Michelia sonlaensis Q.N. Vu,sp. nov. (Magnoliaceae) from northern Vietnam

Michelia sonlaensis Q.N. Vu, a new species of Michelia from Son La province, northern Vietnam is described. The new species is assigned to the genus Michelia (separated from Magnolia), subfamily Magnolioideae based on general morphology. It is closely similar to M. xianianhei and M. mannii, but differs mainly in having a leaf‐lamina that is elliptic, thinly leathery, larger, with lower surface yellowish white villous (easily visible by eyes and feeling by hand), brachyblasts and outside bracts yellowish‐white sericeous, flowers light green to cream white in colour, and nine tepals with the outside of all tepals silky hairy at base.     

干旱胁迫下广东石漠化地区造林树种光合和耗水特性

石漠化地区土层稀薄、干旱贫瘠、植被破坏、生态恶化等问题较为突出,人工恢复森林植被是一项快速有效的生态恢复途径。采用盆栽苗木称重法和Li-6400光合系统测定方法分别测定3个常见石漠化造林树种浙江润楠(Machilus leptophylla),枫香(Liquidambar formosana)和亮叶含笑(Michelia fulgens Dandy)苗木在不同土壤水分条件下耗水特性和光合特性,为进一步筛选和评价石漠化地区造林树种抗旱特性提供理论依据。研究结果表明:(1)整个干旱胁迫期间,3种幼苗叶片的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)和胞间CO_2浓度(Ci)持续下降。重度干旱时,浙江润楠光合和水分利用效率分别是枫香的2.5倍、89.6倍和亮叶含笑的1.9倍、26.3倍。(2)干旱胁迫中期和后期,枫香和亮叶含笑净光合速率(Pn)和气孔导度(Gs)下降而胞间CO2浓度(Ci)升高,说明Pn下降的主要原因已经由气孔因素转变为非气孔因素的限制。(3)3个石漠化树种在不同干旱胁迫下日耗水总量和日平均耗水速率均存在显著性差异(P0.05),白天耗水量占总耗水量74%—92%之间。浙江润楠在重度干旱时期还对水分要求还比较大,维持一个相对较高的耗水速率,是枫香和亮叶含笑的3.7倍和2.2倍。(4)不同干旱胁迫下,3个石漠化树种耗水速率日变化均表现出单峰曲线,不同干旱胁迫下峰值点会发生变化。(5)综合来看,浙江润楠和枫香是相对高光合和高水分利用效率树种。隶属函数结果表明,在正常、轻度和重度干旱下抗旱能力均为枫香浙江润楠亮叶含笑,重度干旱下为浙江润楠枫香亮叶含笑。     

遮阴对三种木兰科幼苗生长和光合特性的影响

为探讨观光木、山白兰和灰木莲三种木兰科植物对不同光环境的光合适应机制,该文以其幼苗为材料,设置透光率分别为100%NS、72.3%NS、48.6%NS、24.9%NS的四种光照处理,测定其光合特性参数、生物量分配比例、叶绿素含量等,研究不同遮阴处理对其生长和光合作用的影响。结果表明:(1)过强或过弱的光照环境限制了幼苗株高及地径的生长,与全光照相比,72.3%NS有利于幼苗的形态生长。(2)随着遮阴程度的增加,观光木、山白兰和灰木莲幼苗的最大光合速率、光补偿点、光饱和点、暗呼吸速率、蒸腾速率逐渐降低,叶绿素含量增加,水分利用效率先升后降。(3)随着光强的减弱,观光木和山白兰地上部分的生物量积累增加,灰木莲的根生物量积累增加。(4)观光木的比叶面积随着遮阴程度的增加而先增后减;灰木莲的比叶面积显著减小;山白兰的比叶面积差异不显著;观光木、山白兰和灰木莲对低光环境响应和适应的差异主要表现在生物量分配比例及叶的形态特征上。综上结果认为,72.3%NS最有利于幼苗的生长,观光木、山白兰和灰木莲在遮阴条件下可以通过降低P_max、LSP、LCP、R_d、T...     

甘肃省被子植物分布新记录

报道了甘肃省分布的玄参科(Scrophulariaceae)水茫草属(Limosella Linn.)1个新记录属,以及玄参科(Scrophulariaceae)、木兰科(Magnoliaceae)、蓼科(Polygonaceae)、胡颓子科(Elaeagnaceae)、百合科(Liliaceae)5个新记录种——水茫草(Limosella aquatica Linn.)、峨眉含笑(Michelia wilsonii Finet et Gagnep.)、叉分蓼(Polygonum divaricatum L.)、棱果沙棘(Hippophae goniocarpa Y.S.Lian et al.ex SwensonBartish)、青海黄精(Polygontum qinghaiense Z.L.Wu et Y.C.Yang)。其中,峨眉含笑是国家二级重点保护野生植物。     

台山含笑，广东木兰科一新种

报道了木兰科（Magnoliaceae）含笑属（Michelia L.）一新种：台山含笑（M. taishanensis Y. H. Tong,X. E. Ye,X. H. Ye & Yu Q. Chen）。该新种目前仅分布于我国广东台山市的北峰山,与广东含笑（M. guangdongensis Y. H. Yan,Q. W. Zeng & F. W. Xing）近缘,但其叶柄更纤细,叶背老时变无毛,雄蕊较多且较长,花丝白色,药隔短小而与后者区别。     

Comparative floral anatomy and ontogeny in Magnoliaceae

Floral anatomy and ontogeny are described in six species of Magnoliaceae, representing the two subfamilies Liriodendroideae (Liriodendron chinese and L. tulipifera) and Magnolioideae, including species with terminal flowers (Magnolia championi, M. delavayi, M. grandiflora, M. paenetalauma) and axillary flowers (Michelia crassipes). The sequence of initiation of floral organs is from proximal to distal. The three distinct outermost organs are initiated in sequence, but ultimately form a single whorl; thus their ontogeny is consistent with a tepal interpretation. Tepals are initiated in whorls, and the stamens and carpels are spirally arranged, though the androecium shows some intermediacy between a spiral and whorled arrangement. Carpels are entirely free from each other both at primordial stages and maturity. Ventral closure of the style ranges from open in Magnolia species examined to partially closed in Michelia crassipes and completely closed in Liriodendron, resulting in a reduced stigma surface. Thick-walled cells and tannins are present in all species except Michelia crassipes. Oil cells are normally present. Floral structure is relatively homogeneous in this family, although Liriodendron differs from other Magnoliaceae in that the carpels are entirely closed at maturity, resulting in a relatively small stigma, in contrast to the elongate stigma of most species of Magnolia. The flower of Magnolia does not terminate in an organ or organ whorl but achieves determinacy by gradual diminution.     

不同砧木阔瓣含笑嫁接苗生长生理及亲和性评价

以白玉兰、紫玉兰、乐昌含笑、深山含笑作砧木的阔瓣含笑嫁接苗为材料,通过对嫁接苗生长特性的观测和生理生化指标的动态测定,运用主成分分析和隶属函数法计算亲和性综合指数,评价阔瓣含笑与4种砧木的苗期亲和性。结果表明:以深山含笑和紫玉兰作砧木的嫁接成活率较高(分别为88.33%、83.33%),白玉兰次之(为75%),乐昌含笑较低(为63.3%);砧木对嫁接苗的苗高有较大影响,以深山含笑和紫玉兰的苗高最高,白玉兰次之,乐昌含笑最矮;砧木对嫁接苗叶片数的影响表现为初期存在一定差异,生长后期差异逐渐缩小。在嫁接苗生长过程中,4种砧木嫁接苗的叶绿素含量均呈双峰型变化,类胡萝卜素含量、可溶性蛋白含量、POD活性表现出先上升后下降的趋势,可溶性糖含量总体表现为先下降后上升的趋势。在4种砧木的嫁接苗中,深山含笑、紫玉兰和白玉兰的各项生理指标都相近,而乐昌含笑整个生长期都低于其它3种嫁接苗。从亲和性综合指数来看,深山含笑的亲和性指数最高(为0.518),乐昌含笑的最低(为0.470)。综合分析,认为4种砧木与阔瓣含笑都具有一定的亲和性,其中以深山含笑最好,乐昌含笑最差。     

Some fossil woods from the palaeogene of Northern Kyushu

From the Tsuyazaki Formation (Oligocene) of Tsuyazaki-machi, Fukuoka Prefecture, the following four new species of dicotyledons are described based on woody fossils:Castanea protantiqua M. Suzuki (Fagaceae),Michelia oleifera M. Suzuki (Magnoliaceae),Reevesia oligocenica M. Suzuki (Sterculiaceae) andPlatanus tsuyazakinensis M. Suzuki (Platanaceae).     

ONTOGENY OF THE FLORAL APEX OF MICHELIA FUSCATA

Tucker , Shirley C. (u . Minnesota, Minneapolis.) Ontogeny of the floral apex of Michelia fuscata. Amer. Jour. Bot. 47(4): 266—277. Illus. 1960.–The floral apex of Michelia fuscata, although determinate, has a prolonged period of activity. It undergoes an increase in average height and diameter through the time of initiation of stamens, followed by a decrease in average size during initiation of successive carpels. The floral apex also shows periodic or plastochronic fluctuation in size and configuration between initiation of tiers of appendages at nearly the same level and time. Plastochrons of different duration alternate in an orderly sequence in the floral meristem.     

Über die Karpelle verschiedener Magnoliales. IV.Magnolia undMichelia (Magnoliaceae)

Zusammenfassung Die Karpelle vonMichelia kingii besitzen einen deutlich erkennbaren Schlauchteil, der nur basal mit der Blütenachse verwachsen ist. Diese Tatsache erlaubt die Folgerung, daß auch die Karpelle vonMagnolia peltat gebaut sind, welche Bauweise sich hier ja bereits durch das Vorkommen eines Ventralmedianus andeutet; jedoch ist ihr Schlauchteil zur Gänze mit der Blütenachse verwachsen und damit maskiert. Auch für die Karpelle der restlichen Magnoliaceen-Gattungen dürfte dies mit großer Wahrscheinlichkeit zutreffen, vor allem für jene vonLiriodendron undTalauma, welche ebenfalls einen Ventralmedianus ausgebildet haben.     

浙江含笑属一新种——尾叶含笑

该文报道了采自中国浙江庆元县百山祖国家级自然保护区木兰科含笑属一新种——尾叶含笑(Michelia caudata M.X.Wu,X.H.Wu & G.Y.Li),该种与野含笑(M.skinneriana)和紫花含笑(M.crassipes)相近,但与野含笑的区别在于叶片倒卵形至倒卵状椭圆形,叶背面密被黄褐色茸毛,长5～7.5 cm,宽2.5～3.2 cm,先端尾尖,侧脉每边约6对,花被片椭圆形;与紫花含笑的区别在于花被片淡黄色,雌蕊群柄长3～4 mm。根据国际自然及自然资源保护联盟(IUCN)红色名录分类标准,尾叶含笑濒危等级为极度濒危。     

ONTOGENY AND PHYLLOTAXIS OF THE TERMINAL VEGETATIVE SHOOTS OF MICHELIA FUSCATA

Tucker Shirley C. (Northwestern U., Evanston, Ill.) Ontogeny and phyllotaxis of the terminal vegetative shoots of Michelia fuscata. Amer. Jour. Bot. 49(7): 722–737. Illus. 1962.—Two patterns of symmetry occur in Michelia fuscata In the lead shoots, leaves arise in a 2/5 spiral arrangement which may be either clockwise or counterclockwise. Other shoots are dorsiventrally organized; these shoots produce leaves in a modified ½ phyllotaxis in which the angle between the 2 files of leaves lies between 100° and 150°, according to the particular branch. Both types of shoot have a zonate apical meristem with a biseriate tunica a central initial zone, and a peripheral zone. The apical configuration of cells does not change appreciably during the plastochron. The flat to low-convex outline of the shoot apex is maintained by initiation of the leaves close to the summit of the apex; the diameter of the meristem diminishes greatly after such an initiation. Leaf inception in the subsurface tunica layer is followed by precocious activity of the marginal meristems which extend the stipular flanges completely around the base of the apical meristem. The stipular margins then fuse laterally and form a hood over the apex. A subapical initial meanwhile is active in the leaf blade, where it persists up to the time the leaf is 2 mm high. The most recent primordium is 300 μ high before another leaf is initiated. The vascular system of the stem is a cylindrical network of leaf traces, with 6–12 traces per leaf. The procambium develops acropetally from preexisting vascular strands in the stem below. Elements of the diverse sclereid system differ in shape in different tissues, according to the availability of intercellular space. Goebel's term “Pendelsymmetrie” is discussed with reference to apical activity in Michelia.     

含笑花药发育的超微结构研究

对含笑花药发育中的超微结构变化进行观察,结果显示:(1)花粉发育中有三次液泡变化过程——第一次是小孢子母细胞在形成时内部出现了液泡,这可能与胼胝质壁的形成有关;第二次是在小孢子母细胞减数分裂之前,细胞内壁纤维素降解区域形成液泡,它的功能可能是消化原有的纤维素细胞壁;第三次是在小孢子液泡化时期,形成的大液泡将细胞核挤到边缘,产生极性。(2)含笑花粉在小孢子早期形成花粉外壁外层,花粉外壁内层在小孢子晚期形成,而花粉内壁是在二胞花粉早期形成;花粉成熟时,表面上沉积了绒毡层细胞的降解物而形成了花粉覆盖物。研究认为,含笑花粉原外壁的形成可能与母细胞胼胝质壁有关,而由绒毡层细胞提供的孢粉素物质按一定结构建成了花粉覆盖物。     

湖北4种木本植物新记录及资源现状

2017～2019年,我们在对湖北五峰后河国家级自然保护区进行本底资源调查过程中发现了若干新记录。本文对其中4种木本植物新记录进行报道,分别为乐东拟单性木兰[Parakmeria lotungensis(ChunC.H. Tsoong) Y.W. Law]、乐昌含笑(Michelia chapensis Dandy)、峨眉鹅耳枥(Carpinus omeiensis H.H. HuD. Fang)和尾叶紫薇(Lagerstroemia caudata ChunF.C. How ex S.K. LeeL.F. Lau)。同时,我们也对这4种木本植物的种群现状、濒危状况和资源利用进行了调查,为进一步保护工作的开展提供了基础。     

华南地区裸子植物与被子植物季节性水分利用的比较研究

为了解气候温暖区的裸子植物与被子植物的水分利用异同,利用Granier热消散探针法(TDP)连续监测华南地区裸子植物池杉(Taxodium ascendens)、落羽杉(T. distichum)和被子植物枫香树(Liquidambar formosana)、乐昌含笑(Michelia chapensis)的树干液流,对干湿季裸子植物与被子植物水分利用的差异及其与环境因子的关系进行了研究。结果表明,光合有效辐射和水汽压亏缺与树木的整树蒸腾速率和整树日均耗水量呈显著正相关;干季池杉和落羽杉的整树蒸腾速率与整树水力导度均显著低于枫香树和乐昌含笑;而在湿季则正好相反。这为华南地区园林造景和养护管理提供了科学依据。     

THE TERMINAL IDIOBLASTS IN MAGNOLIACEOUS LEAVES

The idioblasts terminating the foliar veinlets were studied in 152 species of the following magnoliaccous genera: Alcimandra, Aromadendron, Elmerrillia, Kmeria, Liriodendron, Magnolia, Manglietia, Michelia, Paramichelia, and Talauma. In all genera, except Liriodendron, some of the veinlets in mature leaves terminate in enlarged, nonliving cells called tracheoidal elements. Only one wall-facet (rarely 2) in such elements is differentially thickened; this wall lies adjacent to a conventional tracheary element. Ultimate cells of other veinlets in the Magnoliaceae differentiate as thick-walled sclereids, conventional tracheids, clavate tracheids, reticulate-walled dilated tracheids, or secretory cells. The terminal elements differentiate relatively late during leaf enlargement. In the Magnoliaceae, foliar structure is frequently characteristic at the generic level, and in some cases at the species level.     

Phylogenetic relationships in Magnoliaceae subfam. Magnolioideae: a morphological cladistic analysis

Relationships within Magnolioideae have been the subject of persistent debate; the main point at issue mostly being the disposition of tribes, genera and sections. A morphological cladistic analysis of the subfamily using Liriodendron as the out-group showed that Magnolioideae consisted of a large basal polytomy, but with five resolved and variously supported clades. Manglietia constituted a clade with sect. Rytidospermum of Magnolia subg. Magnolia. Kmeria and Woonyoungia formed a pair. Pachylarnax, Parakmeria and Manglietiastrum were grouped together, and sect. Splendentes and Dugandiodendron also formed a pair. The largest and best supported clade consisted of Magnolia subg. Magnolia sects. Oyama and Maingola, Magnolia subg. Yulania, Michelia, Aromadendron, Alcimandra, Elmerrillia, Paramichelia and Tsoongiodendron, with sect. Oyama of Magnolia subg. Magnolia is sister to the remainder. Although Magnolia sect. Maingola, Aromadendron, Alcimandra and Elmerrillia constituted a poorly resolved subclade, Aromadendron formed a monophyletic clade with Alcimandra. Within the Michelia/Magnolia subgen. Yulania subclade, Paramichelia was sister to Tsoongiodendron. These results are supported by similar placement of taxa within various molecular analyses of the family, but the low level of resolution indicates that more morphological data are needed to improve phylogenetic signal. Our results support the molecular analyses in suggesting that Magnolia is best considered to be a large and diverse genus, but that the relationships between the taxa within it require more detailed clarification, with more extensive sampling and a combined molecular and morphological approach being needed.     

越南植物Michelia tonkinensis(木兰科)的模式考订

Michelia tonkinensis A. Chev.这个名称在发表时未指定模式,曾被处理为M. balansae (Aug. DC.) Dandy的异名。在查阅了其原白和原始材料后,确认采自越南北部Tuyen Quang省的标本——Fleury 37.667 (P)是该种唯一的原始材料,应该作为模式看待,同时确认Michelia tonkinensis是一独立的种,不应该处理为M. balansae的异名。此外,还提供了M. tonkinensis的异名、俗名、描述、分布及查阅的标本等综合信息。     

PHYLLOTAXIS AND VASCULAR ORGANIZATION OF THE CARPELS IN MICHELIA FUSCATA

Tucker , Shirley C. (U. Minnesota, Minneapolis.) Phyllotaxis and vascular organization of the carpels in Michelia fuscata. Amer. Jour. Bot. 48(1): 60–71. Illus. 1961.—Phyllotaxis pattern and vascular organization are closely related in the floral receptacle of Michelia fuscata (Magnoliaceae). The carpels arise in a spiral or helix. They are initiated alternately along each of 7, 8 or 10 helical parastichies according to a complex repetitive sequence. The pattern of the dorsal carpellary trace fusions is orderly for each of the 10 flowers investigated. The dorsal carpellary traces in each parastichy diverge from the same vascular sympodium. Among flowers one finds differing numbers of parastichies, differing angles of divergence, and varying sequences of parastichies which reflect the order of carpel initiation. The angle of divergence, although consistent for any 1 parastichy in a flower, can vary greatly between parastichies. The nature and importance of the organizers which determine appendage position at the apical meristem are considered. Changes in apical size, configuration, and activity are shown to be related to phyllotaxis.     

Phylogenetic relationships of the Magnoliaceae inferred from cpDNA matK sequences

The coding region of the matK gene was sequenced to infer the phylogeny of the family Magnoliaceae. Phylogenetic analyses of 21 matK sequences representing ten genera of Magnoliaceae and three outgroups suggest relationships among both subfamilies and genera. Monophyly of the subfamily Liriodendroideae (the genus Liriodendron) and the subfamily Magnolioideae is strongly supported, respectively. Within the subfamily Magnolioideae, three clades are formed: (1) the genus Magnlietia, (2) the subgenus Magnolia, and (3) the subgenus Yulania, with the genera Michelia, Paramichelia, Tsoongiodendron, Alcimandra, Kmeria, Parakmeria and Manglietiastrum. However, the genus Magnolia is shown to be a polyphyletic group, and the genus Michelia a paraphyletic group. Relatively low sequence divergences are detected among genera of the the subfamily Magnolioideae, ranging from 0.14% to 1.70%, especially in the tribe Micheliinae (0.14–0.98%). Molecular evidence from matK sequence data suggests that the phylogenetic positions and the delimitation of the eight genera Magnolia, Michelia, Tsoongiodendron, Paramichelia, Alcimandra, Kmeria, Parakmeria and Manglietiastrum need to be reconsidered. Received: 2 January 2000 / Accepted: 12 February 2000