Growth-promoting bacteria(GPB)have shown promising effects on serving plants against environmental constraints such as drought.Nevertheless,simultaneous effects of different GPB have less been considered for arid land...Growth-promoting bacteria(GPB)have shown promising effects on serving plants against environmental constraints such as drought.Nevertheless,simultaneous effects of different GPB have less been considered for arid land plants and under field conditions.We investigated the effects of single and combined application of GPB,including free-living nitrogen-fixing bacteria(NFB),phosphate solubilizing bacteria(PSB),potassium solubilizing bacteria(KSB),a combination of NFB,PSB,and KSB(NPK),and control,at three drought stress treatments.In order to better understand the interactions between drought and GPB,we measured the morphological,biochemical,and physiological plant traits.The target plant was salt tree(Halimodendron Halodendron(Pall.)Voss),a legume shrub native to arid lands of Central and West Asia.All biofertilizer treatments enhanced the growth,physiology,and biochemistry of salt tree seedlings,and there were significant differences among the treatments.KSB and PSB treatments increased photosynthetic pigments,but KSB treatment was more efficient in transpiration rate and stomatal regulation and increased the soluble carbohydrates.PSB treatment had the highest effect on root traits,such as taproot length,root volume,cumulative root length,and the ratio of root to shoot.NFB treatment enhanced root diameter and induced biomass translocation between root systems.However,only the application of mixed biofertilizer(i.e.,NPK treatment)was the most significant treatment to improve all plant morphological and physiological characteristics of salt tree under drought stress.Therefore,our results provided improvement of some specific plant traits simultaneous with application of three biofertilizers to increase growth and establishment of salt tree seedlings in the degraded arid lands.展开更多
The genetic diversity of Artemisia halodendron(Asteraceae), a constructive and dominant species in Horqin Sandy Land,was investigated to examine the genetic relationships with different hydrothermal regions in Horqin ...The genetic diversity of Artemisia halodendron(Asteraceae), a constructive and dominant species in Horqin Sandy Land,was investigated to examine the genetic relationships with different hydrothermal regions in Horqin Sandy Land. We sequenced chloroplast DNA(cp DNA) fragments(trn L–F) of 243 plants from 10 populations across the Horqin Sandy Land.The analyses of cp DNA variation identified seven haplotypes. A low level of haplotype diversity(H_d=0.706) and nucleotide diversity(π=0.0013) was detected. Haplotypes clustered into two tentative clades. Low genetic differentiation among regions was consistently indicated by hierarchical analyses of molecular variance(AMOVA). Across the sampled populations, the haplotype distributions were differentiated with hydrothermal gradients.展开更多
The aim of the present study is to investigate the difference between ITS sequences ofArtemisia halodendron Turcz. from differ- ent habitat gradients in Horqin Sandy Land, with Artemisia depauperata Krasch. selected a...The aim of the present study is to investigate the difference between ITS sequences ofArtemisia halodendron Turcz. from differ- ent habitat gradients in Horqin Sandy Land, with Artemisia depauperata Krasch. selected as the outgroup. Results indicate that the total length ofA. halodendron ITS is 696 bp, the lengths of unaligned ITS-1 and ITS-2 sequences varied from 253 to 256 bp and 264 to 269 bp, respectively, and GC content of ITS-1 and ITS-2 sequences ranged from 54.02% to 54.77% and 56.75% to 58.64%, respectively. This indicates a high difference of length and composition of sequences in ITS-1 than ITS-2. The genetic identity between ITS sequences ofA. halodendron from nine populations ranged from 85.7% to 99.7% which indicates some genetic dif- ferentiation between sequences. In the maximum parsimony （MP） tree, most ITS sequences from A. halodendron show two major clades： Clade I and Clade II, with Clade II older than Clade I. The order is subp4→ subpl → subp2 → subp3→ subp8 → subp6 → subp7 → subp9 → subp5, and corresponding habitat order is： inter-dune lowlands → semi-mobile dune → mobile dune →semi-fixed dune -→fixed dune. This indicates a close relation between the evolutionary processes ofA. halodendron and deserti- fication forming processes and ecological restoration processes of Horqin Sandy Land.展开更多
基金supported by the Ferdowsi University of Mashhad,Iran(46099).
文摘Growth-promoting bacteria(GPB)have shown promising effects on serving plants against environmental constraints such as drought.Nevertheless,simultaneous effects of different GPB have less been considered for arid land plants and under field conditions.We investigated the effects of single and combined application of GPB,including free-living nitrogen-fixing bacteria(NFB),phosphate solubilizing bacteria(PSB),potassium solubilizing bacteria(KSB),a combination of NFB,PSB,and KSB(NPK),and control,at three drought stress treatments.In order to better understand the interactions between drought and GPB,we measured the morphological,biochemical,and physiological plant traits.The target plant was salt tree(Halimodendron Halodendron(Pall.)Voss),a legume shrub native to arid lands of Central and West Asia.All biofertilizer treatments enhanced the growth,physiology,and biochemistry of salt tree seedlings,and there were significant differences among the treatments.KSB and PSB treatments increased photosynthetic pigments,but KSB treatment was more efficient in transpiration rate and stomatal regulation and increased the soluble carbohydrates.PSB treatment had the highest effect on root traits,such as taproot length,root volume,cumulative root length,and the ratio of root to shoot.NFB treatment enhanced root diameter and induced biomass translocation between root systems.However,only the application of mixed biofertilizer(i.e.,NPK treatment)was the most significant treatment to improve all plant morphological and physiological characteristics of salt tree under drought stress.Therefore,our results provided improvement of some specific plant traits simultaneous with application of three biofertilizers to increase growth and establishment of salt tree seedlings in the degraded arid lands.
基金supported by research projects 2016YFC0500907,2017FY100205,41201561,Y551821001,and 145RJYA269
文摘The genetic diversity of Artemisia halodendron(Asteraceae), a constructive and dominant species in Horqin Sandy Land,was investigated to examine the genetic relationships with different hydrothermal regions in Horqin Sandy Land. We sequenced chloroplast DNA(cp DNA) fragments(trn L–F) of 243 plants from 10 populations across the Horqin Sandy Land.The analyses of cp DNA variation identified seven haplotypes. A low level of haplotype diversity(H_d=0.706) and nucleotide diversity(π=0.0013) was detected. Haplotypes clustered into two tentative clades. Low genetic differentiation among regions was consistently indicated by hierarchical analyses of molecular variance(AMOVA). Across the sampled populations, the haplotype distributions were differentiated with hydrothermal gradients.
基金financially supported by research projects 41201561, 2011BAC07B02, Y351151001, 41071185 and 31170413
文摘The aim of the present study is to investigate the difference between ITS sequences ofArtemisia halodendron Turcz. from differ- ent habitat gradients in Horqin Sandy Land, with Artemisia depauperata Krasch. selected as the outgroup. Results indicate that the total length ofA. halodendron ITS is 696 bp, the lengths of unaligned ITS-1 and ITS-2 sequences varied from 253 to 256 bp and 264 to 269 bp, respectively, and GC content of ITS-1 and ITS-2 sequences ranged from 54.02% to 54.77% and 56.75% to 58.64%, respectively. This indicates a high difference of length and composition of sequences in ITS-1 than ITS-2. The genetic identity between ITS sequences ofA. halodendron from nine populations ranged from 85.7% to 99.7% which indicates some genetic dif- ferentiation between sequences. In the maximum parsimony （MP） tree, most ITS sequences from A. halodendron show two major clades： Clade I and Clade II, with Clade II older than Clade I. The order is subp4→ subpl → subp2 → subp3→ subp8 → subp6 → subp7 → subp9 → subp5, and corresponding habitat order is： inter-dune lowlands → semi-mobile dune → mobile dune →semi-fixed dune -→fixed dune. This indicates a close relation between the evolutionary processes ofA. halodendron and deserti- fication forming processes and ecological restoration processes of Horqin Sandy Land.
