Abstract:Huanan elephant grass (Pennisetum purpureum cv.Huanan) is widely used as forage in South China.It is also a highly yielding energy crop for ethanol production.However,the lignin in lignocellulose inhibits the activity of bioconversion.In order to explore the lignin regulation network,we isolated 4-coumarate CoA ligase (4CL) from P.purpureum cv.Huanan.A 1 943 bp cDNA sequence of Pp4CL gene was cloned by homology-based RT-PCR.Pp4CL has an open reading frame of 1 662 bp and encodes a 553 amino acid protein with a predicted molecular mass of 59.57 kD and a isoelectric point of 5.2.Pp4CL protein is a hydrophobin protein,and belongs to AFD class I superfamily as it contains an AMP binding domain.In phylogenetic tree,Pp4CL was clustered with At4CL1 and Os4CL1.Two conserved motifs,SSGTGLPKGV and GEICIRG,were found in Pp4CL,indicating that it was a typical plant 4CL.The pGEX-4CL prokaryotic expression vector was constructed and GST-tagged Pp4CL fusion protein with the molecular mass of 88 kD was obtained.This result laid foundation for the western blot and enzymology analysis.The overexpression vector named pBA-4CL was constructed,and three positive transgenic tobacco lines were obtained by leaf disc method.In petiole,acetyl bromide lignin content was greater by approximately 10% in OX-9,16.2% in OX-7,94.6% in OX-4 compared with WT plants.And in base stem,the three transgenic plants had 0.9%,4.0% and 13.5% more acetyl bromide lignin content than CK plant,respectively.In conclusion,overexpression of Pp4CL in tobacco leaded to increasing of lignin content,thus,Pp4CL was related to lignin biosynthesis.This research provides scientific basis for lignin improvement in elephant grass and molecular breeding in forage grass.

Abstract:Small G protein Ropplays an important role as molecular switch during signal transduction in plant cells.A Rop coding gene LjRac1 in Lotus japonicus was cloned by RT-PCR.The gene sequence analysis was carried out by the bioinformation method firstly.Then the expression profile of LjRac1 was detected in different tissues by semi-quantitative RT-PCR and in inoculated roots on different stage of post-inoculation using real-time RT-PCR,respectively.Moreover,over-expression recombinant plasmid was constructed and hairy root transformation method was used to investigate the over-expression effect of LjRac1 mRNA on the early nodulation process.The study revealed that:(1)LjRac1 gene sequence analysis showed that the length of LjRac1 genewas 594 bp,which encoded a peptide with 197 amino acids.LjRac1 contained conserved domains of Rop GTP ase proteins.Homology analysis showed that the deduced amino acid sequence exhibited high similarity with Glycine max GmRac1 and Glycine soja GsRac1(94.42%).(2)LjRac1 was expressed in root,stem,leaf,nodule and flower of L.japonicus,and preferentially expressed in root and nodule.The expression level of LjRac1 was elevated in root 0.5 h after inoculation with Mesorhizobium loti,as compared with that in uninoculated control root.(3)The expression level of LjRac1 mRNA in over-expression transgenic plants was 14.3 times higher than that of the control plants,and the number of nodules in over-expression transgenic plants significantly increased compared with the control plants.The data showed that LjRac1 was the gene of enhancement expression by the induction of M.loti and over-expression LjRac1 could increase the number of nodules,which indicated that LjRac1 gene might be involved in the early stage of symbiosis nodulation and regulated nodule development in L.japonicus.

Abstract:A full-length cDNA encoding pyruvate kinase was cloned firstly by RT-PCR and RACE-PCR from Lonicera japonica Thunb.,designated LjPkc (GenBank accession number JQ621946.1).The length of coding sequence (CDS) is 1 533 bp,which codes for a protein with 510 amino acids.LjPkc displayed high sequence identity with previously cloned Pkc gene of Nicotiana sylvestris and was clustered close to Pkc family genes of dicotyledon plants.Subcellular localization analysis showed that LjPkc protein may play an important role in the chloroplasts or mitochondria.The LjPkc proteins mainly have alpha-helix and random coil by spatial structure analysis.qPCR analyses showed that LjPkc is widely expressed in stem,leaf and flower of L.japonica Thunb.,but the mRNA of LjPkc has the highest expression level in yellow flower.The research is not only to enrich the gene resource of Pkc gene family,but also lay a foundation to reveal the biology function of LjPkc in sugar metabolism.

Abstract:This research used strawberry ‘Benihoppe’(Fragaria ananassa ‘Benihoppe’) as test materials,an ABA receptor gene FaPYL9 was isolated from strawberry fruit,it contains an open reading frame of 555 bp nucleotides,encoding 184 amino acid sequence and contains an amino acid conserved region PYR_PYL_RCAR_like.FaPYL9 gene expression in seven periods of strawberry fruit development showed that with strawberry fruit development FaPYL9 gene expression rapidly increased,and had the highest expression in the fruit full red stage.FaPYL9 gene RNA interference in strawberry fruit can delay the strawberry fruit ripe for 3 to 5 days.Meanwhile FaPYL9 gene RNA interference to reduce expression of fruit color related genes FaCHS and FaUFGT,sucrose and anthocyanin contents in fruit decreased,ABA content and fruit hardness increased.Results showed that the FaPYL9 gene plays an important role in the strawberry fruit development,FaPYL9 gene can promote strawberry fruit ripening.

Abstract:To identify the function of β-galactosidase (β-Gal) gene during ripening and softening,we isolated a β-Gal gene,named FaTβgal,from strawberry fruit (Fragaria ananassa Duch.cv Toyonoka) by suppression subtraction hybridization (SSH) and RACE techniques.The full length cDNA sequence of the FaTβgal gene is 2 891 bp and the open reading frame (ORF) is 2 448 bp which encoded a deduced protein including 815 amino acid residues.The FaTβgal protein is a member of the β-Gal gene family of glycoside hydrolase family 35 members,including conservative base sequence “GGPIILSQIENEY” and a galactose binding lectin domain.Blastp analysis revealed 47.1% to 48.1% similarities between FaTβgal and three reported F.ananassa genes of Faβgal1(CAC44500),Faβgal2(CAC44501) and Faβgal3(CAC44502).Phylogenetic analysis showed that FaTβgal was clustered on one independent branch with 24 β-Gal genes of other species.The relative expression of FaTβgal was determined by quantitative real-time PCR (qRT-PCR) during ripening and softening.The results showed that FaTβgal gene was expressed specifically at the mature stage of fruits,and the relative expression levels of FaTβgal genes increased rapidly with fruit ripening and reached a peak at the pink stage,then markedly declined at red fruit stage.The trends of β-Gal expression in two cultivars of Toyonoka and Sweet Charlie were similar during fruit development and ripening.These results indicated that the FaTβgal is a novel gene of the β-Gal gene family,and may play an important role in strawberry fruit ripening and softening.

Abstract:The brown plant hopper(BPH),Nilaparvata lugens,is one of the most destructive pests in rice production.Exploring resistance resources and developing resistance varieties of rice is a low cost and effective solution for protecting rice from BPH.Exploring BPH resistance genes from Yunnan wild rice materials could be used for developing new varieties of rice with high resistance.In this study,nine BPH resistance genes were detected in samples of Yunnan wild rice by phenotypic and PCR identification.The results showed that:Yunnan wild rice got different levels of resistance to BPH.Particularly,O.granulata and O.officinalis were highly resistant to the pest and could be used as excellent materials of insect resistance in breeding.According to PCR detection,the resistance genes Bph1 and Bph18(t) were not found in all three wild rice materials.O.rufipogon from Yuanjiang and Jinghong probably carry bph2.O.rufipogon from Dongxiang probably carry bph2,Bph15 and Bph27(t).O.granulata probably carry bph2 and bph19(t).O.officinalis and O.officinalis(broadleaf) probably carry bph2 and Bph6,respectively.O.officinalis F₁ probably carry bph2,Bph14 and bph20(t).O.officinalis F₂ probably carry bph2 and Bph27(t).These results provided a solid basis for exploring and using new BPH resistance genes from Yunnan wild rice.

Abstract:According to transcriptome data of Fagopyrum tataricum at flowering stage,we cloned a bHLH transcription factor gene and designated as FtbHLH4.The expression patterns of FtbHLH4 under abiotic stresses were determined by qPCR.The results showed that the DNA sequence of FtbHLH4 was 1 852 bp in length and contained 7 exons and 6 introns,and in line with the principle of GT-AG splicing principle.The cDNA of FtbHLH4 contains a 1 062 bp ORF,which encoded 353 amino acids residues,and a conserved Helix-Loop-Helix domain.The expression of FtbHLH4 was up-regulated under ABA,NaCl and PEG stresses.After being treated with ABA,NaCl or PEG for 48 h,the expression level of FtbHLH4 increased to the maximum,which was 11.3,12.0 and 6.1 folds of the control,respectively.However,the expression of FtbHLH4 was down-regulated under cold and UV-B stresses.The expression level decreased to 24% and 23% of the control after 6 h and 12 h stress treatments,respectively.These results suggested that FtbHLH4 participate in the response process of F.tataricum under the abiotic stresses in different mechanisms.

Abstract:In the present study,the phosphorus-deficiency tolerance introgression line IL171 and its parents (Oryza sativa cv.‘Xieqingzao B’ and Dongxiang wild rice) were used to investigate the differential expression genes at early seedling stage by cDNA-AFLP technique under the phosphorus-deficiency stress condition.Real-time fluorescent quantitative PCR was used to verify the differentially expressed genes.(1)cDNA-AFLP analysis revealed that numerous cDNA fragments (20-159) were obtained in each material under the phosphorus-deficiency condition compared to the control (normal phosphorus level).(2)Compared with ‘Xieqingzao B’,36 and 61 cDNA fragments were differentially up- and down-regulated in IL171,respectively.In Dongxiang wild rice line,79 and 136 cDNA fragments were differentially up- and down-regulated,respectively.Further analysis showed that IL171 and Dongxiang wild rice shared the same expression pattern at 13 up-regulated loci and 15 down-regulated loci.(3)Among the 60 recovered and sequenced TDFs (transcript-derived fragments),50 of them were obtained and their functions were determined through Blast search against the RAP-DB database.The functions of them were grouped into eight classes,including energy and metabolism,regulating genes,signal transduction and transcription factors et al.(4)Six above functional genes were subjected to real-time fluorescentquantitative PCR (qRT-PCR) analysis which was all in agreement with those of the cDNA-AFLP analysis,comfirming that cDNA-AFLP was reliable in detecting differentially expressed gens involved in responding to the phosphorus-deficiency stress.The results in this study suggested that partial alien DNA fragments of Dongxiang wild rice related to phosphorus-deficiency tolerance has been transferred into the introgression lines and they could be acted as excellent bridging germplasm in exploring and utilizing the phosphorus-deficiency tolerant genes in rice.In additon,the introgression linses derived from Dongxiang wild rice can be used a good experimental system for understanding the molecular mechanism to tolerate phosphorus-deficiency stress in wild rice.

Abstract:To well evaluate and utilize sugarcane germplasm,we analyzed the genetic diversity and fingerprint of 45 elite sugarcane germplasms,including 29 clones of germplasm innovation in Yunnan and 16 major parents,by simple sequence repeat (SSR) markers with 6 pairs of primers.The results showed that 6 primer pairs produced 104 bands,in which 101 were polymorphic,the percentage of polymorphic bands was 97.25%;the genetic similarity coefficient (GS) ranged from 0.235 3 to 0.891 3 with an average of 0.563 3 in 45 germplasms,and the genetic similarity coefficient ranged from 0.301 6 to 0.755 6 in 16 major parents of sugarcane,the number of specific bands in Yunnan germplasms of sugarcane innovation were 14-folds more than those in the major parents,containing Saccharum spontaneum,Saccharum robustum,Erianthus arundinaceum and Erianthus rockii.According to the similarity coefficient scope between 16 major parents of sugarcane,the 45 germplasms were clustered into 6 groups at 0.43,their genetic relationships were more far relatively,and suitable to be hybrid between the germplams.The rate of distinguishing cultivars by cluster UPGMA (RDVC%) was analyzed for each pair of primers,the value of polymorphism information content (PIC) ranged from 0.975 8 to 0.976 9,the standard fingerprint of Yunnan germplasms of sugarcane innovation was established by the primers of MSSCIR21 and SMC1047HA which had the highest efficiency primer combinations in identifying these sugarcane germplasms,and distinguish all the species in the similarity coefficient was 0.85,the identification accuracy is 100%,each germplasm has an unique fingerprint,and 16 major parents and 29 germplasm innovation can be distinguish,thus can be used in the hybridization,identification and intellectual property protection.

Abstract:The aim of this study was to investigate the fertility and its cytological mechanism in triploid grape ‘Summer Black’.The meiosis of pollen mother cells (PMCs) and gamete fertility in triploid grape 'Summer Black' were studied by cytogenetic methods.Results showed that:(1)numerous meiotic abnormalities,including precocious migration of chromosomes to the poles,lagging chromosomes,chromosome bridges,asymmetrical separation and micronuclei were found during the meiosis process.The frequency of asymmetrical separation (65.68%) was the highest in all of the meiotic abnormalities.(2)The pollen germination rate of this triploid grape was 1.65%,and its pollen sizes ranged from 18.0-50.0 μm with a bimodal frequency distribution.(3)Hybrid seedlings were obtained from crossing between ‘Summer Black’ and tetraploid varieties,which indicated some gametes were fertile in ‘Summer Black’.It was indicated that abnormal meiosis of PMCs was the cytogenetic reason for fertility reduction of triploid grape.While a little bit fertile unreduced pollens was produced by the abnormal meiosis.It was proved that the breeding application of this triploid grape was possible.

Abstract:Using the hand sliced method,we observed the external morphology and anatomical characters of fruit of 17 genera 23 species in Umbelliferae in this paper.There are three types of fruits:dosal strongly compressed,lateral strongly compressed and not compressed;Lateral ribs are wide or narrow;For vittae in the furrow,it contains mono-vittae and multi-vittae;The stylopodium of most species is conical,and that of a few species is flat;Calyx teeth are small or obsolete.The comparison of anatomical characters of fruit among different genera and within one genus shows that:(1)bristles or spines on the fruit surface and the features of ribs exhibit distinct differences among different genera,whereas are identical within one genus.The two characters can be evaluated as significant taxonomic references in the genus level in Umbelliferae;(2)the shape of fruit transection and the morphological characters of endosperm concrescence and calyx teeth are significant characters at the species level.Based on morphological characters of fruit,a key to 17 genera and 23 species is provided.

Abstract:The morphology of leaf abaxial epidermis of 21 species of Festuca was examined under light microscope and electron microscope.The results showed that:(1)the species of Festuca had Festucoid type epidermis.The leaf abaxial epidermis of Festuca were characterized by long-tubular or short-tubular long-cells with markedly sinuous walls or few straight walls,elliptic or crescentic or subsquare short-cells distributed solitary or in pairs,rare or one or more rows stomata,parallel-sided or dome-shaped subsidiary cells,frequent or infrequent prickle-cells,subsquare or elliptic or crescentic or horizontally-elongated sinuous costal silica-cells.There were abundant variations of epidermal features within the genus Festuca.(2)The morphology of leaf abaxial epidermis was conducted by UPGMA analysis.Two major branches formed in the UPGMA tree.The clade Ⅰ included the species with rare stomata and frequent prickle-cells,species of subgen.Festuca constituted the clade Ⅰ.The clade Ⅱ included the species with one or more rows stomata and infrequent prickle-cells.The second clade was comprised of Subgen.Schedonorus,Subgen.Subulatae,Subgen.Drymathele.

Abstract:To investigate the types and functions of dehydrin in tea plant [Camellia sinensis (L.) O.Kuntze],we studied the expression profiling of tea dehydrin protein family in different seasons and wintering period by Western-blot.The results showed that:(1)the phenol-methanol/ammonium acetate precipitation method was suitable for total protein extraction from tea leaves,and met the requirements for Western-blot analysis,together with short time,high concentration,clear electrophoretic bands,and no contaminated background in SDS-PAGE.Nine kinds of dehydrin-like prteins in tea plant with the molecular weights ranging from 14-95 kD,were found in different seasons and during overwintering.The expressions levels were relatively stable in the 6 kinds of dehydrin-like proteins (molecular weights 95,65,48,37,34 and 14 kD).The 58 kD dehydrin occurred only in winter,and showed a continuous expression in overwintering period,which achieved the highest expression in February.The highest expression of 28 kD dehydrin was found in winter,whose variation pattern was in accordance with the cold resistance for tea plant.The 21 kD dehydrin expression level was higher in summer and the later period of overwintering.It provided that the three dehydrins (58,28 and 21 kD) might play important roles in stress tolerance for tea plants.

Abstract:Leaf color mutant is an ideal material for analyzing plant photosynthesis mechanism.Agronomic traits,photosynthetic pigment content,photosynthetic parameters and chloroplast ultrastructure of wheat mutant LF2090 with yellow green-revertible flag leaf were investigated,while the wild type H261 was selected as control.The results showed that the content of chlorophyll-b in mutant had a significant reduction in the flag leaf yellowing period,the number of chloroplasts and grana were also reduced,but photosynthetic rate did not change significantly.While,the pigment content,CO₂ concentration and photosynthetic rate of the mutant all dropped dramatically in the flag leaf green-revertible stage and most of grana in the chloroplast were disappeared,however,the relative content of chlorophyll-b was increased.The close of stomatas in the LF2090’s flag leaf is the main reason to reduce the photosynthesis rate and the index of agronomic traits;the decrease of pigment content,which resulted in the abnormal chloroplast structure,also affects the photosynthetic rate.The change of proportion between chlorophyll-a and chlorophyll-b causes leaf color change from yellow to green.

Abstract:This research used strawberry ‘Benihoppe’ (Fragaria ananassa Duch.‘Benihoppe’) as test materials,using the injection method to inject methyl jasmonic (MeJA concentration is 400 μmol/L) on the 15th day after flowering.We analyzed the effects of MeJA on strawberry fruit development and its related gene expression,to reveal the role and its molecular mechanism in strawberry fruit development and mature regulation.Results show that:(1)with MeJA treatment strawberry fruit,fruit turn red and mature period significantly advanced than control,an average of 4 days in advance;(2)with MeJA treatment,jasmonic acid (JA) synthetic gene FaOPDA1 expression quantity rise rapidly during fruit mature period;(3)FaOPDA1 gene over-expression in strawberry fruit can also promote the strawberry fruit ripe in advance for 3 to 5 days.Meanwhile FaOPDA1 gene over-expression can induce a series of mature related gene expression and promote the strawberry fruit mature in advance.

Abstract:The experiment was carried out by ‘Xinxiaqing 2’ and ‘Xinaiqing’ in climate chambers and studied the influence of seeding growth,physiochemical substance and active oxygen metabolism between the infection clubroot disease (level 3) and not affected clubroot disease (level 0) in pak-choi(Brassica campestris ssp.chinensis Makino) by being taken artificial inoculation method.The results showed that:(1)after infected clubroot disease,pak-choi-seedling growth,the shoot fresh weight and the chlorophyll content decreased;while the ratio of root-top(R/T) increased.With more seriously infected clubroot disease,the seeding-growth was restrained significantly,and ‘Xinxiaqing 2’ was more seriously than ‘Xinaiqing’.(2)The osmoprotectants,such as soluble protein,soluble sugar,free amino acid in leaves and proline in roots and leaves decreased,while the malondialdehyde (MDA) content in leaves and roots increased.The changes of osmoprotectants in ‘Xinxiaqing 2’ infected clubroot disease were larger except free amino acid content.(3)The NO₃^- content,activities of nitrate reductase(NR) and glutamine synthetase(GS) of plants infected disease become low.(4)Under clubroot disease stress,the superoxide dismutase (SOD),peroxidase enzyme (POD),catalase (CAT) and ascorbic acid peroxidase (APX) activities in leaves were also decreased,and the SOD,POD and CAT activities in roots were reduced more than that in leaves.Except CAT,the reduced degree of ‘Xinaiqing’ was blower than ‘Xinxiaqing 2’.Obviously,the osmoprotectants content,active oxygen metabolism,ability of using nitrogen and light were affected by clubroot disease,and membrane lipid peroxide were increased.All of the above,it was found that ‘Xinxiaqing 2’ was more seriously influenced by the clubroot disease than ‘Xinaiqing’,and the ability of photosynthesis,absorption,antioxidant and osmoprotic adjustment was depressed by clubroot disease,and the whole plant was sick to grow.Soluble protein and MDA contents,the activities of antioxidant enzymes can be used as early screening physiological indexes of clubroot disease.Comparing with normal plants,clubroot disease resistance of ‘Xinaiqing’ was higher than ‘Xinxiaqing 2’.

Abstract:To explore the UV-B ultraviolet irradiation treatment on the major fruit quality and related enzyme activities in different developmental stages of blueberry,we chose Northland as plant material.The radiation time was 5 min,10 min and 15 min,respectively,and taking no irradiation as control.The result shows that:(1)with UV-B treated young fruit of blueberries,the soluble sugar content significantly increased 47% compared with control by 5 min treatment.The PAL activity increased the most significantly by 10 min treatment.The total phenols and anthocyanin accumulation increased 36% and 31% comparing with the control by 15 min treatment,but flavonoid content and CHI activity reduced significantly.(2)With UV-B treatment ginkgo blueberry,the flavonoids and CHI activity increased significantly by 5 min treatment.The soluble sugar and total phenolic contents increased 25% and 18% than the control by 10 min treatment.The anthocyanin and PAL activity increased the most significantly by 15 min treatment reaching at 48% and 151% comparing with the control.(3)With UV-B treated verarison blueberries 10 min,the soluble sugar and flavonoid contents decreased and the other material content increased significantly.(4)UV-B treatment did not change the regularization during the fruit development of the contents of soluble sugar,total phenols,flavonoids,anthocyanins,and PAL,CHI.(5)The activity of PAL was positively correlated to soluble sugar,total phenolic and flavonoid accumulation.But the activity of CHI was only positively correlated to soluble sugar.Research shows UV-B treatment made soluble sugar content increase at low dose and decrease at high dose.UV-B irradiation could promote the accumulation of total phenols,anthocyanin and flavonoids during ginkgo blueberries,decrease the CHI activity in young fruit,increase the PAL and CHI activities in ginkgo and verarison fruit,also could make positive influence about the major quality of blueberry.

Abstract:In order to clarify the adaptable difference of different drought resistance cotton varieties under drought stress,we took ‘Xinluzao 50’(drought-tolerant) and ‘Xinluzao 27’(drought sensitive) as the material in this test.The active oxygen species generation,electrolyte leakage,antioxidant enzyme activity change,and the expression profiles of some antioxidant enzymes genes,osmotic regulation genes,transcription factors were analyzed under drought stress.The results showed that:(1)the conductivity and MDA content in cotton leaves increased gradually with drought stress strengthen,and recovery after rehydration;the antioxidant enzyme activities of drought-tolerant variety ‘Xinluzao 50’ significantly higher than that of drought sensitive variety ‘Xinluzao 27’ after drought stress 6 and 8 days.(2)Gene expression profiling under drought and rewater treatment showed that cotton superoxide dismutase (GhSOD) only expressed under drought stress and had no difference between two varieties,GhBADH,GhNCED,GhP5Cs and transcription factors GhPHD1,GhPHD5,GhPHD6,GhPHD10 in drought-tolerant variety ‘Xinluzao 50’ had higher expression level than that in drought sensitive variety ‘Xinluzao 27’.The results demonstrated that drought-tolerant variety had lower active oxygen content,conductivity and MDA content,higher antioxidant enzymes activity,and the expression of drought relate genes had higher level compared with drought sensitive variety under drought stress.

Abstract:It has been established that extracellular ATP (eATP) is an important extracellular molecule required to regulate many physiological responses of plants.This study investigates the effects of eATP on the operation of photosystem Ⅱ and the allocation of absorbed light of bean (Phaseolus vulgaris L) leaves under low temperature.The results showed that although low temperature did not have significant effect on the potential maximal photochemical efficiency of PSⅡ(F_v/F_m),low temperature decreased the values of the effective photochemical quantum yield of PSⅡ [Y(Ⅱ)].Further works showed that low temperature decreased the fraction of photochemical efficiency (P) but increased the fraction of antenna heat dissipation (D) and excess energy (E).The level of eATP decreased under low temperature.When the application of exogenous ATP alleviated the decreases of the eATP level under low temperature,the values of Y(Ⅱ) and P were significantly increased,while the values of D and E were decreased.These results indicate that low temperature caused a decrease in the operation of the PSⅡ photochemistry and caused an increase in dissipation of light energy,and eATP could have function in enhancing the performance of PSⅡ photochemistry and decreasing the dissipation of light energy under the condition of low temperature.

Abstract:In this study,the effects of mild(900 mL),moderate(400 mL),severe(300 mL) and CK(1 200 mL) drought stress and rewatering on CBF₁ transgenic cotton (24C-1) and wild type (TH₁) by different sites of leaf photosynthetic parameter and chlorophyll content changes of vitro leaf in dark conditions,and field experiment at seedling stage,bud stage,flowering stage,the bell stage with water stress treatments on production.The results showed that:(1)From the drought stress with different times to re-water 3 d,the net photosynthetic rate(P_n) and maximal photochemical efficiency(F_v/F_m) showed a trend of increasing firstly,decreasing then.Leaf retain number were significantly higher than that of wild type plant,at the top of the leaves is greatly damage to compare middle leaves under drought stress;with the stress time extended that Chl a,Chl b contents decreased,the decreased rate were significantly higher than that of wild type plant.(2)For the date of field experiment compared with normal irrigation treatment water stress at the seedling stage,bud stage,flower stage,bell stage the lint yield,seed index,seed quality,plant height of cotton decreased significantly,transgenic and wild type of the seed cotton yield reduced by 78.4%,55.1%,12.7%,8.3% and 80.4%,55.4%,19.2%,14.4%,respectively.The cotton yields of different stages have been affected by the water stress.But transgenic cotton yields are still significantly higher than that of wild type.These results demonstrated that the CBF₁ gene expression enhanced the growth and development of the transgenic cotton plant,and indicated that the CBF₁ transgenic cotton could improve the drought resistance.

Abstract:We evaluated the change mechanisms of Pistacia weinmannifolia leaves fast chlorophyll under water stress condition,which is typical species in dry and hot valley.The present study was designed to measure fast chlorophyll fluorescence under 5 relative soil water contents 50%(C₁),30%(C₂),20%(C₃),10%(C₄)and 5%(C₅).The results showed:(1)under the water stress condition,oxygen evolving complex subject of P.weinmannifolia is damaged hardly,and a large number of photosynthetic electron transport chain Q_A^- are accumulated,electron transfer capability and quantum yield were lower.(2)The minimum and maximum points of ABS/CS,TR_o/CS,RC/CS,DI_o/CS and ABS/RC,ET_o/RC,DI_o/RC,M_o arrived under C₃ level,the minimum and maximum points of V_j and Ψ_o,ΨE_o,ET_o/CS arrived at C₂ level,ET_o/RC are increased with the relative soil moisture content lower.(3)P.weinmannifolia PI_ABS (photosynthetic performance index) is more sensitive than F_v/F_m (φp_o).From this reseach,it can be seen that P.weinmannifolia has launched a corresponding self-defense mechanism,plastoquinone Q_A are slowing the reduced rate,electronic hindered in the transfer process under the C₂ level.The antenna system of P.weinmannifolia has been damaged,which leading to reduced absorption of light energy and dissipation of excessive excitation energy in time under the C₃ level,and reduce the OEC damage caused by the reaction center,only be lifted at C₄,and improve the P.weinmannifolia photosynthetic efficiency.Water stress will impact the P.weinmannifolia physiological,which will grow health under the relative soil water content keep 10%,the P.weinmannifolia can adapt the drought conditions.

Abstract:6-7 years of olive trees were selected as materials,and three soil moisture conditions of full irrigation (W_CK),2/3 irrigation (W₁) and 1/3 irrigation (W₂) were set in this paper.We investigated the influences of soil-loosening on the physicochemical index,soil fertility related enzyme activities of olive rhizosphere soil,olive resistance physiology indexes and root activity under drought stress,explored the physiological mechanism of olive oil to improve soil drought resistance,so as to offer theoretical and technical support for the production of oil olive.The results showed that:(1)with the decrease of irrigation amount,superoxide anion production rate and MDA and H₂O₂ contents of the olive leaves increased,which indicated that the leaves suffered from the oxidative stress and even lipid peroxidation.However,the soil-loosening inhabited their growth and the stability index of cell membrane was decreased.(2)After soil-loosening treatment,POD and CAT activities were significantly increased except for SOD activity and glutathione content.(3)The activity of soil enzymes and water content in the rhizosphere soil of olive increased,while the soil’s pH value decreased through the treatment of soil-loosening.All the above changes should have positive effects on mineral nutrition and water absorption,especially under the condition of drought stress caused by insufficient irrigation.(4)Chlorophyll content and root vigor also increased with soil-loosening treatment.In a word,soil loosening enhanced the enzymatic and non-enzymatic antioxidant system,improved the ability of the osmotic adjustment and enhanced the root activity through the improvement of the olive rhizosphere microenvironment,then enhanced the olive’s drought resistance as a whole.

Abstract:Plant adaptation strategies to prolonged drought are drawing extensive attention due to climate change.Periploca sepium is a native and widespread species in drought-prone regions.To understand plant survival and recovery mechanisms from extreme drought,we investigated the morphology,solutes accumulation and antioxidant enzymes of P.sepium under progressing drought stress (PD) and during subsequent re-watering.Three prolonged constant drought stresses (PCD) were set as comparisons.For PCD,soil moistures were kept at 80%,55% and 35% of field capacity water content,respectively.For PD,seedlings were dehydrated for 15-54 d to reach various drought intensities.(1)Under PCD,P.sepium could adapt and enter into a new steady physiology.Reduced canopy size and higher level of soluble sugars (TSS) and peroxidase (POD) contributed mainly to its drought resistance.(2)Contrast to PCD,P.sepium under PD showed ever-changing morphology and physiology.In drought phase,high accumulated proline,free amino acids (FAA) and TSS conferred tolerance before leaf death.As drought intensifying,morphological changes especially the well-organized organ senescence played pivotal roles in P.sepium survival.(3)When re-watered,new buds appeared and grew significantly faster than normal plants.Surprisingly high level of proline,FAA,superoxide dismutase (SOD) and POD indicate highly active physiology in new buds.Proline,FAA concentrations as well as SOD and POD activities declined rapidly with plant reviving,indicating their important roles in plant recovery and compensatory re-growth.These results exhibit contrasting resistant mechanisms under PCD and PD,and provide new information on plant recovery mechanisms from extremely drought.

Abstract:Spacer length (the distance between connected ramets) may cause significant effects of physiological integration,but lack of correlated studies.The change of antioxidant system and photosynthetic pigment may affect plant response to the moisture heterogeneity,but lack of related research also.The experiment with connected Indocalamus decorus clonal ramets under 3 substrate relative water content [high,(90±5)%;intermediate (60±5)%;low (30±5)%] and 2 water potential gradient (H-L and M-L),the antioxidant enzyme,content of soluble protein,MDA and photosynthetic pigment of three spacer length (10,25 and 40 cm) connected clonal ramets were determined.The results showed that:(1)CAT activity,leaf relative electric conductivity and MDA content increased at first and then decreased,while SOD activity presented a trend just on the contrary to the CAT activity with the increasing of treatment time.Overall,POD activity and photosynthetic pigment content present “N” type,while soluble protein content showed inverted “N” trend with treatment time extended.(2)Water potential gradients and spacer length affected the water physiological integration of Indocalamus decorus clonal ramets.Antioxidant enzyme activities,soluble protein and photosynthetic pigment contents of low water potential receptor ramets decreased,while leaf relative electric conductivity and MDA content increased significantly with the water potential difference increasing and spacer distance shortening between I.decorus ramets.The water potential is higher and the spacer is longer,the antioxidant enzyme activities,soluble protein and photosynthetic pigment contents of donor ramets are higher and the leaf relative electric conductivity and MDA content are lower.All results indicated that water transfer from high water potential ramets to low water potential ramets would be taken place in I.decorus clonal system under heterogeneous water environment.The water potential difference between ramets is bigger,and the length of spacer is shorter,the intensity of physiological integration is stronger,the benefit of receptor ramets is more obvious.Moreover,with treatment time extending,water integration intensity between connected clonal ramets increased in early time,but it weakened later,which reflected that the consumption-benefit effect of donor ramets and receptor ramets changed in time dimension,and the change was much more obvious in early stage of the treatment.The research provided a theoretical reference for artificial water management of commercial bamboo forests.

Abstract:In order to revealed the plant community stability on the habitat of giant panda in Qinling Mountains we set two line transects between the altitude of 900-3 071 m in the field,and the standard plots (20 m×25 m) were investigated on transects in Foping and Changqing Nature Reserves.Based on analysis of survey data,community stability of 16 representatives and typical community types were evaluated by subordinate function of fuzzy mathematics.The evaluation index included the regeneration of dominant species,stand qualities,diversity,community complexity,soil fertility and protective degree.The results showed that:(1)according to the analysis of regeneration ability of dominant species in different community tree layer,the quantity of undergrowth seedlings and young trees of Quercus variabilis were the highest and the subordinate function value was largest,showing the regeneration ability was best.However,none of seedlings and young trees grew under the Pinus armandii forest and the subordinate function value was lowest,showing the regeneration ability was worst.(2)According to the analysis of quality of forest land in different communities,the average subordinate function value of growing stock volume and the quality of forest land in mixed forest of Pinus armandii and Pinus tabulaeformis were best.However,the average height and litter depth were the lowest in mixed forest of Pinus tabulaeformis and Quercus aliena var.acuteserrata,the quality of forest land was worse.(3)According to the analysis of forest soil fertility,the membership function of Larix chinensis forest was highest and soil fertility was higher,whereas the subordinate function value of Castanea mollissima and Betula luminifera were lower and the soil fertility was lower too.(4)According to the species diversity of forest land in different communities,the subordinate function value of Tsuga chinensis was the highest which showed a outstanding species diversity,and the subordinate function value of Larix chinensis was lower,showing a lower species diversity.(5)According to the complexity of forest land in different communities,the subordinate function value of three aspects of complexity in Tsuga chinensis was relatively higher which showed high community complexity,whereas the subordinate function value of Larix chinensis was lower and the community complexity was lower too.(6)According to the protective degree of forest land in different communities,the protective degree of Larix chinensis and Abies fargesii were high for they were distributed in core region of protected area,while the protective degree of Castanea mollissima and Betula luminifera were low because of the marginal division of protected area.(7)The subordinate function value showed that the community stability can be arranged as an order of Tsuga chinensis＞Quercus glandulifera var.brevipetiolata＞Populus purdomi＞Pinus armandii＞Quercus aliena var.acuteserrata＞Abies fargesii＞Betula platyphylla=Betula albo-sinensis＞Pinus tabulaeformii+Pinus armandii=Betula albo-sinensis var.septentrionalis＞Pinus tabulaeformis+Quercus aliena var.acuteserrata＞Pinus tabulaeformis＞Larix chinensis＞Quercus variabilis＞Castanea mollissima＞Betula luminifera from high to low.

Abstract:Zanthoxylum piperitum (L.) DC.and Cornus kousa subsp.kousa F.Buerger ex Hance were reported as two newly recorded species from China,all found in Zhoushan islands,Easten Zhejiang,China.The morphological descriptions and photos were provided.The voucher specimens were preserved in the herbariccm of Zhejiang Agriculture and Forestry University(ZJFC).

Abstract:In this study,Acarospora dispersa H.Magn.and A.obnubila H.Magn.collected from Miquan forestry in eastern Tianshan Mountain are reported as new to China.The descriptions on morphological,anatomical,chemical and ecological features of the species are given with color photos.The samples are preserved at the Northwest Arid areas lichen Herbarium of Xinjiang University.

Abstract:As one of the major types of repetitive sequences,transposable elements (TEs) are the most abundant DNA in high plants,and have been recognized to play important roles in altering gene structures,regulating gene expression,affecting genome evolution and creating new genes.Helitron TEs belong to DNA transposons,and have been found to frequently capture gene or gene fragments,and often insert into genes or nearby during transpositional process.Therefore it was believed to be important in genomic composition,genome evolution,and altering genotype and phenotype.In this review,we introduced the recent progress on helitrons,and then summarized the recent progress on the structural characteristics,the methods for identification and classification,the DNA content in genomes,the distribution across chromosomes,the transpositional replication and the capture of gene fragments.Finally,we discussed the problems for the current helitron study,and the perspectives for future research.