Abstract:The NHCC004 of Brassica campestris was used as the experimental material. A pair of primers were designed according to the BcMAF2 gene sequence of NHCC004. The results showed that：（1） BcMAF2 contained an open reading frame（ORF） of 588 bp which encodes 196 amino acids. The comparison of amino acid sequence of BcMAF2 protein with other species showed that the BcMAF2 gene had a highly conserved domain with other species.（2） The subcellular localization vector pEarleyGate101BcMAF2YFPHA was expressed transiently in the leaves of Nicotiana tabacum via Agrobacterium tumefaciensmediated method. The results showed that BcMAF2 protein was located in the nucleus, acting as a transcription factor. （3）The plant expression vector of pEarleyGate101BcMAF2YFPHA and then introduced into Arabidopsis by dipping method and 5 strains of overexpression lines were obtained by Western blot. Late bolting was observed in the line 8 and 10 transgenic Arabidopsis thaliana. This research predicted result shows that BcMAF2 participates in vernalization pathway of flowering in plants.

Abstract:In this study, a CsBAP1 gene was cloned from the cDNA of ‘Longjing 43’ based on the transcriptome data of tea plant. We analyzed its protein sequence characteristics and gene expression patterns. In addition, the expression profiles of the CsBAP1 gene in different tissues and under extreme temperatures and hormone treatments in tea plant was analyzed by quantitative real time PCR. (1) Sequence analysis showed that the length of the CsBAP1 open reading frame (ORF) is 543 bp, encoding 180 amino acids and contains a highly conserved region called C2 domain. Protein analysis suggested that the CsBAP1 is a hydrophilic protein with the theoretical relative molecular weight 19 398 Da and the theoretical isoelectric point 9.30. Secondary structure prediction showed that the CsBAP1 protein consists of 8.89% αhelix, 7.78% βturn, 35.56% extended strand and 47.78% random coil. The threedimensional structures indicated that CsBAP1 protein contains αhelix and βstrands. (2) The expression profiles of the CsBAP1 was detected in flower, floral buds, young leaves, mature leaves and senescent leaves by the RTqPCR. And the highest expression level was detected in the senescent leaves. The expression level of CsBAP1 was downregulated by ABA, IAA, MeJA, GA₃, and SA treatments, respectively. The expression level of CsBAP1 was upregulated under high temperature (38 ℃), low temperature (4 ℃), drought (200 g·L^-1 PEG), and highsalinity (200 mmol·L^-1 NaCl) treatments, respectively. These results provide a foundation for the function study of CsBAP1 gene in tea plants.

Abstract:In order to understand the sequence characteristics of miRNA precursors (premiRNAs) and their expression in different tissues and pseudobulbs infected by soft rot in Oncidium hybridum, we analyzed 25 premiRNAs and 15 mature sequences in the transcriptome and miRNA database of Oncidium. And the expression of 25 premiRNAs in different tissues and pseudobulbs infected by soft rot pathogen were analyzed by realtime fluorescence quantitative PCR (qRTPCR). The results showed that：（1） 25 premiRNAs sequences of Oncidium could be divided into 13 families, including 15 mature sequences.（2）Mfold prediction results showed that all of the Oncidium 25 premiRNAs could form a typical stable stem loop structures with a minimal folding free energies (dG) from -32.04 to -120.98 kal/mol. （3） Sequence alignment analysis showed that there was a conserved region of about 20 bases in the same family of precursors and mature sequences, suggesting that this region may be mature miRNAs. Among them, miRNAs from 10 of 13 precursor families can be fully localized in their precursors.（4） qRTPCR results showed that premiRNAs such as miR159unigene0037857, miR167unigene0011236, miR167unigene0002619, miR169unigene0022341, miR172unigene006514, miR396unigene19032, miR398unigene0009996, miR2950unigene0006151 and miR2950unigene0006422 accumulated in leaf may be helpful for the morphogenesis of the leaves. miR162unigene0003615, miR162unigene0013441, miR166unigene 0011870 and miR168unigene0009958 were highly expressed in roots and leaves, which may be beneficial to the development of roots and leaves. Meanwhile, the abundance expression of miR171unigene 0045985, miR396unigene0011179 and miR396unigene0011180 in roots and pseudobulbs may be beneficial to the development of roots and pseudobulbs.（5） In pseudobulbs infected by soft rot pathogen, the expression levels of miR159unigene0037857, miR167unigene0011236, miR396unigene0011179, miR396unigene0011180, miR396unigene0019032 and miR845unigene0012489 showed atrend of decrease and reached the lowest level after 12 h infection. The expression of miR162unigene0040566, miR166unigene0011870, miR168unigene0009958 and miR171unigene 0045985 increased in pseudobulbs infected by soft rot pathogen after 4 h, and then downregulated. The expression of miR162unigene 0003615, miR167 unigene0002619, miR168 unigene0047942, miR169unigene0022341 and miR845unigene0012489 showed the tendency of first decrease and then increase in the process of pathogen infection, and reached the minimum after 8 h. The above results showed that different members of the 13 families of the premiRNAs of Oncidium are highly conserved and specific in their evolutionary processes, and may be widely involved in the growth and development of different tissues and in response to soft rot pathogen infection in Oncidium.

Abstract:In this study, we cloned a dehydrin encoding gene LcDHN3 from Leymus chinensis. The sequence analysis shows that the open reading frame of LcDHN3 is 501 bp and encodes 167 amino acids, molecular weight is 17.01 kD, theoretical pI is 8.05, contains dehydrin superfamily domain, and one Ysegment, one Ssegment and two Ksegments, belongs to YSK2 type dehydrin. Subcellular localization predicts LcDHN3 may localized in both cytoplasm and nuclei. Multiple alignment of homology sequences showed that the identity of LcDHN3 with DHNs from other plants was 84.27%. Phylogenetic analysis revealed LcDHN3 had the closest genetic relationship with Hordeum vulgare DHN. The transcripts of LcDHN3 were induced by different abiotic stresses, including drought, cold, heat, NaCl, high pH and wounding, as well as ABA and JA treatments. These results indicate that LcDHN3 involved in the signal transduction pathway of L. chinensis in response to abiotic stresses.

Abstract:The fulllength cDNA sequence of the carotenoid cleavage dioxygenases CsCCD1 and CsCCD4 (NCBI accession number：MH119136 and MH119137) were cloned, respectively, by homology cloning techniques from the leaves of tea cultivar ‘Tieguanyin’. The sequence analysis showed that the length of CsCCD1 was 1 766 bp, which contained a 1 641 bp ORF encoding 545 amino acids. Prediction results showed that it did not contain the transmembrane structure and signal peptides, and had high probability to locate on the cytoplasm. Additionally, the length of CsCCD4 was 1 942 bp, which contained a 1 842 bp ORF encoding 612 amino acids. Prediction results showed that it did not contain the transmembrane structure but had a Nterminal chloroplast targeting transit peptides. Phylogenetic tree analysis showed that both CsCCD1 and CsCCD4 could be clustered into the same category with RjCCD1 and RjCCD4 of Rhododendron japonicum, respectively. Tissuespecific expression pattern analysis showed that both CsCCD1 and CsCCD4 were highly expressed in leaf, stem and flower. During the greenmaking procedure of Oolong tea, expression of gene CsCCD1 and CsCCD4 downregulated from leaves to solar withering. Expression of gene CsCCD1 upregulated from first tumblings to second tumblings, downregulated rapidly after third tumblings. Expression of gene CsCCD4 upregulated after first tumblings, and then drops rapidly. Indicate that they might be related to aroma formation in greenmaking procedure of Oolong tea.

Abstract:In this experiment,PCR and RACE methods were used to clone and bioinformatics was used to analyze the ethylene insensitive 2 (EIN2) gene of Oncidesa Gower Ramsey. The qRTPCR technique was used to analyze the different tissue sites and different flowering stages of Oncidesa. The results showed that: (1) The EIN2 gene of Oncidesa, named OnEIN2 (MH497388) was successfully cloned; the cDNA of OnEIN2 fulllength was 4 177 bp, contains a 3 879 bp open reading frame（ORF）, encoding 1 292 amino acids, the noncoding region of 3′ and 5′ were 208 bp and 90 bp. (2) Bioinformatics analysis showed that OnEIN2(molecular formula: C₆₄₀₆H₉₉₈₈N₁₆₇₀O1897S₄₇) was an unstable hydrophobin protein containing a transmembrane domain; the molecular weight of the protein was 142.22 kD and the theoretical isoelectric point was 5.80. Multiple sequence alignment and phylogenetic analysis showed that the similarity of OnEIN2 was highly similar to EIN2 in Dendrobium catenatum (up to 81.98%), and the genetic relationship between them was the closest. (3) Quantitative realtime PCR showed that OnEIN2 expresses in roots, stems, leaves and flowers; with the highest expression level in flowers and the lowest level in stems, while the expression level was the highest in different flowering stages during the blooming period, followed by senescence stage. This study showed that OnEIN2 may play an important role in flowering and senescence.

Abstract:Trehalose6phosphate synthase gene TPS is one of the key genes for the synthesis of trehalose. In this study, the homologue of TPS5 was isolated from Petunia hybrida, which was named PhTPS5. The open reading frame（ORF）of PhTPS5 was 2595 bp and encoded a protein of 864 amino acids. The molecular formula of PhTPS5 protein was assumed to be C₄₃₆₃H₆₈₂₅N₁₁₇₃O₁₂₈₉S₃₇. Tissuespecific expression analysis showed that PhTPS5 had the highest expression level in roots and the lowest in leaves. After 6 h of decapitation, PhTPS5 expression was significantly promoted, and the expression level decreased significantly at 24 h. The application of auxin to the top could effectively inhibit the regulation to PhTPS5. The expression level of PhTPS5 was significantly upregulated after 6 h of cytokinin treatment, and decreased with the increase of treatment time. This study laid a theoretical foundation for further revealing the regulatory mechanism of the TPS pathway in the shoot branching of petunia.

Abstract:Amygdalus mongolica is a Tertiary relict plants widely distributed on the arid region of Northwest China, noncoding chloroplast DNA was amplified and sequenced in 324 individuals from 17 populations sampled from the entire distribution range of A.mongolica. The main results are as follows: (1) the length of trnHpsbA sequence was 350 bp, a total of 63 polymorphic sites were identified and 9 haplotypes were recovered. Total genetic diversity was 0.758, average genetic diversity within populations was 0.203. Populations from the Helan Mountains and southern foot of Yin Mountain owned high haplotype diversity and nucleotide diversity and fixed more private haplotypes, which suggested that the eastern margin of the Helan Mountains and southern foot of Yin Mountain were important refugium during the Quaternary glaciation. (2) AMOVA analysis suggest that 83.84% of total variation existed among populations and 16.16% existed within population, there is no significant phylogeographic structure (N_st=0.733, G_st=0.655, P>0.05). The natural populations of A.mongolica could be divided into eastern group and western group based on the geographical distribution and network of haplotypes, there were no shared cpDNA haplotypes between the two groups. The high level of genetic differentiation and genetic diversity were found based on the population genetic analysis, and no significant phylogeography was existed in the populations of A.mongolica. (3) The populations of A.mongolica have occurred the expansion events during the interglacial periods or postglacial. Founder effect occurred during the population expansion which lead to only one haplotype in the most populations.

Abstract:In this study, we used 5 Osmanthus fragrans varieties as materials, with Hoagland culture liquid as control, 2 NaCl contents (70 and 100 mmol/L) as treatments, and observed the ultrastructure characteristics of different varieties with by TEM and SEM after 10 d treatment, to clarify the anatomical structure response mechanism of O. fragrans cultivars to NaCl stress tolerance. The results showed that: (1) TEM analysis showed that the chloroplast structure in mesophyll cells of 5 varieties are destroyed in different degrees with the increase of NaCl concentration; the nucleus structure of 5 varieties maintain normal in 70 mmol/L NaCl; in 100 mmol/L NaCl, chromatin within the nucleus begins to degrade. With the NaCl stress strengthening, osmiophilic particles in the thylakoid lamellar structure of the 5 varieties increase significantly. In terms of membrane structures, the mesophyll cells of ‘Daye Yingui’are damaged most seriously, chloroplast membranes are damaged so that the basic shape cannot be recognized. (2) SEM photos indicated that the stomatal density on leaf surface of 5 varieties increases gradually while the opened porosity density decrease with the increase of salt concentration. The proportion of palisade tissue accounting for leaf thickness of ‘Daye Yingui’, ‘Xiao Qiufeng’ and ‘Wanzi Yingui’ increase at first then decrease with the increase of salt concentration of ‘Huangchuan Jingui’ and ‘Zigeng Ziyingui’. It proves that the higher the salt concentration was，the more obvious of the damage effect was. This experiment can preliminarily judge that the salt stress tolerance of ‘Daye Yingui’, ‘Xiao Qiufeng’ and ‘Wanzi Yingui’ is slightly higher than that of ‘Huangchuan Jingui’ and ‘Zigeng Ziyingui’.

Abstract:Based on stereomicroscopic and scanning electronic microscopic observation, we studied the hair morphology and distribution on leaf of 34 species of Astragalus Sect. Trachycersis Bunge from China in order to identify their variation pattern and taxonomic significance. The results showed that hairs are distributed on both upper and lower leaf surfaces of all studied species except for A. galactites, in which hairs are only on lower surface of leaves. The distribution, morphology, length and arm ratio of hairs are varied in different species. Haris are medifixied, hollow, appressed or spreading, densely to sparsely papillose on hair surfaces. Among them, appressed hairs are inflated on base of attachment, gradually thinner from middle to both ends, while spreading ones generally are slender filiform or linear, smooth or with striation. In our point, those appressed, short and straight, smooth with densely papillose, and with small arm ratio, flat hairs are ancestral characters, while those spreading, long and dense, filiform or linear, with striate ornamentation and sparsely papillose on surface, and with big arm ratio are advanced ones. On the basis, we discussed taxonomy of some related species in this section.

Abstract:In this study, Luculia gratissima ‘Xiangfei’ cuttings were selected as material. The floral reaction was explored by different photoperiod treatments and transferring plants between short day and long day conditions. Meanwhile, the process of flowerbud differentiation under different photoperiods was observed by paraffin section. This study attempted to provide a theoretical basis for flowering control and cultivation of potted plants in L. gratissima ‘Xiangfei’. The results indicated that: (1) L. gratissima ‘Xiangfei’ is a qualitative or obligatory shortday plant, the critical daylength is about 14 h, the suitable daylength for flowering is 10-12 h, and the limited inductive photoperiod is 30 shortday. (2) Under the inductive photoperiod, the period of flower bud differentiation included undifferentiation phase, bract primordium differentiation phase, inflorescence or small flower primordium differentiation phase, perianth primordium differentiation phase, stamen primordium differentiation phase, and pistil primordium differentiation phase. After induced photoperiod treatment for 16 d, all plants completely achieved the transition to flowering. After treatment for 30 days, the flower bud differentiation of all plants was at the stage of perianth primordium formation, the floral determination reached a stable maintenance state and the floral reversion would not occur when transferred to the noninductive photoperiod. (3) Under the uninduced photoperiod of 4 h dark interruption, buds of plants were always in undifferentiation phase of vegetative growth.

Abstract:To reveal the regulation mechanism of spatial arrangement and flowering dynamics of plant flowers and the ecological strategy of avoiding geitonogamy, we observed and analyzed the morphological structure, flowering dynamics and pollination biology of the inflorescence of Beesia calthifolia (Maxim.) Ulbr. The results show: (1) the structure of inflorescence of B. calthifolia is elaboration and there are units of cyme composed of three flowers arranged in sequence on the main inflorescence axis. The long distance between the units is not suitable for insects foraging by crawling. (2) The racemes of B. calthifolia opening one by one from the base to the top and the top flowers on a single cyme opening first (usually the top 6-8 cymes open at the same time) prevent blooming of a large number of singleflowered inflorescences as far as possible. (3) Flower is white and its pollen is the only attractant for pollinators. As the most important pollinating insect of B. calthifolia, Baccha maculata can forage pollen by selecting filaments as force point. After foraging a single flower in one inflorescence, they turn to another inflorescence soon. Therefore, the space design and flowering time dynamics of inflorescence of B. calthifolia can reduce the frequency of insect visiting different flowers on one plant as low as possible.

Abstract:The changes of reactive oxygen species, antioxidant enzyme activity, and antioxidant substance contents in roots and leaves of Pugionium cornutum (L.) Gaertn. and P. dolabratum Maxim. were measured with potculture drought stress in greenhouse, and the drought resistance of them were evaluated by the method of membership function and drought resistance coefficient. The results showed that: (1) with the increase of drought stress, the O^-·₂ generation rate and the contents of ·OH, H₂O₂ and MDA increased in roots and leaves of P. cornutum and P. dolabratum. Moreover, P. cornutum produced more ROS and MDA than that of P. dolabratum under drought stress. (2) With the increase of drought stress, the activities of POD, APX and GST increased firstly and then decreased, the activity of CAT increased in roots and leaves; The activity of SOD in leaves, GR and GPX in roots decreased firstly and then increased, the activity of GR in leaves increased firstly and then decreased, but the activity of GPX in leaves, SOD in roots increased; The activities of SOD, POD and CAT in roots and leaves of P. dolabratum were higher than that in P. cornutum. (3) The content of AsA increased firstly and then decreased, the content of GSH increased, and the content of CAR decreased in roots and leaves; The content of VE in leaves increased, the content of VE in roots decreased; P. dolabratum made more AsA and GSH, the AsAGSH cycle system in P. dolabratum could remove more ROS than that in P. cornutum. (4) The TAOC (total antioxidant capacity) increased in roots and leaves; The antioxidant ability of P. dolabratum was higher than that of P. cornutum. We know that drought resistance of P. cornutum were higher than that of P. dolabratum under light drought stress. However, drought resistance of P. dolabratum was higher than that of P. cornutum under moderate and severe drought stress by comprehensive drought resistance coefficient and average subordinate function of reactive oxygen species scavenging system indexes in response to drought stress of two species in Pugionium Gaertn. Under drought stress, the ROS and MDA contents in P. dolabratum were lower than those in P. cornutum, and the most of antioxidant enzyme activities and antioxidant contents in P. dolabratum were higher than those in P. cornutum. The reactive oxygen species scavenging system showed stronger drought resistance in P. dolabratum than those in P. cornutum.

Abstract:The objectives of this experiment were to study the effects of CaCl₂ concentration on N metabolism in roots, stems and leaves of sour jujube under NaCl stress and to determine the ability of exogenous Ca to alleviate NaCl stress in sour jujube seedlings. The jujube seedlings were used as test materials to measured hydrogen peroxide (H₂O₂) and super oxide (O^-·₂) concentrations in the leaves by different concentrations of CaCl₂ (0, 5, 10 and 20 mmol/L) under NaCl stress (150 mmol/L). The activities of nitrate reductase (NR), glutamine synthetase (GS), and glutamate synthase (GOGAT) and the concentrations of free amino acid, protein and NO₃N were measured in roots, stems, and leaves. Principal component analysis was used to select the best physiological indexes for evaluating the ability of CaCl₂ to alleviate NaCl stress in sour jujube seedlings. The results showed that 5 and 10 mmol/L CaCl₂ significantly reduced H₂O₂ and O^-·₂ concentrations in the leaves of NaClstressed sour jujube seedlings. The 5 and 10 mmol/L CaCl₂ treatments significantly increased GOGAT activity in roots and stems. All of the CaCl₂ treatments significantly increased GOGAT activity in leaves. Leaf GS and NR activities were significantly increased by all of the CaCl₂ treatments. Root GS and NR activities were significantly increased by 10 and 20 mmol/L CaCl₂, whereas 5 mmol/L CaCl₂ had no significant effect. Stem GS and NR activities were increased only by 10 mmol/L CaCl₂. All of the CaCl₂ treatments significantly increased protein contents in roots, stems, and leaves. The 10 and 20 mmol/L CaCl₂ treatments increased free amino acid contents in roots and stems, whereas only the 10 mmol/L CaCl₂ treatment significantly increased free amino acids in leaves. The 10 mmol/L CaCl₂ treatment significantly increased NO₃N concentrations in roots and stems. All three CaCl₂ treatments increased NO₃N concentrations in leaves. The 150 mmol/L NaCl stress treatment caused significant peroxidative damage to wild jujube seedlings and inhibited N metabolism. Exogenous CaCl₂ helped the sour jujube seedlings adapt to NaCl stress by promoting the assimilation of NH₄⁺ via the GS/GOGAT cycle in roots and stems and by increasing NR activity and regulating NO₃N transformation rates. The results showed that 10 mmol/L CaCl₂ was the most effective treatment for alleviating NaCl stress in sour jujube seedlings. The GOGAT activity, NR activity, and free amino acid concentrations can be used to evaluate the ability of CaCl₂ to alleviate NaCl stress in sour jujube.

Abstract:In this paper, the strawberry plant growth, physiology, yield and quality were analyzed and compared under the condition of intercropping with corn and continuous cropping, with a purpose of providing the theoretical basis for overcoming the continuous cropping obstacles in strawberry production. Results showed that: (1) the strawberry growth index of intercropping with corn was significantly higher than that of continuous copping, such as the plant height, the root length, the stem diameter, and the weight of strawberry plant. (2) Compared with continuous cropping, the tillage pattern of intercropping with corn could increase the protective enzyme activities of superoxide dismutase, ethanol dehydrogenase and peroxidase. In addition, intercropping with corn could increase soluble sugar content in roots and leaves of strawberry plant, respectively, and make the malondialdehyde content in a relative low level, simultaneously. It means that intercropping with corn could ensure the strawberry plant growth well. (3) Intercropping with corn could reduce the rate of strawberry plants by 28.8%, when they were transplanted at the beginning of autumn, and these transplanted strawberry could be quickly recovered in the field of intercropping with corn, which compared with continuous cropping. (4) The strawberry plant, which intercropping with corn, has the ability to significantly increase their fruit hardness, the single fruit weight, and the yield of single strawberry plant concurrently, but has no significant effect on the soluble content. We can summarize that strawberry continuous cropping obstacles could be overcome by intercropping with corn, and the strawberry plant vegetative growth and the resistance to stress were improved, and the fruit yield and quality were also increased under the intercropping with corn, respectively.

Abstract:To explore the salttolerance and its physiological mechanism of daylily, with the normal nutrient solution as control, the experiment studied the effects of NaCl stress on the growth, lipid peroxidation and organic osmotic substances contents of Datong daylily in sand culture by irrigating the different concentrations (50, 100, 150, 200, 250 mmol·L^-1) of NaCl solution and measuring the growth and physiological indicators at 5, 10, 15, 20, 25 d after treatment. The results showed that: (1) with the increase of NaCl concentration, the root length and root fresh weight were increased and then decreased, the other growth indexes were decreased significantly, and the aboveground water content was relatively stable, and root water content was increased obviously. (2) The contents of chlorophyll a, chlorophyll b and carotenoid in leaves of daylily were decreased obviously with the increase of NaCl concentration. (3) With the rise of NaCl concentration, the MDA content and POD activity were increased drastically, the AsA content was increased within 20 d after treatment, and showed the trend of “increasedecrease” and reached the maximum at 150 mmol·L^-1 at the 25th day. The SOD activity showed the law of “increasedecrease” and reached the peak value at 200 mmol·L^-1 within 10 d after treatment, and was increased significantly with the rise of NaCl concentration after 15 d. (4) With the increase of NaCl concentration, the proline content was increased drastically, the soluble sugar content was decreased obviously, the soluble protein content was increased with the rise of NaCl concentration in short period, and showed the trend of “increasedecrease” and reached the maximum at 150 mmol·L^-1 NaCl after 15 d. The research illustrated that the greater the NaCl concentration, the greater the inhibition degree to the photosynthetic pigment synthesis and the peroxidation damage to the daylily plant. The abilities of antioxidance and osmotic adjustment of plant under stress were increased obviously, but the change could not eliminate the adverse effect by NaCl stress. It made that the growth of daylily plant was reduced significantly. The salttolerance of daylily was very strong, the plant can survive under 250 mmol·L^-1 NaCl stress.

Abstract:In order to provide a theoretical basis for the selection of suitable scionstock combinations of apple in the northwest Loess Plateau, we studied the growth, photosynthetic and fluorescence characteristics of different combinations. Malus halliana (CSHT) and Malus hupehensis (PYTC) were employed as rootstocks, and Malus pumila ‘Yanfu 6’ (Y6) and Malus pumila ‘Nagafu 2’ (C2) were used as scions, and the graft affinity, growth, photosynthesis, chlorophyll fluorescence characteristics and chlorophyll content (SPAD) of four combinations were measured. (1) The grafting affinity of CSHT+Y6 was the highest among four combinations for the diameter ratio was nearest to 1. (2) During the whole growth period, the growth, net photosynthetic rate (P_n), the maximum fluorescence (F_m), and photochemical efficiency (F_v/F_m) in the combinations of two scions on the Malus halliana were significantly higher than that of Malus huphensis, also the intercellular CO₂ concentration (C_i) and the initial fluorescence (F₀) of it were lower than that of M. huphensis. There is no significant difference in the photochemical quenching coefficient (qP) among the four scionstock combinations. (3) When the light intensity was higher in August, the stomatal conductance (G_s) of CSHT+Y6 was significantly higher than that of other combinations. The transpiration rate (Tr) and chlorophyll content (SPAD) of the two scions on the M. halliana were higher than that of M. huphensis. (4) The indices were comprehensively evaluated using the principal component analysis. According to the comprehensive score of the four combinations, the order was from high to low: CSHT+Y6, CSHT+C2, PYTC+C2 and PYTC+Y6. Therefore, the resistance of M. halliana is better than that of M. huphensis. CSHT+Y6, which was a suitable combination in central Gansu province, possessed the highest grafting affinity, the best growth and great photosynthetic capacity.

Abstract:In order to study the effects of soil environment on parasitism and growth of sunflower broomrape (Orobanche cernua), we used sunflower variety “Longshikui No.2”, which is high sensitive to sunflower broomrape, as test material and carried out method of inoculating and indoor culture. The results showed that: (1) soil texture had a significant effect on the parasitism of sunflower broomrape. When cultured for 50 days, the number of unearthed broomrape in sandy loam, loam and clay were 32.2, 19.5 and 4.6, respectively and the average parasite of individual plants was 38.8, 24.0 and 8.2, respectively. It showed that the sandy loam with good permeability was beneficial to the formation and growth of broomrape tumor. (2) Under the condition of sandy loam, with the increase of treatment temperature, both the number of unearthed and the number of parasitic quantities increased first and then decreased. When the incubation temperature was 25 ℃ and 30 ℃, the sunflower broomrape had higher parasitic quantities and growth speed and the number of unearthed broomrape and the average parasite of individual plants was 30.4, 31.6, 39.8 and 39.4, respectively. (3) Under the condition of sandy loam, with the increase of soil moisture, the number of unearthed and the number of parasitic quantities firstly increased and then decreased. The numbers were relatively high when soil moisture was 60% and 70%, the number of unearthed broomrape and the average parasite of individual plants were 32.6, 30.9, 39.9 and 40.9, respectively, but the number of parasites decreased significantly under high humidity condition. (4) Under the condition of sandy loam, with the increase of soil pH value, the number of unearthed and the number of parasitic quantities also increased firstly and then decreased, and reached the maximum when the soil pH was 8, the numbers of unearthed and the number of parasitic quantities was 47.5 and 51.1, respectively. There is a high number of parasites in the alkaline soil environment. The study found that sandy loam soil type, soil temperature 25~30 ℃, soil moisture 60%~70% and soil pH 8 is beneficial to the parasitism and growth of sunflower broomrape. Therefore, in order to reduce the harm of broomrape, sunflower should be planted in non neutral or acidic nonsandy soil plots, and attention should be paid to adjusting the sowing date and controlling the amount of irrigation in the field.

Abstract:New energy plant duckweed was used as material, we studied the effects of five different concentration of IAA at 0.001, 0.01, 0.1, 1 and 10 μmol/L (0 μmol/L as control) on the growth and starch accumulation of duckweed. The results showed that: （1）Low concentrations (0.001, 0.01 and 0.1 μmol/L) of IAA could effectively promote the chlorophyll content, net photosynthetic rate and biomass yield of duckweed, which significantly increased by 14.7%, 10.6%, and 28.1% compared with the control group at the concentration of 0.001 μmol/L IAA. （2） High concentrations (1 and 10 μmol/L) of IAA can regulate the starch accumulation and increase the activity of AGPase (ADPglucose pyrophosphorylase), a key enzyme in starch synthesis. As compared to the control, the starch content and AGPase activity were significantly increased by 35.0% and 14.1% at 10 μmol/L IAA treatment, respectively. These results suggest that low concentration of IAA treatment can effectively promote the biosynthesis of chlorophyll and photosynthesis of duckweed, which is conductive to the accumulation of biomass, and high concentration of IAA can promote the starch percentage and total starch accumulation by enhancing the activity of AGPase.

Abstract:Gynura divaricata samples were collected from 12 differently experimental fields in Shaanxi Province, and the amount of total flavonoids and B vitamins in stems and leaves were measured. The redundancy analysis (RDA) was conducted to reveal the relationship between active components and differently ecological factors, which were obtained from China Integrated Meteorological Information Service System. The results indicated that: (1)the amount of total flavonoids and B vitamins in G. divaricata from different fields showed significant differences. The total flavonoids in G. divaricata from 4 experimental fields in Luonan County were the highest, whereas the amount of B vitamins was the lowest. Besides that, the content of total flavonoids appeared significant negative correlation with the amount of B2, B₆, B₁₂ and Bvitamins in stems and leaves of G. divaricata. (2) Geographic position and environmental factors, such as elevation, precipitation and local temperature affected the accumulation of active components in G. divaricata. Interestingly, the total flavonoids could be positively determined by elevation and precipitation, but for B vitamins, it presented negative correlation with these two factors. So, it is concluded that Luonan county in the Qinba Mountain Area (alt: 800-900 m; average monthly rainfall in JulAug: 78-84 mm; average ground temperature: 26-27.5 ℃) was an optimal place for the cultivation of G. divaricata in Shaanxi Province.

Abstract:Based on field investigation, sample collection and determination of biomass in various organs, we studied the biomass distribution characteristics of reproductive twigs of Dodonaea viscosa in the dryhot valley of Jinsha River. The results showed that: (1) female plants in D. viscosa population in the dryhot valley of Jinsha River had significant advantages, and the sex ratio of male/female was 0.11, which showed a very significant deviation from the ratio of 1∶1 (P<0.001). (2) The morphological characteristics and biomass allocation traits of the twigs were genderdifferent. The flower biomass and total biomass of female reproductive twigs were significantly higher than those of male and bisexual twigs (P<0.05), but there was no significant difference for biomass distribution between male and bisexual. Gender differences have been found in reproductive distribution, but not in leaves biomass of reproductive twigs. (3) There was a significant positive correlation between reproductive biomass of twigs and flower biomass, as well as vegetative biomass and flower biomass (P<0.001), but there was no significant correlation between reproductive allocation and the size of reproductive twigs. Our results indicated that there was no tradeoff between vegetative growth and reproductive growth, and reproductive allocation was not dependent on individual size. This biomass allocation model of D. viscosa might be an adaptation to the special environment of the dryhot valley of Jinsha River.

Abstract:In this study, we took the data of the Inner Mongolia part in The Catalogue of Rare and Endangered Plants in China, The China Plant Red Book, The National Key Protected Wild Plants List (List No.1), the threatened species in The China Species Red List, the threatened species in The Red List of Chinese BiodiversityThe volume of Higher Plants (2013), The Catalogue of Rare and Endangered Plants in Inner Mongolia and Recorded Illustration of Rare and Endangered Plants in Inner Mongolia as initial data, and performed a series of revision and perfection to the name, latin name, attribution of families and genera and other problems. Eventually, we confirmed 127 rare and endangered plant species as objects of the study. During our systematic collecting and organizing of the research results and data of different scholars on relevant documents of rare and endangered plants in Inner Mongolia, we also conducted field investigation and specimen collection, the geographic distribution and features of flora of plants were analyzed in this area. Results showed that：（1） there are 127 rare and endangered plants, 103 genera and 53 families in Inner Mongolia, among which, pteridophyte covers 1 species; gymnosperm 3 families 5 genera and 9 species; angiosperm 49 families 97 genera and 117 species.（2） East and West Alashan state, Helan Mountain state and Xingan North State share more distribution of the rare and endangered plants in Inner Mongolia, each taking up to 59 species, 46.46% of the total number.（3）The vertical distribution pattern of rare and endangered plants in Inner Mongolia presents an unimodal form, with the largest amount of plant species between 1 000 and 1 600 meters. (4) Among the rare and endangered plants in Inner Mongolia, the number of Leguminosae, Compositae and Ranunculaceae species ranks top, 35 monotypic genera. (5) As for the rare and endangered plants in Inner Mongolia floristic elements, temperate distribution has the highest proportion, with ancient origin, there are many relic plants, while herb and mesophytes enjoy the largest proportion, similar to the floristic characteristics of Inner Mongolia. The aim of the research is to perform a series of revision and perfection to the list of rare and endangered plants in Inner Mongolia.

Abstract:In July 2016 and August 2017，algae samples were collected twice from TwoRiver Source Natural Reserve of Altay Mountains in Xinjiang. Through microscopic observation，we found five Chinese new record plants，which belong to 4 genera，including 4 species and 1 variety. They were Closterium tumidulum Gay，Pleurotaenium crenulatum (Ralfs) Rabenhorst，Euastrum coeselii Kouwets，Cosmarium crenulatum Ngeli，Cosmarium reniforme var. compressum Nordstedt.

Abstract:The DNA binding with one finger (Dof) protein is a kind of plant specific transcription factors, which usually has 200-400 amino acids and two main domains. The Nterminal of the Dof protein was highly conserved and could interact with DNA and protein. The Cterminal which has variable amino acid sequence is the specific transcriptional regulatory domain of Dof gene. Recently, it has been reported that Dof proteins are involved in the growth and development of different plants as transcriptional activators or repressors. Until now, with the rapid development of genome sequencing technology, a large number of Dof genes have been identified from different species. Here, the structural features, member identification in whole genome, interaction proteins, as well as the progress of biological function of Dof family members from different plants in recent years were summarized, and we hope this work would be helpful in the further study of Dof transcription factors.