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The Asteraceae are widely distributed throughout the world, with diverse functions and large genomes. Many of these genes remain undiscovered and unstudied. In this study, we discovered a new gene ClNUM1 in Chrysanthemum lavandulifolium and studied its function. In this study, bioinformatics, RT-qPCR, paraffin sectioning, and tobacco transgenics were utilized to bioinformatically analyze and functionally study the three variable splice variants of the unknown gene ClNUM1 cloned from C. lavandulifolium. The results showed that ClNUM1.1 and ClNUM1.2 had selective 3′ splicing and selective 5′ splicing, and ClNUM1.3 had selective 5′ splicing. When the corresponding transgenic tobacco plants were subjected to abiotic stress treatment, in the tobacco seedlings, the ClNUM1.1 gene and the ClNUM1.2 gene enhanced salt and low-temperature tolerance and the ClNUM1.3 gene enhanced low-temperature tolerance; in mature tobacco plants, the ClNUM1.1 gene was able to enhance salt and low-temperature tolerance, and the ClNUM1.2 and ClNUM1.3 genes were able to enhance low-temperature tolerance. In summary, there are differences in the functions of the different splice variants and the different seedling stages of transgenic tobacco, but all of them enhanced the resistance of tobacco to a certain extent. The analysis and functional characterization of the ClNUM1 gene provided new potential genes and research directions for abiotic resistance breeding in Chrysanthemum.

Flowering cherry (Cerasus sp.) are significant spring-blooming trees. However, the short blooming period and the rarity of early and late-flowering varieties limit their use in gardens in northern China. The experiment incorporated annually early-flowering species such as Cerasus discoidea, Cerasus pseudocerasus ‘Introtsa’, Cerasus dielsiana, Cerasus campanulata ‘Youkou’, Cerasus yedoensis ‘Somei-Yoshino’, and Cerasus spachiana f. ascendens, as well as twice-a-year flowering species like Cerasus subhirtella ‘Autumnalis’ and Cerasus subhirtella ‘Accolade’. We observed the timing of natural events and growth measurements for specific plants over a span of two years. This research involved a thorough examination of their ability to withstand cold temperatures, considering their physiological aspects. We examined the levels of nutrients and hormones in the flower buds at various stages of development in plants that bloom yearly and every two years. The findings indicated that C. subhirtella ‘Autumnalis’ is adaptable, offering the lengthiest autumn blooming phase lasting 54 days. The hierarchy of cold tolerance was as follows: C. pseudocerasus ‘Introtsa’ > C. discoidea > Cerasus × subhirtella ‘Autumnalis’ > C. dielsiana > C. ‘Youkou’. Furthermore, the soluble protein content in leaves increased before autumn flower buds’ sprout of twice-a-year flowering varieties but declined in C. yedoensis ‘Somei-Yoshino’ within the same time. We determined that changes in nutrient content significantly contribute to the autumn opening of C. subhirtella ‘Autumnalis’ robust short branch flower buds. During the final phase of flower bud development, the rise in trans-Zeatin-riboside (ZR) and indolacetic acid (IAA) promotes the initiation of the first flowering period in C. subhirtella ‘Autumnalis’ prior to its mandatory hibernation. The occurrence of secondary flowering involves a multifaceted regulatory process. These findings serve as valuable references for delving deeper into the mechanisms governing cherry blossom formation and secondary flowering.

Ajania purpurea is a small semi-shrub in the Asteraceae family. Its corolla is purplish red from the middle to the top, and its leaves and flowers are all fragrant. It can be introduced and cultivated as ornamental plants. In order to survive adversity, plants actively regulate the expression of stress response genes and transcripts. Alternative splicing is a common phenomenon and an important regulation mode of eukaryotic gene transcription, which plays an important role in various biological processes. In this study, four splice variants of the NST1 gene were identified from A. purpurea, and the molecular mechanism of NST1 alternative splice variants involved in abiotic stress was explored through bioinformatics, transgenics and paraffin sectionalization. The analysis of amino acid sequences showed that ApNST1.1 had alternative 5′splicing, ApNST1.2 had alternative 3′splicing and ApNST1 had the two splicing types. The main conclusions from studying transgenic tobacco seedlings and adult seedlings under abiotic stress were as follows: ApNST1, ApNST1.1 and ApNST1.3 showed salt tolerance at seedling stage, especially ApNST1.3. At the mature seedling stage, the stem height of ApNST1.1 increased significantly, and ApNST1.1 showed obvious salt tolerance, while ApNST1.2 showed obvious cold resistance. Compared to Super35S::GFP, the xylem of ApNST1 thickened by 94 μm, and the cell wall thickened by 0.215 μm. These results are of great significance to the breeding and application of ApNST1 to select splice variants with more resistance to abiotic stress, and to future study in this area. At the same time, they provide a new direction for A. purpurea breeding, and increase the possibility of garden applications.

Leucanthemella linearis is a marsh plant in the family Compositae. It has good water and moisture resistance and ornamental properties, which makes it one of the important materials for chrysanthemum breeding and genetic improvement. The NST1 (NAC secondary wall enhancement factor 1) gene is associated with the thickening of the secondary walls of fiber cells in the plant ducts and the secondary xylem and plays an important role in plant stress resistance. In this study, two variable spliceosomes of the NST1 gene were identified from a chrysanthemum plant by using bioinformatics, qRT-PCR, transgene, and paraffin section methods to explore the molecular mechanism of the variable splicing of NST1 under abiotic stress. The results show that only three amino acids were found to be different between the two LlNST1 variants. After being treated with salt, drought, and low temperatures, analysis of the expression levels of the LlNST1 and LlNST1.1 genes in Ll showed that LlNST1.1 could respond to low temperatures and salt stress and had a weak response to drought stress. However, the expression level of LlNST1 under the three treatments was lower than that of LlNST1.1. LlNST1 transgenic tobacco showed increased saline–alkali resistance and low-temperature resistance at the seedling stage. LlNST1.1 transgenic tobacco also showed enhanced saline–alkali resistance and drought resistance at the seedling stage. In conclusion, the functions of the two variable spliceosomes of the NST1 gene are very different under abiotic stress. Therefore, this study verified the function of the variable spliceosome of NST1 and improved the stress resistance of the chrysanthemum plant under examination by regulating the expression of the NST protein, which lays a material foundation for the improvement of plant stress resistance materials and has important significance for the study of the resistance of chrysanthemum plants to abiotic stress.

In the optical system for reconstructing speech signals based on laser speckle images, the resonance between the sound source and nearby objects leads to frequency response problem, which seriously affects the accuracy of reconstructed speech. In this paper, we propose a speech enhancement algorithm to reduce the frequency response. The results show that after using the speech enhancement algorithm, the frequency spectrum correlation coefficient between the reconstructed sinusoidal signal and the original sinusoidal signal is improved by up to 82.45%, and the real speech signal is improved by up to 56.40%. This proves that the speech enhancement algorithm is a valuable tool for solving the frequency response problem and improving the accuracy of reconstructed speech.

[Objective] Cloning of the AtrMYB transcription factor gene from Acer truncatum was conducted to further explore the red leaf development mechanism and breed cultivars of colored - leaf maple. [Method] The Acer truncatum 'Luhorig No.1' cuitivar was used as the material for cloning the MYB gene by mean of RTPCR and RACE-PCR. [Results] Sequence analysis showed that the fragment contained a full coding region of 831 bp encoding 276 amino acid residues with a molecular weight of 32.17kD and a molecular formula C14aoH14052N2247O4o6S14. The gene was named as AtrMYB with a GenBank accession number of 1825712. This coded protein had a pi of 9.44. The results showed that the AtrMYB exhibited typical features of the R2R3-MYB domain. The AtrMYB was highly homologous with the MYB of other species at nucleotide and amino acid levels. The AtrMYB had no signal peptide, but a nuclear localization signal. The phylogenetic tree showed that the AtrMYB was at the same clade as the MYB from Citrus sinensis. [Conclusion] The AtrMYB was cloned from Acer truncatum 'Luhong No.1 ‘ cuitivar. These results have provided a foundation for further purification and identification of target protein and function study of the AtrMYB. [ABSTRACT FROM AUTHOR]

Leaves of Acer truncatum 'Luhong No. 1' contain large amounts of polysaccharides and polyphenols, which seriously affect extraction yield and quality of total RNA. In order to explore the appropriate total RNA extraction method, total RNA was extracted from leaves of A. truncatum 'Luhong No. 1' with three methods, including kit method, Trizol method and modified CTAB method. The results showed that OD260/OD280 and OD260/OZ230 ratios of total RNA extracted from leaves of A. truncatum 'Luhong No. 1' with kit method were higher than 1. 8, with a general yield and certain level of DNA contamination; OD260/OD280 and OD260/OD230 ratios of total RNA extracted with Trizol method were about 1.5, with the lowest yield; OD260/OD280 and OD260/OD230 ratios of total RNA extracted with modified CTAB method were about 2.0, with the highest yield and distinct electrophoresis patterns. The results demonstrated that total RNA extracted with modified CTAB method exhibited high yield and purity, which could meet the demands of subsequent molecular biology research. Thus, modified CTAB method is the appropriate method for extracting total RNA from leaves of A. truncatum 'Luhong No. 1'. [ABSTRACT FROM AUTHOR]