Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its r...Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its rooting mechanism, cuttings of P. crassifolia with different cutting types （softwood, hardwood and root）, positions （top, upper, middle and bottom） and ages （7, 10, 15, 20, 25 year-old） were cultivated in a field experiment. One- year old softwood and hardwood cuttings were collected from 7-, 10-, 15-, 20-, and 25 year-old healthy ortets to analyze the changes from endogenous hormones and organic nutrients. Results indicate that the softwood cut- tings （0.5-1.0 cm in diameter） from upper branches of 15 year-old ortets shows better growth performance by improving rooting indexes, including a significant increasein rooting rate and a decrease in basal rot rate. Concomi- tantly, increasing rooting quantity and root length also increased. It is noteworthy that the high rooting rate of P. crassifolia cuttings due to its ability to accumulate high concentrations of indole-3-acetic acid （IAA） and total carbon （TC） rather than abscisic acid （ABA） and total nitrogen （TN）. The rooting rate was mainly regulated by the IAA/ABA and TC/TN ratio. In summary, our results suggest that the softwood cuttings （0.5-1.0 cm in diameter） from upper branches of 15 year-old P. crassifolia can be considered as an effective strategy to improve cutting rooting rate, and the IAA/ABA and TC/TN ratio was one of the main factors limiting the cutting rooting rate of P. crassifolia.展开更多
Carex brunnescens(Pers.)Poir.is considered to be the only clonal herb found to date that can develop and form fixed dunes in Maqu alpine degraded grasslands of northwestern China.However,due to strong dormant characte...Carex brunnescens(Pers.)Poir.is considered to be the only clonal herb found to date that can develop and form fixed dunes in Maqu alpine degraded grasslands of northwestern China.However,due to strong dormant characteristics of C.brunnescens seeds,the sand-fixing effect of the plant is severely limited.This study explores a technique that can rapidly promote the seed germination of C.brunnescens,and also investigates the adaptation and sand-fixing effect by cultivating C.brunnescens seedlings to establish living sand barriers in the sand ridges of moving sand dunes.Results show that the seed germination rate obtained a maximum of 63.7%or 65.1%when seeds were treated with 150 mg/L gibberellic acid(GA3)for 24 h followed by soaking in sulfuric acid(98%H2SO4)for 2.5 min or sodium hydroxide(10%NaOH)for 3.5 h,and then germinated(25°C in daytime and 5°C at nighttime)in darkness for 10 d.After breaking seed dormancy of C.brunnescens,the living sand barrier of C.brunnescens(plant spacing 15−20 cm;sand barrier spacing 10−20 m)was established in the perpendicular direction to the main wind in the middle and lower parts of the sand ridges on both sides of the moving sand dunes.When the sand ridges were leveled by wind erosion,the living sand barrier(plant spacing 15−20 cm;sand barrier spacing 0.5−1.0 m)of C.brunnescens was reestablished on the wind-eroded flat ground.Finally,a stable sand-fixing surface can be formed after connecting the living sand barriers on both sides,thus achieving a good sand-fixing effect.These findings suggest that rapid seed germination technology combined with the sand−fixing method of C.brunnescens can shorten the seed germination period and make the seedling establishment become much easier which may be an effective strategy to restore and reconstruct Maqu degraded grasslands.展开更多
We studied pot cultivated Haloxylon ammodendron＇s growth, physiological changes and drought resistance under NaC1, H2SiO3, and NaCl＋H2SiO3 treatments. Results show that 0.3 g/kg NaC1, 0.2 g/kg HzSiO3 or 0.3 g/kg NaC...We studied pot cultivated Haloxylon ammodendron＇s growth, physiological changes and drought resistance under NaC1, H2SiO3, and NaCl＋H2SiO3 treatments. Results show that 0.3 g/kg NaC1, 0.2 g/kg HzSiO3 or 0.3 g/kg NaCI＋0.1 g/kg H2SiO3 treatments can effectively promote growth and improve the drought resistance of/-L, ammodendron. Compared with that without NaCI treatment, H. ammodendron＇s height, crown diameter and fresh weight increased by 42%, 91% and 62% respectively under 0.3 g/kg NaC1 treatment, and its main stem diameter, main root diameter and main root length increased by 40%, 39% and 23%, respectively. Compared with that without H2SiO3 treatments, H. ammodendron＇s height, crown diameter and flesh weight increased by 36%, 45% and 27% respectively under 0.2 g/kg HeSiO3 treatment, and its main stem diameter, main root diameter and main root length increased by 23%, 23% and 20%, respectively. Compared with that under 0.3 g/kg NaC1 treatment, H. ammodendron＇s height, crown diameter and fresh weight and main root length increased by 9%, 10%, 17% and 12% respectively under 0.3 g/kg NaCI＋0.1 g/kg H2SiO3 treatment. Compared with that under 0.1 g/kg H2SiO3 treatment, H. ammodendron＇s height, crown diame- ter and fresh weight increased by 28%, 76% and 68% respectively under 0.3 g/kg NaCI＋0.1 g/kg H2SiO3 treatment, and its main stem diameter, main root diameter and main root length increased by 30%, 32% and 27%, respectively. This suggests that moder- ate levels of NaCI＋H2SiO3 interaction can effectively promote growth and improve drought resistance of/-L, ammodendron than separate applications of NaC1 or H2SiO3.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.31360086)the grant from the major state basic research development program of china(973 program,No.2013CB429903)
文摘Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its rooting mechanism, cuttings of P. crassifolia with different cutting types （softwood, hardwood and root）, positions （top, upper, middle and bottom） and ages （7, 10, 15, 20, 25 year-old） were cultivated in a field experiment. One- year old softwood and hardwood cuttings were collected from 7-, 10-, 15-, 20-, and 25 year-old healthy ortets to analyze the changes from endogenous hormones and organic nutrients. Results indicate that the softwood cut- tings （0.5-1.0 cm in diameter） from upper branches of 15 year-old ortets shows better growth performance by improving rooting indexes, including a significant increasein rooting rate and a decrease in basal rot rate. Concomi- tantly, increasing rooting quantity and root length also increased. It is noteworthy that the high rooting rate of P. crassifolia cuttings due to its ability to accumulate high concentrations of indole-3-acetic acid （IAA） and total carbon （TC） rather than abscisic acid （ABA） and total nitrogen （TN）. The rooting rate was mainly regulated by the IAA/ABA and TC/TN ratio. In summary, our results suggest that the softwood cuttings （0.5-1.0 cm in diameter） from upper branches of 15 year-old P. crassifolia can be considered as an effective strategy to improve cutting rooting rate, and the IAA/ABA and TC/TN ratio was one of the main factors limiting the cutting rooting rate of P. crassifolia.
基金the Project of the Youth Talent Development Fund of the Northwest Institute of Eco−Environment and ResourcesChinese Academy of Science(CAREERI)(Y851C81001)+1 种基金the National Natural Science Foundation of China(41877162)the Instrument Functional Development Project from the Technology Service Center of CAREERI(Y429C51007).
文摘Carex brunnescens(Pers.)Poir.is considered to be the only clonal herb found to date that can develop and form fixed dunes in Maqu alpine degraded grasslands of northwestern China.However,due to strong dormant characteristics of C.brunnescens seeds,the sand-fixing effect of the plant is severely limited.This study explores a technique that can rapidly promote the seed germination of C.brunnescens,and also investigates the adaptation and sand-fixing effect by cultivating C.brunnescens seedlings to establish living sand barriers in the sand ridges of moving sand dunes.Results show that the seed germination rate obtained a maximum of 63.7%or 65.1%when seeds were treated with 150 mg/L gibberellic acid(GA3)for 24 h followed by soaking in sulfuric acid(98%H2SO4)for 2.5 min or sodium hydroxide(10%NaOH)for 3.5 h,and then germinated(25°C in daytime and 5°C at nighttime)in darkness for 10 d.After breaking seed dormancy of C.brunnescens,the living sand barrier of C.brunnescens(plant spacing 15−20 cm;sand barrier spacing 10−20 m)was established in the perpendicular direction to the main wind in the middle and lower parts of the sand ridges on both sides of the moving sand dunes.When the sand ridges were leveled by wind erosion,the living sand barrier(plant spacing 15−20 cm;sand barrier spacing 0.5−1.0 m)of C.brunnescens was reestablished on the wind-eroded flat ground.Finally,a stable sand-fixing surface can be formed after connecting the living sand barriers on both sides,thus achieving a good sand-fixing effect.These findings suggest that rapid seed germination technology combined with the sand−fixing method of C.brunnescens can shorten the seed germination period and make the seedling establishment become much easier which may be an effective strategy to restore and reconstruct Maqu degraded grasslands.
基金supported by the National Agricultural Sci-Tech Transformation Foundation of China (Grant No. 2009GB23600512)the National Natural Science Foundation of China (Grant No. 30770347)the National Scientific Research Special Funds of Public Service Sectors of Forestry of China (Grant No. 201004045)
文摘We studied pot cultivated Haloxylon ammodendron＇s growth, physiological changes and drought resistance under NaC1, H2SiO3, and NaCl＋H2SiO3 treatments. Results show that 0.3 g/kg NaC1, 0.2 g/kg HzSiO3 or 0.3 g/kg NaCI＋0.1 g/kg H2SiO3 treatments can effectively promote growth and improve the drought resistance of/-L, ammodendron. Compared with that without NaCI treatment, H. ammodendron＇s height, crown diameter and fresh weight increased by 42%, 91% and 62% respectively under 0.3 g/kg NaC1 treatment, and its main stem diameter, main root diameter and main root length increased by 40%, 39% and 23%, respectively. Compared with that without H2SiO3 treatments, H. ammodendron＇s height, crown diameter and flesh weight increased by 36%, 45% and 27% respectively under 0.2 g/kg HeSiO3 treatment, and its main stem diameter, main root diameter and main root length increased by 23%, 23% and 20%, respectively. Compared with that under 0.3 g/kg NaC1 treatment, H. ammodendron＇s height, crown diameter and fresh weight and main root length increased by 9%, 10%, 17% and 12% respectively under 0.3 g/kg NaCI＋0.1 g/kg H2SiO3 treatment. Compared with that under 0.1 g/kg H2SiO3 treatment, H. ammodendron＇s height, crown diame- ter and fresh weight increased by 28%, 76% and 68% respectively under 0.3 g/kg NaCI＋0.1 g/kg H2SiO3 treatment, and its main stem diameter, main root diameter and main root length increased by 30%, 32% and 27%, respectively. This suggests that moder- ate levels of NaCI＋H2SiO3 interaction can effectively promote growth and improve drought resistance of/-L, ammodendron than separate applications of NaC1 or H2SiO3.
