Abstract:In this study, we used wild type of Arabidopsis thaliana as tested materials, and the CmSAMDC gene from melon was built into the pCAMBIA1304 binary vector, then the vector was transformed into A. thaliana by using Agrobacteriummediated method. The transgenic plants overexpressing CmSAMDC were obtained by screened on MS medium containing 50 mg/L hygromycin, and then the salt tolerance test was performed by T₃ transgenic seedlings. The results showed that: (1) the plant overexpression vector 35S∷CmSAMDC was successfully constructed and finally the T₃ transgenic A. thaliana plants were obtained after transformed by Agrobacterium and resistance screened by hygromycin. (2) The lateral roots of the transgenic T3 lines were stronger than that of wildtype under 100, 150 and 200 mmol/L NaCl treatment. Meanwhile, the transgenic T₃ lines grew up normally under 200 mmol/L NaCl treatment by irrigating roots, while the wild type plants were significantly inhibited under the same condition. In addition, the T₃ transgenic seedlings were still alive under 400 mmol/L NaCl treatment by irrigating roots 16 days later whereas the wildtype plants gradually died. Furthermore, the level of MDA was higher in wildtype plants than that of transgenic plants under the same salt stress. The results showed that overexpressing of CmSAMDC gene could obviously enhance the salt tolerance of transgenic A. thaliana.

Abstract:We cloned the homologous which was the predicted gene of Brassica napus transcription factor TCP7like, named BnTCP7. The nucleotide sequence similarity of BnTCP7 and Brassica napus TCP7like NC_027757 was 95.68%. The open reading frame was 648 bp, encoding 215 amino acids. The comparison of BnTCP7 with other 19 TCP7 or TCP7like amino acids in Brassicaceaes, homologous proteins were found of TCP7 in B. napus and Raphanus sativus. And the domains have strong similarity and conservatism, especially near the N end with a typical helixloophelix structure. It also showed that BnTCP7 is a hydrophilic unstable protein which belongs to classⅠof TCP family. The online prediction and comparative analysis of secondary and tertiary structures of BnTCP7 and Arabidopsis thaliana AtTCP7 (NC_003076) further revealed that BnTCP7 has the typical structure of TCP family. Phylogenetic analysis indicated that BnTCP7 protein was clustered with Brassica napus (rape) NC_027757 in the same branch, and had the closest relationship. The expression patterns of BnTCP7 gene expression in different organs at different stages were analyzed by the transcriptional data which was found that there was a certain difference in the expression level, and the expression in the vegetative organs was higher than that of the reproductive organs. In addition, the effects of abiotic stresses and hormone treatments on the expression of BnTCP7 gene on the seedling of B. napus were analyzed experimentally. It was found that the BnTCP7 gene not only responds to the abiotic stresses of cold, heat and wound, but also participates in the signals transduction of ABA and GA₃ hormones, which indicated that BnTCP7 might play an important role in maintaining normal growth and development and stresses of plants.

Abstract:The study is based on the transcriptome data of Saussurea involucrata, using Premier 5.0 designing a pair of specific primers SiICE2Up and SiICE2Down, Using S. involucrata cDNA as a template and the open reading frame (ORF) of the S. involucrata SiICE2 gene was cloned and analyzed with bioinformatics. Plant expression vector pCAMBIA230035SSiICE2Nos was constructed and then introduced into tomato (Lycopersicon esculentum) by using Agrobacteriummediated transformation. Identification of transgenic plants by PCR and RTPCR. The relative expression level of SiICE2 gene in transgenic tomato lines was analyzed by qRTPCR. The cold resistance analysis was performed after the transgenic and wildtype tomatoes were treated at 0 ℃. The results show: (1) cloning of the S. involucrata SiICE2 gene and the opening reading frame (OFR) of the SiICE2 gene is 462 bp which encoded a deduced protein including 153 acids residues. Phylogenetic analysis revealed that the SiICE2 gene is closely related to Cynara scolymus L. (2) Plant expression vector pCAMBIA230035SSiICE2Nos was constructed and then introduced into tomato by using Agrobacteriummediated transformation. There are 9 strains of tomato plants of transgenic SiICE2 gene detected by PCR. (3) Membrane physiological index showed that the relative electrical conductivity and MDA content of the transgenic tomato were significantly lower than that of the wild type with the increase of the low temperature treatment time. The relative conductivity ratio of the transgenic tomato was 31.7% lower and the malondialdehyde content was 4.2 μmol/g lower than that of wild type at the treatment time of 24 hours. (4) Antioxidant enzyme activity assay showed that the POD, CAT and SOD activities of the transgenic tomato plants continuously increasing with the increase of the low temperature treatment time. The activities of transgenic POD, CAT and SOD were significantly higher than those of the wild type at each treatment time, and the wild type showed a trend of gradually increasing and then decreasing. The study found that the S. involucrata SiICE2 gene can significantly enhance the cold resistance of noncold domesticated tomatoes.

Abstract:Two auxin response genes named FvARF10 and FvARF18 were cloned from Fragaria vesca using RTPCR. Bioinformatics analysis showed that FvARF10 and FvARF18 contained 2 056 bp and 2 100 bp ORFs, encoding 685 and 699 amino acid residues, respectively. It is predicted that the molecular mass of FvARF10 and FvARF18 proteins were 75.73 kD and 76.78 kD, which isoelectric point were 8.12 and 6.55. Phylogenetic tree analysis indicated that FvARF18 was most closely related to MnARF18 from Morus notabilis, and FvARF10 was most closely related to BnARF10 gene from Boehmeria nivea. FvARF10 and FvARF18 are predicated to be auxin response genes that are located in the nucleus or cytoplasm. Promoter analysis revealed that the sequence of FvARF10 and FvARF18 contained multiple hormone response elements. Results of the realtime PCR analysis showed that FvARF10 and FvARF18 were constitutively expressed in all examined tissues. FvARF18 was strongly expressed in stem, while FvARF10 was strongly expressed in half red fruit. The relative transcript level of FvARF10 and FvARF18 were induced strongly under IAA treatment, and reached the maximum after treated by IAA 1 h. These results indicated that FvARF10 and FvARF18 genes may be involved in the regulation of vegetative reproduction and development of strawberry, which related to the signal transduction of auxin.

Abstract:To solve the problem of high cost for traditional method of hybrid seed production which involves hand emasculation followed by pollination, a largescale cotton tissue culture was carried out to creat a cotton mutant and developed a highly sensitive genetic male sterility since 2006. In 2012, a photoperiod sensitive genetic male sterility was screened out in their offspring which named PSM4 (Photoperiod sensitive genetic male sterility mutant of cotton). During 2012-2017, breeding,material selection, the growth and development investigation and characteristics of photoperiod were carry out in the experimental field of CRI (Cotton Research Institution of China) in Anyang, Henan Province and South Crop Breeding Base in Zhongliao Village, Jiyang Town, Sanya, Hainan Province. （1） PSM4 shows male sterility when the sunshine duration is more than 12 h; when between 11.5-12 h, it is in the fertility transformation stage; when less than 11.5 h, it shows normal fertility. （2） Shading experiments show that the crucialtime of anther and pollen abortion at 12-15 days before anthesis.（3） Paraffin section of anther shows the reason of pollen abortion is the lost of extine under long daylight exposure. （4） All individuals were fertile in F₁ population from the reciprocal crosses between PSM4 and six upland lines and the results shows that the photoperiod sensitive genetic male sterility character is controlled by their nuclear genes. Genetic studies indicate that PSM4 fertility was controlled by single recessive genes for the segregation of fertile and sterile plants ratio of 3∶1 in F₂ population and unaffected by the rainy weather. The successful cultivation of PSM4 will greatly advance the study of hybrid seed production and use in an industry revolution in cotton breeding.

Abstract:A rice shortroot mutant Osksr6 was identified from an ethylmethane sulfonate (EMS)mutagenized rice library. Phenotypic observation, genetic analysis and gene mapping analysis of Osksr6 were carried out. Results showed that: (1) at the 7 d old stage, there was no significant difference in plant height and the number of adventitious roots between the wild type and Osksr6, while the length of primary and adventitious roots of Osksr6 was decreased by 61.98% and 46.42% compared with the wild type, respectively. Furthermore, the development of lateral roots and root hairs in Osksr6 was also inhibited to varying degrees. At the maturation stage, the tiller number of Osksr6 significantly decreased, and the panicle length and seed rate of Osksr6 were also reduced. (2) Genetic analysis showed that the mutant phenotype was controlled by a single pair of recessive nuclear gene. (3) Mapbased cloning analysis located OsKSR6 to a 460 kb region between newly designed InDel markers 28420k and 28880k on chromosome 3. There is no gene reported to be involved in root development in this region. This result will be helpful for the cloning of OsKSR6 and further characterization of molecular genetic mechanisms underlying root architecture in rice.

Abstract:In order to investigate the sequence characteristics and expression of VOZ (vascular plant onezinc finger protein) transcription factors in pineapple, we analyzed the sequences of VOZ transcription factors by bioinformatics software. qRTPCR was performed to analyze the expression patterns of VOZ transcription factors in pineapple seedlings under the treatments of NaCl, drought, low temperature (4 ℃), mannitol, Eth, SA, ABA, H₂O₂ and PEG6000. The results showed that: (1) the VOZ transcription factors in pineapple, Arabidopsis thaliana and rice all contained two conserved regions, and protein analysis showed that the AcoVOZ was hydrophilic acid protein. Secondary structure prediction showed that the main structural elements of AcoVOZ protein were alphahelix and random coil. (2) qRTPCR analysis showed that the expression of AcoVOZ1 and AcoVOZ2 were significantly different from the control under different abiotic stress conditions. Among them, the expression levels of AcoVOZ1 and AcoVOZ2 showed a significant decrease under the treatments of NaCl, drought, low temperature (4 ℃), mannitol, ABA, and Eth. The results suggested that VOZ transcription factors in pineapple participate in the response process of pineapple under various abiotic stresses such as highsalt, drought and low temperature (4 ℃), which may be helpful for the further study on molecular mechanisms of pineapple stress resistance and genetic improvement of pineapple resistance.

Abstract:A population of 262 recombinant inbred lines (RILs) from a fluecured tobacco cross between Y3 and K326 by single seed descent (SSD) method was used to construct a genetic linkage map. 626 SSR loci were evenly mapped into 24 linkage groups (LGs) which spanned a total length of 1 120.45 cM. With a randomized complete block design, one location field tests with three replicates in two years were conducted to characterize seven agronomic traits related to leaf yield, including plant height (PH), internode length (IL), leaf number (LN), stem girth (SG), angle between leaf and stem (ALS), length of waist leaf (LWL) and width of waist leaf (WWL). Based on the data of field trials and rMQM method, we mapped and analyzed the QTLs for seven target characters. The results showed:（1）the seven target traits of fluecured tobacco had a wide range of continuous variation in the RILs population, with significant bidirectional superparental segregation, and the average value of each trait was very close to the midparent value. The average broad heritability of 7 agronomic traits was 73.33%, of which the generalized heritability of PH and IL was above 80%, while the SG and ALS was less than 60%, indicating that 7 agronomic traits related to fluecured tobacco yield were quantitative traits controlled by both microeffects and environmental conditions.（2）A total of 30 QTLs were detected on 9 linkage groups, while five major QTLs with relatively large effects, explaining for more than 10% of the phenotypic variation in the RILs population, related to PH, IL, LN, LWL, and WWL were detected by both two years. （3）The seven traits were largely correlated with each other. Consistent with this, some small regions harboring two or more closely linked QTLs of different traits were found in the genome. The results provide an important theoretical basis for developing high yield cultivars in tobacco through markerassisted selection (MAS).

Abstract:Transcriptome analyses of Saxifraga sinomontana and Saxifraga consanguinea were carried out by Illumina HiSeq^TM 2000, then the characteristics of SSR and SNP were generalized according to the sequences. The result indicated that: 4 622 SSR sites were identified among 63 763 Unigenes with the frequency of 7.25% in S. sinomontana, there were 110 repeat motifs and the density of SSRs was 1/10.00 kb; for S. consanguinea, 4 542 SSRs were distributed in 60 972 Unigenes which accounted for 7.45%, there were 85 kinds of repeat motifs and SSRs occurred every 10.40 kb in length, which was slightly lower than that of S. sinomontana. For the two species, the trinucleotide was dominant repeat motif. The repeat numbers of SSRs were mainly from 5 to 10 and their motif length mainly ranged from 12-30 bp, which suggested that these SSRs displayed high levels of polymorphism. Besides, there were 118 424 and 112 006 SNPs in S. sinomontana and S. consanguinea. The proportion of SNPs in the coding region were 30.40% and 28.59% respectively, and the proportion of the synonymous mutations in the coding region (30.27%, 28.48%) was significantly higher than that of the nonsynonymous mutations (0.13%, 0.11%). It was found that the relevant indicators of the two species showed no significant difference, which was probably related to the tissue and its development stage, as well as the phylogenetic relationships of the species.

Abstract:In this study, we investigated the fingerprint and genetic diversity of Sichuan elite Juglans regia cultivars to improve the identification ability for cultivars. The SSR markers were applied for genetic diversity and cluster analysis of 29 elite J. regia cultivars. The results showed that：（1） 121 genotypes and 80 alleles were identified by the 11 SSR markers, and per primer pair has 7.273 alleles and 11 genotypes. （2） Mean effective allele number (N_e), heterozygosity (H_o), expected heterozygosity (H_e), shannons index (I) and polymorphic information contents (PIC) of the 11 SSR markers were 3.644, 0.645, 0.718, 1.518 and 0.680, respectively. （3） The fingerprint of 29 J. regia cultivars were constructed by primer combination method using primers wga001, wga032 and zmz02. （4） Cluster analysis showed that the 29 J. regia cultivars were classified according to the priority of variety type. There is no obvious correlation among cluster relationship and geographical origin of the local J. regia cultivars in Sichuan. The results suggested that the 11 SSR markers can be applied to analyze the genetic diversity of walnut varieties in Sichuan (PIC>0.5); the genetic relationship of 29 Sichuan J. regia cultivars was relatively close, and theirs genetic basis are relatively narrow.

Abstract:In this study, we used the concentrations of 0.1%, 0.2% and 0.3% colchicine solution to treat the shoot tip growth points for 4 times when diploid Purple Tsaitai grows to cotyledon stage, respectively. The autotetraploid Purple Tsaitai was identified and screened. Then the nutritional qualities between diploid and tetraploid Purple Tsaitai were compared. The results are as follows: (1) using 0.2% colchicine solution to drip four times had the best treatment effect on Purple Tsaitai, and the induction rate of tetraploid Purple Tsaitai was 6.62%. (2) Morphologically, the leaves, flower clusters, flower organs, siliques and seeds of the tetraploid plants are significantly different in the greatness compared with diploid plants; Anatomically, the stomata became larger, but the density of stomata in tetraploid plants decreased. In addition, pollen of tetraploid plants showed rectangular, trapezoidal and other irregular shapes. In cytology, the chromosomes numbers of tetraploid and diploid plants were 40 and 20; Flow cytometry identification results showed that the fluorescence intensity of diploid plants was 956 725.15, while the tetraploid plants was 209 238 5.03, which was about twice diploid. (3) In the nutritional quality of plants, compared with diploid plants in nutritional quality, the total content of free amino acids and total chlorophyll in tetraploid significantly increase by 228.58% and 110.02%, respectively. However, the total contents of nitrate nitrogen, soluble protein, vitamin C, soluble sugar and cellulose in the tetraploid Purple Tsaitai significantly reduced by 48.99%, 43.20%, 45.81%, 44.50% and 59.97%, respectively. (4) Compared with diploid, tetraploid plants showed increasing in plant weight, leaf thickness, leaf width and petiole width, decreasing in plant expansion. The study found that the optimum concentration of colchicine to induce tetraploid purple Tsaitai was 0.2%. At the same time, tetraploid purple Tsaitai showed obvious high yield, but its overall nutritional quality was not higher than that of diploid plants.

Abstract:To explore the difference between waxy and nonwaxy barley, we used two waxy barley and two nonwaxy barley cultivars as materials in this paper. The development of caryopsis in waxy and nonwaxy barley were investigated by stereomicroscopy observation, histochemical staining, resin semithin slicing and optical microscope observation. The results showed that：（1）the changes of fresh weight, dry weight and moisture content of waxy and nonwaxy barley were basically consistent, and the growth curve was as ‘S’.（2）The results of I₂/KI staining for the endosperm and pericarp of two kinds of barley were different. The endosperm of waxy barley was stained redbrown by I₂/KI and its pericarp was stained blueblack, but the endosperm and pericarp of waxy barley were both stained blueblack by I₂/KI, and both waxy and nonwaxy barley have high amylose content in the pericarp. （3） The occurrence of waxy barley endosperm amyloplast was earlier than that of nonwaxy barley, and the proportion of small amyloplast was higher than that of nonwaxy barley. Also, the endosperm starch filling degree of waxy barley was better than that of nonwaxy barley.（4） Compared with nonwaxy barley, waxy barley showed lower apparent amylase and total starch content but higher soluble sugar content. The results show that the caryopsis growth law of waxy barley is similar to that of nonwaxy barley, but the accumulation law of the starch is different.

Abstract:Aerenchyma is a collection of air chambers or cavities within the parenchyma of plants. It is essential for the air exportation in aquatic and wetland plants. In this experiment, submerged macrophyte Potamogeton perfoliatus was used as material to observe the longitudinal section and transverse section of the stem via paraffin sectioning technology, the aerenchyma development process of stems and leaves were analyzed in time and space. The results demonstrate that: (1) the structure of the stem includes epidermis, cortex and vascular cylinders. Welldeveloped aerenchyma exists between the endodermis and epidermis. Stem aerenchyma forms about 0.6 mm from the stem apex and matures at about 2.4 mm. (2) The leaf consists of epidermis, cortical parenchyma cells and vascular cylinders. Leaf aerenchyma forms in the second to third neonatal leaves near the stemapex and only forms in the main vein. (3) The stem and leaf aerenchyma development processes are similar, closely spaced clusters of cells initially, then small intercellular spaces appear with the division of the cortical cells, and the subsequent expansion process of the lacuna involves the cell growth and division and cell degradation, ultimately, developed aerenchymaformed. (4) The aerenchyma development process was divided into four phases: solid phase, formation phase, expansion phase, and maturity phase. The development degree of stem aerenchyma varies widely in different phases, the porosity rates in the solid phase, the formation phase, the expansion phase, and the maturity phase are 0.54%, 10.90%, 27.61%, and 57.58%, respectively. However, the node aerenchyma is not welldeveloped and the porosity is only 3.62% at maturity.

Abstract:In this experiment, three different species of black currant ‘Adelinia’, ‘Brodtrop’ and ‘Heifeng’ were used as materials to study the growth of black currants leaves. The ascorbic acid (AsA) content, synthesis and metabolismrelated enzyme activities, and their relationship with each other in leaves of eight different development stages (leaf to senescence) of black currants were studied. The relationship between AsA content and enzymes related to metabolic synthesis during the process of leaf growth and natural aging was clarified, which laid the foundation for finding the best leaf picking stage, regulation of AsA content, and delaying the process of leaf senescence. The results showed: (1) AsA content and AsArelated metabolite levels in different varieties of black currant leaves have obvious diversity. During the leaf growth and development, the changes of total ascorbic acid (TAsA) and AsA contents in leaves were consistent among the three cultivars, and all of them reached the highest level in the mature leaves, and the AsA content in leaves of ‘Adelinia’ was the highest (98.33 μmol/g) at maturity, then declined rapidly with leaf senescence, and decreased to 34.57 μmol/g in the late senescence. (2) In the process of leaf growth and development, the change of Lgalactose1, 4lactone dehydrogenase (GalLDH) activity in the Lgalactose pathway was consistent with the change trend of AsA content. In the regenerative metabolism of AsAGSH, the activities of dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR) and glutathione reductase (GR) are the highest in the leaf spreading stage, and then follow leaf senescence to the lowest. This is similar to the change trend of AsA content, but the change in the activity of ascorbate peroxidase (APX) is exactly the opposite. The content of H₂O₂ in leaves gradually increased with the senescence of the leaves and reached the highest level during the aging period. (3) GalLDH showed highly significant positive correlation with TAsA, AsA, oxidized ascorbic acid (DHA), DHAR, and MDHAR. The higher the GalLDH activity in the leaves, the higher the content of AsA in the leaves; DHAR is also significantly positively correlated with TAsA, AsA and DHA. Studies indicated that AsA content in black currant leaves reached its highest level in mature leaves, and there was a significant difference between the varieties; GalLDH, DHAR may be the key enzymes in AsA anabolism of black currant leaves, which can be enhanced by increasing GalLDH and AsAGSH. Circulatory systemrelated enzyme activities increase AsA content in black currant leaves, thereby delaying senescence.

Abstract:To disclose the tolerant range of hydroponic Populus russkii to excessive boron and reveal the relative physiological mechanism, the present research studied the growth and physiological responses of hydroponic P. russkii to short term boron stress (1, 5, and 10 mmol/L boric acid). The results showed that: (1) the plants grew better under 1 mmol/L boric acid treatment than CK (1/2 Hoagland solution, 0.05 mmol/L boric acid). The content of leaf photosynthetic pigments, net photosynthetic rate, the activities of SOD and APX, and the content of ascorbic acid increased significantly. (2) P. russkii suffered slight stress under 5 mmol/L boric acid treatment as leaf chlorosis was observed. Compared with CK, the content of Chlb and the activities of SOD and APX increased significantly, while the Chla/Chlb ratio decreased. (3) Serious symptom (growth inhibition of shoots and roots) arose when the plants were treated with 10 mmol/L boric acid, accompanying with decrease of F_v/F_m and Chla/Chlb ratio, and increase of MDA content. The activity of POD, the contents of ascorbic acid, free proline, and soluble sugars increased significantly. The present study showed that hydroponic P. russkii can scavenge ROS effectively by upregulating the activities of antioxidant enzymes and the contents of nonenzymatic antioxidants and osmoprotectants under shortterm stress, resulting in strong tolerance ensuring the plants to grow normally under 5 mmol/L boric acid.

Abstract:In order to investigate the effect of aluminum (Al) stress on the ascorbateglutathione(AsAGSH) cycle in leaves of Cunninghamia lanceolata, and elucidate the role of antioxidant enzymes and AsAGSH cycle in C. lanceolata under Al stress, we employed two C. lanceolata families differing in Al tolerance (Alsensitive YX5 and Altolerant YX26), and analyzed the effect of Al stress on malondialdehyde (MDA) content, antioxidant enzyme activities, and AsAGSH cycle in leaves of C. lanceolata. The results showed that：（1） The MDA content in leaves of C. lanceolata increased significantly under Al stress as compared with the control, and the increased rate of MDA content in the leaves of C. lanceolata was lesser in the YX26 than that in the YX5.（2）The enzyme activities of peroxidase (POD), ascorbate peroxidase (APX), monodehydro ascorbate reductase (MDAR) and the contents of ascorbic acid (AsA), dehydroascorbic acid (DHA), glutathione (GSH), and oxidized glutathione (GSSG) were increased to varying degrees under Al stress, and the increased rate of enzyme activities and nonenzyme antioxidants in the leaves of C. lanceolata were higher in the YX26 than that in the YX5 except for AsA content. （3）The enzyme activities of catalase (CAT) and dehydroascorbate reductase (DHAR) were greatly inhibited in the YX5 under Al stress, while the opposite was true for the YX26. Moreover, the DHAR activity in YX26 was significantly higher under Al stress as compared with the control. Additionally, the superoxide dismutase (SOD) was suppressed in leaves of different C. lanceolata families under Al stress, and the decreased rate of SOD in YX26 was lower than that in YX5. （4） The avoved results suggested that the Altolerant C. lanceolata family can enhance the scavenged capacity for reactive oxygen species by efficiency maintaining the enzyme activities and nonenzymes antioxidants in AsAGSH cycle, and which may be the physilogical basis of resistant families in adaptation to Al stress.

Abstract:Effect of phosphorus supply on growth, nutrient content and related physiology of Rosa roxburghii seedlings were studied, which was helpful to understand the characteristics of adaptation to low phosphorus stress of R. roxburghii Tratt. seedlings. We used R. roxbunghii seedlings of ‘Guinong 5’ as materials and used cultivating quartz sand and vermiculite mixed matrix as cultivating method. The effect of different phosphorus supply levels on growth, root morphological characteristics, the activity of acid phosphatase (APase)，nitrate reductase (NR) in roots and leaves and secreted acid phosphatase (SAPase) in roots, the species and content of small molecular organic acids in roots, and the content of nutrient elements in plants of R. roxburghii seedlings were studied. The results showed that: (1) The growth of R. roxbunghii seedlings was inhibited when the supplying level of phosphorus was lower or above 45 mg·L^-1 than，with a significantly reduced biomass, total root length, total root surface area, total root volume, average diameter, total root tip number of R. roxbunghii seedlings. The rootshoot ratio, the root hair density and length of R. roxbunghii seedlings reached the maximum at 5 mg·L^-1 phosphorus level, those 3 indexes was decreased with the increasing of phosphorus supply level. (2) The activity of APase in roots and leaves and SAPase in roots of R. roxbunghii seedlings decreased with the increase of phosphorus level. The contents of oxalic acid, tartaric acid, citric acid, malic acid, acetic acid and succinic acid in roots of R. roxbunghii seedlings decreased with the increase of phosphorus level. The activity NR in leaves and roots of R. roxbunghii seedlings reached the maximum at 45 mg·L^-1 phosphorus level, the activity of NR in leaves and roots decreased obviously when the phosphorus level was less than or greater than that. (3)The contents of P, Ca and Mg increased of R. roxbunghii seedlings with the increase of phosphorus level, the contents of Zn decreased with the increase of phosphorus level. The contents of N, P, K, Mn, Cu and B of R. roxbunghii seedlings reached the maximum at 45 mg·L^-1 phosphorus level, the content of these elements decreased obviously when the phosphorus level was less than or greater than that. The studied showed that too low or too high phosphorus supply had adverse effects on growth and nutrient absorption of R. roxburghii seedlings. The increased of root hair length and density, the enhanced activity of APase in leaves and roots and SAPase in roots, the increased contents of small molecular organic acids were the important adaptation strategies for the R. roxburghii seedlings.

Abstract:We conducted pot culture experiment to study the effect of different nitrogen forms［NH₄⁺N, NO₃^-N, CO(NH₂)₂］ and ratios on the changes in nitrate and nitrite contents, the contents of nutrients and medicinal ingredients of Perilla frutescens (L.) Britt seedlings. We studied the impact of different nitrogen forms and ratios on the P. frutescens which mainly includes dynamic changes of nitrate and nitrite contents, nutritional components, mineral elements and secondary metabolites, in order to provides a theoretical basis for the rational application of nitrogen fertilizer in P. frutescens cultivation and production. The results showed that: (1) the contents of nitrate and nitrite in P. frutescens leaves accumulates with the time proceeding. Before harvesting, nitrate content reaches the lowest point when NH₄⁺N /NO₃^-N was 100∶0, the content of nitrite reaches the lowest point when NH₄⁺N/NO₃^-N was 25∶75. (2) The contents of soluble sugar and starch achieved the highest level when NH₄⁺N/NO₃^-N was 0∶100, but the contents of free amino acid and Vc achieved the highest level under amidenitrogen treatment; The contents of P, K and Ca had their maximum values when NH₄⁺N/NO₃^-N was 50∶50, the contents of Zn, Fe and Mn had their maximum values when NH₄⁺N/NO₃^-N was 100∶0, and the content of Mg was peaked when NH₄⁺N/NO₃^-N was 0∶100. (3) The contents of total flavonoids, volatile oil and rosmarinic acid firstly increased and then declined constantly along with the increase of NH₄⁺N/NO₃^-N ratio, and these contents peaked when NH₄⁺N/NO₃^-N was 25∶75; The relative content of anthocyanin achieved the highest level under amidenitrogen treatment. In the cultivation and production of P. frutescens, when the NH₄⁺N/NO₃^-N ratio of 25∶75, we can get the best medicinal quality and nutritional quality, and control the content of nitrite.

Abstract:We studied Pinus elliottii, Casuarina equisetifolia, Eucalyptus urophylla × E. grandis, Acacia cunninghamia and A. aulacocarpa plantations in the coastal sandy land of Fuzhou City, measured their water use efficiency by stable carbon isotope method, and explored water use efficiency (WUE), nitrogen (N) and phosphorus (P) status of foliar as well as their relationships. The results showed that：（1）There were significant differences in foliar δ₁₃C between P. elliottii and E. urophylla × E. grandis, A. cunninghamia and E. urophylla × E. grandis (P<0.05). However, there was no significant difference in foliar δ¹³C among P. elliottii, C. equisetifolia, A. cunninghamia and A. aulacocarpa. The foliar δ¹⁵N of A. cunninghamia and A. aulacocarpa were significantly higher than those of P. elliottii, C. equisetifolia and E. urophylla × E. grandis.（2）WUE varied with different tree species in the order of P. elliottii>A. cunninghamia>C. equisetifolia>A. aulacocarpa>E. urophylla × E. grandis. The WUE of foliar of P. elliottii was significantly higher than that of E. urophylla × E. grandis 36.87%, but there was no significant difference in water use efficiency between P. elliottii and other species.（3）The foliar N concentration of each species in turn was A. cunninghamia>A. aulacocarpa>E. urophylla × E. grandis>C. equisetifolia>P. elliottii. There was a significant difference between A. cunninghamia and P. elliottii, A. aulacocarpa and P. elliottii. The foliar P concentration of each species in turn was E. urophylla × E. grandis>A. cunninghamia>A. aulacocarpa>P. elliottii>C. equisetifolia. There was a significant difference between E. urophylla × E. grandis and P. elliottii, E. urophylla × E. grandis and C. equisetifolia, E. urophylla × E. grandis and A. aulacocarpa. The foliar N/P of C. equisetifolia and A. aulacocarpa was significantly higher than that of E. urophylla × E. grandis. There was no significant difference in foliar N/P among the other tree species.（4）The foliar δ¹³C showed a significant seconddegree parabola correlation with the foliar N concentration. The foliar δ¹⁵N was extremely significantly positively correlated with the foliar N concentration（P< 0.01）. The study found that there was a significant difference among WUE, foliar N concentration, foliar P concentration, and N/P. In addition, WUE had significantly negative correlation with foliar N concentration and foliar P concentration. The foliar N and foliar P concentration would be key factors affecting WUE in coastal shelterbelt tree species in coastal sandy land.

Abstract:The study investigated the community of Begonia jinyunensis and its associated species in Jinyun Mountain National Nature Reserve. With the sample plot as onedimension resource states and with the importance values as the resource state descriptor of the niche, the niche characteristics of B. jinyunensis populations based on the formulae by Levins and Hurlbert for niche breadth and Piankas niche overlap were measured, which clarified the relationship between the use of resources and competition among the species of the community, providing a basis for the protection of B. jinyunensis. The results showed that: (1) the niche breadths of Levins and Hurlbert for B. jinyunensis in the community were the highest, 6.744 40 and 0.717 80 respectively,indicating that its ability of using environmental resources was strong and the ecological adaptation range was also large. (2) The niche breadths (Ba) over 0.3 for its associated species were Elatostema rupestre, Arachniodes rhomboidea and Polystichum tsussimense, 0.460 00, 0.417 04 and 0.301 60 respectively, indicating that the three major associated species of B. jinyunensis had stronger competitiveness in the community. (3) Among 20 species, the highest niche overlap with B. jinyunensis was E. rupestre, 0.671 4, showing they both had similar environmental requirements. When resources were insufficient, there may be fierce competition between them. And 12 species overlapped less than 0.5, occupying 60%. The niche overlaps of most species with B. jinyunensis were low, which showed the demand of resources varied and the similarity of environmental adaptability was low among species, indicating the interspecific competition in the community was not intense. According to the research, the niche breadth of B. jinyunensis was large, the habitat was suitable for its survival and the competition among species was not intense. The niche factor currently was not the main reason causing it to be endangered. The main reason for the small population of B. jinyunensis and the islandlike distribution may be its vandalized habitat.

Abstract:Distributed extensively in the artificial Caragana intermedia shrublands, soil crusts play key roles in the hydrological process of earth surface．Taking the biological soil crusts of artificial C. intermedia forests in desert steppe as the research object, this paper studies the form and influencing factors of the surface soil hydrological effects of biological soil crust from the seasonal scale through the analysis of the monitor of the hydrological and physical characteristics of the soil in dry season and rainy season with or without crust processing. Several key results are shown as follows．(1) The dynamics of soil water content in the surface soil of the artificial C. intermedia stands in distinct patterns in the dry season and the rainy season. The waterholding effect is mainly manifested in small rainfall among which the most typical one is in summer with strong soil evaporation, but the relative waterholding capacity of the crust is weakened or even lost when in rainy season. (2) Due to the seasonal conversion of biological crusts activity, the soil capacity, saturated moisture content and total porosity on the surface layer of C. intermedia plantation have changed different degrees on the seasonal scale. (3) Whether in the dry season or the rainy season, the existence of biological crusts will reduce soil moisture infiltration performance, regardless of whether there is crust coverage, the soil moisture infiltration rate in the rainy season is lower than that in the dry season.

Abstract:Here, we report a new record of Platanthera angustilabris Seidenf., an epiphytic species of Orchidaceae collected from Lafu Dahei Mountain (near Hemo Village), Mengma Township, Menglian County, Yunnan, China in 2017. Platanthera angustilabris was found on a tree in a midmontane moist evergreen broadleaved forest at an elevation of 2 145 m. P. angustilabris has been recorded in Myanmar, Thailand and Vietnam. The species is very similar to P. sikkimensis, but P. angustilabris Seidenf. has longer narrowlylanceolate leaves up to 15 cm long, whereas P. angustilabris has shorter lanceolate leaves(up to 7 cm long only). Voucher specimens are preserved in the Herbarium of the Kunming Institute of Botany (KUN), Chinese Academy of Sciences.

Abstract:Two species, Orthotrichum pamiricum and O. scanicum, are reported from Xingjiang in the study. Among them, O. pamiricum has obtuse apex of leaves, stomtata immersed, at below the middle part of urn, outer layer of eight pairs of teeth reflexed when dry; and inner peristome segments 16. On the other hand, the main characters of O. scanicum has crenulate leaf apex, stomata semiimmersed, calyptra with a few hyaline hairs, and both peristome teeth and peristome segments 16, with 8 fine furrows. The morphological characters, habitat and geographical distribution, and morphological comparison with related species of them are discussed. The illustrations of each species are provided. The distribution of the two new species in China of Orthotrichum further indicates the rich biodiversity of Xingjiang, China, as well as the close bryoflora relationships between Xingjiang and Central Asia.

Abstract:Microorganisms have established a beneficial relationship with the plants by secreting auxin and auxin precursors and alter plants root system architecture. Moreover, other metabolites are secreted by microorganisms can also change the plant auxin signaling pathway. Thus, auxin and auxin signaling pathways play an important role during the process of microbes modulate plant root development. This review summarizes the role of auxin during the process of microorganism regulate the development of plant root system from auxin synthesis, auxin signal and auxin polar transport, including microorganism increase the content of plant endogenous auxin, enhance the signal of auxin and regulate the expression level of PIN protein. Further, we concluded how microorganism regulated plant physiological and molecular level to adapt the changes of root system, which laid the foundation for further research in this field.