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In vitro flowering and fruiting of Portulaca pilosa L. were achieved for the first time. The ability of several factors to induce in vitro flowering, including plant growth regulators and carbon sources, were investigated. Initial in vitro flowering (12.1%) from stems, most likely from floral buds that had differentiated before stem sections were inoculated on MS medium supplemented with 30 g/L sucrose, 1.0 µM BA and 0.1 µM NAA, occurred within less than one month. Axillary shoots were subcultured multiple times on this medium. Secondary in vitro flowering (12.2%) and fruit setting from axillary shoots was possible on MS medium supplemented with 120 g/L sucrose without any plant growth regulators. Continuous culture on this medium for 12 days after flowering yielded fruits and produced a mean 58 normal seeds per fruit. Seeds germinated and developed seedlings in vitro without any additional treatment.

Scaevola sericea (Gaertn.) Roxb., which is a semi-mangrove halophyte, displays low seed germination (SG) and poor development. A model system was established to assess seed viability (SV) and enhanced SG in response to 2,3,5-triphenyl-tetrazolium chloride (TTC), and to detect SV under different storage conditions and duration to establish an optional storage method for seeds. Percentage SG (SG%) was also tested with different periods of soaking in water, gibberellic acid (GA3) and seawater after removing fruit pulp. Optimal detection of the percentage of SV (SV%) was possible when seeds were soaked for 3 h in 0.4% TTC. In these conditions, after 15 d, SV% exceeded 90.0%. This indicates that low SG was not related to SV under natural conditions. The nutritious epicarp (pulp) of intact fruit is easily infected by mildew, rotting rapidly in high relative humidity (60–90%). When pulp was removed from fruits, germination period was speeded up by almost 8 d (seeds germinated after sowing for 28 d). This also increased SG%. Seawater broke seed dormancy more efficiently than GA3. The SG% (59.0%) of seeds with their epicarp removed then soaked in seawater for 24 h was higher than seeds soaked in distilled water (24.0%) or in 200 mg/L GA3 (33.7%) after sowing for 40 d The SV% of seeds stored at 4 °C was higher than seeds stored at room temperature (25±3 °C), but when storage period was extended to 180 d or longer, their SV% declined rapidly. In natural conditions, S. taccada seeds have a high SV%. The low SG% is caused by easily rotting pulp and the physiological dormancy of fruits. By removing the pulp and soaking naked seeds in seawater can break seed dormancy and achieve ideal SG which would benefit ecorestoration and landscaping projects.

High-purity CaCO3 via a facile two-step dissolution–carbonation coprecipitation procedure using NH4Cl, NH4OH, and CO2 with phosphogypsum (PG) as the raw material was successfully produced in the pr...

This study established, for the first time, shoot proliferation and plant regeneration protocols via shoot organogenesis from leaf explants of a medical and ornamental plant, Portulaca pilosa L. The optimal proliferation of axillary shoots was 6.2-fold within 30 days on Murashige and Skoog (MS) medium supplemented with 3.0 µM 6-benzyladenine (BA). Shoots could be induced directly from leaf explants, forming an average of 3.8 adventitious shoots per explant, on optimal MS medium supplemented with 1.0 µM thidiazuron (TDZ) and 0.1 µM α-naphthaleneacetic acid (NAA). A higher concentration of TDZ (3.0 µM), alone or in combination with 0.1 µM NAA, induced somatic embryo-like shoot buds and then developed into real shoots. Rooting was easier since roots were induced on all rooting media within one month. Half-strength MS medium free of plant growth regulators was best for rooting. Rooted plantlets were transferred to a sand: perlite (1:1, v/v) substrate, resulting in highest survival (90%). Plantlets showed more robust growth, however, on substrates of yellow mud: perlite (1:1, v/v) or peat soil: vermiculite: perlite (1:1:1, v/v).

The commercial value of Santalum album L. lies in its aromatic heartwood and essential oil. Sesquiterpenes are the main components of sandal essential oil, and these are synthesized through the plant's mevalonate (MVA) and methylerythritol phosphate (MEP) pathways. In this study, the first key rate-limiting enzyme, 1-deoxy-d-xylulose-5-phosphate synthase (SaDXS), was investigated to provide a theoretical molecular basis for the sandalwood MEP sesquiterpene biosynthetic pathway. The biofunctions of SaDXS were also analyzed. SaDXS promoters were successfully cloned from a seven-year-old S. album tree. SaDXS1A/1B promoter activity was verified by a β-glucuronidase (GUS) assay and by analyzing cis-acting elements of the promoters, which carried light- and methyl jasmonate (MeJA)-responsive signals. In an experiment involving yellow S. album seedlings, exposure to light upregulated SaDXS1A/1B expression and increased chlorophyll and carotenoid contents when overexpressed in Arabidopsis thaliana. Analysis of the expression of SaDXS1A/1B and SaSSy, key genes of santalol biosynthesis, revealed SaDXS1A expression in all tissues whereas SaDXS1B was expressed in tissues that contained photosynthetic pigments, such as stems, leaves and flowers. Sandal seedlings exogenously treated with two hormones, MeJA and ethylene, revealed similar expression patterns for SaDXS1A/1B and SaSSy. Sandal seedlings were treated with an inhibitor of DXS, clomazone, but showed no significant changes in the contents of α-santalene, β-santalene and α-santalol between treatment and control groups. These results suggest that SaDXS1A/1B play a role in the synthesis of sandalwood sesquiterpenes, providing carbon for downstream secondary metabolites. SaDXS1A/1B also play a role in the biosynthesis of chlorophyll, carotenoids, and primary metabolites.

Background Paphiopedilum, commonly known as slipper orchid, is an important genus of orchid family with prominent horticultural value. Compared with conventional methods such as tillers and in vitro shoots multiplication, induction and regeneration of protocorm-like bodies (PLBs) is an effective micropropagation method in Paphiopedilum. The PLB initiation efficiency varies among species, hybrids and varieties, which leads to only a few Paphiopedilum species can be large-scale propagated through PLBs. So far, little is known about the mechanisms behind the initiation and maintenance of PLB in Paphiopedilum. Results A protocol to induce PLB development from seed-derived protocorms of Paphiopedilum SCBG Huihuang90 (P. SCBG Prince × P. SCBG Miracle) was established. The morphological characterization of four key PLB developmental stages showed that significant polarity and cell size gradients were observed within each PLB. The endogenous hormone level was evaluated. The increase in the levels of indoleacetic acid (IAA) and jasmonic acid (JA) accompanying the PLBs differentiation, suggesting auxin and JA levels were correlated with PLB development. Gibberellic acid (GA) decreased to a very low level, indicated that GA inactivation may be necessary for shoot apical meristem (SAM) development. Comparative transcriptomic profiles of four different developmental stages of P. SCBG Huihuang90 PLBs explore key genes involved in PLB development. The numbers of differentially expressed genes (DEGs) in three pairwise comparisons (A vs B, B vs C, C vs D) were 1455, 349, and 3529, respectively. KEGG enrichment analysis revealed that DEGs were implicated in secondary metabolite metabolism and photosynthesis. DEGs related to hormone metabolism and signaling, somatic embryogenesis, shoot development and photosynthesis were discussed in detail. Conclusion This study is the first report on PLB development in Paphiopedilum using transcriptome sequencing, which provides useful information to understand the mechanisms of PLB development.

Lepturus repens (G. Forst.) R. Br. is a perennial grass that grows on coral reef outcrops and sandy beaches and has drought tolerance and salt resistance. In this study, the internodes of L. repens were used as explants and cultured on Murashige and Skoog (MS) medium supplemented with 1.13 mg L−1 6-benzyladenine (BA) to successfully induce axillary shoots. Additional experimental results showed that cytokinins were a key factor for the successful induction and proliferation of shoots. BA induced 7.2 axillary shoots per explant, significantly more than kinetin (KIN), which induced 3.5 axillary shoots per explant. Shoots were proliferated more successfully on medium supplemented with 1.13 mg L−1 BA and a low concentration of 0.09 mg L−1 1-naphthaleneacetic acid (NAA) than BA alone. Shoot bases were used as explants for embryogenic callus induction and subsequent plant regeneration, which was possible on MS medium supplemented with 0.11 mg L−1 2,4-D, 0.09 mg L−1 NAA, and 0.22 mg L−1 TDZ. Separately, callus differentiated into adventitious shoot buds on MS medium containing 1.13 mg L−1 BA or 1.10 mg L−1 KIN singly or combined with 0.09 mg L−1 NAA. On MS medium without plant growth regulators (PGR-free) or only containing 0.09 mg L−1 NAA, callus induced both adventitious shoots and somatic embryos that developed a radical on PGR-free medium. All shoots formed roots on ½MS medium containing a low concentration (0.19 to 0.37 mg L−1) of NAA or IBA within 20 d. The survival percentage of plantlets with 3 to 4 shoot clusters exceeded 99% on a substrate consisting of yellow mud, organic fertilizer, and perlite (10:3:1, v:v:v). After transplanting, plantlets with one or two shoot clusters showed 68 to 86% survival within 1 mo.

To investigate the mechanisms underlying salt tolerance, physiological parameters of six halophyte species [Vitex rotundifolia L., Clerodendrum inerme (L.) Gaertn, Phyla nodiflora (L.) Greene, Scaevola sericea Vahl, Alternanthera bettzickiana (Regel) Nichols, and Dracaena cambodiana Pierre ex Gagn] under NaCl stress in in vitro and in vivo culture tests were examined. Membership function analysis and cluster analysis divided the six species, based on their salt tolerance level, into three groups: Group 1 (highly salt tolerant) included C. inerme, A. bettzickiana and S. sericea; Group 2 (moderately salt tolerant) included P. nodiflora; Group 3 (weakly salt tolerant) included V. rotundifolia and D. cambodiana. In response to in vitro NaCl stress, all six species showed a significant increase in the activities of antioxidant enzymes. NaCl stress enhanced free proline content in the leaves of all six species. CAT, SOD activity and proline accumulation were significantly correlated with the growth of C. inerme, P. nodiflora and A. bettzickiana under in vitro NaCl treatment. We conclude that NaCl-tolerant plants may suffer slight damage within a certain salt concentration, as evidenced by the activities of antioxidant enzymes and the accumulation of free proline. Six halophytic species showed a different salt tolerance level under in vitro and in vivo culture tests, due to the activities of antioxidant enzymes and the accumulation of free proline.

Nano-carbon spheres with a controllable particle size were prepared by a hydrothermal method, and ZnO nanomaterials with three-dimensional honeycomb structures were successfully fabricated by a liquid-phase coating method using the carbon spheres as the template. The structural and morphological characterizations show that the honeycomb size and pore structure of the honeycomb-structured ZnO nanomaterials can be achieved by adjusting the hydrothermal temperature for preparing carbon spheres and the molar ratio of carbon sphere to zinc acetate. The synthesized ZnO samples exhibit high specific surface area and more surface-active sites. The degradation rate of methylene blue by the honeycomb-structured ZnO nanomaterials with a honeycomb size of 80 nm and a pore wall thickness of 10 nm reaches 95% within 90 min, which exhibits an enhancement of 108% compared with that observed for conventional micron-sized ZnO. It reveals that the structure of honeycomb-like ZnO nanomaterials can be fabricated controllably, further enhancing their surface adsorption capacity and photocatalytic reactivity.

Metasequoia glyptostroboides Hu et Cheng (dawn redwood), a known relict living fossil, is listed as a Class I rare and endangered tree in China. An efficient in vitro propagation protocol was established in this study to overcome the shortage of germplasm that cannot be compensated by conventional reproduction and as a way to preserve this tree. This objective was achieved by testing the effect of plant growth regulators (PGRs) on shoot propagation and root formation. Axillary shoots, which could be induced on PGR-free woody plant medium (WPM), were efficiently propagated on WPM supplemented with 16.0 µM zeatin and 2.5 µM indole-3-butyric acid. Improved rooting was possible on WPM supplemented with 0.05 µM α-naphthaleneacetic acid. Rooting was possible both in vitro in vermiculite-based PGR-free liquid culture and ex vitro in plastic bags containing perlite: vermiculite (1:1, v/v). This effective in vitro micropropagation protocol for M. glyptostroboides serves as a way to conserve this tree and provides an opportunity for mass production to alleviate strain on natural populations.

Nickel oxalate micro-spheres with core-shell structure of solid core and radiate shell were synthesized by precipitation method in a mixed water solution, with oxalic acid and nickel acetate as raw materials, through dropping ammonium hydroxide to adjust the solution pH value to about 8.0. Nickel microspheres with core-shell structure of solid core and porous shell were prepared by decomposing of nickel oxalate microspheres precursor at about 340 °C in argon atmosphere. The analyses of infrared spectroscopy (IR) indicates that the composition of the powders is nickel oxalate. The analyses of atomic absorption spectrometry (AAS) and organic elemental analysis (OEA) indicate that the molar ratio of (C2O4)2−/Ni2+ is about 1.02, close to the theoretical value of 1.0. The results of the thermo-gravimetric and differential thermal gravity analyses (TG-DTG) indicate that the molar ratio of (C2O4)2−/Ni2+ is about 1.06, also close to the theoretical value of 1.0. The analysis of X-ray diffraction (XRD) indicates that the composition of black powders as-prepared is nickel, which has a face-centered cubic crystal structure with average crystal grain size about 16.87 nm. The images of scanning electron microscopy (SEM) indicate that the morphology of nickel oxalate microspheres is a core-shell structure with solid core and radiate shell. The diameter of nickel oxalate microspheres is about 3 μm, and the shell consists of a large number of thin nanorods. The images of SEM also indicate that the morphology of nickel microspheres is a core-shell structure with solid core and porous shell. The diameter of nickel microspheres is about 2 μm, and the shell consists of a large number of nickel grains, surface holes and through holes. The diameter of nickel grains is about 50–100 nm, and the diameter of holes is about 50–200 nm.

Paphiopedilum spicerianum (P. spicerianum) is a rare orchid species with high ornamental value. Asymbiotic germination is the most efficient propagation method for conservation and commercial purposes because clonal propagation is very difficult and the separation of native species of Paphiopedilum through aseptic seeding is uncommon owing to their conservatism. However, a high protocorm developmental arresting rate during the asymbiotic germination is the major obstacle for seedling establishment. The fundamental understanding of embryo and protocorm developmental mechanisms will guide the development of an effective propagation method. The morphological and physiological characterization of the key developmental process of embryos and protocorms shows that the mature seeds of P. spicerianum consist of a spherical embryo without an endosperm. Seed coats become heavily lignified once the embryo is mature. Embryo cell size is relatively uniform, and significant structure polarity and cell size gradients occur at the early protocorm stage. The high level of auxin and cytokinin accumulation at the early stage of embryo development and protocorm stage may help to facilitate cell division. The transcriptome profiles of protocorms at three different developmental stages were compared to explore the regulatory mechanism of protocorm development. Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that differentially expressed genes were implicated in secondary metabolite metabolism, plant hormone signal transduction and photosynthesis. The temporal expression patterns of candidate genes related to embryo and shoot development were analyzed to reveal their roles in protocorm development: in the early stage of protocorm development, embryonic development related genes such as SERKs and BBM1 were active, while in the late stage of protocorm, shoot apical meristem related genes such as WOX8, CLAVATA2, CUC2, and SCR were active.

Sandalwood (Santalum album L.) heartwood-derived essential oil contains a high content of sesquiterpenoids that are economically highly valued and widely used in the fragrance industry. Sesquiterpenoids are biosynthesized via the mevalonate acid and methylerythritol phosphate (MEP) pathways, which are also the sources of precursors for photosynthetic pigments. 1-deoxy-D-xylulose-5-phosphate reductoisomerase (DXR) is a secondary rate-limiting enzyme in the MEP pathway. In this paper, the 1416-bp open reading frame of SaDXR and its 897-bp promoter region, which contains putative conserved cis-elements involved in stress responsiveness (HSE and TC-rich repeats), hormone signaling (abscisic acid, gibberellin and salicylic acid) and light responsiveness, were cloned from 7-year-old S. album trees. A bioinformatics analysis suggested that SaDXR encodes a functional and conserved DXR protein. SaDXR was widely expressed in multiple tissues, including roots, twigs, stem sapwood, leaves, flowers, fruit and stem heartwood, displaying significantly higher levels in tissues with photosynthetic pigments, like twigs, leaves and flowers. SaDXR mRNA expression increased in etiolated seedlings exposed to light, and the content of chlorophylls and carotenoids was enhanced in all 35S::SaDXR transgenic Arabidopsis thaliana lines, consistent with the SaDXR expression level. SaDXR was also stimulated by MeJA and H2O2 in seedling roots. α-Santalol content decreased in response to fosmidomycin, a DXR inhibitor. These results suggest that SaDXR plays an important role in the biosynthesis of photosynthetic pigments, shifting the flux to sandalwood-specific sesquiterpenoids.

Thermos-sensitive genic male sterility (TGMS) is the important genetic resource in two-line hybrid rice breeding. The pollen fertility of TGMS lines is regulated by a single point mutation on the TGMS genes. Based on the single nucleotide polymorphism (SNP) and indel, KASP markers were developed and utilized in rice molecular breeding due to high-through detection with low cost and save time. In this study, we convert the SNPs on TGMS genes including p/tms12-1 and tms9-1 gene to the functional co-dominant KASP marker and used in two-line hybrid rice breeding. We can differentiate the TGMS lines conferring p/tms12-1 or tms9-1 from another TGMS lines by KASP assay. Of them, the genotype of Pei'ai64S and Hua201S containing p/tms12-1 is homozygous GG genotype with blue signal, and the genotype of HengnongS-1 containing tms9-1 is homozygous CC genotype with red signal. KASP assay for tms9-1 gene was proved that the genetic mode is fit to one recessive Mendalian trait. The test of seed purity was performed by KASP marker for the two-line hybrid varieties of Liangyoupeijiu and Hualiangyou1206, which is consistent with the previous dCAPS marker. Moreover, the tms12-1 and tms9-1 gene were pyramided in the same genetic background and the new TGMS lines were generated. Therefore, the KASP marker for TGMS genes developed in this study can be widely used in two-line hybrid rice breeding. It will provide a visual convenient toolkit for breeders to select the target individual plant by the high-throughput detection in the different two-line rice breeding program.

Five chemical elicitors––6-benzyladenine (BA), ethephon (ETH), methyl jasmonate (MeJA), hydrogen peroxide (H2O2) and calcium chloride (CaCl2)––were used to treat 1- and 5-year-old sandal trees (Santalum album L.) to assess their effects on growth, heartwood formation and concrete oil synthesis. The results showed that some newly formed branches in stems that were induced by BA and ETH displayed leaf senescence and developed new smaller and light-green leaves. The relative percentage of concrete oil from the heartwood of water-treated trees (0.65%) was significantly lower than that from trees treated with 4 mM H2O2 (2.85%) and 4 mM BA (2.75%) within one year. Four mM BA, H2O2 and CaCl2 induced a significantly higher level of sesquiterpenoids than heartwood treated with 2 mM of these elicitors. Four mM MeJA induced significantly less sesquiterpenoids than heartwood treated with 2 mM MeJA. Morphological, physiological, and chromatographic–spectrometric technologies were integrated to trace the potential function of these exogenously applied chemical elicitors. The results may have important applications and provide a better understanding of the molecular mechanism of heartwood formation and hardening in young sandalwood trees.

Sandalwood (Santalum album L.) is famous for its unique fragrance derived from the essential oil of heartwood, whose major components are santalols. To understand the mechanism underlying the biosynthesis of santalols, in this study, we cloned two related genes involved in the mevalonate pathway in S. album coding for acetyl-CoA C-acetyl transferase (AACT) and 3-hydroxy-3-methyglutary-CoA synthase (HMGS). These genes were characterized and functionally analyzed, and their expression profiles were also assessed. An AACT gene designated as SaAACT (GenBank accession No. MH018694) and a HMGS gene designated as SaHMGS (GenBank accession No. MH018695) were successfully cloned from S. album. The deduced SaAACT and SaHMGS proteins contain 415 and 470 amino acids, and the corresponding size of their open-reading frames is 1538 bp and 1807 bp, respectively. Phylogenetic trees showed that the SaAACT protein had the closest relationship with AACT from Hevea brasiliensis and the SaHMGS proteins had the highest homology with HMGS from Siraitia grosvenorii. Functional complementation of SaAACT and SaHMGS in a mutant yeast strain deficient in these proteins confirmed that SaAACT and SaHMGS cDNA encodes functional SaAACT and SaHMGS that mediate mevalonate biosynthesis in yeast. Tissue-specific expression analysis revealed that both genes were constitutively expressed in all examined tissues (roots, sapwood, heartwood, young leaves, mature leaves and shoots) of S. album, both genes showing highest expression in roots. After S. album seedlings were treated with 100 μM methyl jasmonate, the expression levels of SaAACT and SaHMGS genes increased, suggesting that these genes were responsive to this elicitor. These studies provide insight that would allow further analysis of the role of genes related to the sandalwood mevalonate pathway in the regulation of biosynthesis of sandalwood terpenoids and a deeper understanding of the molecular mechanism of santalol biosynthesis.

Five chemical elicitors––6-benzyladenine (BA), ethephon (ETH), methyl jasmonate (MeJA), hydrogen peroxide (H2O2) and calcium chloride (CaCl2)––were used to treat 1- and 5-year-old sandal trees (Santalum album L.) to assess their effects on growth, heartwood formation and concrete oil synthesis. The results showed that some newly formed branches in stems that were induced by BA and ETH displayed leaf senescence and developed new smaller and light-green leaves. The relative percentage of concrete oil from the heartwood of water-treated trees (0.65%) was significantly lower than that from trees treated with 4 mM H2O2 (2.85%) and 4 mM BA (2.75%) within one year. Four mM BA, H2O2 and CaCl2 induced a significantly higher level of sesquiterpenoids than heartwood treated with 2 mM of these elicitors. Four mM MeJA induced significantly less sesquiterpenoids than heartwood treated with 2 mM MeJA. Morphological, physiological, and chromatographic–spectrometric technologies were integrated to trace the potential function of these exogenously applied chemical elicitors. The results may have important applications and provide a better understanding of the molecular mechanism of heartwood formation and hardening in young sandalwood trees.

Sandalwood is highly valued for its fragrant heartwood and its extracted oil. The major oil component santalols are terpenoids, which are biosynthesis through the MVA pathway. MK and PMK are the major enzymes on the MVA pathway. Little is known about the genes encoding MK and PMK in Santalum album on its expression regulation mechanism. The analysis of MK and PMK genes and their functions are important for the further study of the biosynthesis of santalol. These results will help to further study the role of MK and PMK genes in S. album santalol biosynthesis. The total RNA of sandalwood leaves was extracted, then the First-strand cDNA synthesis was obtained through the PrimeScript first-strand cDNA synthesis kit. Then sequence comparison and bioinformatics analyses of the genes homology of SaMK and SaPMK with MKs and PMKs, We also investigated subcellular localization of SaMK and SaPMK proteins. Its functional complementation of SaMK and SaPMK in yeast were also investigated. Atlast, MeJA was used to induce tissue-specific analysis and expression profiles of SaMK and SaPMK. The results showed that the full-length cDNA sequences of SaMK and SaPMK were 1409 bp and 1679 bp containing a 1381 bp open reading frame (ORF) encoding a polypeptide of 460 amino acids and a 1527 bp ORF encoding a polypeptide of 508 amino acids, respectively. Sequence comparison and bioinformatics analyses indicated that SaMK and SaPMK showed high homology with MKs and PMKs, respectively from other plant species. Further functional complementation of SaMK in an MK-deficient mutant yeast strain YMR208W and SaPMK in a PMK-deficient mutant yeast strainYMR220W confirmed that cloned SaMK and SaPMK cDNA encode a functional MK and PMK, respectively and mediated MVA biosynthesis in yeast. Tissue expression pattern analysis revealed that SaMK and SaPMK were constitutively expressed in all the tested tissues. SaMK was highly expressed in young leaves but least expressed in sapwood while SaPMK was highly expressed in roots and mature leaves, and least expressed in young leaves.

Sandalwood (Santalum album L.) is highly valued for its fragrant heartwood and extracted oil. Santalols, which are the main components of that oil, are terpenoids, and these are biosynthesized via the mevalonic acid (MVA) pathway. Mevalonate kinase (MK) and phosphomevalonate kinase (PMK) are key enzymes in the MVA pathway. Little is known about the genes that encode MK and PMK in S. album or the mechanism that regulates their expression. To isolate and identify the functional genes involved in santalol biosynthesis in S. album, an MK gene designated as SaMK, and a PMK gene designated as SaPMK, were cloned from S. album. The sequences of these genes were analyzed. A bioinformatics analysis was conducted to assess the homology of SaMK and SaPMK with MK and PMK genes from other plants. The subcellular localization of SaMK and SaPMK proteins was also investigated, as was the functional complementation of SaMK and SaPMK in yeast. Our results show that the full-length cDNA sequences of SaMK and SaPMK were 1409 bp and 1679 bp long, respectively. SaMK contained a 1381 bp open reading frame (ORF) encoding a polypeptide of 460 amino acids and SaPMK contained a 1527 bp ORF encoding a polypeptide of 508 amino acids. SaMK and SaPMK showed high homology with MK and PMK genes of other plant species. Functional complementation of SaMK in a MK-deficient mutant yeast strain YMR208W and SaPMK in a PMK-deficient mutant yeast strain YMR220W confirmed that cloned SaMK and SaPMK cDNA encode a functional MK and PMK, respectively, mediating MVA biosynthesis in yeast. An analysis of tissue expression patterns revealed that SaMK and SaPMK were constitutively expressed in all the tested tissues. SaMK was highly expressed in young leaves but weakly expressed in sapwood. SaPMK was highly expressed in roots and mature leaves, but weakly expressed in young leaves. Induction experiments with several elicitors showed that SaMK and SaPMK expression was upregulated by methyl jasmonate. These results will help to further study the role of MK and PMK genes during santalol biosynthesis in S. album.

Paphiopedilum armeniacum is a rare orchid native to China with high ornamental value. The germination of P. armeniacum seeds is difficult, especially for the mature seeds, which is the major limitation for their large-scale reproduction. This study explored the reasons for seed germination inhibition from the aspects of the important plant endogenous hormone&mdash, abscisic acid (ABA). The major endogenous hormone contents of seeds were determined at different developmental stages. The ABA content was 5.8 ng/g in 73 days after pollination (DAP) for the immature seeds, peaked at 14.6 ng/g in 129 DAP seeds, and dropped to 2.6 ng/g in the late mature stage of the 150 DAP seeds. The reduction of ABA content in the mature seed suggests a possible contribution to the increased expression of CYP707A, an ABA catabolism gene. The germination rate of the immature seeds was reduced to 9% from 69% when 5 &mu, g/mL ABA was added to the Hyponex N026 germination medium. The result showed that ABA can inhibit the germination of P. armeniacum immature seeds. However, for the heavily lignified mature seeds, reduction in endogenous ABA level does not result in an increase in the germination rate. Lignin accumulation in the seed coat imposes the physical dormancy for P. armeniacum. In summary, the germination of P. armeniacum is regulated by both ABA and lignin accumulation.

Paphiopedilum armeniacum is a rare orchid native to China with high ornamental value. The germination of P. armeniacum seeds is difficult, especially for the mature seeds, which is the major limitation for their large-scale reproduction. This study explored the reasons for seed germination inhibition from the aspects of the important plant endogenous hormone—abscisic acid (ABA). The major endogenous hormone contents of seeds were determined at different developmental stages. The ABA content was 5.8 ng/g in 73 days after pollination (DAP) for the immature seeds, peaked at 14.6 ng/g in 129 DAP seeds, and dropped to 2.6 ng/g in the late mature stage of the 150 DAP seeds. The reduction of ABA content in the mature seed suggests a possible contribution to the increased expression of CYP707A, an ABA catabolism gene. The germination rate of the immature seeds was reduced to 9% from 69% when 5 μg/mL ABA was added to the Hyponex N026 germination medium. The result showed that ABA can inhibit the germination of P. armeniacum immature seeds. However, for the heavily lignified mature seeds, reduction in endogenous ABA level does not result in an increase in the germination rate. Lignin accumulation in the seed coat imposes the physical dormancy for P. armeniacum. In summary, the germination of P. armeniacum is regulated by both ABA and lignin accumulation.

Euryodendron excelsum H. T. Chang is a single-type, rare and endangered woody plant unique to China. In this study, young stems were used as explants and cultured on Woody Plant Medium (WPM) supplemented with 5.0 μM 6-benzyladenine (BA), were subcultured for more than 15 times over a total of more than 3 years and finally an efficient axillary shoot proliferation and plantlet regeneration system was established in which one shoot could proliferate an average of 5.1 axillary shoots every 2 months on the medium supplemented with 5.0 μM BA and 0.5 μM α-naphthaleneacetic acid (NAA). Shoots rooted at a moderate frequencies (50.1%) on agarized WPM supplemented with 0.5 μM NAA but 100% of shoots rooted in agar-free vermiculite-based WPM after culture for 2 months. Plantlets, when transplanted to peat soil: vermiculite (1:1), showed the highest 95.1% survival within 1 month.

Backgrounds Paphiopedilum is an important genus of the orchid family Orchidaceae and has high horticultural value. The wild populations are under threat of extinction because of overcollection and habitat destruction. Mature seeds of most Paphiopedilum species are difficult to germinate, which severely restricts their germplasm conservation and commercial production. The factors inhibiting germination are largely unknown. Results In this study, large amounts of non-methylated lignin accumulated during seed maturation of Paphiopedilum armeniacum (P. armeniacum), which negatively correlates with the germination rate. The transcriptome profiles of P. armeniacum seed at different development stages were compared to explore the molecular clues for non-methylated lignin synthesis. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that a large number of genes associated with phenylpropanoid biosynthesis and phenylalanine metabolism during seed maturation were differentially expressed. Several key genes in the lignin biosynthetic pathway displayed different expression patterns during the lignification process. PAL, 4CL, HCT, and CSE upregulation was associated with C and H lignin accumulation. The expression of CCoAOMT, F5H, and COMT were maintained at a low level or down-regulated to inhibit the conversion to the typical G and S lignin. Quantitative real-time RT-PCR analysis confirmed the altered expression levels of these genes in seeds and vegetative tissues. Conclusions This work demonstrated the plasticity of natural lignin polymer assembly in seed and provided a better understanding of the molecular mechanism of seed-specific lignification process.

An efficient regeneration system via shoot organogenesis and somatic embryogenesis from in vitro leaf and root explants was established for Scaevola sericea for the first time. The highest axillary shoot proliferation coefficient (4.8) was obtained on Murashige and Skoog (MS) medium supplemented with 1.0 mg/L 6-benzyladenine (BA) and 0.1 mg/L α-naphthaleneacetic acid (NAA) every 45 days. Young in vitro leaves and roots, which were used as explants, were cultured onto medium supplemented with different plant growth regulators. Our results showed that only cytokinins BA and thidiazuron (TDZ), could induce adventitious shoots and somatic embryos from leaf and root explants. The optimal medium to achieve this was MS medium supplemented with 2.5 mg/L BA and which induced most adventitious shoots (2.7) and somatic embryos (17.3) from leaf explants within 30 days. From root explants, 1.1 adventitious shoots and 7.6 somatic embryos could be induced on MS medium supplemented with 2.5 mg/L TDZ. Histological observation showed that both somatic embryos and adventitious shoots were originated from homogeneous parenchyma and the development of somatic embryos was visible. Maximum rooting percentage (99.0%) was achieved on half-strength MS medium supplemented with 2.5 mg/L NAA. Well-rooted plantlets, which were transplanted into a substrate of pure river sand, displayed a high survival percentage of 91.7% after transplanting for 45 days while the best substrate for plantlet growth was river sand: coral sand (1:1).

Minimization of the lattice thermal conductivity (κL) in thermoelectric (TE) materials is a widely applied strategy to improve the thermoelectric performance of these materials. Dislocations have been demonstrated to be effective in scattering the mid-frequency phonons, which can dramatically reduce the κL in combination with the nanostructures and point defects. Generally, plastic deformation is the most straightforward method to generate dislocations in an alloy. However, most TE materials cannot readily deform plastically due to their brittleness. Herein, we have demonstrated that shock compression is effective in generating high-density dislocations (∼7.9 × 1012 cm−2) in TE materials. Shock compression is an extreme regime of deformation with ultra-high strain rates (>106 s−1) and high pressures (∼GPa), combined with high temperatures during the process. Using this method, multi-scale hierarchical architectures were fabricated in higher manganese silicides (HMS) with nano-sized grains and high-density dislocations. An ultralow lattice thermal conductivity of 1.5 W m−1 K−1 has been achieved in HMS compounds, and the maximum ZT is increased by 47% to 1.0, which is higher than that of most of the ZT values reported for the HMS compounds. These results demonstrate that dense dislocations not only can lower the κL and improve the ZT of HMS, but can also extend the application of the shock compression method to the design of advanced TE materials.

Nb1−xMxFeSb (M = Hf, Zr, Mo, V, Ti; equimolar) thermoelectric materials were prepared by arc melting and subsequent spark plasma sintering. NbFeSb-based half-Heusler phases with a high-entropy lattice were obtained by replacing the Nb sites with multielement M atoms. The lattice thermal conductivity decreased as the M content increased, which mainly resulted from the high entropy effect. A low lattice thermal conductivity of 2.5 W/m K and a high figure of merit of 0.88 were obtained at 873 K, showing the great promise of the high entropy strategy for reducing the lattice thermal conductivity and enhancing the thermoelectric performance.

The inducible accumulation of desired products via in vitro cultures provides an experimental system for researching secondary metabolism in woody plants. This system is convenient, because environmental conditions can be strictly controlled. This is particularly important for East Indian sandalwood (Santalum album L.), a tree with desired sandal oil products that are restricted to the heartwood. In this study, we established a method to induce and proliferate callus from sandalwood shoot explants. Thidiazuron (TDZ) (0.2–1.5 mg/l) could induce the formation of callus, which proliferated rapidly within a month following three successive subcultures in liquid shake culture on Murashige and Skoog (MS) basal medium supplemented with 0.8–1.0-mg/l TDZ. Callus cultured in this liquid medium for 7 days was co-cultured with fungi, either Colletotrichum gloeosporioides or Penidiella kurandae. Gas chromatography–mass spectrometry (GC–MS) analysis of the solvent extract by chemical anhydrous diethyl ether of callus co-cultured with C. gloeosporioides showed the presence of santalenes and bisabolene, which are the precursors of santalol. However, another fungus, P. kurandae, could not induce santalenes or bisabolene. This study provides an opportunity to further studies on the santalene and bisabolene biosynthetic signaling pathway and the fungal endophyte–plant interaction in sandalwood.

La 1- x Sr x CoO 3 ( x = 0, 0.1) nanoparticles were synthesized by the simple sol-gel technique. Based on characteristics by scanning electron microscope, transmission electron microscope and X-ray diffractometer, the nanoparticles with the size distributed ranging from 40 to 80 nm all show a single phase with rhombohedral distortion perovskite structure. The sensors exhibit excellent acetone sensing performance at room temperature (∼25 °C), especially showing a nearly linear relation with the acetone concentration between 10 and 100 ppm. Sr 2+ doping can bring holes in the p -type semiconductor, thus increasing the resistance variation range of LaCoO 3 and enhancing the sensing performance. It suggests that the La 1- x Sr x CoO 3 nanoparticles can be considered as a potential candidate for acetone detecting at room temperature.

Sandalwood essential oil or terpenoids are highly valued. This review summarizes several methods for increasing yields of sandalwood essential oil or terpenoids and the molecular mechanisms of sandalwood terpene biosynthesis. Sandalwood is highly valued for its aromatic heartwood and essential oil, which is not only broadly applied in the fragrance industry, but also has various biological activities: anti-cancer, anti-tumor, anti-viral, anti-diarrhoeal, etc. The main contributors of sandalwood essential oil fragrance are (Z)-α-santalol and (Z)-β-santalol. Global sandalwood resources are often in short supply because of slow growth, habitat destruction, illegal use of natural stocks, over exploitation, plant disease and insect pests. Thus, various methods are used to overcome these shortcomings to obtain more sandalwood essential oil or terpenoids. At first, an understanding of the molecular mechanism of sandalwood terpenoid biosynthesis is urgently required. Here, we review the mechanism of sandalwood terpenoid biosynthesis and multiple strategies for increasing the yield of essential oil and obtaining sandalwood terpenoids by biotechnological methods. Three major topics are discussed: (1) the metabolic pathway of sandalwood terpenoid biosynthesis, (2) how to obtain sandalwood terpenoids or essential oil by chemical synthesis, the application of elicitors and the plant cell culture, and (3) heterologous synthesis of sandalwood terpenoids.

Accidents at TMI, USA and Fukushima, Japan have emphasized the need for hydrogen mitigation during nuclear plant accidental conditions, especially during severe accidents which will be no power, massive hydrogen, high temperature, long-term operation, and poisoning environment. Passive autocatalytic recombiners with catalyst sheets are the promising way to deal with the situation in severe accidents. Here we report a new kind of catalyst sheets based on stainless steel supported Pd nanoclusters prepared by electroless deposition route. The catalyst sheets were characterised for morphology and composition of surface by SEM and EDS. The catalytic activity of the catalyst sheets has been evaluated under the conditions of higher temperature, long-term operation and poisoning environments. The catalyst sheets showed high activity and good stability either operating above 500 °C for 24 h or continuous operating for 25 days. For the obtained catalyst sheets after exposed to methanal, iodine vapor and BaSO 4 aerosol respectively with corresponding concentrations higher than SA conditions, the start-up time for H 2 -O 2 recombination reaction was less than 1 min and the catalytic efficiency was more than 90%. These results indicate the potential application of this type of catalyst sheets for hydrogen mitigation in severe accidents.

Bi0.95La0.05Fe0.8M0.2O3 (M = Cr, Co, Al) ceramics have been prepared by high pressure synthesis and their structure, magnetic, thermal, and optical properties have been investigated. X-ray diffraction suggests the pure phase formation with rhombohedral structure in all samples. The structural distortion induced by dopants is further analyzed by Raman spectra. The SEM investigation reveals that Cr and Al substitution does not affect the morphologies of Bi0.95La0.05FeO3 ceramics, while Co substitution significantly reduces the grain sizes and uniforms the morphology. The effect of substitution on the magnetic properties of Bi0.95La0.05FeO3 is different depending on M due to different mechanisms. More interestingly, Co substitution induces a change in the spin structure from a cycloidal space modulated spin structure to a collinear G-type antiferromagnetic structure, which results in obviously enhanced magnetization at room temperature. Optical studies show a sharp absorption in the visible region for all samples. The band gap values of Bi0.95La0.05FeO3 and Bi0.95La0.05Fe0.8M0.2O3 ceramics with M = Cr, Co, and Al are estimated to be 2.30, 2.06, 2.12 and 2.27 eV, respectively.

A highly efficient protocol for the induction of adventitious shoots from young internode and root explants of a semiparasitic medicinal herb Monochasma savatieri Franch ex Maxim was developed. MS basal medium supplemented with 5 µM thidiazuron (TDZ) induced 32 adventitious shoots/explant, which was double the number obtained using the same concentration of 6-benzyladenine (BA). Hyperhydric shoots were observed when 10 µM of any cytokinin was added to MS media. Use of any cytokinin at 2.5 µM produced an average of 14–21 adventitious shoots/root explant. Shoots formed roots in vitro more effectively than α-naphthaleneacetic acid when indole-3-butyric acid and indole-3-acetic acid were used at 1.0 µM. Two-month-old rooted plantlets were transplanted to vermiculite and 70% survived after 4 months.

Today's industry lacks the compact, autonomous, and precise tools to quickly and accurately model interior spaces. With advancements in virtual reality headsets, creating an accurate three-dimensional model of interior or exterior environments possesses many valuable uses. The applications of these models can be used for precise measurement of complex environments, architectural preservation, and the creation of virtual interactive training environments for military applications. The scope of this design was to create a spatial mapping system that is capable of rapid deployment to autonomously map a desired environment. The system utilizes a ZED stereo camera for depth mapping and matrix-meshing that creates a framework for the virtual environment build-up in the Unity software platform. Through testing and analysis, design improvements are identified, and it is determined that the design of an autonomous spatial analyzer is a practical and affordable option for a variety of applications.

Bisabolene-type sesquiterpenoids, which have multiple bioactivities, including anticancer activity, are one of the main groups of compounds in the essential oil extracted from Santalum album L. and other Santalum species. Bisabolene synthetase (SaBS) is a key enzyme for the synthesis of bisabolene in S. album, but the regulation of the SaBS gene&rsquo, s expression is poorly understood. In this study, a 1390-bp promoter sequence of the SaBS gene was isolated from the leaves of six-year-old S. album. A bioinformatics analysis showed that certain environment stresses and phytohormone-activated cis-acting elements were distributed in different regions of the SaBS promoter (PSaBS). Transgenic Arabidopsis carrying full-length PSaBS had significantly higher &beta, glucuronidase (GUS）activity than the untreated control after treatment with salicylic acid (SA), suggesting that PSaBS is a SA-inducible promoter. Histochemical GUS staining and GUS fluorometric assays of transgenic Arabidopsis showed that the GUS activity directed by PSaBS was mainly expressed in stem tissue, followed by leaves and flowers. Moreover, different regions of PSaBS showed significantly different GUS activity. A 171-bp fragment upstream of the transcriptional initiation codon (ATG) is the core promoter region of PSaBS. Our results provide insight into and a greater understanding of the transcriptional regulation mechanism of the SaBS gene, which could serve as an alternative inducible promoter for transgenic plant breeding.

Primulina tabacum Hance (Gesneriaceae) is a calciphilous perennial herb. There are only eight wild populations with less than 10,000 individuals in Southern China. The distribution, conservation status, ecological and biological characteristics, genetic diversity, reproductive biology, tissue culture, and horticulture of P. tabacum were studied before reintroduction. Thousand in vitro-propagated P. tabacum plantlets were used to reintroduce at three of the plant’s historical and extant habitats. About 10% of the transplanted seedlings survived by 2012. More than 200 next-generation individuals were found in 2018. Facilitation between the species and mosses is important for the reintroduction success.

Additional file 1: Figure S1. (A) Correlation indices between different samples. (B) Principal component analysis performed on the 15 samples. A: 65 DAP, B: 87 DAP, C: 108 DAP, D: 122 DAP, E:150 DAP. Figure S2. Functional annotations of the unigenes of P. armeniacum seed transcriptome. (A) NR annotated species distribution map similar to the Paphiopedilum armeniacum transcriptome. Dendrobium catenatum shows the highest similarity. (B) GO function annotation. The most abundant functions are binding and catalytic activity in terms of molecular function and metabolic process and cellular process in terms of biological process. Figure S3. Additional data for qPCR assays. (A) The quality of RNA used for qPCR assessed by agarose gel electrophoresis. 1–4: 66 DAP, 5–8:87 DAP, 9–12: 108 DAP, 13–16: 122 DAP, 17–20: 150 DAP. Lanes 1 and 2 are the 28S and 18S RNA bands. (B) Quantification of RNA used for qPCR estimated by Nanodrop One and Agilent 2100 Bioanalyzer. (C) Melt curve from qPCR of PAL1, PAL2, C4H, 4CL, HCT, CCoAOMT1, CCoAOMT2, F5H, COMT1, and COMT2 genes. The single peak observed presented the pure and single amplicon resulted from the assay. Figure S4. (A) Distribution of differentially expressed transcription factors (TFs); (B) Expression profiles of MYBs potentially related to lignin synthesis.

Dayaoshania cotinifolia W. T. Wang is a perennial herb which is an endemic species in the Guangxi Zhuang Autonomous Region, China. It is a relatively primitive species of the Gesneriaceae. It was listed as one of the prioritized protected key wild plants of China and a critical endangered species because of its small population, narrow distribution, and disturbance of human activity. We collected some fruits of D. cotinifolia to South China Botanical Garden for seed germination test. It showed that gibberellin (GA3) could enhance seed germination, which indicated that the seed has dormancy period after seeds become matured. In another test, we inoculated the sterilized seeds on MS medium for in vitro culture. Half a month later, the seed germinated and the initiate cotyledons were used as explants to induce adventitious shoots. After that, an efficient in vitro propagation and regeneration system via shoot organogenesis was established from young leaf explants. Plantlets were transplanted to a mixture of sand, vermiculite, and humus (1:1:1) with 92% survived. We have totally propagated 1000 relatively strong plantlets, and they were transplanted in the mountain slopes in May of 2013 in Jinxiu Yaoshan Nature Reserve. About 452 plants were still alive after 1 year as we returned to investigate the reintroduction area. One and half years later, about 126 plants had grown up and flowered and even seed reproduction was noted. In October 2017, over 500 plantlets from cutting propagation of leaves were transplanted in Jinxiu Yaoshan Nature Reserve. Three hundred eighty plants were still alive after 1 year later, and most of them flowered and seed reproduction was also noted. These results indicated that reintroduction of D. cotinifolia was successful.

Virtual reality (VR) is a great new technology which has extensive applications, and it is imperative that there is a way to use VR comfortably. This will allow VR to become an everyday tool, creating a more interactive world. With more VR integration new technologies can be created and allow VR to expand further into fields like therapy or military training. However, VR comes with some unfortunate side effects. The cybersickness that many people experience when using a VR system has been shown to trigger a thermoregulatory response that causes sweating, the sensation of being excessively hot, as well as nausea. These symptoms of cybersickness make it uncomfortable to use a VR system for any long period of time. In order to combat this, the authors present a device which can effectively cool the user to extend the time duration a user can comfortably use a VR system.

Sleep disorders impair the quality of life for many individuals, but often go undiagnosed and untreated due to the cost and sleep-disturbing aggravation of polysomnography, the clinical sleep test. Simpler sleep monitoring systems that could be used at home may provide useful health information. A 2D grid of force sensors within a mat beneath the thorax of a sleeping subject has been reported to enable monitoring of respiration during sleep. A physical model of a thorax over such a 2D grid of force sensors may enable more tests and perturbations of parameters than could be done using only human subjects. The purpose of this project was to develop and test a physical model of a thorax undergoing volume changes, and measuring the changes in force by a grid of force sensors under the model. A prototype system was developed. Early testing shows promise for being able to monitor the changes in force as volume of the model changes. More development and testing are required toward development of improved algorithms and systems for sleep monitoring mats.

WRKY proteins are a large superfamily of transcription factors that are involved in diverse biological processes including development, as well as biotic and abiotic stress responses in plants. WRKY family proteins have been extensively characterized and analyzed in many plant species, including Arabidopsis, rice, and poplar. However, knowledge on WRKY transcription factors in Santalum album is scarce. Based on S. album genome and transcriptome data, 64 SaWRKY genes were identified in this study. A phylogenetic analysis based on the structures of WRKY protein sequences divided these genes into three major groups (I, II, III) together with WRKY protein sequences from Arabidopsis. Tissue-specific expression patterns showed that 37 SaWRKY genes were expressed in at least one of five tissues (leaves, roots, heartwood, sapwood, or the transition zone), while the remaining four genes weakly expressed in all of these tissues. Analysis of the expression profiles of the 42 SaWRKY genes after callus was initiated by salicylic acid (SA) and methyl jasmonate (MeJA) revealed that 25 and 24 SaWRKY genes, respectively, were significantly induced. The function of SaWRKY1, which was significantly up-regulated by SA and MeJA, was analyzed. SaWRKY1 was localized in the nucleus and its overexpression improved salt tolerance in transgenic Arabidopsis. Our study provides important information to further identify the functions of SaWRKY genes and to understand the roles of SaWRKY family genes involved in the development and in SA- and MeJA-mediated stress responses.

Developing new advanced nonenzymatic electrochemical nano-sensors for glucose detection has attracted intensive attraction. In this work, we designed a novel nanocomposite nonenzymatic glucose sensor by fabricating hierarchically nanostructured metal nickel on titania nanowire arrays, which was loaded on a transparent conductive substrate (i.e., fluorine-doped tin oxide, FTO) surface by mild hydrothermal method. Due to the large surface area of the hierarchically nanostructured Ni and fast electron transfer of the TiO2 nanowire arrays electrode, the nanocomposite electrode shows excellent electrochemical activity toward the oxidation of glucose. The electrode exhibits high sensitivity in detecting glucose concentration (1472 μA mM−1 cm−2) with a wide linear range from 2×10−4 M to 2×10−3 M, fast response time (within 5 s), and small detection limit (10 μM) (S/N = 3). The good analytical performance, low cost and simple preparation method make this novel electrode material promising for the development of effective glucose nonenzymatic glucose sensor.

Background: WRKY proteins are a large superfamily of transcription factors that are involved in diverse biological processes including development, as well as biotic and abiotic stress responses in plants. WRKY family proteins have been extensively characterized and analyzed in many plant species, including Arabidopsis , rice and poplar. However, knowledge on WRKY transcription factors in S antalum album is scarce. Results: Based on S . albu m genome and transcriptome data, 64 SaWRKY genes were identified in this study. A phylogenetic analysis based on the structures of WRKY protein sequences divided these genes into three major groups (I, II, III) together with WRKY protein sequences from Arabidopsis . Tissue-specific expression patterns showed that 37 SaWRKY genes were expressed in at least one of five tissues (leaves, roots, heartwood, sapwood, or the transition zone) while the remaining four genes were weakly expressed in all of these tissues. Analysis of the expression profiles of the 42 SaWRKY genes after callus was stimulated by salicylic acid (SA) and methyl jasmonate (MeJA) revealed that 34 and 19 SaWRKY genes, respectively were significantly induced. The function of SaWRKY1 , which was significantly up-regulated by SA and MeJA, was analyzed. SaWRKY1 was localized in the nucleus and its overexpression improved salt tolerance in transgenic Arabidopsis . Conclusions: Our study provides important information to further identify the functions of SaWRKY genes and to understand the roles of SaWRKY family genes involved in development and in SA- and MeJA-mediated stress responses.