重瓣榆叶梅全叶绿体基因组遗传特征分析

【目的】对重瓣榆叶梅Prunus triloba‘Multiplex’全叶绿体基因组序列进行测序,探究其系统发育位置并分析其叶绿体基因组成特点。【方法】以重瓣榆叶梅叶片为材料,采用2×CTAB法提取叶绿体DNA,利用Illumina NovaSeq平台进行叶绿体基因组的测序,组装、注释并分析其叶绿体基因组遗传特征。联合美国国家生物技术信息中心(NCBI)数据库数据,基于全叶绿体基因组序列构建了重瓣榆叶梅系统进化关系。【结果】重瓣榆叶梅叶绿体基因组全长为157827 bp,NCBI登录号MT937181,其结构为经典的四分体结构,由1个大单拷贝区域(LSC),1个小单拷贝区域(SSC)及反向重复区域(IRa/IRb)构成,其序列长度分别为86032、19023、26386 bp。GC和AT的总占比分别为36.80%和63.20%。重瓣榆叶梅的完整叶绿体基因组序列注释到132个基因,包括tRNA基因、编码蛋白基因、rRNA基因,分别为37、87、8个。重瓣榆叶梅叶绿体基因组共编码26678个密码子和236个符合条件的SSR位点。SSR位点中A/T碱基占优势,碱基偏好性十分明显。【结论】系统进化树分析表明,重瓣榆叶梅和榆叶梅P.triloba聚合成一分支结构,与同属植物长柄扁桃P.pedunculata亲缘关系较近。

榆叶梅叶绿体基因组特征分析

【目的】对榆叶梅(Amygdalus triloba)叶绿体基因组进行特征分析,并依据基因组序列数据构建系统发育树。【方法】通过Illumina HiSeq X Ten平台对榆叶梅叶绿体基因组进行序列测序、组装和基因注释,用生物信息学分析方法对其叶绿体基因组进行特征解析。【结果】研究发现榆叶梅叶绿体基因组大小和结构与经典被子植物相似。其蛋白编码基因共编码24 930个密码子,有29个偏好密码子。其中,亮氨酸密码子数目最多,占总量的10.56%。根据设置参数,发现榆叶梅叶绿体基因组中串联重复有15个。SSR(简单重复序列)大多位于基因间区IGS和LSC区域,位点有32个。【结论】榆叶梅与同亚属长柄扁桃(Amygdalus pedunculata)和李属(Prunus)毛樱桃(Prunus tomentosa)亲缘关系较近,但与同亚属的扁桃(Amygdalus dulcis)亲缘关系较远。

榆叶梅高效成熟胚培养成苗体系的建立

以榆叶梅(Prunus triloba Lindl.)成熟胚为外植体,构建榆叶梅稳定高效的胚培养成苗体系,测定萌发率、平均株高、生根率、平均数、平均根长、愈伤率和叶片形态等指标,设置MS、1/2 MS、WPM等3个基础培养基,筛选榆叶梅胚培养成苗的最适培养基;利用6-BA、NAA、IBA等3种植物生长调节剂和活性炭进行胚的萌发和生根试验,其中IBA、NAA均设0.05、0.1、0.2 mg/L等3个水平,6-BA设1、2 mg/L两个水平,统计胚萌发和生根情况,筛选榆叶梅胚培养成苗体系最佳培养基类型;在最适合榆叶梅胚培养生长培养基基础上,再设置不同低温处理时间(0、20、40、60、80 d)进行愈伤组织诱导及分化实验,统计愈伤率和叶片形态情况;最后分析不同子叶保留程度(完整子叶、1/2子叶和1/4子叶)对胚培养萌发和生根的影响。结果表明,MS培养基为榆叶梅胚的萌发和上胚轴生长的最适培养基;综合各项试验的最佳影响因子,榆叶梅在MS+6-BA 1.0 mg/L+IBA 0.1 mg/L+NAA 0.1 mg/L+活性炭500 mg/L培养基上萌发率和生根率最高,分别为83.33%、86.67%;4℃冷藏60~80 d为最适宜榆叶梅胚培养发育和正常生长的时间,冷藏时间80 d时萌发率达100%,生根率为93.33%,叶片绿色平展;保留完整子叶有利于促进上胚轴的伸长,保留1/4子叶有利于促进下胚轴的伸长。本研究筛选出最适宜榆叶梅胚的培养成苗培养基为MS+6-BA 1.0 mg/L+IBA 0.1 mg/L+NAA 0.1 mg/L+活性炭500 mg/L。

69个东北杏(Prunus mandshurica)无性系果实表型多样性及优良无性系筛选

【目的】深入探寻东北杏种质资源遗传多样性,筛选关键综合评价指标,提升育种效率,发掘优良东北杏无性系并高效利用。【方法】采用多样性分析、聚类分析、相关性分析和主成分分析,对69个东北杏无性系的45个果实表型性状(23个质量性状和22个数量性状)进行研究。【结果】41个表型性状变异系数大于0.1,数量性状的平均Shannon-wiener多样性指数(1.91)高于质量性状(0.62),数量性状的多样性较质量性状更丰富。聚类分析将69个东北杏无性系分为3类,A类适用于薄壳、出仁率高的品种类群;B类可用于选育高产、大仁型品种,属优良仁用杏品种类群;C类可作为高出核率和出仁率的重要育种材料。果肉薄、果小的无性系出核率更高;核壳薄、单核质量小的无性系出仁率更高;单核质量大的无性系产核量更高。5个主成分的累计贡献率达84.42%,能够反映22个数量性状的基本信息。结合相关性分析和主成分分析,22个数量性状可简化为果肉厚度、果纵径、单果质量、单核质量、单仁质量、出核率、出仁率、产核量共8个关键评价指标,筛选出10个果实经济性状表现优异的无性系。【结论】东北杏无性系的果实性状表现出丰富变异,经多指标综合评价筛选出的803、777、783、720、721、725、719、711、731和784号无性系可用于东北杏良种选育及开发利用。

榆叶梅栽培管理研究现状及进展

榆叶梅是我国特有的生态防护、园林绿化和油药兼用树种,对其合理的开发利用是亟待研究的重要课题。文中对榆叶梅的主要应用价值和栽培管理技术及相关研究现状进行分析阐述,以期对我国榆叶梅的资源开发利用起到一定推动作用。

外源钙对盐胁迫下榆叶梅幼苗生理特性的影响

以当年生榆叶梅幼苗为试验材料,研究了不同浓度氯化钙(5、10、15 mmol·L^(-1))对盐胁迫(0.4%浓度氯化钠)条件下榆叶梅幼苗生理特性的影响。结果表明:盐胁迫提高了榆叶梅幼苗SOD、POD活性,10 mmol·L^(-1)的氯化钙能够显著提高盐胁迫下两种保护酶活性,15 mmol·L^(-1)与10 mmol·L^(-1)处理之间无显著差异;盐胁迫降低了榆叶梅幼苗叶绿素含量,5 mmol·L^(-1)的氯化钙不会对盐胁迫下榆叶梅幼苗叶绿素含量产生显著影响,10 mmol·L^(-1)处理可显著提高盐胁迫下榆叶梅幼苗叶绿素含量;10 mmol·L^(-1)和15 mmol·L^(-1)的氯化钙均可以显著提高盐胁迫下榆叶梅幼苗净光合速率,5 mmol·L^(-1)处理对盐胁迫下榆叶梅幼苗净光合速率没有显著影响;盐胁迫提高了榆叶梅幼苗叶片内蔗糖磷酸合酶和蔗糖合成酶活性,10 mmol·L^(-1)氯化钙会显著降低盐胁迫下榆叶梅幼苗两种酶活性。综合分析认为,10 mmol·L^(-1)是缓解榆叶梅幼苗盐胁迫的适宜氯化钙浓度。

Selection of Suitable Area and Analysis of Adaptability Difference of Prunus humilis

This paper delves into and assesses the differences in biological traits and fruit nutritional composition of 3 varieties of Prunus humilis introduced from 2 different regions.Results showed that(i)the contents of protein,total sugar,and calcium of No.5 variety were higher those of the other 2 varieties,which was recognized as the most suitable variety for fresh fruit;(ii)the comparison of leaf areas index and fruit shape index of 3 varieties shows that the fruit shape index and individual fruit weight of the introduced varieties were higher than those of the control,the diameter of individual fruit of the introduced varieties higher than that of the control indicated that they had a higher fruit hardness,more dry matter accumulation and better fruit quality,and that the introduction region was more suitable for scale-up of P.humilis;(iii)there was a positive correlation with the number of fruiting branches and there was a significant negative correlation with individual fruit weight,while the leaf area had a significant negative correlation with the number of fruiting branches.The introduced varieties can develop normally in the 2 testing areas,notably,No.5 variety performed better than No.4 and No.6.Improving management is the prerequisite for maintaining proper number of fruiting branches and high yield.

Supervised Learning Method: Critical Analysis and Updating of Cubing Rate Formulas for Determining Bark Masses of Prunus africana (Hook. f.) Kalkman (Rosaceae) in Cameroon

The stem barks of Prunus africana are used in the treatment of the benign prostate. Cameroon is one of the important exporters of the barks. Despite the important measures adopted in Cameroon for sustaining its harvesting, some many chalenges still remain. The objective of this work is to refine the forest management parameters in relation to P. africana in the regions of Adamaoua and the South-West by developing a volume rate which makes it possible to estimate the production for a new stem. The work took place in two phases: in the South-West in 2010 and in Adamaoua in 2011. Data collection used the semi-direct method, while the cubing equation was deduced by the multiple linear regression method. Two models for volume estimation and three models for mass prediction were developed. The predictive parameters retained are diameter, height of the bole and thickness of the bark. Results show that the average mass of the dry bark for a given P. africana tree species is 27.55 ± 14.44 kg and this varies according to the site. The strong adjusted coefficient of determination (adjusted R2) observed illustrates the reliability of the proposed models. These models provide a reliable tool that can be adopted as a standard in Cameroon for P. africana.

榆叶梅育苗及园林应用技术

榆叶梅为蔷薇科、桃属,落叶灌木,是山西地区应用极为广泛的园林绿化植物。介绍了榆叶梅的生物学特性、播种育苗技术以及园林应用现状,为其在园林绿化中应用推广提供技术支持。

榆叶梅育苗及移栽管理技术

榆叶梅作为一种常见园林绿化植物,具有较高的观赏价值和经济价值。概述了榆叶梅的园林绿化功能、生物特征、生长习性,从种子采选、苗地选整、营养土配置3个方面,论述了榆叶梅育苗技术;从松土除草、间苗移栽、水肥管理、整形修剪、病虫害防治、越冬处理6个方面,论述了榆叶梅移栽管理技术,以供参考。

Molecular phylogeny and inflorescence evolution of Prunus(Rosaceae)based on RAD-seq and genome skimming analyses

Prunus is an economically important genus widely distributed in the temperate Northern Hemisphere.Previous studies on the genus using a variety of loci yielded conflicting phylogenetic hypotheses.Here,we generated nuclear reduced representation sequencing data and plastid genomes for 36 Prunus individuals and two outgroups.Both nuclear and plastome data recovered a well-resolved phylogeny.The species were divided into three main clades corresponding to their inflorescence types,-the racemose group,the solitary-flower group and the corymbose group-with the latter two sister to one another.Prunus was inferred to have diversified initially in the Late Cretaceous around 67.32 million years ago.The diversification of the three major clades began between the Paleocene and Miocene,suggesting that paleoclimatic events were an important driving force for Prunus diversification.Ancestral state reconstructions revealed that the most recent common ancestor of Prunus had racemose inflorescences,and the solitary-flower and corymb inflorescence types were derived by reduction of flower number and suppression of the rachis,respectively.We also tested the hybrid origin hypothesis of the racemose group proposed in previous studies.Prunus has undergone extensive hybridization events,although it is difficult to identify conclusively specific instances of hybridization when using SNP data,especially deep in the phylogeny.Our study provides well-resolved nuclear and plastid phylogenies of Prunus,reveals substantial cytonuclear discord at shallow scales,and sheds new light on inflorescence evolution in this economically important lineage.

Genome of tetraploid sour cherry (Prunus cerasus L.) ‘Montmorency’ identifies three distinct ancestral Prunus genomes

Sour cherry(Prunus cerasus L.)is a valuable fruit crop in the Rosaceae family and a hybrid between progenitors closely related to extant Prunus fruticosa(ground cherry)and Prunus avium(sweet cherry).Here we report a chromosome-scale genome assembly for sour cherry cultivar Montmorency,the predominant cultivar grown in the USA.We also generated a draft assembly of P.fruticosa to use alongside a published P.avium sequence for syntelog-based subgenome assignments for‘Montmorency’and provide compelling evidence P.fruticosa is also an allotetraploid.Using hierarchal k-mer clustering and phylogenomics,we show‘Montmorency’is trigenomic,containing two distinct subgenomes inherited from a P.fruticosa-like ancestor(A and A’)and two copies of the same subgenome inherited from a P.avium-like ancestor(BB).The genome composition of‘Montmorency’is AA’BB and little-to-no recombination has occurred between progenitor subgenomes(A/A’and B).In Prunus,two known classes of genes are important to breeding strategies:the self-incompatibility loci(S-alleles),which determine compatible crosses,successful fertilization,and fruit set,and the Dormancy Associated MADS-box genes(DAMs),which strongly affect dormancy transitions and flowering time.The S-alleles and DAMs in‘Montmorency’and P.fruticosa were manually annotated and support subgenome assignments.Lastly,the hybridization event‘Montmorency’is descended from was estimated to have occurred less than 1.61 million years ago,making sour cherry a relatively recent allotetraploid.The‘Montmorency’genome highlights the evolutionary complexity of the genus Prunus and will inform future breeding strategies for sour cherry,comparative genomics in the Rosaceae,and questions regarding neopolyploidy.

Chromosome-scale genome assembly of Prunus pusilliflora provides novel insights into genome evolution, disease resistance, and dormancy release in Cerasus L.

Prunus pusilliflora is a wild cherry germplasm resource distributed mainly in Southwest China.Despite its ornamental and economic value,a high-quality assembled P.pusilliflora genome is unavailable,hindering our understanding of its genetic background,population diversity,and evolutionary processes.Here,we de novo assembled a chromosome-scale P.pusilliflora genome using Oxford Nanopore,Illumina,and chromosome conformation capture sequencing.The assembled genome size was 309.62 Mb,with 76 scaffolds anchored to eight pseudochromosomes.We predicted 33035 protein-coding genes,functionally annotated 98.27%of them,and identified repetitive sequences covering 49.08%of the genome.We found that P.pusilliflora is closely related to Prunus serrulata and Prunus yedoensis,having diverged from them∼41.8 million years ago.A comparative genomic analysis revealed that P.pusilliflora has 643 expanded and 1128 contracted gene families.Furthermore,we found that P.pusilliflora is more resistant to Colletotrichum viniferum,Phytophthora capsici,and Pseudomonas syringae pv.tomato(Pst)DC3000 infections than cultivated Prunus avium.P.pusilliflora also has considerably more nucleotide-binding site-type resistance gene analogs than P.avium,which explains its stronger disease resistance.The cytochrome P450 and WRKY families of 263 and 61 proteins were divided into 42 and 8 subfamilies respectively in P.pusilliflora.Furthermore,81 MADS-box genes were identified in P.pusilliflora,accompanying expansions of the SVP and AGL15 subfamilies and loss of the TM3 subfamily.Our assembly of a high-quality P.pusilliflora genome will be valuable for further research on cherries and molecular breeding.

Post Debarking Response of Prunus africana (Hook. F) Kalkman (Rosaceae) Trees at Two Exploitation Sites in North Kivu (Eastern Democratic Republic of Congo)

Prunus africana is a species of great economic, medicinal and ecological importance. Due to its multiple uses, unsustainable exploitation methods and low regeneration capacity in tropical rainforests, this species is threatened with extinction. Present and exploited in the eastern part of DR Congo, knowledge of the dynamics of post-bark regeneration of Prunus africana remains fragmentary and poorly known. In North Kivu province, this species thrives in both afromontane forest and lowland tropical rainforest habitats. In order to contribute to the rational and sustainable exploitation of Prunus africana in this province, this paper was carried out with the objective of contributing to the knowledge of the dynamics of the regeneration of post-harvest bark of Prunus africana in two exploitation sites (low and high altitude). To achieve this objective, the inventory was conducted on 16 plots of 25 hectares each, with 8 plots per site. Dendrometric parameters (diameter at breast height (DBH), total tree height) and tree growth and regeneration parameters, i.e., stem bark thickness of the unharvested and harvested portions of the trees (bark reconstitution) were measured. A total of 716 barked stems of Prunus africana in 2016 in 25 hectares constituted the study sample. Results show that sites do not influence diameter at breast height of P. africana trees (p > 0.05) or total tree height. The bark diameter of harvested trees and the bark diameter of unharvested trees varied significantly by site (p 0.05). In contrast, the annual growth rate of bark differed with altitude;the highest rate was observed in trees growing at high altitude (2.97 ± 0.9 mm/yr) compared to 2.23 ± 0.74 mm/yr at low altitude. In view of these results, this study indicates that a half-rotation of 7 years could allow an effective reconstitution of the bark of Prunus africana at the second passage on the remaining side of the same stem.

紫叶李高接换种重瓣榆叶梅育苗技术

为有效缓解紫叶李库存量大市场过剩,重瓣榆叶梅树状花木市场紧俏供不应求等问题,拓宽树状花木培育和应用思路,在多年实践经验基础上,总结了紫叶李高接换种重瓣榆叶梅育苗技术,包括砧木选择、穗条选择、嫁接技术方法、嫁接后管理、树状花木培育等技术环节,以期为各地的重瓣榆叶梅树状花木生产提供技术支持。

桃(Prunus persica(L.) Batsch.)品种核心种质的构建与评价

为构建桃品种核心种质,通过对56份桃（Prunus persica（L.） Batsch.）初级核心种质的形态农艺性状数据（MOR）和SSR等位基因数据的分析,研究了不同聚类取样方法和完全随机取样方法下9种取样比例的遗传多样性指数、保留比例及各频率段等位基因的丢失比例。结果表明：聚类取样的方法优于完全随机取样,并以在80%的取样比例下MOR结合SSR数据聚类取样的效果最好,利用此方案构建的桃品种核心种质共包括45份材料,该核心种质的基因遗传多样性指数最高,保留了初级核心种质100%的形态农艺性状和96.6%的SSR等位基因,在出现频率低于0.05的等位基因中共丢失了2个等位变异,保留了出现频率在0.05-0.10的所有等位基因;利用6个数量性状对所构建的核心种质的代表性检测表明所构建的核心种质很好地代表558份桃原始种质的遗传变异。

普通杏(Prunus armeniaca)种质资源数量性状的遗传多样性分析

【目的】种质资源的遗传多样性研究是资源工作的核心，了解和掌握种质资源资源多样性，对于资源收集、管理、发掘、利用方面具有重要意义。【方法】对219份普通杏种质资源的11个性状进行了相关分析、主成分分析和聚类分析。【结果】普通杏种质资源各性状变异系数的变幅为15．7％。42．2％，其中可溶性固形物含量的变异系数最小，平均单果质量的变异系数最大。相关性分析得出：平均单果质量与叶柄长度、叶片长度和叶片宽度呈极显著正相关；可溶性固形物含量与可溶性糖呈极显著正相关：维生素C含量与可溶性固形物含量呈极显著正相关．与1a生枝粗度呈显著负相关。主成分分析结果表明：11个性状可以综合为4个主成分，前4个主成分累计贡献率达58．65％．第1主成分反映叶片因子，第2主成分反映枝条因子，第3、第4主成分反映的是品质因子。根据聚类分析把219份杏种质资源划分为6大类群：第1类种质群的主要特点是叶片较大：第Ⅱ类种质群的特点是果实品质性状较好．但是果实平均单果质量小；第Ⅲ类种质群的特点是果实平均单果质量大：第V类种质群的特点是果实品质好：第Ⅵ类种质群的特点是叶片较大且1a生枝又粗又长。【结论]普通杏种质资源的主要数量性状的变异较大，遗传多样性较丰富。

榆叶梅天然色素及其稳定性研究

以新疆地产榆叶梅花为实验材料 ,对榆叶梅花食用色素提取时间、提取温度、物料配比进行不同组合的对比实验研究 ;对光、热、pH值、还原介质、氧化介质、蔗糖、防腐剂、维生素和金属离子等对色素的稳定性影响进行了研究。结果表明 ,榆叶梅花色素为水溶性色素 ,属黄酮类色素。适用pH值范围较广 ,尤其酸性状态pH1～ 5最佳 ;蔗糖和防腐剂以及金属离子Zn2 +、Mg2 +、Ca2 +、K+、Na+对色素稳定性无不良影响 ;耐氧化剂与还原剂性能较差 ;而Fe2 +、Fe3+、Cu2 +、Sn2 +、Pb2 +对色素稳定性有一定影响 ,其颜色相反发生改变。

蔗糖、钙和硼对榆叶梅花粉离体萌发及花粉管生长的影响

研究了不同浓度蔗糖、钙（CaCl2）和硼（H3BO3）对单瓣榆叶梅（Prunus triloba var．simplex）和重瓣榆叶梅（Prunus triloba var．plena Dipp．）离体条件下花粉萌发和花粉管生长的影响。结果表明：5％～10％的蔗糖不利于花粉的萌发和花粉管生长，15％～30％的蔗糖能够提高花粉的萌发率和花粉管生长长度，其中25％的蔗糖为最适浓度，单瓣和重瓣榆叶梅相差不大，二者平均花粉萌发率和花粉管长度为38．72％和489．6um。0．01oA～0．07％的外源钙可以显著促进榆叶梅花粉的离体萌发和花粉管的生长，0．03％作用最大。0．01％的硼对单瓣榆叶梅，0．01%～0．03%的硼对重瓣榆叶梅花粉萌发和花粉管生长有显著的促进作用，重瓣榆叶梅比单瓣榆叶梅更需要外源硼的补充。

基于优化LDSS法的中国李(Prunus salicina)初级核心种质构建

核心种质的构建不仅能够提高种质资源的保存效率、方便资源管理,而且有利于种质资源的深入研究和种质创新。以国家果树种质熊岳李杏圃中保存的405份中国李为材料,依据46个农艺性状的鉴定数据,在按品种类群和杂交类型分组的基础上采用S策略和优化后的最小距离逐步取样法(ILDSS)经2次抽样构建出中国李初级核心种质。该核心种质样本集由97份种质材料组成,占总体样本比例约24%。对核心种质群体的代表性进行检测,结果表明该核心种质群体能够代表中国李原种质资源的遗传多样性及其群体结构。平均多态位点百分率、平均Nei’s遗传多样性指数、平均Shannon-Weaver多样性指数、极差符合率、变异系数变化率、均值差异百分率、方差差异百分率和主成分分析(散点分布图)等8项指标能够有效地评价核心种质的遗传多样性和代表性。