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Abstract [Objective] We aim to investigate the morphological adaptation characteristics of peony in different habitats to the environment in the plain areas, and to provide references for peony conservation research and screening of high-quality germplasm resources. [Methods] The Central Plain peonies (Paeonia ostii ‘Fengdan’ and P .‘Luoyanghong’) and wild peonies (P . delavayi Franch, P . potanini, P . ludlowii, P . lutea (Tibet), P . lutea and P . qiui) were used as materials, and paraffin section technique was used to observe the leaf structure and analyze the related indexes. [Results] (1) The leaf epidermal morphology of the Central Plain peonies and wild peonies showed varying degrees of variation. The leaves were heterofacial, with the upper and lower epidermal cells were irregularly shaped, and the stomata was uniformly distributed in the lower epidermis. (2) The leaves and cuticles of P . ludlowii were thin. The palisade tissue was underdeveloped. The intercellular space was large and the stomatal density was high. The thickness of leaves, palisade tissue, and sponge tissue of P . lutea was the largest. (3) Stomatal density and epidermal thickness, chlorophyll b and chlorophyll a/b, total chlorophyll and chlorophyll a/b were significantly negatively correlated (P

As a plant-specific gene family, class III peroxidases (PODs) play an important role in plant growth, development, and stress responses. However, the POD gene family has not been systematically studied in Paeonia ostii. In this study, a total of 57 PoPOD genes were identified in the P. ostii genome. Subsequently, phylogenetic analysis and chromosome mapping revealed that PoPODs were classified into six subgroups and were unevenly distributed across five chromosomes. The gene structure and conserved motifs indicated the potential for functional divergence among the different subgroups. Meanwhile, four PoPODs were identified as tandem duplicated genes, with no evidence of segmental duplication. Using RNA-seq data from eight different tissues, multiple PoPODs exhibited enhanced expression in apical and adventitious roots (ARs). Next, RNA-seq data from AR development combined with trend analysis showed that PoPOD30/34/43/46/47/57 are implicated in the formation of ARs in tree peony. Through WGCNA based on RNA-seq, two key genes, PoPOD5/15, might be involved in heat tolerance via ABA and MeJA signaling. In addition, real-time quantitative PCR (qRT-PCR) analysis indicated that PoPOD23 may play an important role in flower senescence. These findings deepened our understanding of POD-mediated AR development, heat tolerance, and petal senescence in tree peony. [ABSTRACT FROM AUTHOR]

SERK is a marker gene for early somatic embryogenesis. We screened and functionally verified a SERK-interacting protein to gain insights into tree-peony somatic embryogenesis. Using PoSERK as bait, we identified PorbcL (i.e., the large subunit of Rubisco) as a SERK-interacting protein from a yeast two-hybrid (Y2H) library of cDNA from developing tree-peony somatic embryos. The interaction between PorbcL and PoSERK was verified by Y2H and bimolecular fluorescence complementation analyses. PorbcL encodes a 586-amino-acid acidic non-secreted hydrophobic non-transmembrane protein that is mainly localized in the chloroplast and plasma membrane. PorbcL was highly expressed in tree-peony roots and flowers and was up-regulated during zygotic embryo development. PorbcL overexpression caused the up-regulation of PoSERK (encoding somatic embryogenesis receptor-like kinase), PoAGL15 (encoding agamous-like 15), and PoGPT1 (encoding glucose-6-phosphate translocator), while it caused the down-regulation of PoLEC1 (encoding leafy cotyledon 1) in tree-peony callus. PorbcL overexpression led to increased indole-3-acetic acid (IAA) content but decreasing contents of abscisic acid (ABA) and 6-benzyladenosine (BAPR). The changes in gene expression, high IAA levels, and increased ratio of IAA to ABA, BAPR, 1-Aminocyclopropanecarboxylic acid (ACC), 5-Deoxystrigol (5DS), and brassinolide (BL) promoted embryogenesis. These results provide a foundation for establishing a tree-peony embryogenic callus system. [ABSTRACT FROM AUTHOR]

This study investigates the control mechanism of blasting damage to surrounding rock and conducts a quantitative evaluation of the damage using laboratory experimentation and field test. A comprehensive evaluation system of blasting damage for roadway contour quality and internal damage of surrounding rock is established using digital image processing, multifractal spectrum calculation, CT scanning, borehole televiewer, and acoustic testing. The results show that the evolution of blasting damage conforms with fractal law, and the relationship between blasting damage area and fractal dimension follows a power function. Slit charge blasting causes the initiation and propagation of two straight main cracks along the slit. The peak velocity measured at the center of the slit charge is found to be 1.74 times that of the ordinary charge. The slit charge can effectively reduce the blasting damage. [ABSTRACT FROM AUTHOR]

Tree peony (Paeonia suffruticosa Andr.) is a woody plant with high ornamental, medicinal, and oil values. However, its low rooting rate and poor rooting quality are bottleneck issues in the micropropagation of P. ostii. The WUSCHEL-related homeobox (WOX) family plays a crucial role in root development. In this study, based on the screening of the genome and root transcriptome database, we identified ten WOX members in P. ostii. Phylogenetic analysis revealed that the ten PoWOX proteins clustered into three major clades, the WUS, intermediate, and ancient clade, respectively. The conserved motifs and tertiary structures of PoWOX proteins located in the same clade exhibited higher similarity. The analysis of cis-regulatory elements in the promoter indicated that PoWOX genes are involved in plant growth and development, phytohormones, and stress responses. The expression analysis revealed that PoWOX genes are expressed in distinct tissues. PoWOX4, PoWOX5, PoWOX11, and PoWOX13b are preferentially expressed in roots at the early stage of root primordium formation, suggesting their role in the initiation and development of roots. These results will provide a comprehensive reference for the evolution and potential function of the WOX family and offer guidance for further study on the root development of tree peony. [ABSTRACT FROM AUTHOR]

Rapid wilting after harvest greatly decreases the ornamental and economic value of fresh-cut flowers. To determine how chlorine dioxide (ClO2) affects postharvest flower quality, Paeonia lactiflora 'Hushui Dangxia' cut flowers in bottles were treated with different concentrations of ClO2 (0, 25, 50, 75, and 100 mg L−1). Among the treatments, ClO2 75 (i.e., 75 mg L−1) decreased the bacterial growth and lignin content at the P. lactiflora flower stem base, while also decreasing the degree of flower stem vessel blockage. Additionally, the ClO2 75 treatment increased the relative fresh weight, water balance, soluble sugar content, soluble protein content, and antioxidant enzyme activities (superoxide dismutase, peroxidase, and catalase), but decreased the malondialdehyde content and ethylene release rate of P. lactiflora cut flowers. Thus, the aging of P. lactiflora flowers was delayed, thereby maintaining the cut flower quality. Furthermore, the vase life (i.e., ornamental period) increased by three days. [ABSTRACT FROM AUTHOR]

Blockchain is a revolutionary technology that has reshaped the trust model among mutually distrustful peers in a distributed network. While blockchain is well-known for its initial usage in a public manner, such as the cryptocurrency of Bitcoin, consortium blockchain, which requires authentication of all involved participants, has also been widely adopted in various domains. Nevertheless, there is a lack of comprehensive study of consortium blockchain in terms of its architecture design, consensus mechanisms, comparative performance, etc. In this study, we aim to fill this gap by surveying the most popular consortium blockchain platforms and assessing their core designs in a layered fashion. Particularly, Byzantine fault tolerant (BFT) state machine replication (SMR) is introduced to act as a basic computational model of consortium blockchain. Then the consortium blockchain is split into the hardware layer, layer-0 (network layer), layer-I (data layer, consensus layer and contract layer), layer-II protocols, and application layer. Each layer is presented with closely related discussion and analysis. Furthermore, with the extraction of the core functionalities, i.e., robust storage and guaranteed execution, that a consortium blockchain can provide, several typical consortium blockchain-empowered decentralized application scenarios are introduced. With these thorough studies and analyses, this work aims to systematize the knowledge dispersed in the consortium blockchain, highlight the unsolved challenges, and also indicate the propitious avenues of future work. [ABSTRACT FROM AUTHOR]

According to the traditional blasting theory and practice, the slotted cartridge blasting can form straight cracks extending along the slot direction and achieve directional fracture. In this paper, an experimental study has been carried out to determine the influence of incident stress waves and reflected stress waves. Under the influence of stress waves, the propagation path of the main crack in slotted cartridge blasting is not straight, and the directional fracture effect is inadequate. Under the experimental conditions in this paper, the propagation of main cracks mainly experienced three stages: directional propagation stage, counterclockwise deflecting propagation stage, and clockwise deflecting propagation stage. The difference between incident stress waves and reflected stress waves results in the difference in the deflecting direction, transforming the main crack into a wing shape. In rock roadway drilling and blasting engineering, the propagation path of main cracks produced by peripheral boreholes using the slotted cartridge blasting is also affected by the incident and reflected stress waves. These stress waves are inevitably generated from free faces and adjacent boreholes; however, these are rarely considered in the design of blasting parameters. Therefore, the design and optimization of blasting parameters considering the interaction of stress waves and main cracks in the slotted cartridge blasting need to be further developed. [ABSTRACT FROM AUTHOR]