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Orchids are horticultural plants with significant ornamental and economic value. Increasing market circulation and rising trade in orchids is forcing breeders to develop varieties with unique characteristics, including flower color, morphology, and resistance using a range of approaches, including traditional and molecular breeding. Advances in high-throughput technologies have generated extensive data sets with greater sequencing depths and broader coverage, providing the potential for discovering new genes/pathways that give rise to key traits. Several attempts have been made to use emerging molecular and omics methods to accelerate the breeding process in certain of the commercially valuable orchids. This review consolidates current approaches and achievements in orchid breeding and discusses their future applications for improving the resistance, ornamental, and other valuable characteristics of these plants.

The wood sorrel family, Oxalidaceae, is mainly composed of annual or perennial herbs, a few shrubs, and trees distributed from temperate to tropical zones. Members of Oxalidaceae are of high medicinal, ornamental, and economic value. Despite the rich diversity and value of Oxalidaceae, few molecular markers or plastomes are available for phylogenetic analysis of the family. Here, we reported four new whole plastomes of Oxalidaceae and compared them with plastomes of three species in the family, as well as the plastome of Rourea microphylla in the closely related family Connaraceae. The eight plastomes ranged in length from 150,673 bp (Biophytum sensitivum) to 156,609 bp (R. microphylla). Genome annotations revealed a total of 129–131 genes, including 83–84 protein-coding genes, eight rRNA genes, 37 tRNA genes, and two to three pseudogenes. Comparative analyses showed that the plastomes of these species have minor variations at the gene level. The smaller plastomes of herbs B. sensitivum and three Oxalis species are associated with variations in IR region sizes, intergenic region variation, and gene or intron loss. We identified sequences with high variation that may serve as molecular markers in taxonomic studies of Oxalidaceae. The phylogenetic trees of selected superrosid representatives based on 76 protein-coding genes corroborated the Oxalidaceae position in Oxalidales and supported it as a sister to Connaraceae. Our research also supported the monophyly of the COM (Celastrales, Oxalidales, and Malpighiales) clade., Highlights • Plastomes from the genus Biophytum (Oxalidaceae) and the family Connaraceae are reported for the first time. • Little plastome variation was observed among genera of Oxalidaceae. • Several divergence hotspot regions were identified in the Oxalidaceae species. • The systematic position of Oxalidaceae was confirmed as sister to Connaraceae within Oxalidales.

Two methyl-modified Al2O3/SiO2 xerogels, i. e. AIP-Al2O3/MSiO2 and ANN-Al2O3/MSiO2 xerogels, were prepared using aluminum isopropoxide and aluminum nitrate nonahydrate as the aluminum precursors, respectively. The appearance, density, viscosity, Gibbs activation energy for viscous flow and reaction rate constant of the sols were analyzed and compared. Their microstructures were characterized by means of powder X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and nitrogen adsorption–desorption measurements. The results show that the Al–O–Si bond is formed in the AIP-Al2O3/MSiO2 and ANN-Al2O3/MSiO2 xerogels. The ANN-Al2O3/MSiO2 sol has a smaller mean particle size and greater sol stability than the AIP-Al2O3/MSiO2 sol. Meanwhile, the ANN-Al2O3/MSiO2 xerogel has a smaller pore size and higher porosity. The total pore volume and specific surface area of the ANN-Al2O3/MSiO2 xerogel are 27.27% and 29.36% larger than those of the AIP-Al2O3/ MSiO2 sample, respectively. The saturated adsorption capacity of the ANN-Al2O3/MSiO2 xerogel to methylene blue is 7.15% larger than that of the AIP-Al2O3/MSiO2 xerogel.

With methyltriethoxysilane as hydrophobic precursors and aluminum isopropoxide as the aluminum source, the Al2O3/SiO2 sols and their gel materials were prepared. The effects of aluminum content (nA...

Titanium dioxide (TiO2) sol was prepared using tetrabutyl titanate as a precursor via an acid catalyzed sol-gel process. Investigation of the effects of acid content and annealing on the properties...

A series of Al2O3 sols were prepared by HNO3 catalysis of aluminum isopropoxide (AIP), using different molar ratios of HNO3/AIP (nH). The changes in sol densities, viscosities, refractive i...

Highlights • NbSe2 micro/nanoparticles were achieved by ultrasonic-assisted exfoliation. • Prolonged ageing process modifies the morphology and chemical composition. • The excellent lubricating property with low friction coefficient and longer lifetime is obtained., 2H-NbSe2 single crystal flake (ca. 2 × 2 × 0.5 mm in size) by chemical vapor transport is employed as the precursor for a top-down preparation of NbSe2 micro/nanoparticles by two kinds of processes, i.e. (1) mechanical exfoliation; (2) ultrasonic-assisted exfoliation in ethanol without ageing and with ageing for 210 days. NbSe2 micro/nanoparticles are applied on top of a Cu disk by a drop-casting process and the tribological property in sliding against a Cu pin under sliding electrical contact is investigated at room temperature. Mechanical exfoliation produces NbSe2 microplatets with typical sizes of 1 μm to 30 μ m with a thickness less than 2 μm. Ultrasonic-assisted exfoliation without aging facilitates the formation of NbSe2 micro/nanoplatets with sizes of 0.1 μm to 25 μm and nano-whiskers with 100 nm in diameter and 1 ~ 3 μm in length, but Nb2O5 and Se are also found on the basis of XPS results. Prolonged aging of the suspensions modifies the morphology by converting platets and whiskers into corrugated floccules (hybrid material), which are composed of Nb2O5, Se, NbSe2, and graphene. Notably, NbSe2 micro/nanoparticles by ultrasonic-assisted exfoliation without ageing exhibit an excellent lubricating property with low friction coefficient (0.3), mild wear, and longer wear lifetime (120 min) than that of mechanical exfoliated NbSe2 microplatets (10 min). The wear lifetime for the aged NbSe2 micro/nanoparticles can be as long as 504 min and are 4.2 times of the sample without aging, which can be a good solid lubricant for sliding electrical contact

Oxalidaceae is one of the most important plant families in horticulture, and its key commercially relevant genus, Averrhoa, has diverse growth habits and fruit types. Here, we describe the assembly of a high-quality chromosome-scale genome sequence for Averrhoa carambola (star fruit). Ks distribution analysis showed that A. carambola underwent a whole-genome triplication event, i.e., the gamma event shared by most eudicots. Comparisons between A. carambola and other angiosperms also permitted the generation of Oxalidaceae gene annotations. We identified unique gene families and analyzed gene family expansion and contraction. This analysis revealed significant changes in MADS-box gene family content, which might be related to the cauliflory of A. carambola. In addition, we identified and analyzed a total of 204 nucleotide-binding site, leucine-rich repeat receptor (NLR) genes and 58 WRKY genes in the genome, which may be related to the defense response. Our results provide insights into the origin, evolution and diversification of star fruit.

The Ag-loaded hydrophobic silica (Ag/M-SiO2) materials were prepared by sol-gel method with tetraethylorthosilicate (TEOS) as precursor and methyltriethoxysilane (MTES) as hydrophobic modifier. Contact angles, X-ray diffraction and X-ray photoelectron spectra were used to characterize the as-prepared Ag/M-SiO2 materials. The antibacterial properties of the Ag/M-SiO2 materials were evaluated against Escherichia coli and Staphylococcus aureus. The results indicated that the appropriate calcination temperature of keeping the hydrophobicity of Ag/M-SiO2 materials is 300∼500°C. Ag element exists in Ag/M-SiO2 materials as the elemental form and hydrophobic Si-CH3 groups have been successfully introduced into the Ag/M-SiO2 materials. The qualitative and quantitative antibacterial experiments showed that the antibacterial activity increased with the increase of silver content. When the molar ratio of Ag/TEOS is increased to 0.10, the Ag/M-SiO2 materials showed good antibacterial dissolution and broad-spec...

The batch reaction experiments have been made for the first time to investigate the effect of ionic structure on the reactivity and selectivity of the trioxane-forming reaction catalyzed by a Bronsted-acidic ionic liquid (IL). The ILs considered include 1-cyclohexyl-2-pyrrolidinonium trifluoromethanesulfonate ([NCyP][TfO]), 1-cyclohexyl-2-pyrrolidinonium benzenesulfonate ([NCyP][BSA]), 1-cyclohexyl-2-pyrrolidinonium p -toluenesulfonate ([NCyP][ p -TSA]), 1-octyl-2-pyrrolidinonium 2,4-dinitrobenzenesulfonate ([NOP][DNBSA]), 1-octyl-2-pyrrolidinonium benzenesulfonate ([NOP][BSA]), 1-octyl-2-pyrrolidinonium methanesulfonate ([NOP][MSA]), and 1-octyl-2-pyrrolidinonium trifluoromethanesulfonate ([NOP][TfO]). It is found that the yield of trioxane in the reaction solution correlates inversely with the Hammett acidity function H 0 of the aqueous solution of the corresponding ILs. Variation of the cation structure from [NCyP] + to [NOP] + exerts little influence on the yield and the selectivity of trioxane in the reaction solution. Using [TfO] − or [DNBSA] − in place of [MSA] − or [BSA] − apparently increases the yield of trioxane, but only slightly increases the concentration of formic acid in the reaction solution. The continuous production experiments have been made to investigate the performance of [NOP][MSA], [NOP][DNBSA], [NCyP][TfO], and H 2 SO 4 as an extraction distillation agent. Such effect of [NCyP][TfO] considerably overrides that of H 2 SO 4 . The yield and the selectivity of trioxane are both increased when [NCyP][TfO] is used instead of H 2 SO 4 at a reaction time 5 h.

The densities and viscosities are measured in the temperature range (293.15 to 308.15) K and atmospheric pressure for the ternary systems [NMP][MSA] (1-methyl-2-pyrrolidinonium methanesulfonate) + LaCl3 (lanthanum chloride) + H2O, [NMP][BSA] (1-methyl-2-pyrrolidinonium benzenesulfonate) + LaCl3 + H2O, and [NMP][p-TSA] (1-methyl-2-pyrrolidinonium p-toluenesulfonate) + LaCl3 + H2O and their binary subsystems LaCl3 + H2O, [NMP][MSA] + H2O, [NMP][BSA] + H2O, and [NMP][p-TSA] + H2O. The densities and viscosities of the ternary systems are estimated using the literature equations and the corresponding properties of their binary subsystems. The comparisons of the predicted and the measured results are made.