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Juglans regia L. and J. sigillata D. have a long cultivation history in China. With the purpose of detecting interspecific and intraspecific genetic variation, 35 clonal cultivars of J. regia, J. sigillata, J. sigillata×J. regia and J. hopeiensis Hu. (J. mandshurica Maxim. ×J. regia) were selected from a broad geographic range and applied in amplified-fragment length polymorphism (AFLP) analysis. Clear-cut AFLP profiles were produced using 9 EcoR I/Mse I primer combinations. As for J. regia, J. sigillata and their hybrids, the percentages of polymorphic bands (PPBs) averaged 93.86%, 93.94% and 60.46%; the observed number of alleles (Na) averaged 1.5370, 1.6389 and 1.2593; the effective number of alleles (Ne) averaged 1.2582, 1.2543 and 1.1646; Nei's gene diversity (H) scored 0.1560, 0.1556 and 0.0951; Shannon’s information index (I) averaged 0.2402, 0.2459 and 0.1414, respectively. These results implied a moderate level of genetic diversity within the investigated species. The total gene diversity (Ht = 0.1596) can be distributed into intra- (Hs = 0.1356) and inter- (Dst = 0.0240) species gene diversity. The proportion of the distributed genetic diversity among populations (Gst) was 0.1505, indicating that only 15% of the total gene diversity was attributed to differences between species. The factorial correspondence analysis (FCA) and unweighted pair-group method of arithmetic averages (UPGMA) analysis revealed a close genetic distance between these two species.

Catalpa speciosa (Warder) Engelm. is a precious Catalpa tree widely used as a large ornamental shade tree. In this study, the complete chloroplast genome was assembled from Illumina sequencing data. The completed plastome was 158,239 bp in length, including a large single copy (LSC) region of 85,036 bp, a small single copy (SSC) region of 12,639 bp, and a pair of inverted repeat (IR) regions of 30,282 bp. The overall GC content of the genome was 38.09%, and the corresponding values of the LSC, SSC and IR regions were 36.44%, 33.57%, and 41.35%, respectively. A total of 129 genes were annotated, including 83 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analysis was carried out based on complete plastome sequences of C. speciose and 11 other species from Bignoniaceae family. The newly characterized complete chloroplast genome will provide essential data for further studies of C. speciosa.

Paradox is one of the most important rootstock resources in USA and China walnut industry. In this study, we characterized the complete chloroplast genome of Paradox (Juglans major × J. regia) based on next generation sequencing. The circular complete chloroplast genome was 160,324 bp in length, containing a large single-copy (LSC) region of 89,852 bp, and a small single-copy (SSC) region of 18,410 bp. These two regions were separated by a pair of inverted repeat regions (IRa and IRb) of 26,031 bp each. A total of 131 functional genes were encoded, consisted of 87 protein-coding genes, 36 tRNA genes, and 8 rRNA genes. The overall GC content of the chloroplast genome was 36.1% and the GC contents of the LSC, SSC, and IR regions were 33.7, 29.9, and 42.6%, respectively. The phylogenetic analysis by Neighbor-Joining showed that Paradox was relatively closely related to J. major compared to other species of Juglans genus. This complete chloroplast genome will provide valuable insight into evolution, molecular breeding, and phylogenetic analysis of Juglans species.

Catalpa ovata G. Don is a precious Catalpa tree known as a source of valuable timber and compounds for medicinal usage. In this study, we reported its complete chloroplast genome assembled from Illumina pair-end sequencing data. The completed plastome was 158,355 bp in length, including a large single copy (LSC) region of 85,007 bp, a small single copy (SSC) region of 12,676 bp, and a pair of inverted repeat (IR) regions of 30,336 bp. The overall GC content of the genome was 38.07%, and the corresponding values of the LSC, SSC and IR regions were 36.42%, 33.54%, and 41.33%, respectively. A total of 129 genes were annotated, including 83 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analysis strongly supported that Tecomaria capensis was the most closely related species to C. ovata. The newly characterized complete chloroplast genome of C. ovata will provide essential data for further investigation of this precious species.

Although the effects of fertilization and microbiota on plant growth have been widely studied, our understanding of the chemical fertilizers to alter soil chemical and microbiological properties in woody plants is still limited. The aim of the present study is to investigate the impact of long-term application of chemical fertilizers on chemical and microbiological properties of root-associated soils of walnut trees. The results show that soil organic matter (OM), pHkcl, total nitrogen (TN), nitrate-nitrogen (NO3−), and total phosphorus (TP) contents were significantly higher in non-fertilized soil than after chemical fertilization. The long-term fertilization led to excessive ammonium-nitrogen (NH4+) and available phosphorus (AP) residues in the cultivated soil, among which NH4+ resulted in soil acidification and changes in bacterial community structure, while AP reduced fungal diversity. The naturally grown walnut trees led to an enrichment in beneficial bacteria such as Burkholderia, Nitrospira, Pseudomonas, and Candidatus_Solibacter, as well as fungi, including Trichoderma, Lophiostoma, Phomopsis, Ilyonectria, Purpureocillium, Cylindrocladiella, Hyalorbilia, Chaetomium, and Trichoglossum. The presence of these bacterial and fungal genera that have been associated with nutrient mobilization and plant growth was likely related to the higher soil OM, TN, NO3−, and TP contents in the non-fertilized plots. These findings highlight that reduced chemical fertilizers and organic cultivation with beneficial microbiota could be used to improve economic efficiency and benefit the environment in sustainable agriculture.

Upconversion luminescence properties of (Yb3+/Er3+): NaYF4 and Mn2+ doped (Yb3+/Er3+): NaYF4 nanocrystals have been investigated under pulsed high magnetic field. The emission ratio of red to green of the bare (Yb3+/Er3+): NaYF4 nanocrystals increases by about 42% as the magnetic field increases from 0 T to 40 T. While for Mn2+ doped (Yb3+/Er3+): NaYF4 nanocrystals, the ratio keeps almost unchanged due to the energy transferring between Mn2+ and Yb3+/Er3+. The effects of temperature on the upconversion emissions are also compared for the two types of nanocrystals. Our observations have prospective applications in biological imaging and magnetic field detection. [ABSTRACT FROM AUTHOR]

Upconversion luminescence properties of (Yb3+/Er3+): NaYF4 and Mn2+ doped (Yb3+/Er3+): NaYF4 nanocrystals have been investigated under pulsed high magnetic field. The emission ratio of red to green of the bare (Yb3+/Er3+): NaYF4 nanocrystals increases by about 42% as the magnetic field increases from 0 T to 40 T. While for Mn2+ doped (Yb3+/Er3+): NaYF4 nanocrystals, the ratio keeps almost unchanged due to the energy transferring between Mn2+ and Yb3+/Er3+. The effects of temperature on the upconversion emissions are also compared for the two types of nanocrystals. Our observations have prospective applications in biological imaging and magnetic field detection. [ABSTRACT FROM AUTHOR]

We report on ordered nanoporous films exhibiting a unique magneto-plasmon based response, fabricated by nanosphere-assisted physical deposition. This work focuses on multi-layer Ag/CoFeB/Ag films as examples of such structures. Their microstructure dependent magnetic properties, localized surface plasmon resonance (LSPR) and magneto-optical Kerr effect were investigated. The observed effects of nanopores and Ag layers on the magnetic properties indicate the synergistic interaction between nanopores and Ag layers leading to an enhancement of the ferromagnetic character of the CoFeB film. LSPR spectra reveal that the introduction of Ag layers enhances the light transmission in the nanoporous CoFeB films (having pore sizes exceeding the wavelength of light) due to an enhanced interaction of light with surface plasmons. Periodic nanoporous Ag/CoFeB/Ag films covered by Ag capped nanospheres show a much larger extinction than uncovered nanoporous Ag/CoFeB/Ag films. The correlation between the magneto-optical Kerr effect and the nanostructures suggests a field-tunable Kerr effect owing to the magneto-electric coupling between the magnetic layer and the Ag layers, which is enhanced by the nanopores. These hybrid nanostructures are expected to offer potential applications in photovoltaic cells and for magneto-optic sensors. [ABSTRACT FROM AUTHOR]

A more efficient model of the quantum Stackelberg duopoly is proposed by using the asymmetric quantization scheme of Qin et al. In this model, two entanglement factors α and γ are introduced, which greatly expands the functions of the previously reported symmetric one. By choosing proper values of α and γ, one can better manage the market, such as suppressing the first-mover advantage and enhancing the second-mover profit to avoid abuse of oligopolistic competition, and optimizing the total quantity of the products, so to overcome the deficiencies of “first mover always wins" and “positive quantum entanglement always reduces the total quantity" in the symmetric model. The proposed model here is believed to be a good tool for the government and the department to improve the economic efficiency and develop the market. [ABSTRACT FROM AUTHOR]