Comprehensive analyses of the proteome and ubiquitome revealed mechanism of high temperature accelerating petal abscission in tree peony

Tree peony(Paeonia suffruticosa Andrews)is a well-known ornamental plant with high economic value,but the short fluorescence is a key obstacle to its ornamental value and industry development.High temperature accelerates flower senescence and abscission,but the associated mechanisms are poorly understood.In this study,the tandem mass tag(TMT)proteome and label-free quantitative ubiquitome from tree peony cut flowers treated with 20℃for 0 h(RT0),20℃or 28℃for 60 h(RT60 or HT60)were examined based on morphological observation,respectively.Totally,6970 proteins and 1545 lysine ubiquitinated(Kub)sites in 844 proteins were identified.Hydrophilic residues(such as glutamate and aspartate)neighboring the Kub sites were in preference,and 36.01%of the Kub sites were located on the protein surface.The differentially expressed proteins(DEPs)and Kub-DEPs in HT60 vs RT60 were mainly enriched in ribosomal protein,protein biosynthesis,secondary metabolites biosynthesis,flavonoid metabolism,carbohydrate catabolism,and auxin biosynthesis and signaling revealed by GO and KEGG analysis,accompanying the increase of endogenous abscisic acid(ABA)accumulation and decrease of endogenous indoleacetic acid(IAA)level.Additionally,the expression patterns of six enzymes(SAMS,ACO,YUC,CHS,ANS and PFK)putatively with Kub modifications were analyzed by proteome and real-time quantitative RT-PCR.The cell-free degradation assays showed PsSAMS and PsACO proteins could be degraded via the 26 S proteasome system in tree peony flowers.Finally,a working model was proposed for the acceleration of flower senescence and abscission by high temperature.In summary,all results contributed to understanding the mechanism of flower senescence induced by high temperature and prolonging fluorescence in tree peony.

Effect of exogenous GA3 on flowering quality, endogenous hormones, and hormone-and flowering-associated gene expression in forcing-cultured tree peony（Paeonia suffruticosa）

Gibberellins(GAs)promote flowering in the forcing-cultured tree peony(Paeonia suffruticosa),however,the mechanism of regulating flowering is not fully understood.In this study,exogenous GA3 was applied to five-year-old Luoyang Hong plants to explore responses in terms of endogenous hormones,flowering quality,and the hormone-and flowering-associated gene expression.Exogenous GA3 application significantly promoted flower bud development and new branch growth,as well as improved flowering quality.Exogenous GA3 application also stimulated the synthesis of endogenous GA3 and indole-3-acetic acid(IAA)but reduced abscisic acid(ABA)levels.To further elucidate the regulatory mechanism,eight genes for GA biosynthesis and signaling,including PsCPS,PsKS,PsGA3ox,PsGA2ox,PsGID1b,PsGID1c,PsDELLA,and PsGID2 were cloned for the first time,and sequence analysis was also performed.The results suggested that all the cloned genes have conserved structure as each homologous gene reported in the other species.Phylogenetic trees constructed by the each cloned gene showed that the phylogenetic evolutionary relationship of P.suffruticosa was closely related to Vitis vinifera.The expression patterns of the above genes,and genes for ABA and IAA biosynthetic and signaling,and the flowering time were also investigated.Most of the above genes showed higher expression in the control buds than those in the GA3 treated buds at six developmental stages,whereas the expression levels of PsSOC1 and PsSPL9 were up-regulated by GA3 treatment.The results also showed that the GA-biosynthetic and signaling pathways are conserved in tree peony,and the PsCPS,PsGA3ox,PsGA2ox,PsGID1,PsDELLA,and PsGID2 genes are necessary for feedback regulation of GAs.Furthermore,hormone changes promoted PsSOC1 and PsSPL9 expression,and repressed PsSVP expression,which contributed to the improvement flowering quality in tree peony of forcing culture.

RAPD-PCR Analysis on Genetic Relationships Between Cultivars of Tree Peony

Random amplified polymorphic DNA (RAPD) was used to analyze genetic polymophism of 35 Tree Peony cultivars with 7 different color groups. Thirty four primers amplified 418 DNA fragments and 337 polymorphic bands (80.6%), including specific DNA markers for 18 cultivars that could be used to differentiate cultivars. The UPCMA method was used to analyze the genetic relationship among cultivars. The results showed that 35 Peony cultivars could be divided into 2 cluster groups when using similarity criteria of 1.5, and into 4 cluster groups when using similarity criteria of 1.0. The result confirmed that the flower color has no relation to the genetic clusters and the Tree Peony cultivars originated from the same area has close genetic relationship. Therefore, genetic background has no large effect on the genetic relationship. The sequence based on polymorphic rate from high to low was Blue groups > Yellow groups > Bark red groups > Blake groups > White groups>Green groups>Red groups.

Identification of differentially expressed genes associated with bud dormancy release in tree peony(Paeonia suffruticosa) by suppression subtractive hybridization

A subtractive cDNA library was developed to study genes associated with bud dormancy release in tree peonies. In order to identify genes that are highly expressed in buds released from dormancy, 588 clones were examined by differential screening. Of these, 185 clones were selected to be sequenced. A total of 37 unique sequences were obtained of which only 31 sequences have matches in the NCBI database or the Arabidopsis thaliana protein database. Semi-quantitative RT-PCR was used to confirm further the expression profiles for 12 transcripts identified within the subtractive cDNA library. Gene ontology analyses indicated that many of the different genes identified have unknown or hypothetical functions while it is speculated that other genes play different mo- lecular roles. In our study, genes involved in bud dormancy release were growth-related or stress-responsive, while low-temperature-induced ribosomal proteins may also play a role in bud dormancy release. Our results provide interesting information for further understanding of the molecular mechanism of bud dormancy release in tree peonies.

Genetic diversity and relatedness analysis of nine wild species of tree peony based on simple sequence repeats markers

Tree peony has nine wild species,but the evolutionary relationship of them is still unclear.Here,a total of 274 specimens from 22 natural populations of nine wild species were collected,and their genetic diversity and similarity was analyzed based on Simple Sequence Repeats(SSR)molecular markers.A total of 106 alleles were generated based on 20 primers and with an average of 5.3 alleles per primer.Shannon’s information index(I)ranged from 0.6333 to 1.7842,and the average of Nei’s genetic diversity coefficient(H)was 0.5771.Polymorphism Information Content(PIC)value varied from 0.29 to 0.77,ten of these primers had high polymorphism(PIC≥0.50).All the above genetic parameters of primers reflect more rich genetic diversity information compared with other researches using SSR molecular markers to study the genetic diversity of tree peony wild species.At the population level,the lowest and highest degree of genetic diversity occurred in Paeonia ludlowii-P1 and P.delavayi-P3 population,respectively.Whereas at species level,the genetic diversity of 9 wild peony species was as follows:P.lutea>P.delavayi>P.rockii>P.qiui>P.ostii>P.decomposita>P.potaninii>P.spontanea>P.ludlowii.Furthermore,cluster analysis at species level divided the nine wild tree peony species into two branches.In branch I,the closest phylogenetic relationship was found between P.ostii and P.rockii,followed by P.spontanea,P.qiui,and P.decomposita.In branch II,the closest relationship occurred between P.lutea and P.delavayi,followed by P.potaninii and P.ludlowii.Clustering results supported the division of tree peonies into two subsects(Delavayanae and Vaginatae),it also supported P.potaninii and P.ludlowii as independent species.The results provided novel insight into the genetic diversity and phylogenetic relationship of nine wild tree peony species.It will help formulate comprehensive protection measures of wild germplasm resources and select proper parents for distant hybridization in the future.

Development and application of microsatellite markers within transcription factors in flare tree peony(Paeonia rockii)based on next-generation and single-molecule long-read RNA-seq

Tree peonies native to China are a precious crop with ornamental,medicinal and edible oil properties,of which flare tree peony(Paeonia rockii)is one of the most significant germplasms in Paeonia.The development and application of expressed sequence tag-simple sequence repeat(EST-SSR)markers are very valuable for genetic and breeding applications,but EST-SSR resources for the genus Paeonia are still limited.In this study,we first reported the development of SSRs within transcription factors(TFs)in P.rockii based on next-generation sequencing(NGS)and single-molecule long-read sequencing(SMLRS).A total of 166 EST-SSRs containing six nucleotide repeat types were identified from 959 candidate TFs associated with yield,with an average of one SSR per 5.83 unigenes.In total,102(61.45%)pairs of primers produced amplification products in the two RNA-seq cultivars.Among them,58(56.86%)pairs of primers from 18 gene families(AP2,b HLH,HSF,etc.)were identified to be polymorphic both in the parents of a linkage mapping population and in eight randomly selected accessions of P.rockii.Further,the 58 EST-SSRs indicated a high level of informativeness with PIC values ranging from 0.32 to 0.91(mean 0.70)after assessment in 37 tree peony accessions.Transferability studies indicated that the amplification ratio of the 58 pairs of primers ranged from 89.66 to 100%across seven species of Paeonia.In addition,a genetic relationship study was performed in 62 accessions.Cluster analysis using the neighbour-joining(NJ)tree demonstrated that major clusters corresponded to the known pedigree trees.Taken together,these newly developed EST-SSRs have a potential use in the conservation of tree peony germplasm and marker-assisted selection(MAS)breeding.

Transcriptome Profiling of Flower Development Reveals Key Genes Mediating Yellow Formation in Tree Peony

Tree peony cultivars with yellow flowers are rare and valuable,but the molecular mechanism of pigment accumulation is not clear.In this study,the petal transcriptome of three developmental stages were sequenced to determine the differentially expressed genes(DEGs)regulating yellow flowers color.The results showed that 10,842 and 12,022 DEGs were screened in stage 1 vs.stage 2 and in stage 2 vs.stage 3,respectively.Through analysis of flavonoid structural genes(FSGs),we found that the transcription level of DFR was very low in the three developmental stages.In a small group of cultivars,the DFR transcription level of red flowers was 862 times higher than that of yellow flowers.These data suggested that the flavonoid pathway is interrupted in the later stage due to the low transcriptional level of DFR,which limits the biosynthesis of anthocyanins in yellow flowers.The transcription levels of F3’H and FLS were upregulated from stage 1 to stage 2,while those of CHI and FLS were downregulated from stage 2 to stage 3.In addition,67 MYBs and 44 bHLHs showed similar transcription profiles with different members of FSGs.The results deepen our understanding of the molecular mechanism of yellow pigment accumulation in tree peony.

Osmotic Regulation,Antioxidant Enzyme Activities and Photosynthetic Characteristics of Tree Peony(Paeonia suffruticosa Andr.)in Response to High-Temperature Stress

Tree peony(Paeonia suffruticosa Andr.)is a traditional Chinese flower,which prefers cool weather.However,high temperature in summer in the middle and lower reaches of the Yangtze River restricts its growth and development.In this study,osmotic regulation,antioxidant enzyme activities,and photosynthetic characteristics of tree peony in response to high-temperature stress were investigated.The results showed that high-temperature stress had destroyed the cell membrane,manifested as the increased relative electrical conductivity and malondialdehyde content.Moreover,high-temperature stress led to excessive accumulation of reactive oxygen species,thereby,activating antioxidant enzyme activities.Also,photosynthetic parameters and chlorophyll fluorescence parameters directly reflected the damage to the photosystem II reflection center under high-temperature stress.In addition,high-temperature stress led to stomatal closure and chloroplast damage.This study revealed the physiological responses of tree peony to high-temperature stress,laying a foundation for the promotion of tree peony in high-temperature areas and the improvement of high-temperature resistance.

清代北京皇家园林中的牡丹史考

通过对清朝京西畅春园、圆明园与颐和园3处皇家园林中牡丹栽培应用史考证,讨论了牡丹与国势兴衰的关联及其它们的政治文化价值和对中国牡丹文化发展产生的积极影响。皇家园林中的牡丹,反映了清代皇家及其统治阶层在政治上追求强国富民的政治理想与抱负,在生活上热爱“国色天香”牡丹自然美的审美情趣与文化需要,尤其是圆明园镂月开云牡丹台,康熙、雍正、乾隆“三皇”观牡丹的历史事件,不仅使牡丹成为康乾盛世的象征,同时也为牡丹文化增添了政治成分,成为标志满汉一统、民族融合的文化纽带,使中国传统牡丹文化内容更为丰盈而耀眼。

九种牡丹根际土壤中解有机磷细菌的筛选及解磷能力评价

牡丹作为我国重要的原生植物资源,具有较大的理论研究和开发应用价值。探索资源高效、环境友好的施肥管理方式更有利于促进牡丹产业的绿色可持续发展。本研究以9种牡丹的根际土壤为材料,利用平板稀释法对根际土壤中具有解有机磷能力的细菌进行分离筛选,并采用16S rRNA基因测序技术鉴定菌株种类,结合溶磷圈法和钼锑抗比色法评价菌株的解磷能力。结果表明:从9种牡丹的根际土壤中筛选出14株解有机磷细菌,包括假单胞菌属3株,节杆菌属3株,贪铜菌属3株,芽孢杆菌属2株,红球菌属1株,链霉菌属1株,固氮菌属1株。不同解有机磷菌株的溶磷指数在1.5—2.9,溶磷效率为54.6%—194.6%,对应培养液中的速效磷含量在0.060—5.853 mg∕L,对植酸钙的活化率为30.48%—91.22%,其中,从杨山牡丹根际土壤中分离的菌株PO15(隶属于芽孢杆菌属)的溶磷指数、溶磷效率和速效磷含量均最高,其降解有机磷的能力最强。该研究对牡丹高效解磷菌株的筛选及专用微生物菌肥的研发具有重要的参考价值,也为实现牡丹产业绿色发展提供了新的思路和理论支撑。

‘凤丹’牡丹栽培及产业发展综述

该研究总结了影响‘凤丹’生长发育、产量的各项因素并结合阐述现阶段‘凤丹’综合开发利用的现状,揭示了‘凤丹’产业精细化发展所面临的主要挑战,以期对‘凤丹’以及整个牡丹产业的可持续发展提供参考依据。

覆膜方式对盆栽牡丹基质水热效应与植株生长的影响

探索不同覆膜方式对盆栽牡丹基质水热效应与植株生长的影响,以期寻找轻简高效的盆栽牡丹管理方式,对盆栽花卉工程苗的推广应用具有重要意义。覆膜是应对农业生产中降水少、热量不足的重要农艺措施,有助于改善根际微生态环境,提高农作物产量和品质。本试验以盆栽不覆膜为对照(T0),设置5种覆膜方式:盆口上覆白膜(T1)、盆口上覆黑膜(T2)、盆口上覆白膜加盆底下覆黑膜(T3)、塑料盆上下均覆黑膜(T4)和塑料盆上下均覆白膜(T5),研究不同覆膜方式下盆栽牡丹基质的水热环境变化及其对植株发育和光合性能的影响。结果表明,与T0相比,冬春季T1和T5处理基质日最高温度均提高5.0℃以上,春季T1和T516天每盆分别累积节水1.065 kg和1.195 kg,说明覆膜方式显著影响盆栽牡丹基质的水热效应,改善盆栽牡丹基质的微生态环境。春夏季盆口覆白膜加快植株叶色由红转绿,增强植株的光合性能与生理代谢,有利于秋季落叶期各部分生物量的积累。各覆膜方式下牡丹秋季壮苗指数表现为:T1>T5>T3>T2>T4>T0,说明上覆白膜对植株生长发育最有利。相关分析表明,根系发育状况与植株壮苗指数呈显著或极显著正相关。进一步通径分析表明,提高植株生物量及叶片光合性能是实现壮苗的基础。基于盆栽牡丹植株生长状况进行聚类分析,将6个处理组合聚为三类,其中T1和T5聚为一类,为优势处理。鉴于仅盆口覆白膜不仅苗体长势最优,而且劳动生产成本低,符合轻简高效栽培原则,建议盆栽牡丹生产上优先选择盆口上覆白膜的管理方式。

大花黄牡丹与日本牡丹杂交试验

大花黄牡丹(Paeonia ludlowii)是我国9个牡丹原生种之一,为西藏特有植物。挖掘大花黄牡丹的基因潜能,筛选优质杂交父本,可为进一步培育株型高大的黄色系牡丹新品种提供实践依据。以大花黄牡丹为母本,‘皇嘉门’('Kokamon')、‘芳纪’('Hoki')、‘岛大臣’('Shimadaijin')、‘日暮’('Higurashi')、‘新日月锦’('Shin-jitsugetu')、‘八千代椿’('Yachiyotsubaki')和‘花竞’('Hanakisoi')7个日本牡丹品种为父本进行杂交,测定结实率、饱满种子率和出苗率等指标。结果表明,从109朵杂交授粉花朵中,获得杂交种子219粒,饱满种子22粒,出苗10株,平均结实率为13.61%,平均饱满种子率为10.05%,平均出苗率为4.57%。7个日本牡丹品种与大花黄牡丹杂交均具有一定亲和性,杂交亲和性表现为‘新日月锦’>‘皇嘉门’>‘八千代椿’>‘岛大臣’>‘花竞’>‘芳纪’>‘日暮’。结合结实率和出苗率,以‘新日月锦’和‘八千代椿’2个品种为父本,杂交效果较佳。

‘海黄’牡丹香叶醇合酶基因PsGES的克隆及功能验证

[目的]探究植物释放的萜类化合物合成代谢的机理,为进一步解析牡丹萜类合酶基因家族的生物学功能提供理论依据。[方法]以芳香型牡丹品种‘海黄’(Paeonia×lemoinei‘High Noon’)为材料,根据转录组测序所得片段,克隆得到PsGES基因。同时利用瞬时表达方法将PsGES基因过表达载体注射进烟草叶片和‘凤丹’花瓣中验证基因功能。[结果]该结构基因的完整CDS序列长897 bp,编码298个氨基酸,氨基酸序列分析发现该蛋白具有较高的保守性,有1个保守结构域Terpene_cyclase_plant_C1。PsGES基因在盛开期花瓣中表达量最高且明显高于其他器官。亚细胞定位分析表明PsGES主要定位于叶绿体中。通过GC-MS方法可检测到烟草叶片和‘凤丹’花瓣中香叶醇的释放,同时烟草叶片和‘凤丹’花瓣中PsGES基因呈现高表达。[结论]本研究表明PsGES基因在植物体内调控香叶醇的合成。

牡丹病毒病研究进展

笔者纠正了“3种牡丹(芍药)病毒”的过时观点,统计、分析了国际上共计17种病毒侵染牡丹、芍药的情况,回顾了国内学者对牡丹、芍药病毒病的研究成果,包括对烟草脆裂病毒(tobacco rattle virus,TRV)侵染、为害牡丹、芍药的调查,近年来新发现的牡丹卷叶相关病毒(peony leafroll-associated virus,PLRaV)等多种侵染牡丹、芍药的新病毒,苹果茎沟病毒(apple stem grooving virus,ASGV)等已知病毒侵染牡丹、芍药的寄主新纪录,利用VIGS(virus induced gene silencing)技术研究牡丹、芍药基因功能等一系列研究。目前国内牡丹病毒病基础研究仍然存在多方面不足,如国家级课题专项资助机会少,对传统牡丹、芍药栽培中心病毒病发生本底情况不明,对病毒侵染、传播机制研究不深入等;在病毒病检测与诊断技术应用方面与西方国家相比存在明显的劣势,如基层的技术人员对病害诊断知识更新不及时,对病毒病的分子检测技术的最新发展了解不全面。由此提出应用分子检测技术开展全国范围的牡丹病毒病普查、开始牡丹病毒病的危险性分析和风险管理等有益建议。

覆膜对盆栽牡丹根际基质酶活性和微生物多样性的影响

覆膜能够改变植物根际土壤酶活性和微生物群落结构。本研究采用高通量测序和生物信息学方法,对春、夏两季覆膜和不覆膜盆栽牡丹根际基质的酶活性和微生物多样性变化进行测定与分析。结果表明,覆膜显著提高盆栽牡丹根际基质酶活性,中性磷酸酶活性变化最为显著,脲酶次之;改变了微生物群落结构组成和优势菌群相对丰度,芽单胞菌门(Gemmatimonadota)和变形菌门(Proteobacteria)的相对丰度有所提升,梭菌属(Faecalibacterium)和拟杆菌属(Bacteroides)的相对丰度发生变化;提高了根际微生物群落Alpha多样性,Simpson和Shannon指数均有所提高,但夏季覆膜降低菌群丰度;季节对微生物群落Beta多样性影响较大,覆膜有改变细菌距离的趋势。该研究结果可为进一步探讨覆膜对盆栽牡丹微生态环境的影响提供重要参考,为覆膜技术在盆栽牡丹生产中应用提供理论依据。

不同授粉方式对油用型牡丹结实性影响的研究

为提高油用牡丹产量,探索油用牡丹理想授粉方式,选择结实性良好、生长势强且自然花期相遇的常见油用型牡丹品种,开展自交、人工授粉、自然授粉等不同方式的授粉试验,调查其坐果率、结实率、种子千粒重等结实情况和蓇葖果单角大小、质量等果荚干物质性状。结果表明,油用型牡丹存在一定自花结实性,自交处理Ⅰ没有结实,处理Ⅱ3个品种结实,处理Ⅲ全部结实,其中‘凤丹白’结实最好,为每个果角0.54粒;将参试的牡丹品种进行4×4人工定向安全双列杂交,所有组合全部结实,平均坐果率高达92%,单果角结实率达到3.87粒,结实率最高的组合为‘凤丹白×景泰蓝’,单果角结实率达到6.96粒;田间自然授粉均有结实,‘凤丹白'结实率最高,3.19粒/个;‘景泰蓝’和‘凤丹白’杂交的种子千粒重较高,达到436.89 g;蓇葖果果荚大小和质量与杂交母本关系较密切,以‘景泰蓝’为母本时表现突出;通过不同授粉方式所对应的坐果率、结实率和复果荚重等指标综合分析,从高到低依次为:人工授粉>自然授粉>自交,母本是影响杂交成功率和果荚性状的重要因素;油用牡丹生产中可通过品种合理搭配间植、相互授粉,如‘景泰蓝’和‘凤丹白’,获得更高种子产量。

基于响应面法对皇冠牡丹(Paeonia×lemoinei‘Yellow Crown’)增殖培养基大量元素配方的优化

增殖系数低一直是制约牡丹微繁殖技术推广应用的障碍之一,但目前的研究多集中于植物生长调节剂的使用与组合,较少关注培养基配方对牡丹试管苗增殖效果的影响。本研究以皇冠牡丹(Paeonia×lemoinei‘Yellow Crown’)为试验材料,使用Design-Expert响应面法设计优化试验,探究WPM中5种大量元素[K_(2)SO_(4)、MgSO_(4)·7H_(2)O、KH_(2) PO_(4)、NH_(4) NO_(3)、Ca(NO_(3))_(2)·4H_(2)O]对皇冠牡丹试管苗增殖效果的影响,并建立数学模型分析预测最佳优化培养基配方。单因素效应分析结果表明,KH_(2) PO_(4)、NH_(4) NO_(3)与Ca(NO_(3))_(2)·4H_(2)O对牡丹试管苗的增殖效果有显著或极显著影响,而MgSO_(4)·7H_(2)O与K_(2)SO_(4)对牡丹试管苗的增殖效果无明显影响。交互作用分析结果表明,K_(2)SO_(4)与KH_(2) PO_(4)的交互作用对株高、茎长有显著或极显著影响,K_(2)SO_(4)与MgSO_(4)·7H_(2)O、KH_(2) PO_(4)与NH_(4) NO_(3)的交互作用对茎长有显著或极显著影响。根据试验数据构建模型进行分析预测,结果显示,5种大量元素优化配方为:K_(2)SO_(4)2257 mg/L、MgSO_(4)·7H_(2)O 907 mg/L、KH_(2) PO_(4)481 mg/L、NH_(4) NO_(3)200 mg/L与Ca(NO_(3))_(2)·4H_(2)O 1963 mg/L。在该条件下开展验证试验,获得试管苗的增殖系数、株高、茎长与叶片数分别为2.43、4.62 cm、1.30 cm、6.75张,略高于Design-Expert试验得出的预测值,显著优于对照组,说明本研究成功优化了皇冠牡丹的专用增殖培养基配方。研究结果不仅能大幅提高皇冠牡丹的增殖效率,也为其他牡丹品种增殖培养体系的构建与改良提供重要的技术参考。

油观两用牡丹新种质评价与筛选

建立科学合理的油观两用牡丹评价体系,为油观两用牡丹的推广应用提供科学依据。运用层次分析法(AHP)、灰色关联度分析(GRA)法对121个牡丹杂交植株的适应性、观赏性、油用性进行综合评价。层次分析法结果表明,5个杂交植株的综合评价得分在4.0以上,油用和观赏价值较高。灰色关联度分析结果表明,13个杂交植株的加权关联度在0.8以上,观赏价值较高,油用潜力较大。层次分析法和灰色关联度分析法筛选出4个相同的杂交植株。综上所述,运用层次分析法和灰色关联度分析法选出了FD×LYH-D2、FD×LYH-A1、FD×DHBZ-W3等14个可油观两用的新种质。

基于生长度日的牡丹物候期预测研究

利用2017-2019年在洛阳牡丹研究院开展的13个牡丹品种物候观测数据,结合逐日气象资料,分析了不同牡丹品种的物候特征,建立了基于生长度日的物候期模拟模型,再利用均方根误差(RMSE)和归一化均方根误差(NRMSE)对模型进行验证。结果表明:(1)牡丹鳞片开裂期、花蕾露出期的基点温度为3.6℃、翘蕾期、立蕾期、小风铃期、大风铃期、圆桃期、平桃期、破绽期的基点温度分别为5.6℃、6.8℃、7.8℃、8.6℃、8.8℃、12.9℃、13.4℃。(2)以此为依据,建立牡丹不同物候期发育的动态模拟模型。牡丹鳞片开裂期、花蕾露出期、翘蕾期、立蕾期、小风铃期、大风铃期、圆桃期、平桃期、破绽期的生长度日分别为13.8、14.3、12.8、12.8、13.5、14.2、59.5、10.3、10.1℃·d。(3)基于生长度日指标,结合气温资料模拟牡丹物候期,经检验,各物候期模拟值与实际值的均方根误差RMSE平均为2.6 d,归一化均方根误差NRMSE为3.3%,模型可适用于牡丹物候期的预测模拟。