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Nutrient resorption and stoichiometry ratios are vital indicators to explore nutrient transfer and use efficiency for plants, particularly under the condition of nutrient limitation. However, the changing rules about nutrient resorption and ecological stoichiometry homeostasis are still unclear with the development of plantations. We determined carbon (C), nitrogen (N), and phosphorus (P) concentrations in soil and in fresh and senesced needles along a chronosequence of Pinus massoniana plantations (10, 20, 30, and 36 years old) in Guizhou Province, China. We also calculated the N and P resorption efficiency (NRE and PRE, respectively) and the homeostasis coefficient. The results showed that fresh and senesced needles’ C and N concentrations maintained an increasing trend, whereas their P concentrations decreased initially and subsequently increased as the plantations’ ages increased. Fresh needles’ N:P ratios indicated that N limitation existed before 20 years old, while P limitation appeared in the 30-year-old plantations. The NRE and PRE showed patterns of increasing initially and decreasing subsequently along the chronosequence of P. massoniana plantations, which was coupled with weak stoichiometric homeostasis to reduce nutrient deficiency. Therefore, the appropriate nutrient management measurements should be induced to promote tree growth and the sustainable development of P. massoniana plantations.

Flower color is one of the crucial traits of ornamental plants. Rhododendron delavayi Franch. is a famous ornamental plant species distributed in the mountain areas of Southwest China. This plant has red inflorescence and young branchlets. However, the molecular basis of the color formation of R. delavayi is unclear. In this study, 184 MYB genes were identified based on the released genome of R. delavayi. These genes included 78 1R-MYB, 101 R2R3-MYB, 4 3R-MYB, and 1 4R-MYB. The MYBs were divided into 35 subgroups using phylogenetic analysis of the MYBs of Arabidopsis thaliana. The members of the same subgroup in R. delavayi had similar conserved domains and motifs, gene structures, and promoter cis-acting elements, which indicate their relatively conserved function. In addition, transcriptome based on unique molecular identifier strategy and color difference of the spotted petals, unspotted petals, spotted throat, unspotted throat, and branchlet cortex were detected. Results showed significant differences in the expression levels of R2R3-MYB genes. Weighted co-expression network analysis between transcriptome and chromatic aberration values of five types of red samples showed that the MYBs were the most important TFs involved in the color formation, of which seven were R2R3-MYB, and three were 1R-MYB. Two R2R3-MYB (DUH019226.1 and DUH019400.1) had the highest connectivity in the whole regulation network, and they were identified as hub genes for red color formation. These two MYB hub genes provide references for the study of transcriptional regulation of the red color formation of R. delavayi.

People show a separation of intention and behavior in green consumption, and promoting actual green purchase behavior is more important than purchase intention. This study adopted a conflicting environmental decision paradigm to investigate behavioral and neural processes during actual green consumption decision-making involving different types of green products and message framing, according to construal level theory. Participants were instructed to make green consumption decisions involving green products with different psychological distances (self-interested green products vs. other-interested green products) under gain (e.g., buying green products brings positive results) or loss framing (e.g., not buying green products brings negative effects) while electroencephalograms were recorded. The behavioral results demonstrated that participants tended to purchase green products under loss framing more than under gain framing. The event-related potential results showed that under gain framing, decision-making for self-interested green products was associated with larger P3 than decision-making for other-interested green products. While under loss framing, decision-making for other-interested green products has a larger P260 than for self-interested green products. These findings suggest that under gain framing, self-interested green products elicit more cognitive resources than other-interested green products, while under loss framing, other-interested green products elicit stronger negative emotions than self-interested green products. The research has managerial implications for promoting consumers’ actual purchase behavior.

Five Larix species (L. griffithii, L. speciose, L. himalaica, L. kongboensis, and L. potaninii var. australis), have survived on the Qinghai-Tibet Plateau (QTP) under specific climate conditions for decades. The lack of genomic information seriously hinders research on the evolution, conservation and ecology of these Larix resources. In this study, complete chloroplast (cp) genomes of the 5 species were assembled and compared based on next generation sequencing technology combined with polymerase chain reaction validation. The results show that the 5 cp genomes are relatively conservative in size, gene content and arrangement, and border variation. Phylogenetic analysis showed that the species are closely related as well as to seven other species of the same genus. In addition, the 5 cp genomes contained few simple sequence repeats and relatively low nucleotide variability; thus, 12 candidate polymorphic cp DNA markers will be helpful for further research on relevant population genetics. These results will provide valuable genetic information for the conservation, evolution and ecology of these species and their relatives.

Four evergreen broadleaf Rhododendron spp. (Rhododendrons), namely, Rhododendron aganniphum, R. nyingchiense, R. wardii, and R. triflorum, occur in harsh subalpine habitats in the southwest Qinghai-Tibet Plateau (QTP), China. Considering that the four Rhododendrons cannot escape their unique environment, they must evolve a set of adaptations to survive, but the information is lacking. To uncover their physiological adaptation characteristics, in the present study, we monitored their physiological characteristics by determination of their seasonal variation in antioxidant enzyme activity, osmotic adjustment substrates, and carbohydrate contents, and their pigment content and photosynthetic efficiency. The results showed that superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) activities and proline content of four Rhododendrons had a significant difference in autumn and were insignificant in summer. Specifically, R. aganniphum had the maximum protective enzyme activity and proline content in winter as well as chl a, b, and car contents. The values of maximal quantum yield (Fv/Fm), photochemical efficiency (ΦPSII), and non-photochemical quenching (NPQ) of four Rhododendrons were significantly higher in summer than in other seasons. The lower qP indicated the four Rhododendrons were susceptible to photoinhibition. Overall, the four Rhododendrons had similar physical characteristics in subalpine habitats. The parameters of the maximum quantum yield of photosystem II (PSII), the actual quantum yield of PSII, the non-photochemical chlorophyll fluorescence quenching, and chlorophyll a content increased in summer. Meanwhile, the protective enzyme activity and total soluble sugar content, proline content, and carotenoid content increased in spring, autumn, and winter. These results suggested that the four Rhododendrons can adapt to subalpine habitats by heat dissipation to avoid the damage of excessive radiation during the warm season while scavenging reactive oxygen and increasing the intracellular fluid concentration to avoid damage caused by chilling temperatures during the cold seasons. These findings would provide a reference for the conservation and application of these valuable ornamental evergreen broadleaf Rhododendrons, and enrich theory of plant eco-physiology in the high altitudes of the QTP.

Male sterility caused by stamen petalody is a key factor for a low fruit set rate and a low yield of Camellia oleifera but can serve as a useful genetic tool because it eliminates the need for artificial emasculation. However, its molecular regulation mechanism still remains unclear. In this study, transcriptome was sequenced and analyzed on two types of bud materials, stamen petalody mutants and normal materials, at six stages of stamen development based on integrated single-molecule real-time (SMRT) technology with unique molecular identifiers (UMI) and RNA-seq technology to identify the hub genes responsible for stamen petalody in C. oleifera. The results show that a large number of alternative splicing events were identified in the transcriptome. A co-expression network analysis of MADSs and all the differentially expressed genes between the mutant stamens and the normal materials showed that four MADS transcription factor genes, CoSEP3.1, CoAGL6, CoSEP3.2, and CoAP3, were predicted to be the hub genes responsible for stamen petalody. Among these four, the expression patterns of CoAGL6 and CoSEP3.2 were consistently high in the mutant samples, but relatively low in the normal samples at six stages, while the patterns of CoSEP3.1 and CoAP3 were initially low in mutants and then were upregulated during development but remained relatively high in the normal materials. Furthermore, the genes with high connectivity to the hub genes showed significantly different expression patterns between the mutant stamens and the normal materials at different stages. qRT-PCR results showed a similar expression pattern of the hub genes in the RNA-seq. These results lay a solid foundation for the directive breeding of C. oleifera varieties and provide references for the genetic breeding of ornamental Camellia varieties.

Perceptual cues act as signals in the aesthetic value environment, which promote emotion regulation toward pro-environment behavior. This type of perception-emotion-behavior reactivity forms the core of human altruism. However, differences in pro-environmental behavior may result from variation across high-aesthetic-value (HAV) and low-aesthetic-value (LAV) environments. This study investigated the neural mechanisms underlying interaction effects between environmental context and emotion regulation on pro-environmental behavior by integrating behavioral and temporal dynamics of decision-making information processing with event-related potential (ERP) technique measures. The results indicated that changing anticipated emotions changes pro-environmental behavior. Regarding changing aesthetic value environments, while modulating emotion regulation, significant differences were found in brain regions and mean amplitudes of N1, P2, N2, and late positive potential (LPP) components, which anticipated emotion. The findings suggest that environmental aesthetic value and emotion regulation impact pro-environmental behavior.

Sophora moorcroftiana, an endemic Fabaceae species occurred in the Qinghai-Tibet plateau, China, has important economic value in local. Its completed plastome sequence is 148,930 bp in size, and comprises a pair of inverted repeat (IR) regions of 23,787 bp each, a large single-copy region of 83,342 bp and a small single-copy region of 18,014 bp. The GC content of the plastome was 30.2%. A total of 124 genes were identified, comprising 80 protein-coding genes, 36 tRNA genes and eight rRNA genes. There are 94 unique genes, with 15 genes duplicated in the IR regions. Phylogenetic tree shows that plastome of S. moorcroftiana is most related to that of S. alopecuroides. This plastome would be helpful for the study of molecular mechanism of photosynthesis, sustainable conservation, genetic improvement of S. moorcroftiana.

Background Rhododendron delavayi Franch. var. delavayi is a wild ornamental plant species in Guizhou Province, China. The lack of its plastid genome information seriously hinders the further application and conservation of the valuable resource. Methods The complete plastid genome of R. delavayi was assembled from long sequence reads. The genome was then characterized, and compared with those of other photosynthetic Ericaceae species. Results The plastid genome of R. delavayi has a typical quadripartite structure, and a length of 202,169 bp. It contains a large number of repeat sequences and shows preference for codon usage. The comparative analysis revealed the irregular recombination of gene sets, including rearrangement and inversion, in the large single copy region. The extreme expansion of the inverted repeat region shortened the small single copy, and expanded the full length of the genome. In addition, consistent with traditional taxonomy, R. delavayi with nine other species of the same family were clustered into Ericaceae based on the homologous protein-coding sequences of the plastid genomes. Thus, the long-read assembly of the plastid genome of R. delavayi would provide basic information for the further study of the evolution, genetic diversity, and conservation of R. delavayi and its relatives.

Sophora moorcroftiana (Benth.) Baker is an endemic woody species distributed in the Qinghai–Tibet Plateau (QTP), a part of the world characterized by high altitude and cold weather. In this study, the genetic diversity of S. moorcroftiana was evaluated based on 300 representative samples of 15 populations using 20 polymorphic SSR markers, and its potential distribution was predicted according to 19 bioclimatic factors using MaxEnt modeling. Results showed the population genetic diversity of S. moorcroftiana was generally not high (around 0.5), and the range of variation was small (0.437–0.539). Altitude, rather than other environmental factors, was the key factor affecting the present genetic diversity. Moreover, due to climate change in the QTP, the suitable area is increasing and will continue to increase by 48.35%, 84.44%, 101.98%, and 107.30% in the four future periods of 2030s, 2050s, 2070s, and 2090s, respectively, compared to the present, which is beneficial for S. moorcroftiana. These results will provide a theoretical basis for the development of germplasm conservation strategies for S. moorcroftiana and enrich information on the impacts of climate change on plants in the QTP.

The two tree peony species, namely, Paeonia ludlowii (Stern & G. Taylor) D. Y. Hong and P. delavayi Franch, belongs to the section Moutan Paeonia (Paeoniaceae). They are the only sources of yellow pigment in tree peony cultivar breeding. P. ludlowii has been listed as “critically endangered”, whereas P. delavayi has been listed as “near threatened” species according to the China Species Red List. The complete chloroplast genome sizes of P. ludlowii and P. delavayi are 152,687 and 154,405 bp respectively. Both contain a 17,056 bp long small single copy region (SSC). The large single copy region (LSC) in P. ludlowii is 84,613 bp, whereas the inverted repeat regions (IRs) are 25,644 bp. In addition, LSC in P. delavayi is 86,142 bp, whereas the IRs is 25,650 bp. The genomes of the two species encode the same set of 134 genes, including 86 protein-coding genes, 8 ribosomal RNA genes and 40 transfer RNA genes. Phylogenetic analysis revealed that all five Paeonia species clustered together, and P. ludlowii and P. delavayi are most closely related to each other. These newly characterized chloroplast genomes will provide essential data for the further conservation of P. ludlowii and P. delavayi.

It has been shown that the oxidized low density lipoprotein receptor 1 (OLR1) gene plays an important role in the degradation of oxidized low density lipoprotein. Previous studies found a SNP in the 3'-untranslated region (3'-UTR) of the OLR1 gene associated with milk production traits in different dairy cattle populations and with loin eye area and marbling depth in beef cattle. MicroRNAs can regulate gene expression by binding the 3'-UTR of target genes to degrade or to repress the translation of target genes. Bioinformatics have shown that there is a binding site of bta-miR-370 in the 3'-UTR of the OLR1 gene, and a previous luciferase reporter assay system showed that the A/C mutation occurring in the 3'-UTR of this gene caused the binding sites of bta-miR-370 to disappear in HEK293 cells. To further validate whether OLR1 was the target gene of bta-miR-370, the over-expression and interference expression of bta-miR-370 were determined by transfecting bta-miR-370 mimics and inhibitor supplementations into bovine adipocyte. The qRT-PCR result showed that the relative expression of OLR1 gene significantly decreased in the mimics group compared to the control, whereas the expression level in inhibitor group was higher than its control group. The above results were further verified by a Western blot at the protein level. In addition, lipid formation analysis of bovine adipocytes was performed via oil red O staining, and we found that cytoplasm lipid droplets in the inhibitor group showed a tendency to increase compared to the control group, whereas in the mimics group, we observed an obvious decrease of cytoplasm lipid droplets compared to the control and inhibitor groups. Taken together, our data here suggest that bta-miR-370 has a negative regulation role for OLR1 both at the gene expression and protein levels and bovine adipocytes cytoplasm lipid droplets formation, which provides a reference for illustrating how the OLR1 gene affects milk production and beef quality traits in cattle.

Cupressus gigantea and C. torulosa are ecologically and economically important endemic species of the conifer family Cupressaceae on the Qinghai-Tibetan plateau. C. gigantea was previously classified as a subspecies of C. torulosa because of their similar morphological characteristics and close distribution. In this study, 401 individuals were sampled from 16 populations of the two Cupressus species. The specimens were genotyped using 10 polymorphic microsatellite loci through fluorescence polymerase chain reaction (PCR). The genetic diversity of C. gigantea and C. torulosa populations was generally low, with the highest genetic diversity detected in the population LLS of C. gigantea. Distance-based phylogenetic and principal co-ordinates analyses indicated a clear genetic structures for the 16 populations of the two Cupressus species. Moreover, Mantel test results showed indistinctive correlations between population-pairwise Fst values and geographic distances, as well as between genetic distances and geographic distances in C. gigantea and C. torulosa, respectively. AMOVA suggested that genetic variation mostly resided within populations. Sixteen naturalpopulations were evidently clustered into two major groups in the constructed neighbour-joining tree. The results demonstrated that C. gigantea and C. torulosa are different Cupressus species. The genetic information provided important theoretical references for conservation and management of the two endangered Cupressus species.

Sophora moorcroftiana, an endemic Fabaceae species occurred in the Qinghai-Tibet plateau, China, has important economic value in local. Its completed plastome sequence is 148,930 bp in size, and co...

Tibetan hulless barley (Hordeumvulgare subsp. vulgare) is exposed to harsh environmental factors, such as drought, salinity, and cold. To explore useful transcription factor genes that could improve stress resistance of Tibetan hulless barley varieties, five WRKY genes were isolated from drought tolerance Tibetan hulless barley genotype TR1, namely, HvvWRKY2, HvvWRKY5, HvvWRKY10, HvvWRKY19, and HvvWRKY46. The HvvWRKY46 belongs to Group I of the WRKY superfamily, whereas the remaining four belong to Group II. All of them were localized to the nucleus of onion epidermal cells. The respective expression of the five WRKY genes was compared under drought, salt, and cold stress in resistant genotype TR1 and sensitive genotype TS1. Among the five, HvvWRKY2, HvvWRKY5, HvvWRKY19, and HvvWRKY46 were induced by drought or PEG6000 stress in TR1 but not in TS1, suggesting that these four WRKY genes are involved in drought resistance. HvvWRKY2 was induced by salt stress in TR1 but not in TS1, indicating that HvvWRKY2 may be involved in salt resistance. What’s more, HvvWRKY2 were notably up-regulated in TR1 under cold stress, whereas it was only induced at low level in TS1, indicating that HvvWRKY2 may also participate in cold tolerance.

Various plant species in the Qinghai-Tibet Plateau exposed to harsh conditions, such as low oxygen, drought, extremely low temperatures and salinity, have evolved both molecular and physiological adaptation strategies to deal with these multiple stresses. Sophora moorcroftiana (Benth.) Baker (Fabaceae) is a highly drought-resistant endemic Sophora shrub species in the Qinghai-Tibet Plateau. In our previous study, a drought-induced DREB transcription factor gene was identified and was designated as SmDREB1. SmDREB1-GFP fusion construct was introduced into Arabidopsis protoplast to characterise the function of SmDREB1 in drought resistance. The results showed that SmDREB1 targets the nucleus of Arabidopsis protoplast. Ectopic expression of SmDREB1 in model plant species Arabidopsis was performed. The transgenic lines showed increasing expressions of drought marker genes including AtDHN, AtLEA, AtPIP2 ;2, AtPIP2;3 and AtRD29, increasing activities of antioxidant enzymes and proline contents and increasing light-use efficiency under drought stress as compared with the wild-type plants; SmDREB1 transgenic lines are more resistant to drought than wild-type plants. Therefore, the SmDREB1 is a drought-resistant transcription factor gene of S. moorcroftiana and could be a candidate in genetic engineering to improve drought resistance of plateau plant species.

RING finger proteins comprise a large family and play important roles in regulation of growth and development, hormone signalling, and responses to biotic and abiotic stresses in plants. In this study, the identification and functional characterization of a C4C4-type RING finger protein gene from the Chinese wild grapevine Vitis pseudoreticulata (designated VpRFP1) are reported. VpRFP1 was initially identified as an expressed sequence tag (EST) from a cDNA library constructed from leaves of V. pseudoreticulata inoculated with the grapevine powdery mildew Uncinula necator. Sequence analysis of the deduced VpRFP1 protein based on the full-length cDNA revealed an N-terminal nuclear localization signal (NLS) and a C-terminal C4C4-type RING finger motif with the consensus sequence Cys-X(2)-Cys-X(13)-Cys-X(1)-Cys-X(4)-Cys-X(2)-Cys-X(10)-Cys-X(2)-Cys. Upon inoculation with U. necator, expression of VpRFP1 was rapidly induced to higher levels in mildew-resistant V. pseudoreticulata plants. In contrast, expression of VpRFP1 was down-regulated in mildew-susceptible V. vinifera plants. Western blotting using an antibody raised against VpRFP1 showed that VpRFP1 was also induced to higher levels in V. pseudoreticulata plants at 12-48 hours post-inoculation (hpi). However, there was only slight increase in VpRFP in V. vinifera plants in the same time frame, even though a more significant increase was observed at 96-144 hpi in these plants. Results from transactivation assays in yeast showed that the RING finger motif of VpRFP1 exhibited some activity of transcriptional activation; however, no activity was seen with the full-length VpRFP1. Overexpression of VpRFP1 in Arabidopsis plants was found to enhance resistance to Arabidopsis powdery mildew Golovinomyces cichoracearum, which seemed to be correlated with increased transcript levels of AtPR1 and AtPR2 in the pathogen-infected tissues. In addition, the Arabidopsis transgenic lines showed enhanced resistance to a virulent bacterial pathogen Pseudomonas syringae pv. tomato DC3000. Taken together, the results suggested that VpRFP1 may be a transcriptional activator of defence-related genes in grapevines.

According to the conservative regions of the nucleotide-binding site and leucine-rich repeat domain (NBS–LRR) in resistance genes (R-gene), a homology-based cloning method was used to isolate disease resistance gene candidates (RGCs) from six species of pear, including Pyrus betulaefolia, P. bretschneideri, P. pyrifolia, P. ussriensis, P. sinkiangensis, P. communis and their interspecific hybrids. Approximately 100 disease resistance gene candidates from 39 cultivars in these pear species were identified. Among these RGC, 98 of genomic sequences which could be translated into polypeptides without stop codons, while the other two sequences presented multiple stop codons. The deduced amino acid sequences of the 98 RGC displayed high diversity, ranging from 20 to 100%, and could be divided into 17 distinct RGC families (RGC 1–RGC 17) based on the phylogenetic analysis with the threshold of 68% identity. The 98 RGC contained both the toll interleukin receptor (TIR) group and non-toll interleukin receptor (non-TIR) group. RGC families RGC 16 and RGC 17 belonged to non-TIR group, the other 15 RGC families were classified to TIR group. Sequences analysis indicated that there was a strong identity of these RGCs to the known R-gene and RGC from other plants. In each RGC family, one representative RGC was selected to test the expression profile at transcriptional level, and all the 17 selected RGCs could be detected at mRNA level. In response to Venturia nashicola inoculation or salicylic acid (SA) treatment, the expression level of RGC Pb-Zs1 (RGC 1) from pear scab-resistant cultivar ‘Zaosu’ pear changed while the expression level of RGC Pb-Dshs2 (RGC 8) from pear scab-susceptible pear cultivar ‘Dangshansu’ seemed less affected. These RGCs isolated in this study could help understand the R-gene in pear species and will serve as a potential resource for future improvement of disease resistance in pear.

In this study, two WRKY genes were isolated from Erysiphe necator-resistant Chinese wild Vitis pseudoreticulata W. T. Wang 'Baihe-35-1', and designated as VpWRKY1 (GenBank accession no. GQ884198) and VpWRKY2 (GenBank accession no. GU565706). Nuclear localization of the two proteins was demonstrated in onion epidermal cells, while trans-activation function was confirmed in the leaves of 'Baihe-35-1'. Expression of VpWRKY1 and VpWRKY2 was induced rapidly by salicylic acid treatment in 'Baihe-35-1'. Expression of VpWRKY1 and VpWRKY2 was also induced rapidly by E. necator infection in 11 grapevine genotypes; the maximum induction of VpWRKY1 was greater in E. necator-resistant grapevine genotypes than in susceptible ones post E. necator inoculation. Furthermore, ectopic expression of VpWRKY1 or VpWRKY2 in Arabidopsis enhanced resistance to powdery mildew Erysiphe cichoracearum, and enhanced salt tolerance of transgenic plants. VpWRKY2 also enhanced cold tolerance of transgenic plants. In addition, the two proteins were shown to regulate the expression of some defense marker genes in Arabidopsis and grapevine. The data suggest that VpWRKY1 and VpWRKY2 may underlie the resistance in transgenic grapevine to E. necator and tolerance to salt and cold stresses.

Choice of native woody species with higher drought tolerance is the basic work on afforestation in Qinghai–Tibet Plateau (QTP) region. However, no systemic evaluation has been made of the drought tolerance ability. In the present study, we compared the drought injury degree and ten physiological and biochemical indices from six native deciduous and broad-leaved woody plant species seedlings under continuous drought for 21 days. The ten indices included relative water content, net photosynthetic rate, transpiration, water use efficiency, superoxide dismutase, peroxidase, catalase and malondialdehyde, proline and soluble sugars contents of leaves. Under drought stress, six native species showed the different response. According to analysis of the mean membership function values, the drought tolerance of six native species could be ranked in the following order: Berberis hemsleyana > Sophora viciifolia > Betula platyphylla > Cotoneaster rotundifolius > Prunus mira > Hippophae rhamnoides. Species B. hemsleyana and S. viciifolia were relatively high drought-tolerant, while P. mira and H. rhamnoides were relatively low tolerant. The two high-tolerant native species resist to drought by different strategies after long-term adaptation, and these two species should be given prior consideration in deciduous woody plant species selection for afforestation in arid and semi-arid area of QTP in the future.

The complete chloroplast (cp) genome of the Sinopodophyllum hexandrum (Berberidaceae) was determined in this study. The circular genome is 157,940 bp in size, and comprises a pair of inverted repeat (IR) regions of 26,077 bp each, a large single-copy (LSC) region of 86,460 bp and a small single-copy (SSC) region of 19,326 bp. The GC content of the whole cp genome was 38.5%. A total of 133 genes were identified, including 88 protein-coding genes, 37 tRNA genes and eight rRNA genes. The whole cp genome consists of 114 unique genes, and 19 genes are duplicated in the IR regions. The phylogenetic analysis revealed that S. hexandrum is closely related to Nandina domestica within the family Berberidaceae.

The complete chloroplast genome of the wild Cupressus gigantea (Cupressaceae) is determined in this study. The circular genome is 128 244 bp in length with 115 single copy genes and two duplicated genes (trnI-CAU and trnQ-UUG). This genome contains 82 protein-coding genes, four ribosomal RNA genes and 31 transfer RNA genes. In these genes, eight genes (atpF, rpoC1, ndhA, ndhB, petB, petD, rpl16 and rpl2) harbor a single intron and two genes (rps12 and ycf3) harbor two introns. This genome does not contain canonical IRs, and the overall GC content is 34.7%. A maximum parsimony phylogenetic analysis revealed that C. gigantea and C. sempervirens are more closely related.

Ethylene response factor (ERF) functions as an important plant-specific transcription factor in regulating biotic and abiotic stress response through interaction with various stress pathways. We previously obtained three ERF members, VpERF1, VpERF2, and VpERF3 from a highly powdery mildew (PM)-resistant Chinese wild Vitis pseudoreticulata cDNA full-length library. To explore their functions associated with plant disease resistance or biotic stress, we report here to characterize three ERF members from this library. PM-inoculation analysis on three different resistant grapevine genotypes revealed that three VpERFs displayed significant responses, but a different expression pattern. Over-expression of VpERF1, VpERF2, and VpERF3 in transgenic tobacco plants demonstrated that VpERF2 and VpERF3 enhanced resistance to both bacterial pathogen Ralstonia solanacearum and fungal pathogen Phytophtora parasitica var. nicotianae Tucker. Importantly, VpERF1-overexpressing transgenic Arabidopsis plants increased susceptibility toward these pathogens. Investigation on drought, cold, and heat treatments suggested, VpERF2 was distinctly induced, whereas VpERF3 displayed a very weak response and VpERF1 was distinctly induced by drought and heat. Concurrently, VpERF3 was significantly induced by salicylic acid (SA), methyl jasmonate (MeJA), and ET. Our results showed that the three VpERFs from Chinese wild V. pseudoreticulata play different roles in either preventing disease progression via regulating the expression of relevant defense genes, or directly involving abiotic stress responsive pathways.

In this study, a novel bZIP-like gene was isolated from Chinese wild Vitis pseudoreticulata W. T. acc. Baihe-35-1. The full-length complementary deoxyribonucleic acid (cDNA) sequence of the gene was 1583 bp including 159 bp 5’ untranslated region (UTR), 365 bp 3’ UTR and a 1083 bp ORF which encodes a polypeptide of 360 amino acids with a molecular weight of 38.662 kDa. The deduced amino acid sequence shares an overall 46 to 69.8% sequence similarity with bZIP from other plants. Therefore, we designated this gene as V. pseudoreticulata bZIP ( VpbZIP-like ). The expression of VpbZIP -like was induced 12 h post inoculation (hpi) by Erysiphe necator, but transiently decreased, then increased in these two genotypes and its expression was lower in highly resistant genotype Baihe-35-1 than in susceptible genotype Hunan-1 at 24, 48 and 72 hpi. We further tested whether the expression was also a response to plant signaling molecules. Results indicate that the susceptible genotype Hunan-1 showed higher expression of VpbZIP-like than the highly resistant genotype Baihe-35-1 after exogenous application of methyl jasmonate (MeJA), salicylic acid (SA) and ethephon (Eth). Moreover, tissue specific expression pattern of VpbZIP -like was analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Results reveal that it was in lower lever in flower than in leaf, stem, tendril and fruit. The CDS of VpbZIP -like was inserted into the prokaryotic expression construct pGEX-4T-1, and then transformed into Escherichia coli BL21-code induced by isopropyl-b-D-thiogalactopyranoside (IPTG) which resulted in the production of a Mr. 64 kDa of GST- VpbZIP -like fusion protein displayed in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Key words : Chinese wild Vitis, bZIP, gene expression, signaling molecules, fusion protein expression.