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Salt and harmful ions in the saline-alkali soil barrier of normal growth of plants, most plants can not grow normally. In recent years, scholars from various countries putting forward proposals to achieve the purpose of the use of improved saline-alkali soil biological adaptation to the environment, breeding Saline Soil. The use of salt-tolerant plants improved saline-alkali soil improvement and utilization of the model, a recovery of vegetation can improve the adverse environment of saline-alkali land area, improve soil fertility, promote the development of the region through the development and utilization of these salt-tolerant plants, good ecological and economic benefits. Typically used saline land green garden plants can be broadly divided into: the native halophytes screening after people with some salt tolerance garden plants two categories. But for now, a single plant varieties for saline areas of urban greening, with the value of urban greening and beautification of plant resources is quite poor, greatly restricting the construction of a modern urban ecological green system. In this study, preparation of coastal saline soil cultivation soil, greenhouse pot method, the study of 15 common landscaping plant salt tolerance. 15 species planted in 2 batches under different salinity treatment: (1) Forsythia (Forsythia suspense (Thunb.) Vahl), rose (Rosa Chinensis Jacq.) Osmanthusfragrans (Osmanthus fragrans cv.Semperflo), gold leaf female Zhen (the Ligustrum vicaryi Ait.), climb to Parker (sabina procumbens (Endl.) Iwata et Kusaka), cedar (Cedrus deodara (Roxb.) G.) and Pinus tabulaeformis (of Pinus tabulaeformis Carr.), salinity: 0.91 g / kg (control treatment), 2.3g/kg, 4.6g/kg, 4.9 g / kg, 5.8 g / kg, 8.7 g / kg, 12.7 g / kg;; (2) horse chestnut (Aesculus chinensis Bunge. ) Liriodendron (of Liriodendron chinense leaves (Hemsl.) Sarg.), paste Lagenaria (Chaenomeles speciosa (Sweet) Nakai.), Kim (of Osmanthus fragrans var.thunbergii Makino), acacia (Albizzia julibrissin Durazz.) Edgeworthia (Edgeworthia chrysantha Lindl.), hackberry (Celtis sinensis Pers.) and no Sapindus (the Sapindus mukorossi Gaertn.), salinity: 0.91 g / kg (control treatment), 1.3 g / kg, 2.1 g / kg, 3.8 g / kg, 5.7 g / kg, 9.4 g / kg, 10.2 g / kg. Stress after 3 months, respectively, were observed performance of the plant growth, survival, determination of the two growth indicators (height growth and growth of base diameter), two physiological indicators (chlorophyll content and relative water content), 4 photosynthetic indicators (leaf net photosynthetic rate, stomatal conductance, intercellular CO 2 concentration and transpiration rate). Plant salt tolerance test, a comprehensive assessment, in order to filter out more with certain salt-tolerant landscaping plants, and provide a theoretical basis for the city saline-alkali soil biological improvement and saline-alkali soil resources development and utilization of the tolerance index, also lay the foundation for further breeding work. The main findings are as follows: 1. With increasing salt concentration in the the greenhouse the shoals soil of potted under the conditions, the survival and growth of the 15 kinds of garden plants are subject to varying degrees of impact. Height growth, basal diameter, leaf chlorophyll content, relative water content, leaf net photosynthetic rate and stomatal conductance changes are basic to follow: the higher the salinity, the measured value of the smaller of the law. Drop of a significant difference due to the different types of plants; intercellular CO 2 concentration With soil salinity rise upward trend: the leaf transpiration rate without consistent with the rise of soil salinity changes. 2. According to the test purpose and the actual situation, select the survival threshold indicators, combined with the growth of a variety of plant status to preliminary determine the salt tolerance of garden plants. According to this standard, the trial of the 15 kinds of garden plant salt tolerance were: (1) forsythia, rose Osmanthusfragrans three kinds of plant salt poor, and only in the salt content of less than 4.6g/kg normal growth and soil; followed by California Privet, only in the salt content is lower than the growth of a 4.9g/kg the soil: cedar in the salt content of less than 5.8g/kg soil can grow normally; P. tabulaeformis grown in soil salt content below 12.7g/kg; the salt tolerance climb to Parker, capable of growing in the soil salt content up to 12.7g/kg. (2) The poor Edgeworthia Liriodendron two salt tolerance of plants can only be grown in salt content below 1.32g/kg soil; followed by acacia and hackberry can only be grown in salt content at 2.12g/kg soil; paste Lagenaria the Kim and Sapindus species can only be grown in soil salt content lower than 3.84g/kg; Buckeyes best salt tolerance in salt the amount is less than 5.68g/kg soil growth. 3. The selected survival, height growth, basal diameter, leaf chlorophyll content and relative water content of the five indicators the tolerance index comprehensive evaluation of salt tolerance of 15 plant species, the size of the order were: (1) of Osmanthusfragrans |