Rosaceae Species Research Articles

PbRbohH/J mediates ROS generation to regulate the growth of pollen tube in pear

Respiratory burst oxidase homolog (Rboh) family genes play crucial functions in development and growth. However, comprehensive and systematic investigation of Rboh family members in Rosaceae and their specific functions during pear pollen development are still limited. In the study, 63 Rboh genes were identified from eight Rosaceae genomes (Malus domestica, Pyrus bretschneideri, Pyrus communis, Prunus persica, Rubus occidentalis, Fragaria vesca, Prunus mume and Prunus avium) and divided into seven main subfamilies (I-VII) according to phylogenetic and structural features. Different modes of gene duplication led to the expansion of Rboh family, with purifying selection playing a vital role in the evolution of Rboh genes. In addition, RNA sequencing and qRT-PCR results indicated that PbRbohH and PbRbohJ were specifically high-expressed in pear pollen. Subsequently, subcellular localization revealed that PbRbohH/J distributed at the plasma membrane. Furthermore, by pharmacological analysis and antisense oligodeoxynucleotide assay, PbRbohH/J were demonstrated to mediate the formation of reactive oxygen species (ROS) to manage pollen tube growth. In conclusion, our results provide useful insights into the functions, expression patterns, evolutionary history of the Rboh genes in pear and other Rosaceae species.

Identification and Biological Characteristics of Mortierella alpina Associated with Chinese Flowering Cherry (Cerasus serrulata) Leaf Blight in China.

The Chinese flowering cherry (Cerasus serrulata), an ornamental tree with established medicinal values, is observed to suffer from leaf blight within Xi'an's greenbelts. This disease threatens both the plant's growth and its ornamental appeal. In this study, 26 isolates were obtained from plants with typical leaf blight, and only 3 isolates (XA-10, XA-15, and XA-18) were found to be pathogenic, causing similar symptoms on the leaves of the host plant. Based on sequence alignment, the ITS and LSU sequences of the three selected isolates were consistent, respectively. Following morphological and molecular analyses, the three selected isolates were further identified as Mortierella alpina. The three selected isolates exhibited similar morphological characteristics, including wavy colonies with dense, milky-white aerial mycelia on PDA medium. Therefore, isolate XA-10 was used as a representative strain for subsequent experiments. The representative strain XA-10 was found to exhibit optimal growth at a temperature of 30 °C and a pH of 7.0. Host range infection tests further revealed that the representative strain XA-10 could also inflict comparable disease symptoms on both the leaves and fruits of three different Rosaceae species (Prunus persica, Pyrus bretschneideri, and Prunus salicina). This study reveals, for the first time, the causative agent of leaf blight disease affecting the Chinese flowering cherry. This provides a deeper understanding of the biology and etiology of M. alpina. This study lays a solid foundation for the sustainable control and management of leaf blight disease in the Chinese flowering cherry.

Genome-wide identification and characterization of the Lateral Organ Boundaries Domain (LBD) gene family in nine Rosaceae species and expression pattern in <i>Prunus mume</i>

Genome-wide identification and characterization of the Lateral Organ Boundaries Domain (LBD) gene family in nine Rosaceae species and expression pattern in <i>Prunus mume</i>

An improved and effective DNA extraction protocol for Pyracantha crenulata with optimal PCR reliability

Abstract There are many challenges involved in obtaining high-quality DNA from tissues/cells, especially when using plants as the raw material. Three different DNA extraction protocols were employed in order to isolate high quality of genomic DNA from Pyracantha crenulata leaves. P. crenulata is a complex, versatile, and evergreen shrub species in Rosaceae family which is ecologically, economically and culturally important. This species produces valuable antioxidants like polyphenols, polysaccharides and secondary metabolites which interfere with DNA extraction thus making molecular marker based studies difficult in this species. This study aimed to develop a simple, rapid, cost-effective and highly efficient protocol for P. crenulata leaves rich in salts and phenols. The results demonstrated that modified CTAB (double buffer) protocol is very effective in overcoming the challenges that could impede next-generation sequencing analysis. The yield of the extracted DNA was excellent ranging from 368 to 410 ng/μL DNA with A260/280 ratio ranging from 1.80 to 1.84. The extracted DNA was amenable to PCR amplification making it suitable for DNA-based molecular marker studies. None procedures have been published for the purpose up this species, therefore, double buffer based extraction protocol is reported for the first time in P. crenulata and might prove useful in other species of family Rosa-ceae. This study describes an effective DNA isolation method that is appropriate for frequent population genetic screening. In conclusion, the double buffer protocol showed the most efficient and effective approach for extracting DNA from phenol rich, fresh, mature, and dry leaves.

Genome-Wide Identification, Evolution, and Expression Analysis of the MAPK Gene Family in Rosaceae Plants

Mitogen-activated protein kinases (MAPKs) are crucial regulators in coping with abiotic and biotic stresses, including drought, salinity, fungi, and pathogens. However, little is known about the characteristics, evolution process, and functional divergence of the MAPK gene family in Rosaceae plants. A total of 97 MAPK members were identified in six Rosaceae species, including 12 genes in Fragaria vesca, 22 genes in Malus domestica, 23 genes in Pyrus bretschneideri, 12 genes in Prunus mume, 14 genes in Prunus persica, and 14 genes in Rosa chinensis. All MAPK members of six Rosaceae plants were categorized into four clusters by the phylogenetic relationship analysis. Collinearity analysis discovered that both segmental duplication and tandem duplication contributed to the expansion of MAPK family genes in Rosaceae plants. And the analysis of motifs and gene structures indicated that the evolution of the MAPK gene family was highly conserved among phylogenetic clusters in Rosaceae species. In addition, the dN/dS rates of MAPK paralogous gene pairs were below one, suggesting the MAPK gene family in Rosaceae was driven by purifying selective pressure. Furthermore, functional divergence analysis discovered that 14 amino acid residues were detected as potentially key sites for functional divergence of MAPK family genes between different cluster pairs, specifically Type I functional divergence. The analysis of functional distance indicated that cluster C retained more of the original functional features, while cluster B exhibited functional specialization. Moreover, the expression profiles revealed that PmMAPK8, PmMAPK9, and PmMAPK10 were both highly expressed under drought stress and low temperature conditions. This study aims to comprehensively analyze the evolutionary process and functional analyses of the MAPK gene family in Rosaceae plants, which will lay the foundation for future studies into MAPK genes of Rosaceae in response to drought and cold stress.

Comparative genomic analysis of the RabGAP gene family in seven Rosaceae species, and functional identification of PbrRabGAP10 in controlling pollen tube growth by mediating cellulose deposition in pear

Rab GTPase-activating proteins (RabGAPs), serving as crucial signaling switches, play essential roles in several physiological processes related to plant growth and development. However, despite their importance, information regarding the RabGAP gene family and their biological functions remains unknown in the Rosaceae. In this study, we identified a total of 127 RabGAP genes in seven Rosaceae species, which were divided into five subfamilies. Our findings indicate that whole genome duplication (WGD) events or dispersed duplication events largely contributed to the expansion of RabGAP family members within Rosaceae species. Through tissue-specific expression analyses, we revealed that the PbrRabGAP genes exhibited distinct expression patterns in different pear tissues. Furthermore, by examining the expression pattern during pollen development and employing an antisense oligonucleotide approach, we demonstrated that PbrRabGAP10, located in the cytoplasm, mediates the imbalance of cellulose distribution, thus regulating pollen tube elongation. In conclusion, the present study offers an overview of the RabGAP family in Rosaceae genomes and serves as the basis for further functional studies.

A new species of Cotoneaster (Rosaceae) from western Sichuan, China.

Cotoneasterdensiflorus, a new species of Rosaceae from western Sichuan, China, is described and illustrated. Morphologically, we inferred that the new species belongs to CotoneasterSer.Salicifolii sensu Yü et al. (1974) in the Flora of China and Fryer and Hylmö (2009). This species is most similar to C.salicifolius, but differs in its leaf blade of ovate-lanceolate to obovate shape (vs. elliptic-oblong to ovate-lanceolate), smaller length-width ratio of 2.37 ± 0.31 (vs. 3.17 ± 0.32), slightly conduplicate (vs. not conduplicate), less lateral veins of 6-8 pairs (vs. 12-16 pairs), upper surface slightly rugose (vs. rugose), leaf margin plane (vs. revolute), lower surface densely grey tomentose (vs. grey tomentose, with bloom), greater corolla diameter of 7-9 mm (vs. 5-6 mm), styles 2 (vs. 2-3), pyrenes 2 (vs. 2-3), larger pollen grains P/E values of 2.05 ± 0.12 (vs. 1.19 ± 0.05) and leaf epidermis type W (vs. type I). Based on phylogenetic analysis of the whole chloroplast genome, C.densiflorus is sister to C.rhytidophyllus, but distantly related to C.salicifolius.

Sequence Analysis of nrDNA ITS Region in Paşa and Şah Apple (Malus × domestica) Genotypes

In this study, phylogenetic analysis of Şah and Paşa apple genotypes was performed using nrDNA ITS sequences. After the plant leaves were brought to the laboratory, gDNAs were obtained by genomic DNA isolation method. PCR amplification was performed using primers ITS4 and ITS5A. ITS sequences of some apple and Rosaceae species were retrieved from NCBI, bioinformatics analyzes were made with Bioedit 7.2.3, Finch TV 1.4.0 and MEGA 6.0 programs and phylogenetic trees were constructed. In the study, ITS sequence length of the Paşa apple genotype was 656 bp, and the ITS sequence length of the Şah apple genotype was 649 bp. Only in the maximum likelihood phylogenetic tree constructed using sequences of apple genotypes, Paşa and Şah apple genotypes appeared in the same clade as Malus domestica cultivar="Casciana'' and Malus domestica cultivar="Rotella''. In the phylogenetic tree generated including other species belonging to the Rosaceae family; apple genotypes Pyrus, Cotoneaster, Crataegus, Sorbus, Eriobotrya and Prunus were detected in a same clade. Overall results clearly suggested that the ITS sequences were both suitable for differentiation between the selected genera and were compatible with previous phylogenetic studies.

Taxonomic delineation of two closely allied Rubus L. (Rosaceae) species with notes on the typification of the name R. fairholmianus

Rubus fairholmianus Gardner and R. micropetalus Gardner are the two closely allied taxa, collected from different localities of southern Western Ghats, India. Because of the absence of detailed description and the existence of morphological similarities, these taxa have been misidentified in many herbaria and other published floras. The present study discusses the major delineating features of both the taxa based on the conventional taxonomic studies and along with seed morphological analysis and also provides a note on the occurrence of R. moluccanus L. in Western Ghats. During the study, the name R. fairholmianus is also neotypified.

A High-Quality Reference Genome Assembly of Prinsepia uniflora (Rosaceae).

This study introduces a meticulously constructed genome assembly at the chromosome level for the Rosaceae family species Prinsepia uniflora, a traditional Chinese medicinal herb. The final assembly encompasses 1272.71 megabases (Mb) distributed across 16 pseudochromosomes, boasting contig and super-scaffold N50 values of 2.77 and 79.32 Mb, respectively. Annotated within this genome is a substantial 875.99 Mb of repetitive sequences, with transposable elements occupying 777.28 Mb, constituting 61.07% of the entire genome. Our predictive efforts identified 49,261 protein-coding genes within the repeat-masked assembly, with 45,256 (91.87%) having functional annotations, 5127 (10.41%) demonstrating tandem duplication, and 2373 (4.82%) classified as transcription factor genes. Additionally, our investigation unveiled 3080 non-coding RNAs spanning 0.51 Mb of the genome sequences. According to our evolutionary study, P. uniflora underwent recent whole-genome duplication following its separation from Prunus salicina. The presented reference-level genome assembly and annotation for P. uniflora will significantly facilitate the in-depth exploration of genomic information pertaining to this species, offering substantial utility in comparative genomics and evolutionary analyses involving Rosaceae species.

Universal PCR primers for identifying species of the genus Sanguisorba and other members of the family Rosaceae

Seven primers for the amplification of non-coding regions of chloroplast DNA via the polymerase chain reaction (PCR) have been designed. In order to find out whether these primers were universal, we used them in an attempt to amplify DNA fragments from various plant species of Rosaceae. Primers worked for species of the genus Sanguisorba and some species of the family Rosaceae. The fact that they amplify chloroplast DNA non-coding regions over a wide taxonomic range means that these primers may be used to study the population biology and evolution of plants.

Prunus quanzhouensis: a newly discovered species of Prunus subgen. Cerasus (Rosaceae) from northeastern Guangxi, China

Prunus quanzhouensis is a new species of Rosaceae discovered in Guangxi, China, which is here described and illustrated. Despite its morphological similarities to P. campanulata, P. conradinae and P. xueluoensis, it can be distinguished from them by being shrubs or small trees, with 1.5–3.0 m tall, leaves with 10–13 pairs of lateral veins, abaxially glabrous involucral bracts, adaxially appressed villous bracts, flowers measuring 1–1.2 cm in diameter, tubular hypanthium with about 9×3 mm, oblique sepals, 30–35 stamens, and a style that is villous and longer than the stamens. Less than six populations of this new species have been found in the type locality, with approximately 130 mature individuals, which accounted for more than 95% of the total population. Based on direct observation in the field and the IUCN Red List Categories and Criteria, P. quanzhouensis is classified as Endangered (EN).

Comparative genomics analysis provides insights into evolution and stress responses of Lhcb genes in Rosaceae fruit crops

BackgroundLight-harvesting chlorophyll a/b binding proteins (Lhcb) play crucial roles in plant growth, development, and the response to abiotic stress in higher plants. Previous studies have reported that Lhcb genes were involved in the phytochrome regulation and responded to different light and temperature conditions in Poaceae (such as maize). However, the evolution and functions of Lhcb genes remains poorly characterized in important Rosaceae species.ResultsIn this investigation, we conducted a genome-wide analysis and identified a total of 212 Lhcb genes across nine Rosaceae species. Specifically, we found 23 Lhcb genes in Fragaria vesca, 20 in Prunus armeniaca, 33 in Malus domestica ‘Gala’, 21 in Prunus persica, 33 in Rosa chinensis, 29 in Pyrus bretschneideri, 18 in Rubus occidentalis, 20 in Prunus mume, and 15 in Prunus salicina. Phylogenetic analysis revealed that the Lhcb gene family could be classified into seven major subfamilies, with members of each subfamily sharing similar conserved motifs. And, the functions of each subfamily was predicted based on the previous reports from other species. The Lhcb proteins were highly conserved within their respective subfamilies, suggesting similar functions. Interestingly, we observed similar peaks in Ks values (0.1–0.2) for Lhcb genes in apple and pear, indicating a recent whole genome duplication event (about 30 to 45 million years ago). Additionally, a few Lhcb genes underwent tandem duplication and were located across all chromosomes of nine species of Rosaceae. Furthermore, the analysis of the cis-acting elements in the 2000 bp promoter region upstream of the pear Lhcb gene revealed four main categories: light response correlation, stress response correlation, hormone response correlation, and plant growth. Quantitative expression analysis demonstrated that Lhcb genes exhibited tissue-specific expression patterns and responded differently to low-temperature stress in Rosaceae species.ConclusionsThese findings shed light on the evolution and phylogeny of Lhcb genes in Rosaceae and highlight the critical role of Lhcb in pear’s response to low temperatures. The results obtained provide valuable insights for further investigations into the functions of Lhcb genes in Rosaceae, and these functional genes will be used for further fruit tree breeding and improvement to cope with the current climate changes.

Study on selection of woody plants to create sustainable green spaces in sparsely forested rural areas

For sustainable development of rural areas in low forested regions it is necessary to create additional areas of artificial plantations from the adapted gene pool of woody plants. The existing artificial plantations were created more than 70 years ago, so they do not effectively fulfill their ameliorative functions. The aim of the research is the selection of woody plants to form landscaping spaces of recreational type in sparsely forested regions. Bioecological studies of 18 tree species of the families Rosaceae, Oleaceae, Fabaceae, Fagaceae, Cornaceae, Caprifoliaceae, Corylaceae, Anacardiaceae, Rhamnáceae in dendrological collections of the Federal Research Centre of Agroecology RAS were carried out from July to October 2021 under field conditions. Conventional methods for evaluating crown structure on microclimatic parameters and ornamental value were applied. Original data were obtained by non-invasive method (Dualex Scientific device), which showed species-specificity of quantitative indicators of photopigments, their lability as an indicator of resistance to high temperatures was given. Dynamics of pigment indices in leaves showed that interspecific variation of the index is higher than intraspecific variation. The adapted assortment of trees and shrubs for arid regions has been identified. It is established that trees (Quercus robur) and shrubs with dense crowns (Ligustrum vulgare, Syringa vulgaris, Rosa rugose, etc.) reduce air temperature more effectively (by 2.2-4.3°C) than woody species with openwork crowns (species of genera Gleditsia and Robinia). It is shown that changing the composition of phytodiversity will increase the quality class of plantations. Quercus robur, Robinia pseudoacacia, Rhus typhina, Cotinus coggygria, species of Gleditsia and Amelanchier are recommended for creation of artificial plantations in the research region.

First report of 'Candidatus Phytoplasma rubi' associated with Rubus stunt disease of raspberry and blackberry in the Czech Republic.

Raspberries (Rubus idaeus L.), occurring in the temperate zone of the northern hemisphere and blackberries (R. fruticosus L.), cultivated and growing all over the world, are plant species of the family Rosaceae. These species are susceptible to phytoplasma infections, which cause Rubus stunt disease. It spreads uncontrolled by vegetative propagation of plants (Linck and Reineke 2019a) and by phloem-sucking insect vectors, especially Macropsis fuscula (Hemiptera: Cicadellidae) (de Fluiter and van der Meer, 1953; Linck and Reineke 2019b). During a survey in commercial field in June 2021, over 200 raspberry bushes cv Enrosadira exhibiting typical symptoms of Rubus stunt were observed in Central Bohemia. Symptoms included dieback, leaf yellowing/reddening, stunted growth, severe phyllody and fruit malformations. Most diseased plants were growing in the edge rows of the field (about 80%). No symptomatic plants were observed in the middle of the field. Similar symptoms were observed in private gardens in South Bohemia on raspberry cv Rutrago and blackberry (unknown cultivar) in June 2018 and August 2022, respectively. DNA was extracted using the DNeasy Plant Mini Kit (Qiagen GmbH, Hilden, Germany) from flower stems and parts affected by phyllody of seven symptomatic plants as well as flower stems, leaf midribs, and petioles of five asymptomatic field plants. The DNA extracts were analyzed by a nested polymerase chain reaction assay using universal phytoplasma P1A/P7A primers followed by R16F2m/R1m and the group-specific R16(V)F1/R1 primers (Bertaccini et al. 2019). All samples from the symptomatic plants yielded an amplicon of expected size, while no product was amplified in asymptomatic plants. The P1A/P7A amplicons from three selected plants (two raspberries and one blackberry, each from different location) were cloned and bi-directionally Sanger sequenced (GenBank Accession Nos.OQ520100-2). The sequences spanned nearly full-length of 16S rRNA gene, 16S-23S rRNA intergenic spacer, tRNA-Ile gene, and a partial 23S rRNA gene. BLASTn search revealed the highest sequence identity (99.8-99.9%, query coverage 100%) to 'Candidatus Phytoplasma rubi' strain RS (GenBank Accession No. CP114006). To further characterize the 'Ca. P. rubi' strains, all these three samples were subjected to multigene sequence analysis. Sequences from a major portion of the tuf, rplV-rpsC, rpsH-rplR, uvrB-degV, and rplO-SecY-map genes (Acc. Nos. OQ506112-26) were obtained as described previously (Fránová et al. 2016). Comparison to GenBank sequences confirmed their highest identity (99.6-100%, query coverage 100%) with 'Ca. P. rubi' RS strain, regardless of their geographic location and host (raspberry or blackberry). Recently, Bertaccini et al. (2022) suggested the 98,65 % 'Ca. Phytoplasma' strain identity threshold within 16Sr RNA sequences. In this survey, all three strains sequenced shared ≥99.73% sequence identity of the analysed 16S rRNA gene sequences and the high identity in the other genes with the reference 'Ca. P. rubi' RS strain. To our knowledge, this is the first report of Rubus stunt disease in the Czech Republic as well as the first molecular identification and characterization of 'Ca. P. rubi' from raspberry and blackberry in our country. As Rubus stunt disease is of great economic importance (Linck and Reineke 2019a), the pathogen detection and prompt removal of the diseased shrubs are essential to mitigating the spread and impact of the disease.

Understanding the salt overly sensitive pathway in Prunus: Identification and characterization of NHX, CIPK, and CBL genes.

Salinity is a major abiotic stress factor that can significantly impact crop growth, and productivity. In response to salt stress, the plant Salt Overly Sensitive (SOS) signaling pathway regulates the homeostasis of intracellular sodium ion concentration. The SOS1, SOS2, and SOS3 genes play critical roles in the SOS pathway, which belongs to the members of Na+/H+ exchanger (NHX), CBL-interacting protein kinase (CIPK), and calcineurin B-like (CBL) gene families, respectively. In this study, we performed genome-wide identifications and phylogenetic analyses of NHX, CIPK, and CBL genes in six Rosaceae species: Prunus persica, Prunus dulcis, Prunus mume, Prunus armeniaca, Pyrus ussuriensis × Pyrus communis, and Rosa chinensis. NHX, CIPK, and CBL genes of Arabidopsis thaliana were used as controls for phylogenetic analyses. Our analysis revealed the lineage-specific and adaptive evolutions of Rosaceae genes. Our observations indicated the existence of two primary classes of CIPK genes: those that are intron-rich and those that are intron-less. Intron-rich CIPKs in Rosaceae and Arabidopsis can be traced back to algae CIPKs and CIPKs found in early plants, suggesting that intron-less CIPKs evolved from their intron-rich counterparts. This study identified one gene for each member of the SOS signaling pathway in P. persica: PpSOS1, PpSOS2, and PpSOS3. Gene expression analyses indicated that all three genes of P. persica were expressed in roots and leaves. Yeast two-hybrid-based protein-protein interaction analyses revealed a direct interaction between PpSOS3 and PpSOS2; and between PpSOS2 and PpSOS1C-terminus region. Our findings indicate that the SOS signaling pathway is highly conserved in P. persica.

Warm temperature during floral bud transition turns off EjTFL1 gene expression and promotes flowering in Loquat (Eriobotrya japonica Lindl.)

The Rosaceae family includes several deciduous woody species whose flower development extends over two consecutive growing seasons with a winter dormant period in between. Loquat (Eriobotrya japonica Lindl.) belongs to this family, but it is an evergreen species whose flower bud initiation and flowering occur within the same growing year. Vegetative growth dominates from spring to late summer when terminal buds bloom as panicles. Thus, its floral buds do not undergo winter dormancy until flowering, but a summer heat period of dormancy is required for floral bud differentiation, and that is why we used loquat to study the mechanism by which this summer rest period contributes to floral differentiation of Rosaceae species. As for the deciduous species, the bud transition to the generative stage is initiated by the floral integrator genes. There is evidence that combinations of environmental signals and internal cues (plant hormones) control the expression of TFL1, but the mechanism by which this gene regulates its expression in loquat needs to be clarified for a better understanding of its floral initiation and seasonal growth cycles. Under high temperatures (>25ºC) after floral bud inductive period, EjTFL1 expression decreases during meristem transition to the reproductive stage, and the promoters of flowering (EjAP1 and EjLFY) increase, indicating that the floral bud differentiation is affected by high temperatures. Monitoring the apical meristem of loquat in June-August of two consecutive years under ambient and thermal controlled conditions showed that under lower temperatures (<25ºC) during the same period, shoot apex did not stop growing and a higher EjTFL1 expression was recorded, preventing the bud to flower. Likewise, temperature directly affects ABA content in the meristem paralleling EjTFL1 expression, suggesting signaling cascades could converge to refine the expression of EjTFL1 under specific conditions (Tª<25ºC) during the floral transition stage.

Whole-Genome Identification of Regulatory Function of CDPK Gene Families in Cold Stress Response for Prunus mume and Prunus mume var. Tortuosa.

Calcium-dependent protein kinases (CDPK) are known to mediate plant growth and development and respond to various environmental changes. Here, we performed whole-genome identification of CDPK families in cultivated and wild mei (Prunus mume). We identified 14 and 17 CDPK genes in P. mume and P. mume var. Tortuosa genomes, respectively. All 270 CPDK proteins were classified into four clade, displaying frequent homologies between these two genomes and those of other Rosaceae species. Exon/intron structure, motif and synteny blocks were conserved between P. mume and P. mume var. Tortuosa. The interaction network revealed all PmCDPK and PmvCDPK proteins is interacted with respiratory burst oxidase homologs (RBOHs) and mitogen-activated protein kinase (MAPK). RNA-seq data analysis of cold experiments show that cis-acting elements in the PmCDPK genes, especially PmCDPK14, are associated with cold hardiness. Our results provide and broad insights into CDPK gene families in mei and their role in modulating cold stress response in plants.

MIKC-Type MADS-Box Gene Family Discovery and Evolutionary Investigation in Rosaceae Plants

MADS-box is an important transcriptional regulatory element in plant growth. The MIKC-type MADS-box genes play important roles. However, the identification and evolutionary investigation of MIKC-type MADS-box family members in Rosaceae have been inadequate. Therefore, based on whole-genome data from Prunus dulcis, Prunus salicina, Prunus armeniaca, Prunus persica, Prunus mira, and Amygdalus nana, we depicted the evolution and divergence patterns of MIKC-type MADS-box family genes. In this study, we found 222 MIKC-type MADS-box genes from six Rosaceae species. These genes were classified into five clades, and only motif 1 was identified across all MIKC-type MADS-box proteins, except PdMADS42 and PmiMADS16. The structural properties of these genes significantly varied in sequence lengths between species, despite the high levels of similarity in exon lengths and numbers. MIKC-type MADS-box genes were found to have mostly been limited through purifying selection processes. Remarkably divergent regions were found inside the MIKC-type MADS-box genes’ domains, where clade III displayed more conserved activities and may have retained more original functions over the evolutionary process; clade I, on the other hand, may have undergone substantial functional limitations in a specific functional role. These findings provide the groundwork for future research into the molecular evolutionary processes of the plant MIKC-type MADS-box gene family.

Nutrient stoichiometric and resorption characteristics of the petals of four common urban greening Rosaceae tree species.

Nutrient resorption efficiency and stoichiometric ratios are important strategies for understanding plants. The present study examined whether or not the nutrient resorption process of plant petals is similar to that of leaves and other vegetative organs, as well as the nutrient restriction status of the whole flowering process of plants in urban ecosystems. Four Rosaceae tree species, Prunus yedoensis Matsum, Prunus serrulata var. lannesiana, Malus micromalus Makino, and Prunus cerasifera 'Atropurpurea', were selected as urban greening species to analyze the contents of C, N, P, and K elements in the petals and their stoichiometric ratios and nutrient resorption efficiencies. The results show interspecific differences in nutrient contents, stoichiometric ratios, and nutrient resorption efficiency of the fresh petals and petal litter of the four Rosaceae species. The nutrient resorption process was similar to that of the leaves before the petals fell. The nutrient contents of petals were higher than that of leaves at the global level, but the stoichiometric ratio and nutrient resorption efficiency of petals were lower. According to the "relative resorption hypothesis", N was limiting during the entire flowering period. The nutrient resorption efficiency of petals was positively correlated with nutrient variation. The correlation between the nutrient resorption efficiency of petals with nutrient content and stoichiometric ratio of petal litter was stronger. The experimental results provide scientific basis and theoretical support for the selection, scientific maintenance and fertilization management of Rosaceae tree species in urban greening.