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SUMMARY: Bermudagrass (Cynodon dactylon) is a globally distributed, extensively used warm‐season turf and forage grass with high tolerance to salinity and drought stress in alkaline environments. However, the origin of the species and genetic mechanisms for salinity tolerance in the species are basically unknown. Accordingly, we set out to study evolution divergence events in the Cynodon genome and to identify genes for salinity tolerance. We developed a 604.0 Mb chromosome‐level polyploid genome sequence for bermudagrass 'A12359' (n = 18). The C. dactylon genome comprises 2 complete sets of homoeologous chromosomes, each with approximately 30 000 genes, and most genes are conserved as syntenic pairs. Phylogenetic study showed that the initial Cynodon species diverged from Oropetium thomaeum approximately 19.7–25.4 million years ago (Mya), the A and B subgenomes of C. dactylon diverged approximately 6.3–9.1 Mya, and the bermudagrass polyploidization event occurred 1.5 Mya on the African continent. Moreover, we identified 82 candidate genes associated with seven agronomic traits using a genome‐wide association study, and three single‐nucleotide polymorphisms were strongly associated with three salt resistance genes: RAP2‐2, CNG channels, and F14D7.1. These genes may be associated with enhanced bermudagrass salt tolerance. These bermudagrass genomic resources, when integrated, may provide fundamental insights into evolution of diploid and tetraploid genomes and enhance the efficacy of comparative genomics in studying salt tolerance in Cynodon. Significance Statement: We have successfully sequenced the first heterozygous, tetraploid genome of Cynodon dactylon, a key warm‐season turfgrass and forage crop. Our GWAS analysis has identified genes linked to vital agronomic traits, enhancing our understanding of bermudagrass cultivation. [ABSTRACT FROM AUTHOR]

The phylogeny of diploid species in the genus has been studied intensively. Although the origin of American polyploid species has been analyzed using multiple-copy internal transcribed spacer sequences, the origins of these species in Hordeum remain unclear. The objectives of our study were to elucidate the origins of American polyploid species and to explore phylogenetic relationships of these polyploids to diploid Hordeum and other diploid species in Triticeae using a single copy of a nuclear gene, disrupted meiotic cDNA1 ( DMC1). DMC1 sequences from nine Hordeum polyploid species were analyzed. Sequence comparisons revealed that one copy of sequences from polyploid species , , and showed a 82 bp miniature inverted-repeat terminal element (MITE) ( Stowaway) insertion, which was also detected in the Triticeae diploid species species (W genome) and (Ta genome). Maximum parsimony and Bayesian analysis suggested that diploid subsp. is one ancestor of polyploids , H. brachyantherum subsp. , , and . The other ancestor of tetraploid H. depressum is probably . Hordeum cordobense was suggested to be one of the genome donors to hexaploid H. procerum. The diploid and tetraploid H. tetraploidum were suggested as the parents to hexaploid species . The result is that one sequence from each of three Hordeum tetrapolyploids, including H. fuegianum, H. jubatum, and H. tetraploidum, and one from Hordeum hexaploid H. arizonicum fall outside the Hordeum clade of the DMC1 phylogenetic tree, therefore representing another example of complex evolutionary history. Our data may shed light on future phylogenetic studies in Triticeae, especially for the polyploids, by broadening the scope of investigations through sampling more genome types in Poaceae, not only from the tribe Triticeae. [ABSTRACT FROM AUTHOR]

Schematic mechanism of photocatalytic H 2 evolution over Pt/HTi 2 NbO 7 nanosheets. • Pt/HTi 2 NbO 7 nanosheets are prepared by different strategies. • Pt/HTi 2 NbO 7 nanosheets via photoreduction exhibits enhanced H 2 evolution activity. • The Pt nanoclusters on the nanosheets effectively improve the photogenerated charge separation. • The synergistic effect between Pt and the nanosheets greatly enhance the hydrogen evolution. Photocatalytic hydrogen production, as an ideal strategy for solar-to-fuel conversion, remains the great challenges in designing the highly efficient photocatalytic systems. Herein, the monolayer HTi 2 NbO 7 nanosheets with the thickness of 1.65 nm are developed as photocatalysts coupled with Pt nanoparticles for hydrogen production from water. The Pt nanocluster/HTi 2 NbO 7 nanosheets prepared via an in situ process showed the better photocatalytic activity for H 2 evolution than that obtained by a chemical reduction. The higher dispersity and more closely interface contact between the nanosheets and Pt nanoclusters would promote the transfer of the photogenerated carriers. A synergistic photocatalytic mechanism for monolayer nanosheets and Pt nanocluster would be proposed to elucidate the high efficient hydrogen production. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid nano-material has a significant potential for enhancing the charge separation efficiency of photocatalyst. However, it remains an important issue to controllable synthesis new hybrid system with unique structure and earth-abundant materials for boosting photocatalytic hydrogen revolution. We report a facile one-step hydrothermal strategy to fabricate a novel Titania/β-cyclodextrin (TiO 2 /β-CD) organic-inorganic hybrid nano-material with an alveolate structure. In this hybrid system, β-CD not only played a critical role in alveolate structure formation, but also served as a bridge connecting target molecular and active sites on the TiO 2 surface to facilitate the separation and transfer of the photoexcited electrons with prolonged lifetime. As a result, this alveolate TiO 2 /β-CD composite exhibited outstanding photocatalytic activity and a H 2 evolution rate of 725 μmol/g·h was achieved over TiO 2 /β-CD which was 14 times of bare TiO 2 under simulated sunlight. This work paves a way for controllable synthesis of novel organic-inorganic hybrid nano-material with distinct structure for efficient photocatalysis. Image 1 • A novel alveolate organic-inorganic hybrid has been successfully prepared. • The hybrid composite exhibited outstanding photocatalytic activity. • The H 2 evolution rate of TiO 2 /β-CD has a good durability. • This work paves a way for controllable synthesis of organic-inorganic TiO 2. • Limited reports on the photocatalytic water splitting of the TiO 2 /β-CD. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Novel hierarchical coral-like porous P-doped g-C 3 N 4 tubes were successfully prepared. • The hybrid 1D/2D heterojunction of P-doped g-C 3 N 4 tubes exhibited enhanced photocatalytic activity for H 2 evolution. • The incorporation of P-doping and tubular structure with nanosheets were responsible for the improved performance. • A possible photocatalytic mechanism and nanostructure formation process were proposed. Abstract Developing novel methods to prepare hollow one-dimensional (1D) carbon nitride (g-C 3 N 4) nanostructure is highly attractive in photocatalytic water splitting for hydrogen production. Herein, a simple, self-assembly synthesis of coral-like 3D porous P-doped g-C 3 N 4 tubes (PCNT) by the combination of pyrolysis and freeze-drying method was reported. Attributed to the integrated merits of 1D tubular structure, 2D nanosheets and phosphorus doping, the as-prepared hollow PCNT exhibits superior photocatalytic activity under visible light irradiation. Owing to their higher specific surface area, enhanced light absorption, and better charge carrier separation and transfer, the maximum apparent photocatalytic hydrogen evolution rate of PCNT is 2020 μmol g−1 h−1, which is about 4.7 folds and 22.4 folds than that of g-C 3 N 4 tubes and pristine bulk g-C 3 N 4 , respectively. Moreover, a possible photocatalytic mechanism and nanostructure formation process based on the experimental results are proposed. The novel growth strategy developed here may offer a new avenue for the rational design and synthesis of potentially efficient photocatalyst with 1D/2D integrated nanoarchitecture. [ABSTRACT FROM AUTHOR]

Abstract: Mitochondrial genome (mitogenome) can provide information for genomic structure as well as for phylogenetic analysis and evolutionary biology. In this study, we present the complete mitogenome of the atlas moth, Attacus atlas (Lepidoptera: Saturniidae), a well-known silk-producing and ornamental insect with the largest wing surface area of all moths. The mitogenome of A. atlas is a circular molecule of 15,282bp long, and its nucleotide composition shows heavily biased towards As and Ts, accounting for 79.30%. This genome comprises 13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and an A+T-rich region. It is of note that this genome exhibits a slightly positive AT skew, which is different from the other known Saturniidae species. All PCGs are initiated by ATN codons, except for COI with CGA instead. Only six PCGs use a common stop codon of TAA or TAG, whereas the remaining seven use an incomplete termination codon T or TA. All tRNAs have the typical clover-leaf structure, with an exception for tRNASer (AGN). The A. atlas A+T-rich region contains non-repetitive sequences, but harbors several features common to the Bombycoidea insects. The phylogenetic relationships based on Maximum Likelihood method provide a well-supported outline of Saturniidae, which is in accordance with the traditional morphological classification and recent molecular works. [Copyright &y& Elsevier]

• PANI-Ag-CN photocatalyst with sandwich structure formed Z-scheme heterojunction. • PANI-Ag-CN enables Ag nanoparticles to act as the charge transfer intermediate. • Ultra-thin nanosheet can rapidly transfer photo-generated charges from inside to surface. • Hydrogen production of PANI-Ag-CN is 5048 μmol•g−1•h−1 which is 43.52 times higher than g-C 3 N 4. • Photocurrent of PANI-Ag-CN is 1.9 × 10−6 A/cm2, which is 5.94 times higher than g-C 3 N 4. In this work, we report a sandwich structure of PANI-Ag-CN photocatalyst, which is stacked layer by layer with g-C 3 N 4 and PANI ultra-thin two-dimensional nanosheets and Ag nanoparticles are embedded as interlayers. The Z-scheme heterojunction can be formed in this sandwich structure of PANI-Ag-CN photocatalyst, where Ag nanoparticles act as the charge transfer intermediate, leading to the annihilation of the holes of g-C 3 N 4 and the electrons of PANI, and thus the strong reductive electrons and the strong oxidative holes can be left at the CB of g-C 3 N 4 and VB of PANI, respectively. Meanwhile, the short charge transfer and the large number of active sites on the ultra-thin two-dimensional nanosheets are proved beneficial for to the photocatalytic hydrogen evolution from water. The PANI-Ag-CN photocatalyst exhibits an increased hydrogen evolution activity of 5048 μmol·g−1·h−1, which is 43.52-fold higher than that of g-C 3 N 4 and 58.02-fold higher than that of bulk g-C 3 N 4. Moreover, the photocurrent of PANI-Ag-CN is 1.9 × 10−6 A/cm2, which is 5.94 times higher than that of g-C 3 N 4. [ABSTRACT FROM AUTHOR]