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151.
Amino acids have been investigated in seeds and fresh parts of members of the Fagaceae. Seeds from the genus Fagus contain willardiine, 5-hydroxy-6-methylpipecolic acids, N-[N-(3-amino-3-carboxypropyl)-3-amino-3-carboxypropyl]azetidine-2-carboxylic acid and γ-glutamyl peptides, mainly γ-glutamylphenylalanine. These compounds are nearly or totally absent from leaves of F. silvatica and from seedlings and immature seeds of F. silvatica var. purpurea; instead, the seedlings contain large amounts of γ-l-glutamyl-l-isoleucine and γ-l-glutamyl-l-leucine. γ-l-Glutamyl-l-tryptophan and γ-l-glutamyl-γ-l-glutamyl-l-phenylalanine, not previously known from nature, have been isolated from seeds of F. silvatica var. purpurea. The structures have been confirmed by syntheses. 4-Hydroxypipecolic acid (with trans-configuration) has been identified in seeds of F. japonica Maxim. and F. sieboldii Endl. None of the above compounds was found in Quercus or Castanea species whereas argininosuccinic acid was identified in Castanea sativa. 相似文献
152.
SERAPHIM HATZISKAKIS IOANNIS TSIRIPIDIS ARISTOTELIS C. PAPAGEORGIOU 《Botanical journal of the Linnean Society. Linnean Society of London》2011,165(4):422-436
Diversity in leaf morphological traits was assessed in 38 Greek Fagus sylvatica populations, covering the distribution of the species in the country. The relationship between the post‐glacial origin of these populations and leaf morphology was investigated. The results showed a complex and geographically continuous morphological diversity pattern, influenced mainly by traits expressing leaf size, leaf shape and petiole length. Two simultaneous trends appeared to be responsible for the existing diversity pattern. One was geographical, with leaf types resembling F. sylvatica subsp. sylvatica occurring in the western part of the distribution of beech in Greece and types resembling F. sylvatica subsp. orientalis being dominant in the eastern part. A second trend seemed to be connected with the post‐glacial origin of the populations, as described by previous plastid DNA haplotype studies of the same trees. The genetic background and the possible adaptation of beech populations to different environmental conditions have resulted in a complex morphological pattern, especially in areas in which different post‐glacial lineages appear to meet. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 422–436. 相似文献
153.
François Hubert Guido W. Grimm Emmanuelle Jousselin Vincent Berry Alain Franc 《分类学与生物多样性》2013,11(4):405-423
Phylogenetic relationships among 108 oak species (genus Quercus L.) were inferred using DNA sequences of six nuclear genes selected from the existing genomic resources of the genus. Previous phylogenetic reconstructions based on traditional molecular markers are inconclusive at the deeper nodes. Overall, weak phylogenetic signals were obtained for each individual gene analysis, but stronger signals were obtained when gene sequences were concatenated. Our data support the recognition of six major intrageneric groups Cyclobalanopsis, Cerris, Ilex, Quercus, Lobatae and Protobalanus. Our analyses provide resolution at deeper nodes but with moderate support and a more robust infrageneric classification within the two major clades, the ‘Old World Oaks’ (Cyclobalanopsis, Cerris, Ilex) and ‘New World Oaks’ (Quercus, Lobatae, Protobalanus). However, depending on outgroup choice, our analysis yielded two alternative placements of the Cyclobalanopsis clade within the genus Quercus. When Castanea Mill. was chosen as outgroup, our data suggested that the genus Quercus comprised two clades corresponding to two subgenera as traditionally recognized by Camus: subgenus Euquercus Hickel and Camus and subgenus Cyclobalanopsis Øersted (Schneider). However, when Notholithocarpus Manos, Cannon and S. Oh was chosen as an outgroup subgenus Cyclobalanopsis clustered with Cerris and Ilex groups to form the Old World clade. To assess the placement of the root, we complemented our dataset with published data of ITS and CRC sequences. Based on the concatenated eight gene sequences, the most likely root position is at the split between the ‘Old World Oaks’ and the ‘New World Oaks’, which is one of the alternative positions suggested by our six gene analysis. Using a dating approach, we inferred an Eocene age for the primary divergences in Quercus and a root age of about 50–55 Ma, which agrees with palaeobotanical evidence. Finally, irrespective of the outgroup choice, our data boost the topology within the New World clade, where (Protobalanus + Quercus) is a sister clade of Lobatae. Inferred divergence ages within this clade and the Cerris–Ilex clade are generally younger than could be expected from the fossil record, indicating that morphological differentiation pre-dates genetic isolation in this clade. 相似文献
154.
155.
Tree recruitment at the Nothofagus pumilio alpine timberline in Tierra del Fuego, Chile 总被引:3,自引:1,他引:2
Jaime G. Cuevas 《Journal of Ecology》2000,88(5):840-855
156.
Cupule and pistillate inflorescence morphology is described in detail for the first time for a number of species in Nothofagus subgenus Lophozonia. The architecture and temporal appearance of prophylls, flowers, and cupule valves is dichasial; the cupule valves are third
and higher order shoot systems. Comparative studies demonstrate that the dorsal rows of appendages on the cupule valves have
a similar arrangement, and each row exhibits the same temporal pattern of development. This suggests that the cupule valves
in all species have a modular construction and consist of rows of homologous appendages. This study clearly demonstrates the
uniform groundplan of the pistillate inflorescence in this subgenus.
Received March 14, 2002; accepted May 8, 2002 Published online: September 13, 2002 相似文献
157.
158.
ZHOU Zhe-Kun 《植物分类学报:英文版》1999,37(4):369-385
The fossil history of the Fagaceae from China and its systematic and biogeographic
implications are discussed based on revisionary studies of the fossil records. No creditable
macrofossil record of the Fagaceae exists in the Cretaceous deposits and all the Cretaceous microfossil reports remain equivocal and require further study. The Paleocene fossils show the
appearance and diversification of the two groups corresponding to the subfamilies Fagoideae
and Castaneoideae sensu Nixon. By the Eocene, all modern genera had been present. The
oldest fagaceous fossils represent subfamily Fagoideae with affinities to the extant genus
Trigonobalanus. The leaf fossil genus Berryophyllum, with affinities to Quercus subg. Cyclobalanopsis, has been documented by the early Eocene and might have occurred earlier than
other fossils assignable to Quercus. The appearance of evergreen sclerophyllous Ouercus
with entire leaves might have occurred earlier than those with toothed leaves. Deciduous, urticoid-leaved oak fossils (Quercus subg. Quercus sect. Quercus) had not appeared until the
Miocene. Fossil equivalents of Trigonobalanus, Castanopsis and Lithocarpus had occurred
in Europe and North America by the early Tertiary, suggesting that continuous distributions
were achieved via the northern hemisphere land bridges. Three groups of evergreen sclerophyllous oaks of apparent close phylogenetic relationships occurred in the Hengduan mountains, the Mediterranean area and northwestern North America. Their fossil forms have become dominant elements of those vegetation zones since the Miocene. A shared fossil history
indicates a possible biogeographic boundary formed by the ancient Mediterranean. The evidence suggests that the oaks might arrive in North America during two distinct geologic periods: evergreen sclerophyllous entire-leaved oaks appeared by the Early Tertiary, whereas thedeciduous oaks with urticoid leaves appeared in the Late Tertiary. 相似文献
159.
The characters of leaf epidermis (mainly epidermal cells, stomata, trichomes) have been
examined in 48 species of Quercus subgen. Cyclobalanopsis of the Fagaceae. The adaxial leaf epidermis was investigated under light microscope. The epidermal cells of this surface are of two types
in terms of the outline of their anticlinal wall. One type is characterized by having straight wall, and this type has been observed in most of the species studied, while the other is characterized by having
sinuate or sinuolate wall, and this type has been found only in eight species, such as Q. blakei and
Q. hui. There exist two types of trichome-bases on this surface: in one type the bases are singlecelled, and this type has been found in most of the species studied, such as Q. oxyodon and Q.
augustinii; while in the other the bases consist of a group of cells, and this type has been found
only in nine species, such as Q. thorelii and Q. chungii. The abaxial leaf epidermis was investigated under light microscope and scanning electron microscope. The epidermal cells and the
trichome-bases on this surface under LM are in morphology essentially similar to those on the adaxial
surface. The stomata under LM include three types: cyclocytic, subcyclocytic and anomocytic. The
stomatal density is of some diagnostic value to distinguish between closely related species, e.g. the
stomatal density in Q. glauca is higher than that in Q. schottkyana. Under SEM the stomata are
elliptical or roundish. The most noteworthy feature of the adaxial leaf epidermis is the trichomes.
Eight types of trichomes have been observed under SEM: simple-uniseriate, solitary, papillae, stellate, fused-stellate, stipitate-fasciculate, multiradiate and jellyfish-like. The first type, i.e. the
simple-uniseriate trichome, is glandular, other six types, i.e. the solitary, papillae, stellate,
fused-stellate, stipitate-fasciculate and multiradiate trichomes, are non-glandular, and the last one,
i.e. the jellyfish-like trichome, may represent an intermediate type in structure between the glandular and the non-glandular trichomes. Papillae are very common in subgen. Cyclobalanopsis although
in the Fagaceae they were previously reported only in a few species of Lithocarpus. The jellyfish-like
trichome, observed only in Q. sichouensis, is reported in the Fagaceae for the first time. The evolutionary trends of trichomes are discussed. The trichomes seem to evolve toward the direction of increasing complexity in structure. Papillae are considered as the pedomorphism of trichomes. From
papillae the solitary trichomes and then the stellate ones have evolved. The complicated trichome
types with more arms may be produced from relatively simple ones with fewer arms by means of varions fusion: several stellate trichomes are fused to form the fused-stellate ones by basal fusion, and
by the same way the fused-stellate ones to form the stipitate-fasciculate ones; the multiradiate
trichomes are formed by the stellate ones, in which the arms emerge in a variety of seemingly random
directions from a typically rounded common base. Based on the above results, it is considered that
the trichome features are of important significance for a better understanding of the infrageneric division of Quercus and the phylogenetic relationships between this genus and the other genera in the
Fagaceae. The very common presence of papillae in Quercus subgen. Cyclobalanopsis and in a few
species of Lithocarpus may indicate that subgen. Cyclobalanopsis is a quite natural group on the one
hand, and may have close relationship with Lithocarpus on the other hand. The thin-walled, jellyfish-like trichomes found in Q. sichouensis are in structure similar to the “glandular” peltate
trichomes in Trigonobalanus, a genus generally regarded as the most primitive in subfam. Quercoideae, indicating that the affinity between subgen. Cyclobalanopsis and Trigonobalanus may becloser than that between subgen. Quercus and Trigonobalanus. 相似文献
160.
壳斗科植物摘录(Ⅱ) 总被引:2,自引:1,他引:1
本文报道柯属Lithocarpus Bl。的新分类群,即17新种,7新变种,新名3,新组合5,对少好的种作了订正。属的中名取名为柯,并作简要的讨论。又文内提到的绝大多数的新种,早在1982年出版的《中国高等植物图鉴》补编Ⅰ里用分种检索的形式作了初报,但全部都是裸名。此外,尚有个别种更改其等级或归并。 本文引用的标本,除属华南植物研究所SCBI外均注明标本的保存单位(标术室缩写代号见植物分类学报20(2):252—256,1982)。 相似文献