Study On The Biological Characteristics And Landscape Evaluation Of Four Species Of Caragana L. In Xinjiang

Caragana Fabr. belongs to Leguminosae,Xinjiang is the place with abundent species diversity of Caragana both in China and in the world.In this article,native species to Xinjiang Caragana leucophloea Pojark.,Caragana aurantiaca Koehne.,Caragana soongorica Grub.,Caragana acanthophylla Kom. Were studied from the following aspects:seed propagation,cutting propagation,seed and seedling salt stress,landscape viewing characteristics.After field investigations,indoor seed germination experiment and outdoor potted plants experiment,data processing,the following conclusions were obtained:(1)The experiments of seed germination showed that C. aurantiaca Koehne and C.leucophloea Pojark seeds have high germination rate.Characteristics of seed germination and seedling emergence are almost similar.The seed germination and seedling emergence of C. aurantiaca Koehne. is rapid and concentrative while C. leucophloea Pojark slow and steady. Both the germination rate and index of C. soongorica Grub are low.(2)Cutting experiments show that these three Caragana Fabr. species used in experiment are difficult to root.Although cutting rootability can be improved by using different concentrations ABT1,it is still too low. C. leucophloea Pojark. gets the highest rootability (18.5%) by soaking in 100mg/L Baptist six and a half hours;C. acanthophylla Kom gets the highest rootability (9.5%) by dipping fast in 500mg/L ABT1 for five to ten seconds;C. soongorica Grub reaches the highest rootability (3%) by dipping fast in 1000mg/L ABT1 for five to ten seconds. Different treatment method affect the rootability of Caragana obviously,not rootability by dipping fast in low concentrations.(3)The experiment of dormnancy breakage shows that soak C. acanthophylla Kom and C. soongorica Grub. soaking in different concentrations of gibberellin acid,it shows that a 24-hour soaking is better than 48 hours,there exists obvious differences with other treatments if soak C. soongorica Grub in 500mg/L gibberellin for 24-hour;it is significant different from other treatments if soak C. acanthophylla Kom in concentration of 1000mg/L gibberellin for 24-hour and its germination rate is 97%;cold stratification can accelerate to break seed dormancy of these two species,both germination rate and index were improved,3-5℃stratification can break seed dormancy the most.(4)Salt stress experiments showed that different concentrations of NaCl stress inhibted the seed germination of C. leucophloea Pojark. and C. aurantiaca Koehne..Seed germination rate decreased with the increase of NaCl stress concentration and the highest germination rate was get in the control;different concentrations of NaCl stress affected the of theconductance ratio,MDA content,content of proline of two Caragana species.Three physiological indicators showed that C. leucophloea. has higher salt stress ability than C. aurantiaca.(5)Four species of Caragana L. in Xinjiang from the ornamental value of plants is evaluated in landscaping and the prospects of development.It concludes that Caragana Fabr. plants in Xinjiang has good prospects in development potential and market.