一种油茶新炭疽病原的多基因系统发育分析鉴定

为明确我国油茶炭疽病病原菌的种类,对采集自我国6个省市油茶产区的炭疽病样本进行病原菌分离,通过形态学特征并结合多基因谱系分析方法构建系统发育树进行比较分析.结果表明共分离到能引起油茶叶出现炭疽病症状的病原菌23株.病原菌在PDA培养基上28 ℃培养7 d后,菌落圆形,初期白色,逐渐变为灰色,最终为灰黑色;分生孢子堆橘黄色,分生孢子椭圆形、单胞、无色,大小为(16.8±0.7) μm×(5.7±0.4) μm;菌丝附着孢椭圆形,褐色,边缘光滑、完整,大小为(9.5±1.5) μm×(6.1±0.6) μm.多基因系统发育树显示,这23株病原菌与包括模式菌株ICMP 18581在内的所有果生刺盘孢菌Colletotrichum fructicola菌株序列聚为一个进化枝,置信度高达100%.根据形态特征及多基因系统发育树,鉴定这23株病原菌为果生刺盘孢菌C.fructicola,为国内油茶上果生刺盘孢菌的首次报道.     

利用trnL—F序列分析杨属树种的系统发育关系

对杨属4个派17个主要栽培树种及杂种共26个雌雄单株进行了叶绿体trnL-F间隔区序列的PCR扩增、回收和纯化,并分别克隆到pGEM-T载体中进行序列测定。结果表明:在杨树中基因trnL-F间隔区序列的长度为771～811bp,G+C含量为30.6%～31.9%;排序后的比对长度为857个位点,其中46个为变异位点,33个为系统发育的信息位点。以嵩柳和极地柳为外类群,分别用邻接法和UPGMA方法构建了杨属主要栽培树种的系统发育进化树。系统进化分析显示:1)白杨派能聚类形成一个单独分支,而黑杨派亚支与青杨、胡杨派亚支聚类形成另外一个主要的分支,其中胡杨派和青杨派不能区分开;2)青杨派的藏川杨独立于杨属其他种形成一个单独分支,而冬瓜杨却与白杨派聚类在一起;3)白杨派为单系起源,黑杨派和青杨派为多系起源,胡杨派可能也是多系起源。研究结果在分子水平上为杨属树种的起源和系统进化研究提供了证据,具有重要的理论意义和潜在的实践价值。     

基于线粒体COI基因序列的挂墩稻弄蝶分类地位研究

对稻弄蝶属Parnara4种20个样本的线粒体COI基因序列(1380 bp)的特征、遗传距离进行了分析,并以2种谷弄蝶Pelopidas为外群,采用最大简约法(MP)和贝叶斯法(BI)构建系统树.结果表明:种间最小序列差异为3.3%,种内个体间最大序列差异为0.9%;系统树显示挂墩稻弄蝶Parnara batta与直纹稻弄蝶Parnara guttata是2个明显不同的分支;其种间的平均遗传距离为3.5%.综合地理分布与形态差异,挂墩稻弄蝶应该是一个独立的种.     

Phylogeny and systematics of the genus Calonectria

Species of Calonectria are important plant pathogens, several of which have a worldwide distribution. Contemporary taxonomic studies on these fungi have chiefly relied on DNA sequence comparisons of the β-tubulin gene region. Despite many new species being described, there has been no phylogenetic synthesis for the group since the last monographic study almost a decade ago. In the present study, the identity of a large collection of Calonectria isolates from various geographic regions was determined using morphological and DNA sequence comparisons. This resulted in the discovery of seven new species; Ca. densa, Ca. eucalypti, Ca. humicola, Ca. orientalis, Ca. pini, Ca. pseudoscoparia and Ca. sulawesiensis, bringing the total number of currently accepted Calonectria species to 68. A multigene phylogeny was subsequently constructed for all available Calonectria spp., employing seven gene regions, namely actin, β-tubulin, calmodulin, histone H3, the internal transcribed spacer regions 1 and 2 and the 5.8S gene of the ribosomal RNA, 28S large subunit RNA gene and translation elongation 1-alpha. Based on these data 13 phylogenetic groups could be distinguished within the genus Calonectria that correlated with morphological features. Dichotomous and synoptic keys to all Calonectria spp. currently recognised are also provided.Taxonomic novelties: New combinations - Calonectria angustata (Crous & El-Gholl) L. Lombard, M.J. Wingf. & Crous, Ca. australiensis (Crous & H.D. Hyde) L. Lombard, M.J. Wingf.& Crous, Ca. canadensis (J.C. Kang, Crous & C.L. Schoch) L. Lombard, M.J. Wingf. & Crous, Ca. chinensis (Crous) L. Lombard, M.J. Wingf. & Crous, Ca. citri (H.S. Fawc. & Klotz) L. Lombard, M.J. Wingf. & Crous, Ca. curvata (Boedijn & Reitsma) L. Lombard, M.J. Wingf. & Crous, Ca. curvispora (Crous & D. Victor) L. Lombard, M.J. Wingf. & Crous, Ca. ecuadoriae (Crous& M.J. Wingf.) L. Lombard, M.J. Wingf. & Crous, Ca. gordoniae (Leahy, T.S. Schub. & El-Gholl) L. Lombard, M.J. Wingf. & Crous, Calonectria hawksworthii (Peerally) L. Lombard, M.J. Wingf. & Crous, Calonectria hurae (Crous) L. Lombard, M.J. Wingf. & Crous, Calonectria indonesiae (Crous) L. Lombard, M.J. Wingf. & Crous, Ca. leucothoës (El-Gholl, Leahy & T.S. Schub.) L. Lombard, M.J. Wingf. & Crous, Ca. malesiana (Crous) L. Lombard, M.J. Wingf. & Crous, Ca. multiphialidica (Crous, Simoneau & Risède) L. Lombard, M.J. Wingf. & Crous, Ca. pacifica (J.C. Kang, Crous & C.L. Schoch) L. Lombard, M.J. Wingf. & Crous, Ca. penicilloides (Tubaki) L. Lombard, M.J. Wingf. & Crous, Ca. pseudonaviculata (Crous, J.Z. Groenew. & C.F. Hill) L. Lombard, M.J. Wingf. & Crous, Ca. sumatrensis (Crous) L. Lombard, M.J. Wingf. & Crous. New species - Ca. densa L. Lombard, M.J. Wingf. & Crous, Ca. eucalypti L. Lombard, M.J. Wingf. & Crous, Ca. humicola L. Lombard, M.J. Wingf. & Crous, Ca. orientalis L. Lombard, M.J. Wingf. & Crous, Ca. pini L. Lombard, M.J. Wingf. & Crous, Ca. pseudoscoparia L. Lombard, M.J. Wingf. & Crous, Ca. sulawesiensis L. Lombard, M.J. Wingf. & Crous.     

橘小实蝇分子系统发育研究进展

橘小实蝇[Bactrocera(Bactrocera)dorsalis(Hendel)]是一种世界危险性检疫害虫,寄主范围广,能为害250多种瓜果蔬菜,给果蔬业带来严重的经济损失。本文综述了同工酶电泳、RFLP、核酸序列分析、微卫星分析及基因芯片技术等分子生物学技术在橘小实蝇分子系统发育方面的研究进展,并探讨了橘小实蝇分子系统发育研究中存在的问题和发展方向。     

Improving Potato virus Y strain nomenclature: lessons from comparing isolates obtained over a 73‐year period

Biological and whole genome properties were compared between eight historical European (1943–1984) and five Australian (2003–2012) Potato virus Y (PVY) isolates. Based on eliciting hypersensitivity genes Nc, Ny or Nz, the former belonged to biological strain groups PVY^C (CT, CRM1), PVY^O (CRN, KE, RS) or PVY^Z (CM2, CRM2, DS). The latter were inoculated to differential and other potato cultivars, tobacco and tomato. Two belonged to PVY^O (BL, DEL3), one to PVY^Z (ATL1), and one (KIP1) to suggested strain group (PVY^D) which elicited putative hypersensitivity gene Nd. Tomato isolate CN1 (and unsequenced CN2), which were poorly adapted to infect potato, were not grouped. Next‐generation sequencing (NGS) of samples containing all isolates except CN2, yielded 13 complete sequences of 9592–9700 nucleotides (nt), and one partial sequence of 9002 nt, none being recombinants. Comparing the former with 60 other PVY complete genomes, found one (CRM2) in phylogenetic subgroup Y^O, eight in Y^O5 (CM2, CRN, DS, KE, RS, ATL1, BL, DEL3), three in Y^C2 (CRM1, CT, KIP1) and one in Y^C1 (CN1). Thus, biologically defined PVY^O (5) and PVY^Z (4) isolates were within phylogenetic subgroups Y^O or Y^O5, biological PVY^C isolates (2) within Y^C2, biological PVY^D isolate KIP1 in Y^C2 and tomato isolate CN1 in Y^C1. NGS identified KIP1 and partial sequence KIP from mixed infection. KIP was in Y^O5. Grouping of four PVY^Z isolates within phylogenetic PVY^O, and the PVY^D isolate within phylogenetic PVY^C, reveals disagreement between current biological and phylogenetic PVY nomenclature systems. Using Latinized numerals for phylogenetic group names resolved this.     

2株节旋藻的分类鉴定和磷脂脂肪酸特征分析

利用荧光显微镜观察节旋藻CB001和CB002的菌丝形态,同时对其16S rDNA序列以及在液体和固体培养条件下的磷脂脂肪酸特征进行系统分析.显微成像观察表明,CB001和CB002均属于钝顶节旋藻(Arthrospira platensis),具有运动能力;磷脂脂肪酸特征分析结果显示,磷脂脂肪酸16∶0、16∶1 w7c、18∶1w9c、18∶2 w6c、14∶0 anteiso和16∶1 w7c alcohol可能是节旋藻的代表性脂肪酸;18∶1 w5c和16∶3 w6c分别为CB001和CB002的特有磷脂脂肪酸组分;同时,不同培养方式对CB001和CB002磷脂脂肪酸组成模式具有极其显著的影响.     

Identification and Bioinformatics Analysis of SnRK2 and CIPK Family Genes in Sorghum

Through bioinformatic data mining, 10 SnRK2 and 31 CIPK genes were identified from sorghum genome. They are unevenly distributed in the sorghum chromosomes. Most SnRK2 genes have 8 introns, while the CIPK genes have a few （no intron or less than 3 introns） or more than I0 introns. Phylogenetic analysis revealed that SnRK2 genes belong to one cluster and CIPK genes form the other independent cluster. The sorghum SnRK2s are subgrouped into three parts, and CIPK into five parts. More than half SnRK2 and CIPK genes present in homologous pairs, suggesting gene duplication may be due to the amplification of SnRK family genes. The kinase domains of SnRK2 family are highly conserved with 88.40% identity, but those of the CIPK family are less conserved with 63.72% identity. And the identity of sorghum CBLinteracting NAF domains of CIPKs is 61.66%. What＇s more, regarding to the sorghum SnRK2 and CIPK kinases, they are characterized with distinct motifs and their subcellular localization is not necessarily the same, which suggests they may be divergent in functions. Due to less conserved sequences, complex subcellular localization, and more family members, sorghum CIPK genes may play more flexible and multiple biological functions. According to the phylogenetic analysis of SnRK genes and SnRK functional studies in other plants, it is speculated that sorghum SnRK2 and CIPK genes may play important roles in stress response, growth and development.     

黄瓜NRT3基因的鉴定和特征分析

旨在探讨黄瓜NRT3基因的遗传进化和功能,为进一步研究黄瓜NRT3基因的功能提供依据。利用生物信息学方法,从黄瓜基因组中鉴定出2个NRT3基因,并对这些基因的基因组分布、结构、遗传进化和顺式元件进行了系统分析。结果显示,黄瓜的NRT3两个基因均位于1号染色体,具有1个或者2个外显子,分别与拟南芥的NRT3.1或者NRT3.2直系同源。NRT3在瓜类作物间编码蛋白的序列非常保守,它们都具有数个植物激素和逆境应答元件,而且黄瓜和甜瓜的直系同源NRT3基因的顺式调控元件存在较大差异。本研究为进一步研究黄瓜NRT3的遗传进化和功能提供了线索。