中国樟科润楠属植物一些种类修订

对中国樟科润楠属植物一些种进行了分类修订。随着研究工作的深入 ,发现过去发表的一些新种不能成立 ,应予合并 ,即嘉道理楠 =信宜润楠 ;长序润楠 =浙江润楠 ;密脉润楠 =刨花润楠 ;芳槁润楠 =黄心树 ;荔波润楠 =粉叶润楠。     

Divergent evolution of the chloroplast small heat shock protein gene in the genera Rhododendron (Ericaceae) and Machilus (Lauraceae)

BACKGROUND AND AIMS: Evolutionary and ecological roles of the chloroplast small heat shock protein (CPsHSP) have been emphasized based on variations in protein contents; however, DNA sequence variations related to the evolutionary and ecological roles of this gene have not been investigated. In the present study, a basal angiosperm, Machilus, together with the eudicot Rhododendron were used to illustrate the evolutionary dynamics of gene divergence in CPsHSPs. METHODS: Degenerate primers were used to amplify CPsHSP-related sequences from 16 Rhododendron and eight Machilus species that occur in Taiwan. Manual DNA sequence alignment was carried out according to the deduced amino acid sequence alignment performed by CLUSTAL X. A neighbour-joining tree was generated in MEGA using conceptual translated amino acid sequences from consensus sequences of cloned CPsHSP genes from eight Machilus and 16 Rhododendron species as well as amino acid sequences of CPsHSPs from five monocots and seven other eudicots acquired from GenBank. CPsHSP amino acid sequences of Funaria hygrometrica were used as the outgroups. The aligned DNA and amino acid sequences were used to estimate several parameters of sequence divergence using the MEGA program. Separate Bayesian inference of DNA sequences of Rhododendron and Machilus species was analysed and the resulting gene trees were used for detection of putative positively selected amino acid sites by the Codeml program implemented in the PAML package. Mean hydrophobicity profile analysis was performed with representative amino acid sequences for both Rhododendron and Machilus species by the Bioedit program. The computer program SplitTester was used to examine whether CPsHSPs of Rhododendron lineages and duplicate copies of the Machilus CPsHSPs have evolved functional divergence based on the hydrophobicity distance matrix. KEY RESULTS: Only one copy of the CPsHSP was found in Rhododendron. However, a higher evolutionary rate of amino acid substitutions in the Hymenanthes lineage of Rhododendron was inferred. Two positively selected amino acid sites may have resulted in higher hydrophobicity in the region of the alpha-crystallin domain (ACD) of the CPsHSP. By contrast, the basal angiosperm, Machilus, possessed duplicate copies of the CPsHSP, which also differed in their evolutionary rates of amino acid substitutions. However, no apparent relationship of ecological relevance toward the positively selected amino acid sites was found in Machilus. CONCLUSIONS: Divergent evolution was found for both Rhododendron lineages and the paralogues of CPsHSP in Machilus that were directed to the shift in hydrophobicity in the ACD and/or methionine-rich region, which might have played important roles in molecular chaperone activity.     

樟科润楠属植物ITS 序列贝叶斯分析及其系统学意义

应用nrDNA Internal Transcribed Spacer ( ITS) 序列, 使用Bayesian 分析法对樟科润楠属的系统学问题进行了初步探讨, 结果表明润楠属在鳄梨属群中本身作为一独立分支, 是一个自然的单系类群; 由于其花被裂片果期宿存且强烈反转与同产自亚洲的楠属和油丹属存在清晰界线。本研究否定了前人依据花被片外面被毛情况及果实大小所建立的润楠属属下系统, 但同时暗示着花序类型可能是解决润楠属下系统演化的关键性状。本研究对解决润楠属属内种间的系统演化关系尚有不足, 建议今后补充更多的属内物种以及寻找新的分子标记进行更深入的研究。     

樟科润楠属植物ITS序列贝叶斯分析及其系统学意义

应用nrDNA Intemal Transcribed Spacer（ITS）序列,使用Bayesian分析法对樟科润楠属的系统学问题进行了初步探讨,结果表明润楠属在鳄梨属群中本身作为一独立分支,是一个自然的单系类群;由于其花被裂片果期宿存且强烈反转与同产自亚洲的楠属和油丹属存在清晰界线。本研究否定了前人依据花被片外面被毛情况及果实大小所建立的润楠属属下系统,但同时暗示着花序类型可能是解决润楠属下系统演化的关键性状。本研究对解决润楠属属内种间的系统演化关系尚有不足,建议今后补充更多的属内物种以及寻找新的分子标记进行更深入的研究。     

关于樟科润楠属和鳄梨属的分类界线问题

讨论了润楠属Machilus Nees与鳄梨属Persea Mill.的分类界线, 认为两属的主要区别如下: 在润楠属中, 花被裂片相等或近相等, 极少外轮明显短于内轮, 在果期为纸质, 极少为薄革质, 伸长, 强度反曲, 极少张开与不反曲, 几乎宿存, 极少脱落, 如果脱落时则内、外轮从基部完全脱落; 花柱早落; 分布亚洲热带及亚热带地区。而在鳄梨属中, 花被裂片极不相等, 外轮明显短于内轮, 很少近相等, 在果期为革质到木质, 很少为薄革质, 张开或直立, 几乎不反曲, 绝大部分宿存或内轮在距基部的1/3到1/2处脱落; 花柱有时宿存; 分布美洲。两属的界线清楚, 不宜合并。把产于越南北部的Persea balansae Airy Shaw和产于苏门答腊的P. sumatrana Kosterm.转移到Machilus中, 从而提出Machilus balansae (Airy Shaw) F. N. Wei &; S. C. Tang和M. sumatrana (Kosterm.) F. N. Wei &; S. C. Tang两个新组合。     

海南岛润楠属一新种

描述了海南润楠属(樟科)一新种,即文昌润楠     

福建润楠属一新种

描述了福建润楠属(樟科)一新种,即汀州润楠。     

中国樟科四个名称的发表日期考订

对中国樟科4个种名多脉楠Machilus polyneura Chang、十万大山楠Machilus shiwandashanica Chang、猪脚楠Machilus cathayensis Chun ex Chang和糠秕琼楠Beilschmiedia furfuracea Chun ex Chang的研究发现, 它们的合格发表日期是1963年, 而不是1960年。     

中国及越南樟科润楠属植物一些种类的修订

报道了产自中国和越南的樟科润楠属的4个种的修订结果,即:MachiluslongipedicellataH.Lec.为M.yunnanensisH.Lec.的异名;M.thunbergiiSieb.etZucc.var.condorensisH.Lec.为M.lohuiensisS.Lee的异名,而其中被H.Liou误定的Poilane13161号则为M.cicatricosa;过去被中国学者误当作M.longipedicel-lata的西藏及云南中部至西北部的部份标本是广泛分布于喜马拉雅地区的M.duthieiKingexHook.f.。     

国产樟科楠属五种植物之分类修订

根据分子系统学研究结果,楠属（Phoebe）中以其宿存的花被片在果时松散、先端外倾,果实球形为特征的物种,即山楠Phoebe chinensis Chun,小花楠P．minutiflora H．W．Li,竹叶楠P．faberi（Hemsl．）Chun,小叶楠Pmicrophylla H．W．Li以及长毛楠P．forrestiiW．W．Smith均应归入润楠属（Machilus）,其中原先作为润楠属物种发表的竹叶润楠Machilus faberi Hemsl．应予采用,但山楠一种其种加词发表时已是晚出同名,另起新名为Machilus montana L．Li,J．Li＆H．W．Li,nom．nov,而余下三种作为新组合在此发表,即：M.minutiflora（H．W．Li）L．Li,J．Li＆H．W．Li,comb．nov．;M．microphylla（H．W．Li）L．Li．J．Li＆H.W．Li,comb．nov．及Mforrestii（W．W．Smith）L．Li,J．Li＆H_W．Li,comb．nov．。     

浙江省红楠生境地群落数量分类和环境解析

为探讨群落结构与环境因子对红楠Machilus thunbergii在浙江省分布及发展的影响,采用双向指示种分类(TWINSPAN)、典范对应分析(CCA)并结合种间联结分析,对浙江省172个红楠生境地群落进行数量分类排序与环境解析。结果表明:(1)TWINSPAN将172个样地群落分成8个群落类型,红楠在群落中为优势种或主要伴生种。群落类型的不同是影响红楠生长及更新的重要原因。(2)海拔高度及坡度是决定红楠分布及发展的主导环境因子。红楠作为优势种的生境地主要特征为海拔900m以下、坡度35°以下。(3)甜槠(Castanopsis eyrei)、青冈(Cyclobalanopsis glauca)、木荷(Schima superba)为群落中的稳定优势种,种间联结结果显示与红楠均为显著正关联。     

国产润楠属植物的叶表皮特征及其系统学意义

对45种国产润楠属(Machilus Nees)植物的叶表皮进行光学显微镜和扫描电镜观察,其中31种为首次报道.结果表明:润楠属植物叶表皮细胞形状为多边形或不规则形,气孔复合体均为平列型且仅分布在下表皮;上下表皮细胞的垂周壁式样有5种类型:平直、圆滑、浅波、波状、平直-弓形;下表皮毛被有(稀疏、密集或非常密集)或无;上表皮平周壁纹饰类型有:点状、平滑、条纹(或波浪条纹);下表皮内面平周壁纹饰类型有:不规则、平滑、粗糙网状、微毛状、颗粒状、鳞片状.这些特征在本属种间存在较显著的差异,可作为区分种类的辅助特征和种间亲缘关系,因而对润楠属植物的分类学研究和亲缘关系的确定有较大意义.     

香港润楠属植物的分类研究

本文记载了香港润楠属植物共１１种,其中包括２个香港新记录（Ｍ．ｌｅｐｔｏｐｈｙｌａＨａｎｄ．－Ｍａｚ．,Ｍ．ｒｏｂｕｓｔａＷ．Ｗ．Ｓｍ．）,改正了４个过去被误定的植物种名。     

模拟酸雨对刨花楠幼苗生长和光合生理的影响

研究了模拟酸雨对亚热带典型用材树种和经济树种刨花楠(Machilus pauhoi)幼苗生长和光合生理的影响,以期为浙江省引种刨花楠提供科学依据.结果表明,pH4.0的模拟酸雨对刨花楠株高、地径和叶绿素含量无明显影响,而pH2.5的模拟酸雨使株高显著降低;pH为4.0的模拟酸雨对刨花楠的光合参数无显著影响,而pH为2.5的酸雨处理则能明显提高刨花楠的胞间CO2浓度、暗呼吸速率以及光补偿点、增加气孔导度和蒸腾速率,显著降低最大净光合速率;相关分析和回归分析表明,酸雨增加了刨花楠对环境的敏感性.     

樟科两个近缘属润楠属和楠木属花粉形态的比较研究

通过扫描电镜观察对樟科润楠属13个种和近缘属楠木属5个种的花粉形态进行了比较研究。结果显示:两个属的花粉均属鳄梨型,即:花粉粒辐射对称、无极性、球形,外壁具明显的刺、薄壁区或小穿孔,通常刺小而密集。首次报道了润楠属与楠木属有的种类如Machilusyunnanensis、M.litseifolia、Phoebepandulata和Ph.zhennan等植物的花粉有圆形垫状隆起。两个属花粉形态的微观差异主要表现在小刺的长度、刺基部是否膨大以及垫状隆起的类型等方面。还讨论了这两个近缘属在花粉微观形态的多样性及其系统学意义。     

Taxonomic Revision of Five Species of the Genus Phoebe (Lauraceae) from China

On the basis of molecular phylogenetic analyses of the Persea group (Lauraceae) using the sequences of ITS and LEAFY intron II, the species Phoebe chinensis Chun, P.minutiflora H. W. Li, P.faberi (Hemsl.) Chun, P.microphylla H. W. Li and P.forrestii W. W. Smith, which are characterised by the persistent perianth lobes loosely clasping the base of fruit, apex extrorse, as well as globose fruit, were transferred into the genus Machilis. Accordingly, a new name Machilus montana L. Li, J. Li & H. W. Li, as well as three new combinations M.minutiflora (H. W. Li) L. Li, J. Li & H. W. Li, M.microphylla (H. W. Li) L. Li, J. Li & H. W. Li and M.forrestii (W. W. Smith) L. Li, J. Li & H. W. Li were reported here.     

润楠属广布种和狭域种幼苗生理生态特征

润楠属植物属于基部被子植物类群,大部分物种局限分布于热带亚热带森林的潮湿生境,但也有些物种分布范围较广。本研究以润楠属11个物种的幼苗为材料,测定了一系列植物叶片水力学性状和解剖结构,包括:比叶重、叶片密度、气孔密度、叶脉密度、膨压丧失点水势、栅栏组织和海绵组织厚度等。结果表明:与其它分布在热带亚热带地区的被子植物相比,润楠属植物的叶脉密度较低,推测叶脉密度受强烈的进化限制;该属植物叶脉密度与气孔密度、栅栏和海绵组织的比值呈显著的正相关,表明该属植物能够维持叶片水平的水分供需平衡;广布种比狭域种具有更低的叶片膨压丧失点和更高的叶片密度,耐旱能力更强,但是比叶重差异不显著;叶片的膨压丧失点与物种的最大树高呈反比,即更高的物种叶片耐失水能力更强,说明植物叶片耐旱性与植物本身的遗传特性有关。本研究结果显示,叶片水力学性状可以较好地用于解释润楠属植物的地理分布。     

Correlation and regression studies between pupal weight and fecundity of muga silkworm Antheraea assama Westwood (Lepidoptera: Saturniidae) on four different foodplants.

Female pupal weight and fecundity of mother moth of Antheraea assama Westwood fed with four different food plants have been studied. Litsaea polyantha fed females showed significantly higher pupal weight and higher rate of oviposition in comparison to three food plants Machilus bombycina, Litsaea salicifolia and Cinnamomum glaucescens. The number of eggs laid was correlated with the pupal weight. The correlation co-efficient (r = 0.9730) showed positive and significant correlation at 1% level. The pupal weight was found to be the best and genuine estimator of fecundity.     

浙江天童国家森林公园常绿阔叶林种间相关的研究

应用Ｘ２检验、联结系数ＡＣ、点相关系数ＰＣＣ和Ｐｅａｒｓｏｎ相关系数ｒ正公式研究了浙江天童国家森林公园常绿阔叶林植物的种间相关,将所测定的乔木层和灌木层植物分别划分为２个种组,即乔木层木荷＋苦槠组和青冈＋红楠组;灌木层木荷幼树＋　木组和红楠幼树＋长果桂幼树组．