Molecular phylogeny and maternal progenitor implication in the genus Kengyilia (Triticeae: Poaceae): Evidence from COXII intron sequences

Kengyilia is a perennial genus distributing in central and western Asia. Here, the levels of nucleotide diversity for COXII intron were obtained. The estimates of nucleotide diversity for different genome constitution ranged from θ = 0.00082 and π = 0.00082 for St genome species to π = 0.01227 and θ = 0.01229 for P genome species. Employing COXII intron sequences, the phylogenetic relationships within Kengyilia and between Kengyilia genus and its closely related genera were examined. The Maximum Parsimony analysis demonstrated that Kengyilia species were positioned into two clades corresponding to different maternal genomic donor. Kengyilia stenachyra, Kengyilia grandiglumis, Kengyilia hirsuta, Kengyilia melanthera, Kengyilia thoroldiana, Kengyilia alatavica and Kengyilia zhaosuensis were related to species of Agropyron, while Kengyilia kokonorica, Kengyilia rigidula, Kengyilia nana, Kengyilia mutica, Kengyilia longiglumis, Kengyilia laxiflora and Kengyilia gobicola were close to species of Roegneria and Pseudoroegneria. In addition, other three species of Kengyilia, such as Kengyilia batalinii, Kengyilia tahelacana and Kengyilia kaschgarica, were related to Douglasdeweya deweyi, Pseudoroegneria strigosa and Roegneria tibetica. This result indicated that there had been two phylogenetically divergent maternal donors within Kengyilia. Our new finding will help to understand the evolutionary history of the genus Kengyilia.     

Phylogeny and maternal donor of Kengyilia (Triticeae: Poaceae) based on chloroplast trnT–trnL sequences

The chloroplast DNA regions trnT–trnL was used to analyze to phylogenetic relationships and maternal donor of Kengyilia species and their closely related species. The Neighbor-Joining phylogenetic reconstructions partitioned the species into two reciprocally monophyletic groups. Kengyilia melanthera was related to species of Agropyron, whereas the other species were related to species of Pseudoroegneria and Roegneria. These results indicate that there have been at least two phylogenetically divergent maternal donors within Kengyilia, i.e. Agropyron (P genome) and Pseudoroegneria (St genome). In addition, the St genome of Kengyilia had several origins and diverse species of Pseudoroegneria might have taken part in the formation of polyploid species of Kengyilia.     

Molecular evolution and diversity of dimeric alpha-amylase inhibitor gene in Kengyilia species (Triticeae: Poaceae)

Kengyilia Yen et J. L. Yang is a group of allohexaploid species with StYP genomic constitutions in the wheat tribe. To investigate the evolution and diversity of dimeric alpha-amylase inhibitor genes in the Kengyilia, forty-five homoeologous DAAI gene sequences were isolated from sampled Kengyilia species and analyzed together with those of its close relatives. These results suggested that (1) Kengyilia species from Central Asia and the Qinghai–Tibetan Plateau had different origins from those of the geographically differentiated P genome; (2) the St and P genomes of Kengyilia were donated by Pseudoroegneria and Agropyron, respectively, and the Y genome had an independent origin and showed an affinity with the St genome; (3) purifying selection dominated the DAAI gene members and the St-DAAI gene was evolving at faster rate than the P- and Y-DAAI genes in Kengyilia; and (4) natural selection was the main factor on the codon usage pattern of the DAAI gene in Kengyilia.     

Taxonomic separation ofKengyilia (Poaceae: Triticeae) in relation to nearest relatedRoegneria,Elymus, andAgropyron,based on some morphological characters

Based on 100 species representative of the four genera, we scored 290 herbarium specimens for a number of morphological characters. The data were subjected to canonical discriminant analysis using characters different from those in the identification key to these genera byBaum, Yen, andYang (1991). These characters collectively support the four groupsAgropyron, Kengyilia, Roegneria, andElymus as previously defined. The four groups are also supported by the linear discriminant function with an overall rate of 83% correct classification. Length of lemma awn was found to be an additional diagnostic character asAgropyron andKengyilia have lemma awns shorter than 5 mm, whereasRoegneria andElymus have longer lemma awns with very few exceptions. Length of glume awns is also a useful supplementary generic diagnostic.Agropyron andElymus have glume awns, whereas the majority of species ofKengyilia and more than half of the species ofRoegneria lack them. If a glume awn is present it is usually not longer than 1 mm.     

Cytogenetic analyses inKengyilia laxiflora (Poaceae, Triticeae)

Kengyilia laxiflora (2n = 42) was cytogenetically studied with testersK. hirsuta (2n = 42, PPStStYY) andRoegneria kamoji (2n = 42, HHStStYY). Our data suggested thatK. laxiflora may possess a modified P genome, the P¹. Its St and Y genomes may also contain some structural changes and are more closely related to the St and Y genomes ofK. hirsuta than to those ofR. kamoji. Kengyilia laxiflora is reproductively separated from bothK. hirsuta andR. kamoji. These results indicated thatK. laxiflora is a good species in the genusKengyilia.     

Phylogenetic analysis of <Emphasis Type="Italic">Kengyilia</Emphasis> species based on nuclear ribosomal DNA internal transcribed spacer sequences

Phylogenetic analysis was conducted based on sequences of the internal transcribed spacer region (ITS) of nuclear ribosomal DNA in 17 species of Kengyilia, together with those of 18 species from Pseudoroegneria, Agropyron, Roegneria and Douglasdeweya by the maximum parsimony, maximum likelihood and neighbor-joining distance methods. The results indicate that species of Kengyilia had close affinities to species of Douglasdeweya and Agropyron. The species in Kengyilia was identified as two subgroups with regard to geographic distribution, indicating that species from the same distribution had a closer phylogenetic relationship. The genus Kengyilia was found as a ligament-group between Roegneria and Agropyron. The ITS sequence is a useful tool for studying the phylogeny of closely related species.     

Phylogenetic relationships among the species of <Emphasis Type="Italic">Elymus</Emphasis> sensu lato in Triticeae (Poaceae) based on nuclear rDNA ITS sequences

The genus Elymus L. sensu lato includes Roegneria, Elymus, Hystrix, Sitanion and Kengyilia, and they are very important group in the tribe Triticeae. However, the phylogenetic relationships and taxonomic status of them are still in dispute. The ITS sequences were obtained and analyzed for their phylogenetic relationships by using Maximum Parsimony (MP) and Bayesian Inference (BI) methods. The main results were as follows: (1) Most species in Roegneria, Elymus and Sitanion were clustered in the St clade with diploid St genome species, and it was difficult to distinguish the species in Roegneria and Elymus; (2) The polyploid species with St genomes in the St clade were divided into three groups, which suggests that there exists differentiation of St genome in polyploids; (3) Most species of Kengyilia have only P-type of clone and clustered with diploid Agropyron species, which may suggest that Kengyilia is a valid genus; (4) Hy. patula, the type species of Hystrix was clustered with species of Elymus, while Hy. duthiei ssp. duthiei, Hy. duthiei ssp. longearistata, Hy. coreana and Hy. komarovii were grouped with diploid Psathyrostachys species. It indicated that Hy. patula is distinct related to other Hystrix species, and it is reasonable to treat Hystrix patula as Elymus hystrix and other species in Hystrix should be transferred to Leymus; (5) The “clones bias” in ITS sequences are widespread in the allopolyploid species. The article is published in the original.     

Molecular and cytological evidences for the natural wheatgrass hybrids occurrence and origin in west China

Interspecies hybridization has been frequently observed in the tribe Triticeae. Natural hybridization between Kengyilia and Roegneria or Elymus species has not been reported as yet. Several sterile wheatgrass individuals exhibiting intermediately morphological traits between Kengyilia and Roegneria or Elymus species were identified in the meadow of Sichuan and Gansu provinces in China, suggesting their natural hybrid origin. The putative hybrids were analyzed by using the sequences of ITS and trnH-psbA together with cytological observation in order to assess the origin of hybrids. Both ITS and cytological data revealed the evidence of allopolyploid origin and confirmed the presence of StStYYP and StStYYHP genomes in the putative natural hybrids. The data suggest that the StStYYP hybrid originated from hybridization between Kengyilia and Roegneria and the hybrid with StStYYHP originated from hybridization between Kengyilia and Elymus. Chloroplast sequence data demonstrated that K. rigidula and K. melanthera were the likely maternal donors in the hybridization events.     

Heterospecific transformation of Pneumococcus and Streptococcus

Summary Transformations of two linked ribosomal loci (str and ery) were carried out between the SIII-1 strain of pneumococcus and the Challis and SBE strains of group H streptococcus. Transfer of markers between the Challis and SBE strains is as efficient as in the corresponding intrastrain transformations. Transfer between either of these strains and the pneumococcus, however, is less efficient than in the corresponding intrastrain transformation, and is referred to as heterospecific transformation. The inefficiency of the heterospecific transformation is due neither to specific lethality nor reduced uptake of heterologous DNA.When DNA was extracted from the hybrid resulting from a heterospecific cross and used to transform the original donor and recipient species, we found: (a) no donor material in the hybrid DNA responsible for the markedly low efficiency of integration into the recipient species; (b) donor material, in addition to the transforming marker itself, detectable by the higher efficiency with which hybrid DNA transforms the original donor species than does DNA from the original recipient species.DNA was extracted from each of 36 independently derived, doubly marked transformants resulting from the cross: Challis str-s ery-sxSIII-1 str-r53 ery-r2 DNA. Variability was observed between the different hybrid DNAs when the integration efficiency of the str marker in each DNA was compared with that of the ery marker. Variability of as great a magnitude was not observed when the same hybrid DNA was tested in repeated experiments, or when different DNA preparations were extracted from the same hybrid strain, or when several DNA preparations were obtained from a number of independent homospecific transformants. It is concluded that different kinds of donor material are present in the various hybrids, and that the nature of this extra-marker material affects the integration of the marker.Linkage of the str and ery markers was reduced in heterospecific transformations. The kind of donor DNA in the hybrid genome did not affect the linkage reduction observed when the str and ery markers were transferred back to the donor species in which they originated. Indeed, this linkage reduction was the same as that observed when the markers were originally transferred from the SIII-1 to the Challis strain. Specific factors reducing linkage in heterologous crosses must, therefore, be distinct from other factors which affect integration efficiency. The former, however, may be primarily responsible for the inefficiency of heterospecific transformation.One of the hybrid DNAs was used to obtain a second generation of hybrids by passing it through each of the original parental strains. Tests of the DNAs extracted from 24 independently produced, second-generation hybrids showed that hybrid DNA is subject to further alteration by a second integration involving some heterologous confrontation. The probability of such alteration appears to be increased if the second integration is accompanied by linkage reduction.Supported by NIH grant AI-00917.     

四种栎属青冈亚属植物叶绿体基因组特征及系统发育研究

栎属青冈亚属植物的系统发育地位长期存在着争议，部分种的种间关系不明确。为揭示宁冈青冈(Quercus ningangensis)、曼青冈(Q.oxyodon)、毛曼青冈(Q.gambleana)、竹叶青冈(Q.neglecta)的叶绿体基因组特征及系统发育关系，该研究选择以上4种栎属青冈亚属植物的成熟叶片进行二代测序，对其叶绿体基因组结构和特征进行分析，并结合相关类群进行系统发育研究。结果表明：(1)宁冈青冈、曼青冈、毛曼青冈、竹叶青冈的叶绿体基因组序列长度分别为160 906、160 883、160 832、160 784 bp,均编码133个基因，包括88个蛋白质编码基因、37个tRNA基因、8个rRNA基因。(2)4种栎属青冈亚属植物偏好以A/T结尾的密码子，质体基因组变异区域主要存在于非编码序列。(3)通过IR边界分析得出，4种栎属青冈亚属植物存在ycf1假基因且在IRb/SSC区域发生扩张。(4)系统发育分析显示，在壳斗科中，水青冈属(Fagus)和轮叶三棱栎属(Trigonobalanus)较早分化出来，栎亚属(subg.Quercus)未形成一个单系群，叶绿体基因组建树结...     

垂穗披碱草与达乌里披碱草基因组细胞遗传学比较

采用顺序FISH-GISH技术,12个重复序列探针,包括9个三核苷酸简单重复序列、2个卫星DNA重复序列pSc119.2和pAs1以及5S rDNA,通过重复序列的物理定位对达乌里披碱草和垂穗披碱草基因组中部分重复序列的分布特征进行了比较分析,为进一步研究垂穗披碱草和达乌里披碱草的物种形成及演化提供新的分子细胞遗传学证据。结果表明:(1)所有的序列在这2个物种的染色体上都能产生可检测的杂交信号,且在2个物种中(AAC)_(10)、(ACT)_(10)、(CAT)_(10)都表现为共分布,(AAG)_(10)与(AGG)_(10)表现为近似共分布;2个物种的H基因组除5S rDNA序列外,其他序列都产生强烈且丰富的杂交位点,St与Y基因组不同重复序列探针的荧光位点数目有所差别,表现为5S rDNA、pSc119.2、(AAC)_(10)、(CAT)_(10)、(ACT)_(10)、(CAC)_(10)探针的信号位点较少或无信号,其余的探针信号位点稍多。(2)达乌里披碱草的第2对染色体上具有(AAC)_(10)、(CAT)_(10)、(ACT)_(10)的杂交位点、第6对染色体上具有(CAC)_(10)的杂交位点,而在垂穗披碱草的St基因组中未观察到上述序列杂交位点;达乌里披碱草St基因组仅有第4对染色体的端部具有pSc119.2杂交位点,而在垂穗披碱草St基因组中的pSc119.2杂交位点位于第5对染色体长臂的间隔区;相对于达乌里披碱草,垂穗披碱草St和Y基因组染色体含有更多的重复序列杂交位点。(3)达乌里披碱草的H/Y基因组间易位在不同材料间是稳定存在的,达乌里披碱草基因组相对稳定,不同材料间H基因组重复序列杂交信号多态性高于St和Y基因组;垂穗披碱草基因组的变异较大,不同材料间St和Y基因组重复序列杂交信号多态性高于H基因组。研究认为,垂穗披碱草和达乌里披碱草的H基因组均起源于布顿大麦,St基因组可能起源于不同的拟鹅观草属物种;与达乌里披碱草相比垂穗披碱草St与Y基因组可能具有更高的染色体结构变异性,而垂穗披碱草St与Y基因组变异较大的原因可能是与同区域分布的含StY基因组的物种发生了种间渗透杂交。     

Genetic variation of the genus Kengyilia by ISSR markers

We investigated the genetic variation within 32 accessions distributed to 14 species and one variety by using ISSR (inter-simple sequence repeat) markers. The results showed that genetic variation was relatively higher among the accessions. A total of 593 bands were amplified by 12 ISSR primers, of which 535 bands (90.2%) were polymorphic. Eleven to 80 polymorphic bands were amplified from each prime, with an average of 44.6 bands. The interspecies GS (genetic similarity) value ranged from 0.430 to 0.866, and the average was 0.620. Cluster analysis showed that all accessions could be classified into 4 groups by ISSR markers. The different accessions in a species were clustered together, but they had genetic variation in molecular levels. There was obvious interspecies genetic variation. Species with similar morphological characteristics and from the same areas or neighboring geographical regions were clustered together and had close relationships. ISSR markers are useful in analyzing interspecies variation in Kengyilia. __________ Translated from Guihaia, 2006, 26 (4): 375–380 [译自: 广西植物]     

大鹅观草与蛇河披碱草属间杂种的细胞遗传学研究

为探讨大鹅观草(Roegneria grandis,2n=4x=28)的染色体组组成,为其正确的分类处理提供细胞学依据。该研究通过人工远缘杂交,成功获得3株大鹅观草与蛇河披碱草(Elymus wawawaiensis,2n=4x=28)属间杂种F1植株。杂种植株形态介于两亲本之间,不育。亲本及杂种经I2-IK溶液染色后进行花粉育性检测,结果显示Roegneria grandis和Elymus wawawaiensis的花粉可育,育性高达94.6%和90.5%;杂种F1不育。花粉母细胞减数分裂中期I染色体配对结果显示,亲本花粉母细胞配对正常,均形成14个二价体,以环状二价体为主,Roegneria grandis有频率很低(0.04/细胞)的单价体出现;杂种F1平均每个花粉母细胞形成6.46个二价体,变化范围为5~8;在观察的83个花粉母细胞中,有35.2%的花粉母细胞形成了7个二价体,形成6个二价体的细胞占42.59%,较少细胞形成8个二价体;平均每个细胞形成14.66个单价体,变化范围为10~18;平均每细胞观察到0.14个三价体;杂种花粉母细胞染色体构型为14.66 I+6.46 II+0.14 III;平均每细胞交叉数为9.83,C值为0.35。结果表明:(1)R.grandis与Elymus wawawaiensis有一组染色体组同源的St染色体组,另外一组染色体组不是St或者H染色体组,Roegneria grandis的染色体组组成不是St Stg;(2)较低频率的三价体(平均0.14个/细胞),可能是由于R.grandis的St和Y染色体组间具有一定的同源性,也可能是染色体易位等原因导致,对于Y染色体组的起源还需深入地研究;(3)在不同地理来源的披碱草属和鹅观草属物种中St染色体组同源性不同,R.grandis与来自于北美的Elymus lanceolatus与E.wawawaiensis的St染色体组较与分布于亚洲的E.sibiricus和E.caninus的St染色体组同源性反而更高,其原因还需要进一步地研究。     

黄藤染色体核型及基因组大小分析

为探究黄藤(Daemonoropsjenkinsiana)染色体核型和基因组的大小,采用体细胞染色体常规制片法与显微摄影技术相结合的方法,对黄藤染色体进行了核型分析,同时以番茄(Lycopersicon esculentum)为内标,应用流式细胞术对黄藤叶片基因组大小、DNA含量和DNA倍性进行了测定。结果表明,黄藤茎尖是理想的染色体制片材料;黄藤的染色体数为2n=24,核型公式为K(2n)=1M+17m+5sm+1st,核型类型为2C;核型不对称系数61.20%;黄藤的DNA含量为1.57 pg,基因组大小为1 539.53 Mb,黄藤的DNA倍性为二倍体(2n)。这是首次报道黄藤的核型和基因组大小,为深入开展黄藤属及其近缘属植物的核型和基因组比较分析提供了参考依据。     

Genomic distribution of retrotransposons 297, 1731, copia, mdg1 and roo in the Drosophila melanogaster species subgroup

The intragenomic distribution of five retrotransposon families (297, 1731, copia, mdg1 and roo) in the species of the melanogaster complex was studied by comparing results of the Southern blotting technique in males and females with those of in situ hybridization. The degree of structural polymorphism of each family in the different species was also investigated by restriction enzyme analysis. It was found that genomic distribution is a trait that depends on the family and species. The distribution of roo is mainly euchromatic in the four species and 1731 is heterochromatic, but the distribution of families 297, copia and mdg1 is markedly different in the melanogaster and simulans clades. These families were mainly euchromatic in D. melanogaster but heterochromatic in its sibling species. In the simulans clade most copia and mdg1 elements are located on chromosome Y. Differences in genomic distribution are unrelated with structural conservation. The relation of intragenomic distribution to phylogeny, transpositional activity and the role of the host genome are discussed.     

轮叶蒲桃叶绿体基因组特征及系统发育分析

轮叶蒲桃(Syzygium grijsii)系桃金娘科(Myrtaceae)蒲桃属(Syzygium)常绿灌木，其开发前景较好，但其叶绿体基因组特征及系统发育关系尚未有相关报道。为弥补轮叶蒲桃基因组学方面的空缺，该文对轮叶蒲桃的叶绿体基因组进行了系统的研究。运用Illumina高通量测序，并在GetOrganelle平台进行完整组装，同时利用组装好的数据分析轮叶蒲桃叶绿体基因组的结构特征和系统发育关系，其中包括轮叶蒲桃叶绿体基因组结构、功能及特征、密码子偏好性分析、叶绿体基因组的比较分析和系统发育的分析。结果表明：(1)轮叶蒲桃叶绿体基因组大小为158 591 bp,包含129个基因。其中，rRNA基因8个，tRNA基因37个，蛋白编码基因84个。分析检测到39个重复序列和84个SSR位点。(2)密码子偏好性分析发现轮叶蒲桃叶绿体基因组中末端存在对A/U的偏性，使用最多的是编码亮氨酸的密码子。(3)与近缘种比较，轮叶蒲桃的边界长度保守，边界处的基因种类与多个蒲桃属物种相似；轮叶蒲桃叶绿体基因组在LSC和SSC区变异度较大，有45处0.010i<0....     

长爪栘[木衣]叶绿体基因组特征系统发育及密码子偏好性分析

长爪栘[木衣](Docynia longiunguis Q.Luo & J.L.Liu)是我国特有的栘[木衣]属植物,具有较高的食药用价值.对其叶绿体基因组进行分析,有助于阐明栘[木衣]属内的系统发育关系,为长爪栘[木衣]资源的开发利用及进一步研究奠定基础.结合其近缘种云南移[木衣]叶绿体基因组数据,在进行全序列比对后...     

Effect of pollen source and pollen ploidy on endosperm formation and seed set in pseudogamous apomictic Paspalum notatum

 It is generally accepted that most angiosperms require an accurate balance between maternal and paternal genome contribution for endosperm development. The endosperm balance number (EBN) hypothesis postulates that each species has an effective number which must be in a 2:1 maternal to paternal ratio for normal endosperm development and seed formation. The aim of this work was to investigate the effect of different sources and ploidy levels of pollen donors on endosperm formation and seed production of aposporous tetraploid (2n=4×=40) Paspalum notatum. Hand-emasculated spikelets of an apomictic 4× plant were dusted with pollen of 2×, 4×, 5×, 6× and 8× races of the same species; 3× and 4× races of a phylogenetically closely related species, P. cromyorrhizon; and 2× and 4× races of P. simplex, a species of a different subgenus. Experiments including self-pollination as well as emasculation without pollination were conducted for controls. Results indicated that apomictic 4×P. notatum is a pseudogamous species with effective fertilization of the two unreduced (2n) polar nuclei by a reduced (n) sperm. Endosperm development and seed production occurred independently of the species or the ploidy level of the pollen donor. However, seed germination rates were significantly lower than in the self-pollinated control when the pollen donor was 3×P. cromyorrhizon or 2× and 4×P. simplex. Aposporous embryo sacs in Paspalum contribute to endosperm formation with two unreduced (2n) polar nuclei, while the male contribution is the same as in sexual plants (n). Since sexual Paspalum plants fit the EBN hypothesis, the EBN insensitivity observed in apomictic plants might be a prerequisite for the spread of pseudogamous apomixis. The EBN insensitivity could have arisen as an imprinting consequence of a high maternal genome contribution. Received: 20 February 1998 / Revision accepted: 21 October 1998     

The application of chloroplast DNA clones in identifying maternal donors for polyploid species of Stylosanthes

Organelle inheritance is strictly maternal for most plant species. This property makes organelle DNAs ideal material for identifying the maternal parents of polyploid species. A chloroplast DNA (cpDNA) clone from Stylosanthes was identified. Together with rice cpDNA clones, it was used in identifying putative maternal donors for polyploid Stylosanthes species. Of 15 taxa for which 2 or more accessions each were analysed, intra-taxon cpDNA variation was only identified within the diploid species S. viscosa. Of the nine basal diploid genomes identified, results from the cpDNA probes strongly suggested that Genome A1 is the maternal donor to S. aff. hamata, S. scabra, S. aff. scabra, S. sericeiceps and S. tuberculata and that it may also be the maternal donor to the hexaploid S. erecta; Genome C is the maternal donor to S. sp. A, S. mexicana, S. subsericea and S. sundaica; Genome E is the maternal donor to S. capitata. The maternal donor to S. fruticosa is likely to be Genome B3, and that to S. ingrata is likely to be Genome A1. The maternal donor to S. sympodialis, although similar to those of S. sp. genotypes, may not be included amongst the diploid taxa analysed in this study. The fact that none of the polyploid genotypes produced cpDNA fragments from more than one of their respective progenitors indicated that cpDNA in Stylosanthes is strictly maternally inherited. Received: 17 September 1999 / Accepted: 20 April 2000     

猴樟叶绿体基因组特征分析

猴樟(Cinnamomum bodinieri)枝叶含有丰富的精油,是重要的园林绿化树种和经济树种,但目前有关猴樟基因组学的研究报道不多。为揭示猴樟叶绿体基因组特征及系统发育关系,该文基于高通量测序平台进行测序,从头组装了完整的猴樟叶绿体基因组,并对其基因组结构、基因构成及序列重复、密码子使用偏好性以及系统发育进行分析,结合樟亚科主要属物种叶绿体基因组数据构建系统发育树。结果表明:(1)猴樟叶绿体基因组全长152 727 bp,包括一对20 132 bp的反向重复(IRs)区、93 605 bp的大单拷贝(LSC)区和18 858 bp的小单拷贝(SSC)区,总GC含量为39.13%。(2)该基因组共编码127个基因,包括83个蛋白质编码基因(PCGs)、36个转运RNA基因(tRNAs)和8个核糖体RNA基因(rRNAs); 共鉴定出92个SSR位点,其中大部分是A/T组成的单核苷酸重复序列; 密码子适应指数(CAI)为0.166,有效密码子数(ENc)为54.68; 猴樟与近缘种的叶绿体基因组主要在IR区和2个SC区边界上存在一定的差异。(3)24种樟亚科植物的系统发育树显示,猴樟与樟树亲缘关系最近,同时支持了樟属-甜樟属分支(Cinnamomum-Ocotea Clade)、月桂属-新木姜子属分支(Laurus-Neolitsea Clade)、润楠属-鳄梨属分支(Machilus-Persea Clade)的建立。该研究丰富了猴樟遗传资源信息,进一步确定了樟亚科主要属的系统发育地位。