an, Datong, Menyuan, Delingha, Gonghe, Guinan, and Xinghai. A primary resource pool was built in Ping'an in Qinghai province. The steps of central germplasm of Tamarix chinensis were set down.ii ) In cutting experiments, there were no obvious difference between different provenances in cuttings'rooting ability. But the thickness of cuttings, treatment time by auxin and auxin's concentration had obvious effects on rooting. The best union of experiment should be A4B2C4D2, viz the thickness of cutting was more than 1.1 cm, and then drenched in 200ppm IBA auxin for 9 hours. There were no differences between cutting in materials pool and in field, but generally speaking, the later had more advantages. Two years old twigs could be used to cut in spring, summer and autumn, the rooting ratio could reach to 95 percent. If the cutting pool was covered by plastic films, annual twigs could be used as cutting in winter too.iii) After one-year growth, there was remarkable difference among the height growth of ten provenances, but the caliper growth was almost the same. Three priority provenances just as Qinghai Gonghe,Minhe,Ping'an and 17 superior seedlings which have excellent traits were selected.iv) The growing phenological period of Qinghai Ping'an was 260 days. Leaves can keep green in about 210 days. Flowers bloom in spring and summer, and the total flowering time is nearly 90days. Annual growth rhythm of height on one-year cutting seedlings is fitted for S curve and growth period is 150 days, the net growth volume is 76.5 cm. The growth period of caliper is 120 days and the net growth volume is 3.2 mm. The main roots and lateral roots of one-year cutting seedlings are very well developed too. The average diameter of root is 42.3cm and the average length of main root 37.8cm, with the roots mostly distributed in the surface layer of 0-30cm underground. Fresh weight distribution ratio of aboveground to underground is 3.14.v) Tamarix chinensis could be able to endure intensive trimming and performed good regenerating ability. Five types of trimming were put forward according to Tamarix chinensis biological characteristics and future use for landscape architecture was also probed.
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