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[Objective] This paper aims to investigate the characteristics of Primulina guizhongensis pollen and the influence of the breeding system on its sexual reproduction, to uncover its reproduction mechanism and providing theoretical references for the conservation and development of Primulina. [Methods] Using P . guizhongensis as the material, we observed the floral characteristics of P . guizhongensis, screened the pollen isolation medium and the best pollen viability detection method, explored optimal pollen storage conditions, as well as determined the type of its breeding system. [Results] (1) P . guizhongensis was dichogamy, with stamens ripening before pistils. It was herkogamy, with pistils higher than stamens. (2) The optimum medium for culture of the isolated pollen germination was 40 mg/mL boric acid + 10% sucrose + 7 g/L agar, for two hours. (3) Pollen maintained a high germination rate after 7 d of storage at both -20 ℃ and -80 ℃. (4) The stigmas of P . guizhongensis were most fertile at 2-4 d of flowering. (5) P/O was 518.36-782.75, and OCI was 5. (6) P . guizhongensis had a high self-fertilization affinity and was unable to undergo fusionless reproduction. [Conclusion] In vitro germination method is the most intuitive and accurate way to detect pollen viability. Low temperature is conducive to pollen storage of P . guizhongensis, and the breeding system is predominantly heterogametic.

Coating GFRP bars with a layer of carbon fibers containing carbon/glass-hybrid-fiber-reinforced polymer (HFRP) bars has been proven to improved interlaminar shear durability. Thus, the bond performance of the HFRP bar-concrete interface depends on the behavior of the HFRP-reinforced concrete structure. In this context, the study investigates the effects of the compressive strength of concrete and the embedded length of HFRP bars on the bond behavior of the HFRP bar-concrete interface and compares the results with the data on the interfacial bond of GFRP bar to concrete. The results demonstrate that all the specimens fail at the FRP bar–concrete interface under the pullout. The bond strength and bond stiffness of the HFRP bar–concrete composites decrease with an increase in the embedded length of the HFRP bar from 4 to 10 times its diameter. Raising the compressive strength of the concrete enlarges the bond strength and bond stiffness of the HFRP bar–concrete composites. Furthermore, the outer layer of carbon-fiber on the GFRP bar decreases the impact of the embedded length of the HFRP bar on the bond strength and bond stiffness of the HFRP bar–concrete composites. Finally, the improved modified mBPE model can accurately predict the bond stress–slip relationship of GFRP/BFRP/HFRP bar–concrete composites. [ABSTRACT FROM AUTHOR]

The MYB gene family is significant in plants, playing a role in numerous plant development processes, including metabolism, hormone signal transduction, cell identity, and biotic and abiotic stresses. Due to the recent availability of the Melastoma candidum genome, this is the first time that the MYB gene family has been identified in this species. This study identified 421 MYB gene members in the M. candidum genome using the HMMER search and BLASTp method. These MYBs were further divided into 10 sub-types, including R2R3, R-R, CPC-like, CCA1-like, TBP-like, R1R2R3, I-box, atypical MYB, MYB-CC, and MYB-like. Domain and conservation analyses revealed that each type of MYB was characterized by a different number and combination of SANTs/myb DNA-binding domains. Collinearity analysis revealed several gene duplication events within the MYB gene family. The Ka to Ks ratio suggested that most of the MYB genes underwent purifying selection during the evolution process. Phylogenetic analysis among three species confirmed our findings and displayed the evolutionary relationship of MYB genes in different species. RNA-seq of three developmental stages of flowers and WGCNA analysis identified McMYB113h, McMYB21b, and McGLK1c as playing a pivotal role during flower development in M. candidum. Finally, we conducted qRT-PCR experiments for 20 flower-development-related MYBs across 9 tissues to illustrate their expression patterns in M. candidum. This study establishes a foundation for exploring MYB gene resources and their potential applications in related industries of M. candidum. [ABSTRACT FROM AUTHOR]

Epoxy coatings provide an economical and practical solution for combating steel corrosion. However, epoxy coatings have poor conductivity, resulting in the accumulation of electrostatic charges. The surface conductivity and anticorrosion properties of epoxy coatings can be improved by adding nano-Cu and hydroxylated multi-walled carbon nanotubes (MWCNTs). This paper investigates the impact of MWCNTs at different concentrations (2.5, 5%) and the ratio of nano-Cu to MWCNTs on the surface conductivity and anticorrosion properties of epoxy coatings on a steel substrate. The findings from the four-probe method of measuring surface resistance indicated that the surface resistivity of steel coated with an epoxy composite of 5% MWCNTs and 65% nano-Cu (Cu65/MWCNT5) was significantly lower, approximately by one order of magnitude, compared to steel coated with a 5% MWCNT (MWCNT5) epoxy coating. When the Cu65/MWCNT5-coated steel was immersed in a 3.5 wt % NaCl solution for 30 days, it was observed that there was a minimal effect on its surface resistivity. The inclusion of a high content of MWCNTs facilitates a more uniform distribution of Cu particles within the epoxy coatings, thereby improving the anticorrosion properties of these coatings on a steel substrate. This was further corroborated by the results of the polarization curves and electrochemical impedance spectroscopy, demonstrating that the Cu65/MWCNT5 epoxy coating on a steel substrate offers exceptional anticorrosion and barrier protection properties. The corrosion rate of steel with a Cu65/MWCNT5 epoxy coating was three orders of magnitude lower than that of steel with a Cu65/MWCNT2.5 epoxy coating, at 4.79 × 10−7 mm/year. [ABSTRACT FROM AUTHOR]

Plants biosynthesize secondary metabolites that can be useful in various applications, including health promotion, thanks to their organoleptic properties and antioxidant activity. Abbas, O'Neill Rothenberg, et al. ([5]) reviewed the diverse role of plant VOCs, including plant defenses, attracting pollinators, and mediating various interactions between plants and their environment. Aphids use VOC emissions from plants to locate their host plant, but plants can use the same signaling mechanism to entice parasitic wasps as an indirect defense system. 30 Wang, D., Chen, L., Yang, Y., Abbas, F., Qin, Y., Lu, H. et al. (2023) Integrated metabolome and transcriptome analysis reveals the cause of anthocyanin biosynthesis deficiency in litchi aril. [Extracted from the article]

N 1 -methyladenosine is a unique type of base methylation in that it blocks Watson-Crick base pairing and introduces a positive charge. m 1 A is prevalent in yeast and mammalian mRNA and plays a functional role. However, little is known about the abundance, dynamics, and topology of this modification in plant mRNA. Dot blotting and liquid chromatography tandem mass spectrometry analyses revealed a dynamic pattern of m 1 A mRNA modification in various tissues and at different developmental stages in petunia ( Petunia hybrida ), a model system for plant growth and development. We performed transcriptome-wide profiling of m 1 A in petunia mRNA by m 1 A mRNA immunoprecipitation followed by a deep-sequencing approach (m 1 A-seq, using an m 1 A-specific antibody). m 1 A-seq analysis identified 4,993 m 1 A peaks in 3,231 genes expressed in petunia corollas; there were 251 m 1 A peaks in which A residues were partly replaced by thymine and/or reverse transcription stopped at an adenine site. m 1 A was enriched in coding sequences, with single peaks located immediately after start codons. Ethylene treatment upregulated 400 m 1 A peaks in 375 mRNAs and downregulated 603 m 1 A peaks in 530 mRNAs in petunia corollas; 975 m 1 A peaks in mRNA were only detected in corollas treated with air and 430 were only detected in corollas treated with ethylene. Silencing of petunia tRNA-specific methyltransferase 61A ( PhTRMT61A ) reduced the m 1 A level in mRNA in vivo and in vitro. In addition, PhTRMT61A silencing caused abnormal leaf development, and the PhTRMT61A protein was localized to the nucleus. Thus, m 1 A in mRNA is an important epitranscriptome marker and plays a role in plant growth and development., (© 2020 American Society of Plant Biologists. All Rights Reserved.)