澳门路环华润楠古树的物候及所属群落特征

为加强对澳门华润楠(Machilus chinensis)的保育工作,对最古老的1株华润楠和群落优势种绒毛润楠(M.velutina)进行物候监测,并采用样地调查法对群落的物种组成、结构和物种多样性进行了分析。结果表明,2—3月为华润楠新叶生长盛期,3月中下旬为花期,果期由4月持续到9月;4—5月为绒毛润楠展叶盛期,10—12月为花期,12月至翌年3月为果期。2 000 m²的样地中共记录到维管植物104种,隶属于48科82属。种子植物区系以热带分布为主,占总区系成分的87.01%。乔木层的华润楠虽然只有1株高大古树,但其以18.97%的重要值排在所有树种中的第4位,灌木层的华润楠(平均高度20 cm以下的幼苗)以37.06%的重要值排第2位,绒毛润楠为乔木层和灌木层明显的优势树种。群落垂直结构的物种多样性格局表现为：物种丰富度指数为乔木层>灌木层>草本层>藤本层;均匀度指数为藤本层>草本层>乔木层>灌木层;多样性指数D和H''最高的均为草本层,最低的均为灌木层。因此,该群落属于亚热带性质常绿阔叶林,物种组成相对丰富,华润楠古树生长正常,但种群不稳定,应加强保护。     

同期生长在种源地与异地同质园刨花楠叶性状分析

为辨别环境变化与遗传因素对植物叶片主要功能性状的影响,以同期生长在4种源地母树林下及异地同质园的1.5年生刨花楠苗木为研究对象,对其叶片表型及养分性状进行对比分析。结果显示：(1)刨花楠叶面积、叶厚、叶干物质含量等叶片表型性状受遗传与环境因素共同影响;叶片碳(C)含量受遗传因素调控,环境对其影响较小;叶片氮、磷(N、P)含量主要受环境因素影响;(2)不同种源刨花楠比叶面积、叶厚、叶干物质含量、叶形指数等性状变异系数较大(8.85%—37.03%),其中江西遂川种源变异系数相对较大,而湖南茶陵种源则相对较小,各种源都倾向于通过调节比叶面积、叶厚、叶片氮磷含量等性状以适应生境变化;(3)种源地与同质园刨花楠的比叶面积虽均与叶厚呈显著负相关,但同质园刨花楠比叶面积与叶形指数呈显著正相关,与叶片氮含量无明显相关,而种源地刨花楠比叶面积则与叶形指数无明显相关,与叶片氮含量则呈显著负相关;(4)不同种源苗木叶性状指标在种源地与同质园间存在不同的协调与权衡,体现了植物在不同生境下的适应策略。其中湖南茶陵种源在两种生境下都具有更保守的资源获取策略,而江西安福种源对环境变化则更为敏感,资源获取策略更为灵...     

Difference of invasion behavior between two climax species,Castanopsis cuspidata var.sieboldii andMechilus thunbergii,on lava flows on Miyakejima,Japan

The invasion behavior of two climax species,Machilus thunbergii Sieb. et Zucc. andCastanopsis cuspidata (Thunb.) Schottky var.sieboldii (Makino) Nakai, was studied on the 1874 and 1962 lava flows on Miyakejima, Japan. On the 1962 lava, zoochorousM. thunbergii appeared almost only under crowns of pioneeringAlnus sieboldiana Matsum, while bolochorousC. cuspidata var.sieboldii occurred only along the borders of the lava. The three species,A. sieboldiana, M. thunbergii andC. cuspidata var.sieboldii, corresponded, in order, to the temporal sequence of invasion in the boundary forest and the spatial sequence from margin to center on the 1962 lava. Seed or fruit dispersion is important in primary succession in the case of large disturbances.     

樟树新害虫——窃达刺蛾的研究

窃达刺蛾是樟树新害虫,在福建一年发生3代,以幼虫在叶背越冬。翌年3月上旬化蛹,4月上旬成虫出现并产卵,4月中旬幼虫孵出,5月中旬陆续化蛹．6月上旬成虫羽化,6月中旬第二代幼虫开始出现,8月下旬第三代幼虫出现。在幼虫三龄前,喷洒5％辛硫磷,40％氯化乐果乳剂或80%敌敌畏乳剂1000倍液,均可收到良好效果。     

人工林刨花楠木材主要特性的径向变异及其对气象因子的响应

为了给刨花楠材质预测、轮伐期选择及木材合理高效利用提供理论基础,本研究以17年生刨花楠人工林为对象,采用木材性质快速测定仪(SilviScan-3^TM)获得木材性质参数,研究人工林刨花楠解剖特性、木材密度与弹性模量的径向变异规律及其对气象因子的响应,重点分析生长轮宽度、年龄与各材性性质参数之间的相关性.结果表明: 刨花楠不同材性性状的径向变异规律不同,7～11生长轮为其变异曲线的转折点;木材密度和纤维壁腔比与生长轮宽度的相关性不显著,生长速度和生长轮年龄对大部分材性性状具有重要影响;不同气象因子对不同材性性状影响程度不尽相同,相对湿度是影响刨花楠材性的主要生态因子;各材性性状中,微纤丝角和弹性模量对气象因子的响应更敏感.     

竹亚科簕竹属吊罗坭竹繁殖器官的补充描述

《中国植物志》第九卷第一分册及其它的相关文献均无关于竹亚科簕竹属吊罗坭竹花的描述或记录,本文作者采集制作了该竹子繁殖器官标本,并分别用中文和拉丁文对其进行了描述,其主要特征：花枝长70~170 cm;花序为总状花序或简单的圆锥花序;花序轴粗,节明显;小穗含4~5朵小花;小穗无柄;小穗轴节间无毛,呈棒状;颖2,膜质;外稃长或等于内稃;鳞被2;雄蕊6;子房卵形;柱头3,呈毛刷状;颖果未见。花期2~3月。花标本采自厦门市园林植物园。     

氮磷配施对刨花楠幼林细根性状的影响

氮磷是陆地生态系统植物生长的主要限制性元素,细根对植物生长具有重要影响.为了解氮磷配施对刨花楠人工幼林细根性状的影响,以3年生刨花楠人工幼林为对象,于2016年和2017年每年4-9月的每月中旬进行氮磷配施(添加比例分别为8∶1、10∶1、12∶1、15∶1),测定比根长、比表面积、平均直径、根组织密度、总碳、总氮含量...     

大果滇新樟,广西新樟属一新变种

该文报道了我国樟科新樟属的一个新变种——大果滇新樟[Neocinnamomum caudatum(Nees)Merr.var.macrocarpum Wenbin Xu et B.S.Xia],该变种与原变种区别在于果实宽椭圆形,长近3 cm,宽达2cm,叶具明显离基三出脉(三出脉距叶基0.5 cm或更长),产自广西壮族自治区德保县东凌乡。     

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.