The aims of this study were to explore the interspecific differences of Populus euphratica Oliv.and Populus pruinosa Schrenk populations and the intraspecific differences of males and females within the same species i...The aims of this study were to explore the interspecific differences of Populus euphratica Oliv.and Populus pruinosa Schrenk populations and the intraspecific differences of males and females within the same species in flowering phenological traits,and the effects of temperatures on flowering phenological traits in different growth years(2001–2003 and 2013–2015).The results showed that P.euphratica population flowered earlier than P.pruinosa population.Moreover,flowering phenological period of population,number of days of flowering phenological period per population,number of days of flowering phenological period per plant and average number of days of flowering period per plant of P.euphratica population were less than those of P.pruinosa population.The differences between male and female within the same species indicated that the flowering periods of males P.euphratica and P.pruinosa populations were earlier than those of female plants.For both species,flowering phenological traits were significantly and negatively correlated with the average temperatures in previous ten days,previous one month and previous three months of flowering.Both species are sensitive to temperature changes and adjust to the changes by advancing the start of flowering and prolonging the duration of flowering.展开更多
Populus euphratica and Populuspruinosa, sister species in the Turanga Section （Salicaceae）, growing in semi-arid saline areas are known for their high salinity tolerance. In this study, by combining growth level wit...Populus euphratica and Populuspruinosa, sister species in the Turanga Section （Salicaceae）, growing in semi-arid saline areas are known for their high salinity tolerance. In this study, by combining growth level with Na＋ and K＋ contents, the expression level of vacuolar Na＋/H＋ antiporters was investigated for NaCl-induced changes in P. euphratica and t3. pru- inosa calli. Compared to R euphratica, P. pruinosa calli grew well in 200 mM NaC1 stress from 14. to 21 days. Increasing the stressed time caused an increase in Na＋ content concomitant with a decrease in K＋ content in P. euphratica calli, whereas, with the presence of 200 mM NaCI, K＋ content has a less increase in 14 and 21 days than in 7 days which was detected in R pruinosa calli. The transcript levels of six genes coding for NHX-type Na＋/H＋ antiporters suggest that vacuolar NHX1-NHX6 antiporters play important roles in responding to salt stress in R pruinosa. Our data suggest that there exists a higher salt tolerance for P. pruinosa than P. euphratica at the cellular level, Na＋ avoidance or accumulation is observed in cellular compartments, and that expression of NHX antiporters is linked to the accumulator phenotype.展开更多
The influence of NaCl and Na 2SO 4 on the germination rate and cotyledon outspread rate of Populus euphratica and P. pruinosa seeds from different seed sources was studied in this paper. The results showed that the se...The influence of NaCl and Na 2SO 4 on the germination rate and cotyledon outspread rate of Populus euphratica and P. pruinosa seeds from different seed sources was studied in this paper. The results showed that the seed relative germination rate and cotyledon outspread rate were negatively correlated with salt concentration significantly. The order of salt tolerance of P. euphratica seeds and P. pruinosa seeds from different seed sources was given respectively.In the same concentration,to the germination and cotyledon outspread rate of P. euphratica from different seed sources,NaCl was more influential than Na 2SO 4.In 0～0 4% concentration,to the relative seed germination rate and cotyledon outspread rate of P. pruinosa from different seed sources,NaCl was less influential than Na 2SO 4,and in 0 4%～1 5%, NaCl was more influential than Na 2SO 4 Compared with P. pruinosa, the salt tolerance of P. euphratica in seed germination period was better.展开更多
Six plots were investigated and field data were obtained with the contiguous grid quadrate method in a natural Populus euphratica forest in the upper reaches of the Tarim river.We developed a static life table and a s...Six plots were investigated and field data were obtained with the contiguous grid quadrate method in a natural Populus euphratica forest in the upper reaches of the Tarim river.We developed a static life table and a survival function of Populus pruinosa population based on the population life table and a theory of survival analysis.Survivorship curves,and the mortality rate were determined,and population dynamics were analyzed by using the spectral analysis.The results showed that:1)Survival numbers of P.pruinosa populations were decreased with the increasing of age,and the expecting life of individuals with DBH larger than 40 cm declined obviously.2)The Survivorship curve of the populations was Deevey Ⅲ.Four survival functions showed that the P.pruinosa population declined in young age and stabilized in old age.3)There were two peaks of mortality rate existed in the lifespan:respectively occarred at the first and 11th age class periods.Seedling shortage was the restricting factor of development.4) The spectral analysis of the populations showed that there was a marked periodic fluctuation in the process of natural regeneration.5)The higher mortality rate of P.pruinosa seedlings might be integrated by the interplay of biological characteristics of P.pruinosa and deteriorating habitat(groundwater level decreasing).展开更多
基金financially supported by the National Natural Sciences Foundation of China(30060007)the National Basic Research Program of China(2012CB723204)the National Programs for Science and Technology Development of China(2013BAC10B01)
文摘The aims of this study were to explore the interspecific differences of Populus euphratica Oliv.and Populus pruinosa Schrenk populations and the intraspecific differences of males and females within the same species in flowering phenological traits,and the effects of temperatures on flowering phenological traits in different growth years(2001–2003 and 2013–2015).The results showed that P.euphratica population flowered earlier than P.pruinosa population.Moreover,flowering phenological period of population,number of days of flowering phenological period per population,number of days of flowering phenological period per plant and average number of days of flowering period per plant of P.euphratica population were less than those of P.pruinosa population.The differences between male and female within the same species indicated that the flowering periods of males P.euphratica and P.pruinosa populations were earlier than those of female plants.For both species,flowering phenological traits were significantly and negatively correlated with the average temperatures in previous ten days,previous one month and previous three months of flowering.Both species are sensitive to temperature changes and adjust to the changes by advancing the start of flowering and prolonging the duration of flowering.
基金Financial support for this research was provided by the Program for New Century Excellent Talents in the Ministry of Education in China(NCET-09-0446),NSFC(31370396,30800865) and lzujbky-2012-k22 to YuXia Wu
文摘Populus euphratica and Populuspruinosa, sister species in the Turanga Section （Salicaceae）, growing in semi-arid saline areas are known for their high salinity tolerance. In this study, by combining growth level with Na＋ and K＋ contents, the expression level of vacuolar Na＋/H＋ antiporters was investigated for NaCl-induced changes in P. euphratica and t3. pru- inosa calli. Compared to R euphratica, P. pruinosa calli grew well in 200 mM NaC1 stress from 14. to 21 days. Increasing the stressed time caused an increase in Na＋ content concomitant with a decrease in K＋ content in P. euphratica calli, whereas, with the presence of 200 mM NaCI, K＋ content has a less increase in 14 and 21 days than in 7 days which was detected in R pruinosa calli. The transcript levels of six genes coding for NHX-type Na＋/H＋ antiporters suggest that vacuolar NHX1-NHX6 antiporters play important roles in responding to salt stress in R pruinosa. Our data suggest that there exists a higher salt tolerance for P. pruinosa than P. euphratica at the cellular level, Na＋ avoidance or accumulation is observed in cellular compartments, and that expression of NHX antiporters is linked to the accumulator phenotype.
文摘The influence of NaCl and Na 2SO 4 on the germination rate and cotyledon outspread rate of Populus euphratica and P. pruinosa seeds from different seed sources was studied in this paper. The results showed that the seed relative germination rate and cotyledon outspread rate were negatively correlated with salt concentration significantly. The order of salt tolerance of P. euphratica seeds and P. pruinosa seeds from different seed sources was given respectively.In the same concentration,to the germination and cotyledon outspread rate of P. euphratica from different seed sources,NaCl was more influential than Na 2SO 4.In 0～0 4% concentration,to the relative seed germination rate and cotyledon outspread rate of P. pruinosa from different seed sources,NaCl was less influential than Na 2SO 4,and in 0 4%～1 5%, NaCl was more influential than Na 2SO 4 Compared with P. pruinosa, the salt tolerance of P. euphratica in seed germination period was better.
文摘Six plots were investigated and field data were obtained with the contiguous grid quadrate method in a natural Populus euphratica forest in the upper reaches of the Tarim river.We developed a static life table and a survival function of Populus pruinosa population based on the population life table and a theory of survival analysis.Survivorship curves,and the mortality rate were determined,and population dynamics were analyzed by using the spectral analysis.The results showed that:1)Survival numbers of P.pruinosa populations were decreased with the increasing of age,and the expecting life of individuals with DBH larger than 40 cm declined obviously.2)The Survivorship curve of the populations was Deevey Ⅲ.Four survival functions showed that the P.pruinosa population declined in young age and stabilized in old age.3)There were two peaks of mortality rate existed in the lifespan:respectively occarred at the first and 11th age class periods.Seedling shortage was the restricting factor of development.4) The spectral analysis of the populations showed that there was a marked periodic fluctuation in the process of natural regeneration.5)The higher mortality rate of P.pruinosa seedlings might be integrated by the interplay of biological characteristics of P.pruinosa and deteriorating habitat(groundwater level decreasing).
