Aquaporins play an essential role in regulating transmembrane water transport in plants. Postharvest water loss often leads to wilting of cut flowers, significantly reducing their ornamental value and posing a major challenge for commercial production. Based on previous transcriptomic analysis, fourteen AQP genes were identified and classified into four subfamilies. Among them, PIPs were predominantly expressed in floral organs, TIPs showed high expression in petals, while NIPs and SIPs were mainly expressed in green tissues. During the vase life period, the expression patterns of IpPIP2-2 and IpTIP1-3 were closely associated with early flower opening. Cut flower stems were either subjected to postharvest water loss to levels of 5 % (WL5) or 10 % (WL10), or pretreated with the aquaporins inhibitor HgCl2 or the activator beta-Mercaptoethanol (beta-ME). Morphological traits, water status, and the expression of AQP genes in petals were evaluated throughout the vase life period. The results demonstrated that postharvest water loss accelerated flower opening and petal shedding, reduced flower diameter, and shortened vase life. In addition, water loss promoted petal ethylene synthesis and increased MDA accumulation, significantly accelerating petal senescence. beta-ME significantly improved water uptake and accelerated flower opening, whereas HgCl2 showed no significant inhibitory effect during the vase period. During the early stages of flower opening, WL10 and beta-ME treatments markedly upregulated the expression of IpPIP2-2 and IpTIP1-3. Furthermore, water loss elevated the expression of key genes involved in ethylene synthesis and signal transduction pathways. These findings suggest that postharvest water loss triggers upregulation of aquaporin genes IpPIP2-2 and IpTIP1-3, which facilitates rapid water uptake and ethylene release in petals during the initial vase period. This study provides valuable insights into potential strategies for improving the quality and longevity of Itoh peony cut flowers.

Tree peony (Paeonia sect. Moutan) is one of the most important traditional ornamental woody flowers in China. However, its cultivation is often challenged by intense light and high temperatures during summer, leading to severe photo-oxidative damage and leaf senescence. In this study, we investigated the protective effects of polyolefin (PO) film on potted tree peony leaves under summer intense light and high temperature stress. Using tree peony 'Luoyanghong' as experimental material, we systematically compared the effects of two controls under natural light (CK1 and CK2, housed in separate greenhouses), single-layer PO film (PO1), and double-layer PO film (PO2) treatments. Microenvironment monitoring showed that single-layer and double-layer PO films reduced light intensity by 21% and 49%, respectively, while having limited effects on temperature. Morphological and physiological analyses indicated that PO film treatments effectively alleviated leaf yellowing and withering, maintained normal physiological morphology, and increased chlorophyll (Chl) and carotenoid (Car) content. The net photosynthetic rates of PO1 and PO2 plants were 18-36% higher than those of the control groups (CK1 and CK2). Evans blue and NBT staining revealed that PO film reduced cellular damage and reactive oxygen species (ROS) accumulation, while decreasing malondialdehyde (MDA) levels and increasing catalase (CAT) activity. Furthermore, qRT-PCR results showed that stress-responsive genes (Hsp70, Hsp90, and ATG5) and photosynthetic genes (RbcS and RbcL) were upregulated under PO film treatment. Principal component analysis (PCA) indicated that high light intensity, rather than temperature, was the primary factor causing leaf damage in potted tree peonies. The results show that PO film is an effective and low-cost agronomic measure, which can alleviate the intense light stress under high temperature conditions, relieve photo-oxidative damage, maintain photosynthetic performance, and increase the survival rate of potted tree peonies in summer.

Paeonia ostii 'Fengdan' is a multifunctional plant valued for its ornamental, medicinal, and edible properties. Its flowers emit a certain amount of volatile aromatic substances, showing potential applications in functional foods and natural fragrances. Selenium (Se) application can increase the Se content and nutrient quality of plant tissues. However, the impacts and mechanisms of Se application on the aroma substances of tree peony flowers remain largely elusive. In this study, 100 mg & sdot;L- 1 Na2SeO3 was sprayed approximately one week prior to flowering, and floral volatiles were collected at full bloom. The composition and content of volatile organic compounds (VOCs) and the expression of related genes were comprehensively analyzed by GC-MS, GC-IMS, PLS-DA, and RT-qPCR in tree peony flowers. GC-MS and GC-IMS identified 24 and 54 VOCs in tree peony flowers respectively, including terpenoids, alcohols, aldehydes, esters, benzenes, and alkanes. Se altered the composition and content of VOCs, especially increasing the release of key terpenoids such as beta-ocimene, 3,7-dimethyl-2,6octadien-1-ol, gamma-terpinene and linalool. PLS-DA analysis clearly distinguished the Se-treated samples from the control, with VIP scores identifying terpenoids as the major contributors. Moreover, the gene expression pattern revealed that Se upregulated the expression of five rate-limiting genes (PoDXR, PoMCT, PoCMK, PoHDS, and PoHDRS) in the MEP pathway and five downstream terpene synthase genes (PoTPS1, PoTPS2, PoTPS3, PoTPS4, and PoTPS8). These findings demonstrate that Se promotes floral terpene emission in tree peony by regulating the MEP pathway genes, offering new insights into enhancing floral quality in tree peony flowers.

The off-season cultivation of potted tree peonies is gradually expanding in China and Japan. However, maintaining the growth of these plants in natural environments during spring and summer poses significant challenges after they have bloomed in a greenhouse. Under excess light energy, the leaves often exhibit severe chlorosis, reducing plant vigor and death in extreme cases. This study investigated the intense spring light photodamage effect between natural light (Control) and 40 % shading (shading) to rejuvenate potted tree peonies post-flowering. We determined that leaf morphology, chloroplast ultrastructure, photosynthetic performance, protective enzyme activities, and the expression of genes involved in chlorophyll biosynthesis and degradation by colorimeter, TEM, Portable Photosynthesis System, Spectrophotometric method, and qPCR methods, respectively. The results indicated that tree peony leaves displayed symptoms of chlorosis and yellowing, with damaged chloroplast ultrastructure, decreased chlorophyll content, and increased redness value (a*), leading to significant photooxidative bleaching effects under spring natural light conditions. However, shading reduced the accumulation of O2 & sdot; and H2O2, increased POD and CAT activities, and decreased MDA content in the leaves. The expression levels of magnesium chelatase subunits CHLI and CHLH (CHLI and CHLH), geranylgeranyl reductase (CHLP), chlorophyll b reductase (NYC1), and mg-dechelatase (SGR) genes were significantly higher under shading conditions than that of the early stage under natural light from greenhouse transported to the field. Shading maintained the redox homeostasis and ensured the structure stability of chloroplast, improving the photosynthetic capacity of tree peony leaves. Overall, the experimental results indicate that moderate shading can effectively reduce photooxidative damage, proving that moderate shading is an effective technical strategy that can be used for transferring potted peonies from greenhouse to field management after flowering.

Potted cultivation serves as a vital strategy for industrialized production of standardized tree peonies, engineering seedlings capable of year-round and off-site transplantation. However, the limited root zone in potted conditions restricts root development, resulting in suboptimal seedling quality and hindering commercial-scale production. This study aimed to investigate the relationship between the accumulation characteristics of non-structural carbohydrates (NSCs) and growth performance in potted tree peonies, while also optimizing the transplantation technologies for potted cultivation. Using two-year-old grafted seedlings of ‘Luoyanghong’ as experimental material, the effects of root pruning, rooting agent, and Metarhizium anisopliae application on morphological development and NSCs accumulation in potted tree peony seedlings were investigated. The results showed that old roots serve as the primary storage organs for NSCs in the potted tree peony. Slight root pruning (25%) was beneficial for fibrous root growth, whereas excessive root pruning (50%) resulted in reduced biomass and NSCs accumulation. The application of a high concentration of rooting agents effectively promoted root growth and mitigated the adverse effects of root pruning. Furthermore, Metarhizium anisopliae significantly increased the stem number in potted tree peonies. The optimal protocol identified through range analysis involved 25% root pruning, followed by irrigation with a solution containing 750 mg·L−1 rooting agent and 20 million spores·mL−1 of Metarhizium anisopliae. The rational distribution of NSCs and coordinated growth across different organs enhanced NSCs accumulation in potted tree peonies. These results demonstrate that combining root pruning with the application of rooting agent and Metarhizium anisopliae can effectively increase NSCs accumulation, optimize plant morphology, and ultimately improve the quality of potted tree peony seedlings.

The use of the entomopathogenic fungus Metarhizium anisopliae is an important strategy for green control of plant pests. Metarhizium can also act as a plant endophyte to promote plant growth. In this paper, we verified the endophyticity of Metarhizium in the root system of ‘Fengdan’ tree peony (Paeonia ostii) by various means. And the growth-promoting effect of Metarhizium on the growth of tree peony seedlings was explored. The results showed that Metarhizium spores were able to attach to the surface of the tree peony root system in large numbers after 12 h of treatment; mycelium could be observed to colonize the young root cells after 60 d of treatment, and the designed Metarhizium ITS-specific sequences were able to observe clear specific bands in the tree peony root system. The application of 1 × 107 spores·mL−1 and 2 × 107 spores·mL−1 Metarhizium treatment groups elevated root indole-3-acetic acid (IAA) content by 13.9

Senescence-associated genes ( SAGs ) play a crucial role in regulating organ senescence in plant growth and development. However, their specific role in the florescence and senescence processes of cut peony flowers, particularly Itoh peonies, remains largely unclear. This study employed transcriptome analysis to investigate the expression patterns of IpSAG genes during the florescence and senescence of cut Itoh peony flowers in vases. Additionally, the function of IpSAG12 was examined using virus-induced gene silencing (VIGS) via vacuum infiltration to elucidate its role. The findings revealed that the opening and senescence of cut Itoh peonies in vases progress through three stages: early opening, middle transition, and later senescence. Notably, ethylene release followed a specific pattern, increasing sharply at the onset of flowering, then declining quickly during the early opening stage, displaying an ethylene-climacteric trait. Furthermore, the expression of the senescence- associated gene IpSAG12 was minimal during the opening and transition stages but significantly increased by 27.5 times during the senescence stage. Silencing IpSAG12 using VIGS extended the vase life of cut flowers by approximately 12 hours. This intervention resulted in a reduced electrolyte leakage rate, lower malondialdehyde (MDA) content, decreased ethylene release rate, reduced activity of 1-aminocyclopropane-1-carboxylic acid oxidase 1 (ACO1), and lower expression of IpACS1 and IpACO1 compared to the TRV control group. Conversely, the soluble protein content significantly increased in petals of the TRV- IpSAG12 group. Collectively, these findings suggest that IpSAG12 is a critical target gene in the ethylene signaling pathway that governs petal senescence in Itoh peonies.

Selenium (Se) is an essential micronutrient for human health, yet its deficiency remains prevalent worldwide. Biofortification through foliar Se application is an effective strategy to enhance Se levels in crops. Paeonia ostii ‘Fengdan’ is a multifunctional woody plant with potential for Se enrichment, though its Se uptake and transformation mechanisms remain unclear. This study systematically investigated the effects of foliar-applied Na2SeO3 (0–200 mg L−1) on Se uptake, accumulation, speciation, and nutritional quality in tree peony. Results showed that Se uptake increased with higher Na2SeO3 concentrations, displaying a clear dose-dependent pattern across all organs. Se accumulation significantly enhanced, with a pronounced shift in distribution towards above-ground organs under experimental conditions. Notably, tree peony exhibited strong biotransformation capacity, converting over 73% of Se in leaves and over 81% in seeds into organic forms, primarily SeCys2 and SeMet, with minor MeSeCys. Comprehensive evaluation indicated that 100 mg L−1 Na2SeO3 yielded optimal results, significantly enhancing leaf and seed biomass, increasing seed nutrient contents (soluble proteins, sugars, phenolics), and improving the unsaturated fatty acid profile of seed oil. These findings highlight tree peony’s potential as an efficient bioreactor for organic Se and provide a theoretical foundation for developing Se-enriched products from tree peony.

(1) Tree peony (Paeonia suffruticosa Andrews) is a woody ornamental plant originating from China, and beloved by people worldwide. Non-structural carbohydrates (NSCs) play a crucial role in regulating the flowering quality of tree peonies in both field and potted conditions. However, the effects of NSCs accumulation and allocation in various organs during the vegetative growth stage on the flowering quality of tree peony under forcing culture remains unclear. (2) Two-year-old grafted seedlings of tree peony cv. ‘Luoyanghong’ were subjected to orthogonal treatments to investigate the role of NSCs accumulation in plants’ developmental process. We measured leaf photosynthetic capacity, NSCs accumulation in the organs of seedlings, observed key ornamental characteristics of flowering quality under forcing culture conditions, and evaluated the qualities of seedlings and flowers using the seedling index (SI) and flowering index (FI), respectively. (3) There was a significant positive correlation between leaf photosynthetic capacity and NSCs accumulation in both the whole plant and roots of potted tree peony. Roots were identified as the primary organs for NSCs accumulation in potted tree peonies. Sufficient NSCs accumulation in the plant, particularly in the roots during the defoliation period, was essential not only for enhancing the seedling quality of potted tree peonies but also for improving the flowering quality under forcing culture conditions. Both the seedling index (SI) and flowering index (FI) exhibited a significant dose-response with increasing root NSCs accumulation at defoliation. The T3 group, which involved slight root pruning (by 25%), combined with a high-concentration rooting agent (750 mg·L−1) and Metarhizium anisopliae (20 million U·mL−1), resulted in the highest photosynthetic capacity, SI, FI and NSCs accumulation status (NSCAR), making it the optimal treatment combination. (4) This finding indicates that increasing NSCs accumulation in the roots of potted tree peonies is a crucial biological foundation for producing high-quality potted flowers under forcing culture conditions, which provide new insights into the importance of NSCs in tree peony flowering and may improve the production technology for high-quality potted tree peony flowers under forcing culture conditions.

Auxin gradient on either side of the abscission zone play a crucial role in regulating organ abscission during plant senescence. Yet, the impact of auxin on the opening and senescence of cut peony flowers, specifically Itoh peony 'Bartzella', remains elusive. We employed the frozen section method to investigate the cell morphology within the petal abscission zone. Additionally, we quantified auxin levels via enzyme immunoassay and assessed the expression of genes related to indole-3-acetic acid (IAA) levels. Through our analyses, we pinpointed the critical gene, IpAUX1. Further investigation of IpAUX1 involved virus-induced gene silencing (VIGS) and transient overexpression techniques, allowing us to assess its role both in vitro flowers, through vacuum application, and in vivo flowers, via injection. Significant alterations were observed in the structure and cell morphology of the abscission zone correlating with the process of petal abscission, alongside noticeable auxin gradient. Silencing IpAUX1 led to a noticeable delay in petal abscission for both in vitro flowers and vivo flowers, while its transient overexpression hastened this process. This silencing effect was accompanied by a reduction in IAA levels around the abscission zone and a subsequent delay in the erasure of the auxin gradient. It also resulted in the downregulation of several genes: the auxin response factor IpARF1, ethylene synthesis-related genes IpACS1 and IpACO1, and cell wall hydrolysis-related genes IpPME1 and IpPG1. Conversely, the expression of genes involved in auxin synthesis gene IpYUCCA10, auxin efflux carrier IpPIN1, and the ethylene receptor IpETR1 saw significant upregulation. This study concludes that the auxin influx carrier IpAUX1 enhances the abscission zone cells' responsiveness to ethylene by modulating the auxin gradient. This action promotes cell hydrolysis within the abscission zone, thereby encouraging petal abscission. Our findings underscore the pivotal role of IpAUX1 as a positive regulator during the process of petal abscission.

(1) Background: Tree peonies display extensive cultivar diversity due to widespread hybridization, resulting in a complex genetic architecture. This complexity complicates the selection of universal reference genes across different cultivars for qRT-PCR analyses. Paeonia suffruticosa ‘Doulv’, notable for its unique green blooms in China, exhibits chlorosis post-flowering and features petaloid stamens and pistils. (2) Methods: Based on published literature and RNA-seq data from ‘Doulv’, nine candidate reference genes—ACT (Actin), TUB (β-Tubulin), UBC (Ubiquitin Conjugating Enzyme), UBQ (Ubiquitin), UPL (Ubiquitin Protein Ligase), PP2A (Protein Phosphatase 2A), PP2C (Protein Phosphatase 2C), MBF1A (Multiprotein Bridging Factor 1A), and GAPDH (Glyceraldehyde-3-Phosphate Dehydrogenase)—were selected. Their expression stability was assessed across various tissues and developmental stages of ‘Doulv’ flowers using qRT-PCR, with evaluations conducted via GeNorm_v3.5, NormFinder_v20, and BestKeeper_v1.0. Gene cloning and expression analyses of PsCUC3, including its subcellular localization, were performed. (3) Results: GAPDH and ACT were identified as the most stable reference genes in petaloid stamens across various developmental stages of ‘Doulv’, whereas UBC and MBF1A were optimal across different tissues. Notably, specific conserved amino acids in PsCUC3 from ‘Doulv’ diverged from those in NAM/CUC3 proteins of other species, impacting its protein structure. PsCUC3 expression analysis revealed no correlation with chlorophyll content in petaloid stamens but an association with petaloid organ development. Furthermore, PsCUC3 was predominantly localized in the nucleus. (4) Conclusions: This study comprehensively evaluated suitable reference genes using GeNorm_v3.5, NormFinder_v20, and BestKeeper_v1.0 software, establishing a robust qRT-PCR detection system for ‘Doulv’ peony. These results provide a solid experimental foundation for further research on ‘Doulv’ peony. Building on this experimental foundation, the functional analysis of the PsCUC3 gene was conducted. The findings suggest a potential association between the PsCUC3 gene and floral morphology alterations in ‘Doulv’, identifying PsCUC3 as crucial for understanding the molecular mechanisms influencing floral structure in tree peonies.

Corynebacterium glutamicum is an important industrial production strain that is widely used in amino acid fermentation, biopharmaceuticals, and other fields. It is particularly important to develop efficient genome editing methods for the targeted modification of C. glutamicum production strains. Currently, the gene editing system of C. glutamicum is inefficient and time-consuming. In this paper, we reported on a Francisella novicida (Fn) CRISPR-Cpf1-based system for genome editing. The system used linear DNA detached from the plasmid, and, with the assistance of the recombinase RecET, gene deletion was achieved by simultaneous electrotransformation of linear DNA with a plasmid carrying the FnCpf1 and crRNA expression cassette for double-strand breaks of the genome. Compared with previous all-in-one plasmids, this system reduced the time for one round of constructing recombinant plasmids and shortened the editing cycle by about 24 h. Finally, we successfully constructed an engineered strain (X−2) with high L-valine production by using the linear DNA-mediated gene deletion system. This method is of great importance for accelerating the process of metabolic engineering modification of C. glutamicum and its further application in high value-added products.

In order to screen the reference genes of Itoh peony ‘Bartzella’, this study took the petals of ‘Bartzella’ cut flowers at different developmental stages as well as the root, stem, petiole, leaf, receptacle, sepal, petal, stamen and ovary as experimental materials. Combined with the existing ‘Bartzella’ transcriptomic data of our lab and conventional reference genes, ten candidate reference genes（GAPDH, ACT, UBQ,β-TUB, PP2A, CYP, EF-1α, F3H, TIP41, UBC） were screened out. Real-time quantitative PCR and geNorm,NormFinder, BestKeeper and RefFinder software were used for evaluation. The results showed that the double genes of UBQ and TIP41 were the best reference gene combination for the petals at different developmental stages of ‘Bartzella’ cut flowers. β-TUB, UBQ and ACT could be used as the best combination of reference genes for different organs of ‘Bartzella’ plant. Meanwhile, UBQ and TIP41 were used as double reference genes to analyze the expression patterns of five senescence related genes（ACS1, ACO1, ETR1,SAG12 and SAG21） of ‘Bartzella’ cut flower petals. The results showed that those five genes played an important role in the senescence process of Itoh peony ‘Bartzella’ cut flowers based on two double reference genes analysis. The combinations of selected internal reference genes laid an experimental foundation for further study on the differential expression of functional genes in the Itoh peony.

Tree peony is the most popular and important ornamental plant in China and has many different flower types. Although many studies about tree peony cultivation have been published, the regulatory mechanism of floral organ identity has not been explored. Paeonia ostii 'Fengdan' is a typical single-flower variety, and many important tree peony cultivars in China originated from homoploid hybridization between 'Fengdan' and other Paeonia species. Peony tea made from 'Fengdan' has already been introduced to the market, and the quality and price of peony tea are closely related to the flower type of 'Fengdan'. This research cloned six floral organ identity genes in 'Fengdan', namely, PsAP1fd, PsAP2fd, PsAP3fd, PsPIfd, PsAGfd, and PsSEP 1fd. The bioinformatics analysis was performed, and results showed that all these genes encoded MADS-box proteins, except PsAP2fd, and PsAP2fd encoded an AP2 protein. Five MADS-box proteins encoded by these genes contained two conserved motifs: MADS-MEF2 and K-box domain PsSEP1fd was hydrophilic and stable, whereas the other five proteins were hydrophilic and unstable. The results of qRT-PCR displayed that PsAP1fd was mostly observed in the petals and sepals, and PsAP2fd was mostly found in the petals. PsAP3fd had strong expressions in the stamens and petals. The highest expression level of PsPIfd was observed in the petals, followed by that in the stamens. The highest expression level of PsAGfd was observed in the pistils, followed by that in the stamens. PsSEP1fd was mainly expressed in the pistils. These results showed that the ABCE model was effective in the flower type formation of 'Fengdan'. Our work would help reveal the molecular mechanism underlying flower type formation in 'Fengdan' and promote quality control for peony tea products.

伊藤牡丹'巴茨拉'是适合反季节盆花生产的优良品种.为探讨春节异地牡丹促成栽培中水溶肥调控盆栽'巴茨拉'开花效果,在茎伸长初期用0、0.8、1.2和1.6 g·L-1 均衡型水溶肥(N-P-K=20-20-20+TE)进行灌根处理,观察测定水溶肥对植株生长发育、开花质量及相关生理生化指标的影响.结果表明:(1)水溶肥灌根能显著促进盆栽'巴茨拉'各部器官的生长和养分积累.(2)随水溶肥浓度的增加,叶片叶绿素、可溶性蛋白质和可溶性糖含量以及花枝长度、粗度和花蕾直径随之增大,各器官中氮素和钾素营养水平亦呈现增加趋势;中高浓度(1.2 g·L-1和1.6 g·L-1)水溶肥条件下,花蕾直径分别比对照显著增大了 4.4％和7.7％(P＜0.05),使花促成栽培时间缩短了 4.45 d和2.65 d,最佳观赏期延长了 5.08 d和1.70 d.(3)中浓度水溶肥处理盛开期花朵最大,花朵直径和单株成花率分别比对照提高了 16.0％和13.5％(P＜0.05),并显著提高了花瓣中类黄酮、类胡萝卜素含量及色彩黄度(P＜0.05).研究发现,适宜浓度的水溶肥能够显著提高'巴茨拉'促成栽培过程中枝叶花的协调性,使用水溶肥应成为'巴茨拉'盆花生产的基础管理措施;反季节栽培伊藤牡丹'巴茨拉'建议使用1.2 g·L-1均衡型水溶肥进行灌根.

Tree peony is the most popular and important ornamental plant in China and has many different flower types. Although many studies about tree peony cultivation have been published, the regulatory mechanism of floral organ identity has not been explored. Paeonia ostii „Fengdan‟ is a typical single-flower variety, and many important tree peony cultivars in China originated from homoploid hybridization between „Fengdan‟ and other Paeonia species. Peony tea made from „Fengdan‟ has already been introduced to the market, and the quality and price of peony tea are closely related to the flower type of „Fengdan‟. This research cloned six floral organ identity genes in „Fengdan‟, namely, PsAP1fd , PsAP2fd , PsAP3fd , PsPIfd , PsAGfd , and PsSEP1fd . The bioinformatics analysis was performed, and results showed that all these genes encoded MADS-box proteins, except PsAP2fd , and PsAP2fd encoded an AP2 protein. Five MADS-box proteins encoded by these genes contained two conserved motifs: MADS-MEF2 and K-box domain. PsSEP1fd was hydrophilic and stable, whereas the other five proteins were hydrophilic and unstable. The results of qRT-PCR displayed that PsAP1fd was mostly observed in the petals and sepals, and PsAP2fd was mostly found in the petals. PsAP3fd had strong expressions in the stamens and petals. The highest expression level of PsPIfd was observed in the petals, followed by that in the stamens. The highest expression level of PsAGfd was observed in the pistils, followed by that in the stamens. PsSEP1fd was mainly expressed in the pistils. These results showed that the ABCE model was effective in the flower type formation of „Fengdan‟. Our work would help reveal the molecular mechanism underlying flower type formation in „Fengdan‟ and promote quality control for peony tea products.

[目的]探讨牡丹切花衰老过程中花瓣萎蔫脱落的生理机制,为更好地开发牡丹切花贮藏保鲜技术提供理论依据.[方法]以'洛阳红'牡丹为试材,分别用去离子水(CK)、20μL·L-1乙烯拮抗剂可利鲜(AVB)、20 μL·L-1乙烯释放剂乙烯利(CEPA)处理1h时及20 μL·L-1可利鲜预处理1h后再用20 μL·L-1乙烯利处理1 h (AVB+CEPA),然后插入去离子水进行单枝瓶插,观测不同预处理的生理效应.利用显微镜观察花瓣离层细胞形态,通过拉力试验测定瓶插过程中花瓣抗脱落力,运用生理生化手段测定乙烯与生长素代谢、离层水解相关酶活性和PsETR1、PsCTR1、PsEIN3、PsERF、PsYUCCA10、PsPIN1、PsPME1、PsPG1及PsBG1的相对表达量.[结果]牡丹'洛阳红'切花花瓣基部有明显的离层结构;AVB预处理明显推迟了切花乙烯跃变出现的时间,乙烯释放峰值降低34.9％(P＜0.05),提高了花瓣的抗脱落力,降低了花瓣基部多聚半乳糖醛酸酶(PG)、β-葡萄糖苷酶(BG)活性和PsPG1、PsBG1表达量,延缓了牡丹切花的衰老进程,显著延长了切花的瓶插寿命;外源CEPA明显加快了花瓣内源乙烯的释放速率,提高了生长素氧化酶(IAAO)、PG和BG活性,加快了切花花瓣的离层细胞的衰老,减小了花瓣的抗脱落力,从而促进了花瓣的萎蔫脱落;AVB+CEPA复合预处理瓶插寿命和最佳观赏期与对照组相差不大,CEPA能够部分抵消AVB的生理效应.[结论]对乙烯敏感型切花牡丹'洛阳红',内源生长素参与了乙烯促进花瓣离层细胞脱落的过程,控制乙烯是改善其切花瓶插品质的基础途径.

[目的]探究‘凤丹’牡丹种苗的最适移栽时期,为其丰产栽培技术提供参考.[方法]以3年生‘凤丹’牡丹实生种苗为试验材料,设置8个移栽时期,通过大田对比试验,分析移栽后根系活力、叶片光合性能及生物量的变化;采用主成分分析和综合评价的方法对不同移栽时期的成苗效果进行评价.[结果]移栽期可能通过移栽时气温、土壤温度和移栽后土壤积温等环境因素影响‘凤丹’牡丹新根和植株的发育,适时移栽显著促进牡丹苗体的生长发育.在不同的移栽时期,‘凤丹’牡丹植株生长期间的新根总数、木质化新根数、根系活力、叶面积、叶片SPAD值、净光合速率、枝条粗度、根生物量、枝条生物量、总生物量和壮苗指数均有一定差异,而枝条长度和根冠比没有显著差异.9月29日与11月28日移栽相比,单株木质化新根质量和叶面积分别增加了90.26％和51.22％,根系活力和净光合作用速率分别提高了93.53％和60.98％,单株生物量增加了46.00％.经通径分析、主成分分析和综合评价表明:9月29日移栽的‘凤丹’牡丹成苗效果最好.[结论]本研究依据植株生物量、壮苗指数与移栽期气象环境要素的依赖关系,明确9月中旬至10月下旬,日均气温15～20℃气候条件,是‘凤丹’牡丹的最适移栽期.

Cleome gynandra and Cleome hassleriana , which are C 4 and C 3 plants, respectively, are two species of Cleome. The close genetic relationship between C. gynandra and C. hassleriana provides advantages for discovering the differences in leaf development and physiological processes between C 3 and C 4 plants. MicroRNAs (miRNAs) are a class of important regulators of various biological processes. In this study, we investigate the differences in the characteristics of miRNAs between C. gynandra and C. hassleriana using high-throughput sequencing technology. In total, 94 and 102 known miRNAs were identified in C. gynandra and C. hassleriana , respectively, of which 3 were specific for C. gynandra and 10 were specific for C. hassleriana . Ninety-one common miRNAs were identified in both species. In addition, 4 novel miRNAs were detected, including three in C. gynandra and three in C. hassleriana . Of these miRNAs, 67 were significantly differentially expressed between these two species and were involved in extensive biological processes, such as glycol-metabolism and photosynthesis. Our study not only provided resources for C. gynandra and C. hassleriana research but also provided useful clues for the understanding of the roles of miRNAs in the alterations of biological processes in leaf tissues during the evolution of the C 4 pathway.

In this paper,the effects of natural deterioration of tree peony seed under two storage periods on the quality of seed oil by supercritical CO2,extraction of tree peony seeds were analyzed.The results showed that compared to newly harvested seeds,oil from naturally aged seeds stored 12 months under room temperature had a darker color,significantly increased contents of acid value,peroxide value,and AFB1,markedly decreased content of vitamin E,marginally increased the BaP content under the edible vegetable oil safety standards of China,but not clear change in fatty acid composition and contents.These results suggested that the storage period of oil tree peony seeds should be shortened in order to avoid poor oil quality of tree peony seed and increase risk to health.