Abstract:GGB is a negative regulator of drought resistance. In order to obtain the Arabidopsis ggb mutant, we used AtU6 promoter to drive the expression of AtGGB sgRNA and coresponding CRISPR/Cas9 genome edting vector was constructed and was transferred into Arabidopsis by Agrobacteriummediated floral dip. After sequencing of GGB in T₂ generation, two kinds of mutants with a deletion of 4 bases and an addition of 1 base (T) were found at the target site, respectively. Semiquantitative RTPCR analysis results showed that the expression of GGB gene was almost not detected in the ggb mutant, which indicated that the mutants were GGB knockout lines. Through measuring the water loss rate, drought resistant and seed yield per plant, ggb mutant exhibited decreased water loss rate, improved drought resistance, but unchanged seed yield per plant compared to wildtype. Taken together, the above results indicated that GGB is an ideal candidate target gene for crop molecular breeding and ggb mutant is useful for functional complemention of GGB homologous genes cloned from crops.

Abstract:Auxin binding protein (ABP) plays an important role in auxin signal transduction and the regulation of plant growth and development. To study the function and expression features of the ABP gene in sugarcane, we cloned an ABP gene from a sugarcane cultivar (Badila) using RTPCR. Sequence analysis showed that it contained a 615 bp open reading frame (ORF) and encoded a deduced protein of 204 amino acids. It was designated as ScABP4 because of the multiple sequence alignment and phylogenetic tree analysis results revealed that it had closer relationships with ABP4 in Sorghum bicolor and Zea mays. It was cloned into the prokaryotic expression vector pGEX6P1 and expressed a 22.5 kD protein successfully in E. coli. Subcellular localization assay showed that ScABP4 protein is located in the reticular of cytoplasm and on the cytomembrane; protein structure prediction showed that it has a signalpeptide, speculate it may be stored in the endoplasmic reticulum, and exert its function on the plasma membrane. qRTPCR showed that ScABP4 expressed in bud, root, stem and leaf in sugarcane with the highest expression level in bud. ScABP4 was upregulated by IAA or dark treatments indicated that ScABP4 might participate in sugarcane responses to auxin, and involved in light signaling pathway(s). In addition, the expression of ScABP4 in sugarcane was induced by ABA, JA, SA and CuCl₂ but was downregulated by CdCl₂. These results indicated that ScABP4 might involve in the sugarcane resistance to disease, osmotic and heavy metal stress, which provides the basis for further studying the functions of ScABP4.

Abstract:To obtain bluish Lilium spp. in direct breeding, we screened the suitable varietyOT lily Robina for genetic transformation. Here, both embryonic callus induced from filament and regenerated bulb scales of OT lily Robina were used as the transformation material. Agrobacteriummediated transformation of Phalaenopsis F3′5′H was studied. The results showed：with the preculture 3 d, OD₆₀₀ =0.8, infection time 10 min, cocultured for 3 d, 100 μmol/L acetosyringone conditions, the stable transformation rate of regenerated bulb scales could reach to the highest 12.78%; however, embryogenic callus preculture 2 d, OD₆₀₀= 0.8, infection time 10 min, cocultured 3 d, with 100 μmol/L acetosyringone conditions, which the stable transformation rate was the highest 12.22%. In all the conditions, the best hygromycinresistant screening concentrations always was 20 mg/L. PCR and reverse transcription PCR assay showed 9 putative transgenic plants were obtained. Southern hybridization analysisfurther proved 6 plants that the transgenic lilium flowers carry blue gene F3′5′H. The results provided technical support and material basis for the continuing development of novel bluish Lilium flowers.

Abstract:A full length cDNA of a vacuolar H⁺PPase gene (named ThVP1) was isolated from the transcriptome cDNA librarys of Tamarix hispida. ThVP1 was 3 022 bp in length, including an open reading frame of 2 298 bp which was predicted to encode a polypeptide of 765 amino acids. The estimated molecular weight and isoelectric points of the putative protein were 80.37 kD and 5.25, respectively. Hydrophobicity analysis and transmembrane domain prediction indicated that the ThVP1 contained 13 potential transmembrane domains with strong hydrophobicity. The amino acids sequence of ThVP1 contains three conservative domains (CS1, CS2 and CS3)，which shows 93% identities in amino acids sequence to vacuolar H⁺PPase genes from Reaumuria trigyna. Phylogenetic analysis indicates that ThVP1 belongs to class I type vacuolar H⁺PPase gene. Quantitative realtime PCR assay revealed that the mRNA level of ThVP1 was significantly upregulated by more than 20 fold higher than that of control under NaCl and PEG treatments in Tamarix hispida, suggesting that ThVP1 might play an important role in salt and drought tolerance of T. hispida.

Abstract:Rehmannia glutinosa was used as experimental material in this study. Through analyzing the transcriptome data of R. glutinosa and designing specific primers, we isolated the cDNA sequence of geranylgeranyl pyrophosphate synthase (GGPPS) from R. glutinosa and named as RgGGPPS1 (GenBank accession No. KU258808). Meanwhile, on the basis of bioinformatic analysis, we performed the prokaryotic expression, purification and tissuespecific expression analysis. The results indicated that: (1) RgGGPPS1 has an open reading frame (ORF) of 987 bp, which encoded a protein of 328 amino acid residues. (2) Bioinformatic analysis indicated that RgGGPPS1 protein contains the two conserved motifs (DDXXXXDD) and (DDXXD); RgGGPPS1 protein showed the highest homology, 92% identity, with GGPPS protein from Sesamum indicum. (3) By utilizing the construction of prokaryotic expression vector pET32aRgGGPPS1, we successfully expressed the recombinant RgGGPPS1 protein in E. coli BL21 (DE3) cells. Furthermore, the recombinant RgGGPPS1 protein was purified through Ni²⁺ affinity chromatography. (4) Realtime PCR analysis indicated that RgGGPPS1 was expressed in high transcript level in roots, low levels in leaves and stems. The results of this study provided the fundamental information about RgGGPPS1 gene for followup research of its function involved in iridoid glycoside biosynthesis pathway.

Abstract:Geraniol synthase (GES), which is very important to the biosynthesis of geraniol, is one of the key enzymes in terpenoids pathways. Based on the transcriptome analysis of P.cablin, one unique sequence encoding GES was discovered and the primers for PCR were designed from it, the fulllength GES cDNA was cloned using RTPCR strategy and its bioinformatics analysis has been done. Gene expression profile of PcGES1 in leaves and stems of different development stages of four cultivars was evaluated using quantitative reversetranscription polymerase chain reaction (qRTPCR). The results showed that the gene GES in P.cablin, named as PcGES1, accession number KF926075 in GenBank, contains a 1 734bp open reading frame and encodes a predicted protein of 577 amino acids. Phylogenetic analysis indicated that the amino acids encoded by GES1 of P. cablin were closest to that of Ocimum basilicum. PcGES protein was located in chloroplast, no transmembrane district. qRTPCR analysis indicated that PcGES1 mainly expressed in leaves, and the highest expression was in old leaves. The expression pattern analysis of PcGES1 among four cultivars indicated that the expression pattern of P. cablin (Blanco) Benth. cv. shipaiensis was similar to P. cablin (Blanco) Benth. cv. gaoyaoensis, while that of P. cablin (Blanco) Benth. cv. hainangensis was similar to P. cablin (Blanco) Benth. This study provided a foundation for exploring the mechanism of terpenoid biosynthesis in P. cablin plants.

Abstract:In this study, βtubulin genes of Salix matsudana Koidz. and S. matsudana var. tortusoa （Vilm.）Rehd. were cloned and identified. The sequence similarity, phylogeny, chromosomal localization and expression patterns were further analyzed. The result showed that each willow contained 20 βtubulin genes, and each gene shared more than 74.0% and 86.6% nucleotide and amino acid sequence similarity with one another in each willow species. There was over 85.8% amino acid sequence similarity of the βtubulin between the two willows. While the amino acid sequence similarity among Salix and other plants were larger than 81.5%. In the phylogenetic analysis, βtubulin proteins formed four classes, and it was presumed that Salix βtubulin gene families had undergone salicoid duplication and tandem duplication events combined with the study of chromosomal location of poplar βtubulin. However, TUB11 and TUB12 were possibly derived from segmental duplication or replicative transposition. The expression pattern analysis showed a tissue specificity of βtubulin genes in willows, and a section of duplicatedgene pairs showed different expression patterns in tested tissues. High degree of sequence similarity, evolutionary expansion and of members and expression pattern diversity of Salix βtubulin gene families might confer flexibility in cell division and growth which is of important significance to the development and growth habit of perennial woody plants.

Abstract:A rice semidwarf and deformed flower mutant, temporarily named as sddf3, was identified from ⁶⁰Co γray radiation mutation in japonica rice variety Nipponbare. The mutant was characterized by semidwarf, more tillers, semienclosed panicle, stamens dysplasia and nonpollen. Genetics analysis indicated that the mutant was controlled by a single recessive gene. The F₂ mapping population was derived from a cross between the heterozygous sddf3 genotype and a wide compatible variety Dular. The gene was located in a 227 kb region between the In/Del marker 333591 and 333818 on chromosome 3 in rice, which was assumed to be a new gene controlling semidwarf and deformed flower.

Abstract:Sequencerelated amplified polymorphism technique was adopted to analyze 21 pomegranate accessions. Sixteen primer combinations with clear band patterns and polymorphism were selected from thirtysix primer combinations. 271 loci were detected by sixteen pairs of SRAP primers. Among them 194 were polymorphic, the polymorphic rate was 71.59％, an average of 16.94 loci and 12.13 polymorphic loci were amplified by each primer pair. The genetic similarity coefficient of 21 pomegranate accessions ranged from 0.63 to 0.89, with an average of 0.77. An unweighted pair group method with arithmetic mean (UPGMA) tree established from Jaccard similarity coefficients suggested that 21 pomegranate accessions were clustered into five subgroups. The average value of observed number of alleles, effective number of alleles, Neis gene diversity index, Shannons information index are 1.712 2, 1.352 8, 0.199 9 and 0.310 5, respectively. There was rich genetic diversity among the pomegranate accessions in Kashi Prefecture. The clustering results using SRAP markers were consistent with the phenotypic characteristics of pomegranate. Sequencerelated amplified polymorphism (SRAP) is a simple and effective method to research on genetic diversity of pomegranate.

Abstract:Standard plant root tip cytology research methods were used to study the chromosome number and karyotype of 5 populations of 3 Elsholtzia species. The result showed that:（1）the chromosome number of E. densa was 2n=16, and the chromosome number of E. flava was 2n=20, which were consistent with previous reports. Chromosome number of E. eriostachya was 2n=10, which is first reported here.（2） Cluster analysis results showed that E. flava has close relationship with E. densa. Only diploid and tetraploid were found in this genus and dominated by diploid.（3）Three conclusions were drawn by analysis of karyotype parameters: the karytypic formulae of E. densa Daocheng Wumingshan population 1 was 2n=2x=16=14m+2sm, and population 2 was 2n=2x=16=16m. CI of population 1 and population 2 were 39.57 and 42.32, AI were 2.75 and 2.87, respectively. The two populations have the same type of karyotype: 1A. The karytypic formulae of E. eriostachya was 2n=2x=10=10m, CI was 41.76, AI was 5.25 and the type of karyotype was 1B. The karytypic formulae of E. flava was 2n=2x=20=14m+6sm (Kunming population) or 2n=2x=20=16m+4sm (Nielamu population). CI of Kunming population and Nielamu population were 38.49 and 40.97, AI were 4.20 and 4.30, respectively. The karyotype types of Kunming population and Nielamu population were 1B and 2B.

Abstract:The characteristic changes of mucilaginous seed coat before and after wetting were observed by dissecting microscope and scanning electron microscopy. The effects of seed coat ornamentation and mucilage on water uptake，sand adhesion，floatability and germination of seeds were analyzed. The result showed that: (1) The seed coat ornamentation of Peganum multisectum was formed by outward protruding appendages on the outer periclinal walls of epidermal cells and presented a reticular structure. Pellicles covered on the polyhedral meshes of seed coat ornamentation, making the meshes form closed chambers. After absorbing water，the pellicles became mucilaginous and a lot of bubbles appeared in the mucilage chambers. The mucilage was gradually dissolved and disappeared after water absorptiondehydration. (2) The mucilage layer and chambers of seed can store much air，which facilitated seed floatation on moving water and further dispersal. Meanwhile，seed coat ornamentation and mucilage can enhance adhesive ability of seed to the soil and other plants，thereby escaping from seeds bareness to maintain seed vigor. The seed coat ornamentation and mucilage also can absorb a large amount of water quickly and hold water，thus maintaining soil seed bank in the harsh desert. (3) The mucilaginous seed coat can delay germination but promote seedlings growth in an unpredictable environment，which increasing the ability of plant establishment.

Abstract:We used scanning electron microscopy (SEM) in this experiment to observe the pollen and stigma morphology of Robinia neomexicana var. luxurians in different periods of development, and had taken photos for analysis. Besides, we pollinated the pollens of R. neomexicana var. luxurian to the stigmas of another R. neomexicana var. luxurian and highquality clone of R. pseudoacacia (R. pseudoacacia ‘Luci 152’), and we used aniline blue stain to observe the germination process of pollen tubes in vivo. And then, we analyzed the pollination compatibility of this species. The results show that: (1) The average size of the pollen is 32.08 μm×19.55 μm (poleaxis length × equatorial axes length). The shape of the pollen is long spheroidicity with three germinal furrow, a little square. At the flowering moment, the pollen grows to the maximum, its microscopy becomes full. This is the best time to collect the pollen of R. neomexicana var. luxurians. (2) The surface of the stigma has mucilage and bulges. It has much mucilage at 12 h before flowering and the receptivity is the best. At 48 h after flowering, the stigma begins to break, the receptivity is already very bad, and the whole receptive period of the stigma is about three days from 24 h before flowering to 24 h after flowering. (3) The pollen of R. neomexicana var. luxurian could germinate in both R. neomexicana var. luxurian and R. pseudoacacia ‘Luci 152’ treated as the female parent, but the former germinates later and elongates slower, which illustrates that the pollen of R. neomexicana var. luxurian has affinity with both the stigmas of R. neomexicana var. luxurian and R. pseudoacacia ‘Luci 152’, but the affinity with the former is worse.

Abstract:Micromorphological characters of leaf abaxial epidermis of 20 species, 6 subspecies and 2 varieties of Poa was examined by light microscope and scanning electron microscope, to infer its significance for classification of the genus Poa.The results indicated that: (1) the leaf abaxial epidermis of Poa were characterized by longtubular, fusiform or shorttubular longcells with straight or sinuous wall; presence or absence of shortcells in intercostal zone; frequent stomata and parallelsided or domeshaped subsidiary cells distributed in intercostal zone; presence or absence of pricklecells in costal zone, absence of pricklecells in intercostal zone; elliptic, reniform, crescentic, subsquare, horizontallyelongated sinuous or nodular silicacells distributed solitary or in pairs in costal zone; presence of crown cells in some species. (2) Variations of leaf epidermal features existed at the species level, such as shape and wall thickness of longcells, presence or absence of shortcells and its shape, distribution of stomata and shape of subsidiary cells, distribution of pricklecells, and shape of silicacells distributed in costal zone. The micromorphological study revealed that the characters of leaf abaxial epidermis could provide evidences for classification of the genus Poa. Moreover, the evidences of leaf abaxial epidermis confirmed the view that P. pratensis subsp. angustifolia and P. pratensis subsp. alpigena were the subspecies of P. pratensis subsp. pratensis.

Abstract:In order to elucidate absorption, distribution and tolerance mechanisms of Brassica chinensis L. to chromium (Cr⁶⁺) stress, we grew two Brassica cultivars; ‘Meijiahua’(Cr⁶⁺stress tolerant) and ‘Sanyueman’(Cr⁶⁺stress sensitive) hydroponically in Hoagland 0, 10, 50 and 100 μmol·L^-1 Cr⁶⁺. The differencesin Cr absorbed contents and subcellular distribution, nonproteinthiol, phytochelatins(PCs) and antioxidant enzyme activities in shoots and roots were studied. The results were as follows: (1) the contents of Cr in shoots were significantly lower than those in the roots in both cultivars. The Cr root contents, Cr retention rate and the ratio of wallbounded Cr to total Cr in shoots and roots of ‘Meijiahua’ were significantly higher than those in ‘Sanyueman’, but the ratio of water soluble Cr to total Cr was opposite. (2) Cr⁶⁺ treatments at all concentrations significantly increased the concentrations of nonprotein thiol and phytochelatins (PCs) in shoots of both cultivars, but the increment in ‘Meijiahua’ was significantly higher than that in ‘Sanyueman’. (3) Under low concentration of Cr⁶⁺ (10 μmol·L^-1)，the activities of SOD, POD and CAT were significantly increased, but the extent of increase was significantly higher in ‘Meijiahua’ than that in ‘Sanyueman’. The activities of SOD, POD and CAT were significantly downregulated under high concentration of Cr⁶⁺ (100 μmol·L^-1), but the magnitude of downregulation in ‘Meijiahua’ was significantly lower than that in ‘Sanyueman’. These results indicated that under Cr⁶⁺ stress, as compared to ‘Sanyueman’, more Cr was distributed in cell walls in shoot and root in ‘Meijiahua’ to inhibit the transmembrane Cr to intracellular flow. Moreover, it has higher antioxidant enzyme activities and PCs content, so it showed a stronger tolerance to Cr⁶⁺.

Abstract:The purpose of this study is to explore the role of mitochondrial alternative oxidase (AOX) in photoprotection in apple leaves under water stress. After treated with salicylhydroxamic acid (SHAM) to inhibit the AOX pathway, we studied the effects of AOX pathway on photoprotection in Malus hupehensis detached leaves under water stress by simultaneously analyzing chlorophyll a fluorescence transient and light absorbance at 820 nm. The results indicated that water stress induced the upregulation of AOX activity. The inhibition of AOX pathway caused more severe photoinhibition. Under water stress, maximum quantum yield of primary PSⅡ photochemistry (TRo/ABS) and PSⅡ trapped electron being transferred from Q_A to Q_B (ETo/TRo) decreased, average absorbed photon flux per PSⅡ reaction center (ABS/RC) increased, while the maximum PSⅠ redox acitity(ΔI/I_o) was not affected. After treated with SHAM to inhibit the AOX pathway, ABS/RC markedly increased, TRo/ABS, ETo/TRo as well as ΔI/I_o significantly decreased. It was indicated that under water stress the inhibition of AOX pathway caused more severe photoinhibition, especially to the PSⅠ. Generally, the results demonstrate that the AOX pathway played an important role in the photoprotection in M. hupehensis leaves under water stress, particularly in the photoprotection of PSⅠ.

Abstract:Taking leaves and flower buds of Juglans sigillata as materials, we observed female bud physiological differentiation stage by paraffin method and determined the contents of chlorophyll and essential minerals nutritions in leaves by method of spectrophotometry, kjeldahl, molybdenum antimony colorimetric and ASS. We also analyzed hormones content in leaves, female bud and male bud by HPLCMS to research the relationship between chlorophyll, mineral nutritions and hormone contents and flower bud differentiation of J. sigillata. The results showed that: (1) The contents of chlorophyll a and chlorophyll b increased before female flower bud physiological differentiation, and present peak at morphological differentiation stage. (2) From physiological differentiation to the morphological differentiation, Ca and Mg contents reduced, K content increased. In the process of flower bud differentiation, P content showed a trend of declining, Fe content increased then fell, Zn content showed ‘M’ type. (3) GA₄ content in leaves and female flower buds fell sharply at physiological differentiation stage and present peak at morphological differentiation stage. ABA and ZR contents showed bimodal curve ‘M’ type in the process of flower bud differentiation. ZR content in the leaves showed a trend of low content continuously, and has a peak at physiological differentiation stage of female flower bud. The content of IAA was low during early morphological differentiation of flower buds. So, it is the critical period of female flower bud that transformed from physiological differentiation to morphological differentiation between the end of April and the middle of May. High content of chlorophyll in leaves and low contents of IAA, GA₄ in female flowers bud were beneficial to female buds early develop. A large amount of P was consumed during flower bud differentiation. High content of K is close to the critical period of female flower buds differentiation and Ca, Mg, Zn contents closely associated with female flower buds morphological differentiation. At the same time, the high contents of ABA, ZR in female flower buds have significant effect to both physiological and morphological differentiation, and high content of GA₄ involved in formation of flower primordium.

Abstract:Camptotheca acuminata Decne. (Nyssaceae) is a major source of anticancer camptothecin (CPT). It is imperative to induce CPT accumulation in order to develop CPT production strategies to satisfy clinical uses of CPT. In this study, twoyearold C. acuminata were dealt 8 h each day with UVB radiation for 12 days, and oneyearold C. acuminata were respectively arranged to radiate 2 h，4 h，6 h and 8 h with UVB radiation each day for 12 days. The contents of chlorophyll, MDA and free proline (Fpro), the activity of SOD in leaf and CPT content in young leaves, young shoots and root were separately measured after UVB treatment. In order to reveal that camptothecin is the defense product of UVB stress, the effects of UVB radiation on the physiological indices and secondary metabolites were analyzed. The results showed that: (1) in twoyearold C. acuminata, chlorophyll content was significantly decreased, MDA, Fpro and CPT contents were significantly increased after 8 h UVB treatment daily. It indicated that 8 h UVB radiation caused great stress influences on twoyearold C. acuminata. (2) In oneyearold C. acuminata, with the time of UVB radiation increasing, chlorophyll content was gradually decreased; Fpro content was significantly increased; MDA content had no significantly difference between 2 h and 6 h UVB radiation, but significantly increased after 8 h radiation compared with the control; SOD activity decreased firstly, then increased, lastly decreased with the time of UVB radiation prolonging every day. It showed that 8 h UVB radiation also caused stress influences on oneyearold C. acuminata. (3) CPT contents in vegetative organs of oneyearold C. acuminata were gradually increased with the time of UVB radiation prolonging, and the contents were the highest after 8 h UVB radiation each day. Moreover, CPT content increased more obviously in young leaves and young shoots than those in roots. It confirmed that enhanced UVB radiation caused certain damage to C. acuminata, and C. acuminata responded to this stress by not only changing physiological indices, but also changing secondary metabolism to accumulate CPT.

Abstract:In order to provide theoretical basis for improvement of apple production under rainshelter cultivation, we evaluated the effect of 5aminolevulinic acid (ALA) on low light tolerance of apple trees in this study. Specifically, the effects of 10 mg·L^-1 ALA on reactive oxygen metabolism and fast chlorophyll fluorescence characteristics of apple trees under low light conditions were investigated by root ALA application. Two apple cultivars, ‘Runtai 2’ and ‘Zhengyou 3’, were used, and three light conditions including normal natural condition (Control), light shading stress (LS), and severe shading stress (SS), were designed in our experiment. The main results were as follows: (1) Compared to the control, shading stress significantly decreased superoxide dismutase (SOD) and peroxidase (POD) activities, and increased the production rates of super anion (O^-·₂) and hydrogen dioxide (H₂O₂) and malondialdehyde (MDA) content in both apple cultivars. More increases in MDA content and the production rates of O^-·₂and H₂O₂ were found in ‘Zhengyou 3’. ALA significantly improved antioxidant enzyme activities, and reduced the production rates of O^-·₂and H₂O₂ and MDA content. The antioxidant capacity of ‘Zhengyou 3’ was improved more significantly by ALA than that in ‘Runtai 2’. (2) Chlorophyll contents and chlorophyll b/a ratio in apple trees increased under shading stress. ALA further promoted chlorophyll contents and chlorophyll b/a ratio in apple trees under shading stress. (3) Chlorophyll fluorescence parameter V_J, M_o, and DI_o/RC significantly increased, and ψ_o, ψE_o, ψR_o, PI_ABS, PI_CS, and PI_total dramatically decreased under shading stress. ALA inhibited changes of these chlorophyll fluorescence parameters under shading stress, even made them recover to the control levels. These results suggested that oxidative damage occurred in apple trees under low light conditions due to their low antioxidant capacities, and antioxidant capacity in ‘Zhengyou 3’ was lower than that in ‘Runtai 2’. ALA enhanced antioxidant capacity of apple trees, decreased low lightinduced oxidative damage, and improved ability of trapping and utilization of light energy, photosynthetic electron transfer ability, light use efficiency, and photosynthetic performance in apple trees under shading stress. Taken together, our results demonstrated that ALA improves low light tolerance of apple trees.

Abstract:Shoot apical bud cuttings of okra cultivar‘Qingfu’ in vitro (1.0 cm) were transplanted on MS basal medium supplemented with 0.05 g·L^-1 naphthalene acetic acid (NAA) and cultured under eight different quality lights: fluorescent lamp (CK), four mixture blue plus red light emitting diodes (BR_3∶1,BR_1∶1,BR_1∶3,BR_1∶4 LEDs), blue, red plus yellow (BRY=1∶3∶1) LEDs, blue, red plus green (BRG=1∶3∶1) LEDs, blue, red plus farred (BRFR=1∶3∶1) LEDs. The objective of present study was to determine the effects of different LEDs lights on the growth and physiological characteristics of okra (Abelmoschus esculentus) plantlets, and screen for optimal quality of okra plantlets in vitro in order to provide theoretical guidance and technical support of okra rapid propagation in vitro. The results showed that. (1) fresh mass, dry mass, root length, stem length and stem width were the greatest in plantlets cultured under BRY LEDs light; (2) root activity showed significantly higher in plantlets cultured under different lights than that of CK, and the highest was under BRY LEDs; Photosynthetic pigments were the highest in plantlets cultured under BRY LEDs, and which were also higher than that of other treatments; (3) the activities of SOD, POD and CAT were the greatest in plantlets cultured under BRY LEDs, and the lowest was that of CK; (4) the concentrations of soluble sugar, sucrose, soluble carbon and starch were the greatest in seedlings under BRY LEDs treatment, followed by BRG, and the lowest under CK; The concentrations of soluble protein, free amino acid and soluble nitrogen were the greatest in seedlings under BRY treatment, followed by BRG, and the lowest under CK. The present results indicated that larger and healthy plantlets and greater biomass of okra were produced in the presence of BRY (1∶3∶1) LEDs light. BRY light significantly promoted the root activity, photosythetic pigment content, antioxidant enzyme activities, carbon and nitrogen metabolism and accumulation of photosynthetic product of okra plantlets, which was the preferred light quality for the okra in vitro culture system.

Abstract:The annual Celtis sinensis and Ulmus pumila L. seedlings as test material to measure the growth, chlorophyll content, photosynthetic characteristics and chlorophyll fluorescence parameters of C. sinensis and U. pumila The desired salt concentration is made up 34.6‰ of the underground natural saline water, the soil reached 2‰,2.5‰,3.5‰ and 5‰ salinity separately. The growth (height and ground diameter) , varieties of chlorophyll content, photosynthetic characteristics and chlorophyll fluorescence parameters of C. sinensis and U. pumila were measured after 45 days to study their salt tolerance. The results showed that: (1) the growth of U. pumila was always higher than that of C. sinensis in all salt stress test. The C. sinensis chlorophyll content increased first，and then decreased, but, chlorophyll content of U. pumila less than control group and declined in every salt treatment. (2) Under different salt stress, initial fluorescence (F^o) , maximal fluorescence (F^m) and photochemical efficiency of PS Ⅱ (F^v/F^m) of C. sinensis and U. pumila are dropped. Compare these two species, these fluorescence parameters(F^o, F^m, F^v/F^m) of U. pumila slightly decrease, but,the nonphotochemical quenching coefficient (NPQ) of U. pumila increased significantly than that of C. sinensis when soil salt content more than 2.5‰. The chlorophyll content of C. sinensis is always higher than that of U. pumila under every salt stress, but the chlorophyll fluorescence is lower under higher salt stress condition(＞2.5‰); Under the condition of nonstress and lower salt stress, C. sinensis leaves possess better photochemical performance than that of U. pumila leaves. In conclusion, when soil salt content was higher (＞2.5‰). the changes of the photosynthetic and fluorescence parameters of U. pumila more stable than that of C. sinensis. Consequently, under salt stress environment, U. pumila can better adapt to salt stress environment than C. sinensis.

Abstract:Taking the fine roots of Cinnamomum septentrionale and Toona sinensis which were planted during early preliminary stage of lowefficiency Cupressus funebris forests transformation in the hilly region of central Sichuan as research objects, while using the unmodified pure C. funebris forest as control, we determined in situ respiration rates by applying a LI8100 soil carbon flux measurement system of the 1st-5th order roots and discussed the relationship among the morphological structure and the nutrient concentration of fine roots and respiration to reveal the structural and functional heterogeneity of fine roots. The results showed that the diameter of fine roots, root length and tissue carbon concentration of C. septentrionale, T. sinensis and C. funebris increased with the roots order increased, while specific root length (SRL), tissue nitrogen concentration and specific root respiration rate (SRR) reduced. And species, root order and their interactions showed that the morphology, nutrient concentrations and SRR of these three species fine roots were highly significant effect (P<0.01). Regression analysis indicated that three species SRR of these three species fine roots altered as diameter, SRL and tissue nitrogen concentration changed, which explained the variation with 64.7%, 87.6% and 67.6% of SRR, respectively. These results suggested that there was a close link among morphological characteristics of fine roots, the chemical contents and physiological functions, which provided an important basis to understand the structural and functional variation of plant roots.

Abstract:More than 2 600 moss specimens were collected from SinoVietnam border area (Yunnan & Guangxi, China) during 2012 to 2015. Through the specimen identification and literature research, we analyzed the species composition and floristic characteristics of SinoVietnam Border Area (Yunnan & Guangxi, China), comparisons of moss D_Gl and similarity index of genera & species along with floristic spectrum and the cluster analysis of SinoVietnam Border Area (Yunnan & Guangxi, China) with adjacent provinces and countries were made. Results are as follows: (1) the moss flora of SinoVietnam Border Area (Yunnan & Guangxi, China) consist of 452 species (including infraspecific taxa), belonging to 155 genera of 51 families. Taxithelium kerianum (Broth.) Broth. was reported new to China. (2) There are nine dominant families and 12 dominant genera in SinoVietnam Border Area (Yunnan & Guangxi, China). (3) The moss flora of SinoVietnam Border Area (Yunnan & Guangxi, China) is dominated by tropical Asia element, which accounts for 31.19% of the entire species. East Asia element (25.46%) and North Temperate element (13.76%) ranked second and third, respectively. (4)Vietnam has the highest similarity index of genera with SinoVietnam Border Area (Yunnan & Guangxi, China), whereas Guizhou(China) gets the highest similarity index of species within the studied area. (5) The moss flora of SinoVietnam Border Area (Yunnan & Guangxi, China) is more closely related to Guizhou, Guangdong, Fujian and Taiwan.

Abstract:ERECTA gene encodes a leucinerich repeat receptorlike Ser/Thr kinase. It participates in regulating morphogenesis of plant organs and plays an important role in the change of plant type and resistance to adversity. In the present study, pET21aCsERECTA, a prokaryotic expression vector with maltose binding protein tags was constructed and successfully expressed in E. coli BL21(DE3)．Expression conditions were optimized in the optimal temperature ,induction duration, and IPTG concentration．The fusion protein MBPCsERECTA was purified by nickel chelating chromatography and enzyme digestion was conducted by rTEV protease. The CsERECTA protein was obtained and it was used to prepare polyclonal antibody．The results showed that CsERECTA was expressed in the form of soluble and inclusion bodies in E. coli BL21(DE3), and a large number of proteins were soluble at low temperature. The optimal temperature,induction duration and IPTG concentration were 23 ℃,6 h and 0.5 mmol·L^-1, respectively．Western blot showed that the polyclonal antibody of CsERECTA has good specificity, because endogenous CsERECTA was detected. The successfully prepared polyclonal antibody can be used for further investigation, which establish the foundation for investigating the function of the CsERECTA gene in cucumber．

Abstract:Biophytum reinwardtii (Zucc.) Klotzsch, a newly recorded species of Oxalidaceae from China, is reported, and its lectotype is designated. An amplified description and related specimen photos are provided here. This species was newly found in Yingjiang County in the border area between southwest China and Myanmar. B. reinwardtii is similar to B. sensitivum, but differs from the latter by its pedicels 5-7 mm (vs. 1 mm) long in flowering.

Abstract:Iris latistyla Y. T. Zhao f. albiflora J. Luo, a new form of Iris (Iridaceae) in Xizang of China is described. It differs from the typical form, I. latistyla Y. T. Zhao, by having white petals, which is quite stable. The new form randomly occurs in populations of the typical form. For its potential medicinal research value, a short discussion is given.

Abstract:It was undertaken on the revision of Paeonia species in Qinling Mountains by the field investigation, herbarium specimens and literature record. The results showed that there were eight wild species and one cultivar in this region, and they were classified into two groups: sect. Mouton and sect. Paeonia. Geographic distribution study showed that four species belonging to sect. Paeonia: P. obovata, P. mairei, P. lactiflora, P. anomala subsp. veitchii, also P. suffruticosa Andrews and P. rockii were widespread, P. qiui and P. ostii were found in middle and eastern regions, and P. jishanensis was only in eastern region of Qinling Mountains. Finally, a key to species was proposed.

Abstract:The shoot apical meristem (SAM), which is the tissue located at the top of a plant, can continually undergo differentiation. The SAM gives rise to all aboveground organs, such as the stems, leaves, and flowers, through cell division and differentiation. SAM development is controlled by the external environment, endogenous hormones, and molecular regulation, accordingly with phased characteristics of the SAM. Here, we summarize recent advances in our understanding of the morphological structure of the SAM and how it is affected by environmental factors, hormones, and molecular regulatory networks. We also present the research status on SAM, including unsolved problems and future research directions.

Abstract:In the process of plantpathogens interaction, a series of signal transduction and defense system are excited in plant, which triggers rapid and effective defense responses. After activation of defense responses, will cause synthesizing and accumulating of a series of exogenous signaling molecules. The plant hormones salicylic acid (SA), jasmonic acid (JA) and ethylene (ET) are recognized as key players in the regulation of the signaling pathways involved. In this review, the recent research advances on the interaction among the three different signaling pathways are summarized. It also presented the function of several key regulatory proteins such as NPR1，EDS1，MPK4, which are known to play important role in SA and JA/ET signaling cross talk and coordinating their complex relationships. In addition, the prospect of future work is discussed in the review.