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1.
The tracheid bar, a strip composed of vertically oriented large tracheid-like cells (tracheoids), occurs only in the hilum of seeds of papilionoid legumes. An anatomical survey of the bar was made from seeds representing 232 species of 97 genera from 29 of the 31 tribes recognized by Polhill. Seeds were sectioned freehand, coated, then viewed by SEM. The tracheid bar is quite uniform in its general features throughout the subfamily, although differences in size and shape of both the bar and the tracheoids were found. Eight species from tribes considered to be among the primitive elements of the subfamily exhibited three variant forms: horizontal tracheary elements instead of the usual bar (2 species), tracheid bar with subtending but separate vascular bundle (1 species), and the tracheid bar with fused horizontal tracheary elements (5 species). Bordered pits of individual cells in the tracheid bar virtually always lacked a membrane and had smooth, warty, or variously elaborate vestures on the border. This appears to be the first report of vestured pits other than in secondary xylem. With some exceptions, bordered pits tended to be vestured in primitive tribes, warty in intermediate tribes, and smooth or only slightly warty in the most advanced tribes.  相似文献   

2.
The epidermal characters of mature leaves of 29 genera, 50 species and 3 varieties (totally 56 samples) representing all the 5 tribes in the family Menispermaceae were examined under the light microscope. The main conclusions are as follows: (1) The shape of the epidermal cells is polygonal or irregular, and the anticlinal walls are straight or waved in the family. In some genera a special arrangement of epidermal cells is named as “rosette-cell arrangement" for the first time. The lower epidermal cells were found to have a papilla in Stephania, Diploclisia and Legnephora . (2) In some genera, the anticlinal walls are oblique, rather than perpendicular, to the surface. (3) The stomatal apparatuses, generally restricted to the lower surface of the leaves, were assigned to anomocytic, staurocytic, cyclocytic, anisocytic and actinocytic types, and their distribution on the epidermis may be of diffuse pattern or island congregating pattern. (4) The cells of both upper and lower epidermis in the tribe Pachygoneae and Fibraureae are generally polygonal with straight or arched anticlinal walls, and the stomatal apparatuses are usually staurocytic and actinocytic. The cyclocytic stomatal apparatus was found only in two genera of the tribe Pachygoneae. By contrast, the epidermal cells of the tribes Anomospermeae, Tinosporeae and Menispermeae are generally irregular with waved anticlinal walls, and the stomatal apparatuses are predominantly anomocytic. These correlated characters are of much significance in delimiting tribes within the Menispermaceae, and also provide evidence for studies on systematic relationships of several genera.  相似文献   

3.
Subsidiary cell formation in leaves of the Oncidieae begins with the production of a trapezoid cell on each side of the guard cell mother cell. The trapezoid cells are formed by oblique divisions in the tiles of cells next to the tile of cells containing the guard cell mother cell. The trapezoid cell usually divides unequally to form a subsidiary cell and a derivative cell. The subsidiary cell is smaller and next to the guard cell mother cell. The derivative cell enlarges and is often indistinguishable from the other epidermal cells. Rarely, polar subsidiary cells are also formed. In very rare cases the smaller of the division products of the trapezoid cell divides to form two subsidiary cells next to each guard cell. Subsidiary cells have been found in all tribes of the epidendroid and vandoid groups, all neottoid tribes examined except the Orchideae, and the subfamily Cypripedioideae. The absence of subsidiary cells in primitive genera of the epidendroid tribes and the presence of subsidiary cells in the most advanced genera of the epidendroid and vandoid groups supports the hypothesis that the presence of subsidiary cells is an advanced condition in the Orchidaceae.  相似文献   

4.
We present an updated worldwide phylogenetic classification of Poaceae with 11 783 species in 12 subfamilies, 7 supertribes, 54 tribes, 5 super subtribes, 109 subtribes, and 789 accepted genera. The subfamilies (in descending order based on the number of species) are Pooideae with 4126 species in 219 genera, 15 tribes, and 34 subtribes; Panicoideae with 3325 species in 242 genera, 14 tribes, and 24 subtribes; Bambusoideae with 1698 species in 136 genera, 3 tribes, and 19 subtribes; Chloridoideae with 1603 species in 121 genera, 5 tribes, and 30 subtribes; Aristidoideae with 367 species in three generaand one tribe; Danthonioideae with 292 species in 19 generaand 1 tribe; Micrairoideae with 192 species in nine generaand three tribes; Oryzoideae with 117 species in 19 genera, 4 tribes, and 2 subtribes; Arundinoideae with 36 species in 14 genera and 3 tribes; Pharoideae with 12 species in three generaand one tribe; Puelioideae with 11 species in two generaand two tribes; and the Anomochlooideae with four species in two generaand two tribes. Two new tribes and 22 new or resurrected subtribes are recognized. Forty-five new (28) and resurrected (17) genera are accepted, and 24 previously accepted genera are placed in synonymy. We also provide an updated list of all accepted genera including common synonyms, genus authors, number of species in each accepted genus, and subfamily affiliation. We propose Locajonoa, a new name and rank with a new combination, L. coerulescens. The following seven new combinations are made in Lorenzochloa: L. bomanii, L. henrardiana, L. mucronata, L. obtusa, L. orurensis, L. rigidiseta, and L. venusta.  相似文献   

5.
We analyzed 1041 individuals belonging to 17 Amerindian tribes of Colombia, Chimila, Bari and Tunebo (Chibcha linguistic family), Embera, Waunana (Choco linguistic family), Puinave and Nukak (Maku-Puinave linguistic families), Cubeo, Guanano, Tucano, Desano and Piratapuyo (Tukano linguistic family), Guahibo and Guayabero (Guayabero Linguistic Family), Curripaco and Piapoco (Arawak linguistic family) and Yucpa (Karib linguistic family). for MHC class II haplotypes (HLA-DRB1, DQA1, DQB1). Approximately 90% of the MHC class II haplotypes found among these tribes are haplotypes frequently encountered in other Amerindian tribes. Nonetheless, striking differences were observed among Chibcha and non-Chibcha speaking tribes. The DRB1*04:04, DRB1*04:11, DRB1*09:01 carrying haplotypes were frequently found among non-Chibcha speaking tribes, while the DRB1*04:07 haplotype showed significant frequencies among Chibcha speaking tribes, and only marginal frequencies among non-Chibcha speaking tribes. Our results suggest that the differences in MHC class II haplotype frequency found among Chibcha and non-Chibcha speaking tribes could be due to genetic differentiation in Mesoamerica of the ancestral Amerindian population into Chibcha and non-Chibcha speaking populations before they entered into South America.  相似文献   

6.
The early phylogeny of the 137 species in the Bovidae family is difficult to resolve; knowledge of the evolution and relationships of the tribes would facilitate comparative mapping, understanding chromosomal evolution patterns and perhaps assist breeding and domestication strategies. We found that the study of the presence and organization of two repetitive DNA satellite sequences (the clone pOaKB9 from sheep, a member of the 1.714 satellite I family and the pBtKB5, a 1.715 satellite I clone from cattle) on the X and autosomal chromosomes by in situ hybridization to chromosomes from 15 species of seven tribes, was informative. The results support a consistent phylogeny, suggesting that the primitive form of the X chromosome is acrocentric, and has satellite I sequences at its centromere. Because of the distribution of the ancient satellite I sequence, the X chromosome from the extant Tragelaphini (e.g. oryx), rather than Caprini (sheep), line is most primitive. The Bovini (cow) and Tragelaphini tribes lack the 1.714 satellite present in the other tribes, and this satellite is evolutionarily younger than the 1.715 sequence, with absence of the 1.714 sequence being a marker for the Bovini and Tragelaphini tribes (the Bovinae subfamily). In the other tribes, three (Reduncini, Hippotragini and Aepycerotini) have both 1.714 and 1.715 satellite sequences present on both autosomes and the X chromosome. We suggest a parallel event in two lineages, leading to X chromosomes with the loss of 1.715 satellite from the Bovini, and the loss of both 1.714 and 1.715 satellites in a monophyletic Caprini and Alcelaphini lineage. The presence and X chromosome distribution of these satellite sequences allow the seven tribes to be distributed to four groups, which are consistent with current diversity estimates, and support one model to resolve points of separation of the tribes.  相似文献   

7.
Four tribes of Arnhem Land were surveyed for dermatoglyphics; based on pattern intensity indices, total ridge-counts, and a distance statistic combining the two, it was shown that the tribes can be arranged into western (Tiwi, Gunwinggu) and eastern (“Murngin” and Andilyaugwa) groups. This substantiates observations made on Arnhem Land by linguists and social anthropologists. From a survey of allele frequency traits of blood factors and P.T.C. tasting, distance statistics were computed between the four tribes. These confirmed the relative isolation of the extreme Arnhem Land tribes. Distance statistics were also computed between the four tribes and two Central Australian tribes, the Aranda and Wailbri. The Aranda and “Murngin” were relatively close together agreeing with theories that the Aranda are derived from a not too remote southwards migration from north Arnhem Land, as supported by linguistic data. Correlations between the biological, geographical and linguistic distances were positive, and generally agreed with the expectation that socio-cultural and linguistic barriers are important in regulating gene flow between populations. This study emphasizes the need to consider biological distances in association with ecological and socio-cultural factors.  相似文献   

8.
Using gene frequency data for 14 genetic loci, genetic distances between 13 tribes of Mexican Indians belonging to 12 language groups were determined and a dendrogram was constructed. The genetic distance between tribes is correlated more with geographic proximity than with language affinity. The gene diversity (heterozygosity) of the total population was decomposed into the three components, i.e., the gene diversity between three main linguistic groups, the gene diversity between tribes within the main linguistic groups and the gene diversity within tribes. About 95% of the total gene diversity exists within tribes, the intergroup and intertribe components being only about 5%.  相似文献   

9.
A total of 292 randomly selected subjects belonging to two indigenous Arab tribes (Harbi and Ghamid) and two immigrant tribes (Mograbi and Mowallad), residents in Western Saudi Arabia, have been tested for genetic variants of six blood groups, four serum proteins, and five red cell enzyme systems. The distribution of the polymorphic systems was different between indigenous and immigrant tribes, and the present Arab population shows a considerable degree of admixture from the surrounding countries, in particular Africa.  相似文献   

10.
Analysis of nine characteristics on 1,205 males and 932 females from 12 tribes or groups of tribes indicated a poor relationship between morphology and language, as well as moderate agreement with the variability expected considering geography only. Two samples in the Xingu area studied during an interval of half a century (1897-1947) showed remarkable similarity. The conformity of the Caingang morphology with those of other tribes and the distinctiveness of the Xavante and Tenetehara has been amply confirmed.  相似文献   

11.
Lipid transfer proteins (LTP) and puroindolines are abundant lipid binding proteins of plant seeds. While LTP are ubiquitous plant proteins, puroindolines are only found in the seeds of plants from the Triticae and Avenae tribes. These proteins display a similar overall folding pattern but different lipid binding properties. The unique and diverse biological and technological functions of LTPs and puroindolines are closely related to their structural and lipid binding properties. These proteins are attractive to improve the agronomic performances and food quality of crops. Heterologous expression and genetic engineering should allow industrial production and enlarge applications of these lipid binding proteins.  相似文献   

12.
Acalyphoideae, the largest subfamily of Euphorbiaceae, are investigated with respect to ovule and seed structure on the basis of 172 species of 80 genera in all 20 tribes of Acalyphoideae sensu Webster. All species of Acalyphoideae examined have bitegmic ovules with a non-vascularized inner integument. However, noticeable differences exist among and sometimes within the genera in the thickness of the inner and outer integument, the presence or absence of vascular bundles in the outer integument, whether ovules are pachychalazal or not, the presence or absence of an aril, seed coat structure (in terms of the best-developed mechanical cell-layer), and the shape of cells constituting the exotegmen. For the latter two characters, two different types of seed coat (i.e., "exotegmic" and "exotestal") and three different types of exotegmic cell (i.e., palisadal, tracheoidal and ribbon-like) were distinguished. Comparisons showed that three tribes Clutieae, Chaetocarpeae and Pereae are distinct from the other Acalyphoideae as well as from the other Euphorbiaceae in having an exotestal seed coat with a tracheoidal exotegmen. The tribe Dicoelieae is also distinct from the other Acalyphoideae in having an exotegmic seed that is composed of ribbon-like cells of exotegmen (i.e., cells both longitudinally and radially elongated, sclerotic and pitted). The tribe Galearieae, which should be treated as a distinct family Pandaceae, is also distinct from the other Acalyphoideae in having an exotegmic seed with a tracheoidal exotegmen (i.e., cells longitudinally elongated, sclerotic and pitted). The remaining genera of Acalyphoideae always have an exotegmic seed with a palisadal exotegmen (i.e., cells radially elongated, sclerotic and pitted). The shared palisadal exotegmen supports the close affinity of Acalyphoideae (excluding five tribes) with Crotonoideae and Euphorbioideae. Within the remaining genera of Acalyphoideae, a significant diversity is found in ovule and seed morphology with respect to the thickness of the inner and outer integument, the size of chalaza, vascularization of an outer integument and an aril.  相似文献   

13.
Phylogenetic relationships were inferred using nucleotide sequence variation of the nuclear-encoded chalcone synthase gene (Chs) and the chloroplast gene matK for members of five tribes from the family Brassicaceae to analyze tribal and subtribal structures. Phylogenetic trees from individual data sets are mostly in congruence with the results from a combined matK-Chs analysis with a total of 2721 base pairs, but with greater resolution and higher statistical support for deeper branching patterns. The analysis indicates that tribes Lepidieae, Arabideae, and Sisymbrieae are not monophyletic. Among taxa under study four different lineages each were detected in tribes Arabideae and Lepidieae, interspersed with taxa from tribes Sisymbrieae, Hesperideae, and Brassiceae. It is concluded that tribe Brassiceae might be the only monophyletic group of the traditional tribes. From our data we estimated several divergence times for different lineages among cruciferous plants: 5.8 mya (million years ago) for the Arabidopsis-Cardaminopsis split, 20 mya for the Brassica-Arabidopsis split, and ~40 mya for the age of the deepest split between the most basal crucifer Aethionema and remaining cruciferous taxa.  相似文献   

14.
Thirty-two genera of the Monimiaceae are assigned to six subfamilies and eight tribes. Two further genera are insufficiently known to be placed. One subfamily (Glossocalycoideae Thorne, two tribes (Hennecartieae Philipson, Palmerieae Philipson) and one genus ( Laureliopsis Schodde) are described as new.  相似文献   

15.
Genetic heterogeneity in nine polymorphic loci is observed among Gond-related tribes in the Vidarbha region of Maharashtra. Pardhans, with their high ABO*A2 gene frequency (4.01%), low m gene frequency (57%), high P*1 gene frequency (42.7%), and high HbS trait (31.58%), differ significantly from other tribes. Per locus average heterozygosity among the studied tribes ranged from 36.24% to 40.37%, with Pardhans being more heterozygous. Analysis by FST and the empirical relationship between average allele frequencies and the ratio of within-gene to total gene diversity show that the tribes are isolated and that differentiation among them is at an early stage and approximately in conformity with expected differentiation under genetic drift. However, distances and principal components analysis reveal that Pardhans are far removed from the other tribes and from other central Dravidian tribes. Furthermore, of the various demographic parameters estimated, the high average heterozygosity in Pardhans is significantly correlated with mean marital distance (MMD), regression of MMD on wife's age, and effective population size. There is congruence between genetic and demographic data, showing that Pardhans are distinct. This conforms with Haimendorf's (1979) contention based on cultural traits that Pardhans are Gonds by historical accident and are later migrants to the Gond area from the north. The most significant and practical observation of the present study is that migration from an originally nontribal (Pardhan) to a tribal (Gond) area and admixture lead to severe disease course, differential selection pressure, and hence highly elevated HbS trait frequency.  相似文献   

16.
We report the phylogenetic utility of the nuclear gene encoding the long-wavelength opsin (LW Rh) for tribes of bees. Aligned nucleotide sequences were examined in multiple taxa from the four tribes comprising the corbiculate bees within the subfamily Apinae. Phylogenetic analyses of sequence variation in a 502-bp fragment (approx 40% of the coding region) strongly supported the monophyly of each of the four tribes, which are well established from previous studies of morphology and DNA. Trees estimated from parsimony and maximum likelihood analyses of LW Rh sequences show a strongly supported relationship between the tribes Meliponini and Bombini, a relationship that has been found uniformly in studies of other genes (28S, 16S, and cytochrome b). All of the tribal clades as well as relationships among the tribes are supported by high bootstrap values, suggesting the utility of LW Rh in estimating tribal and subfamily rank for these bees. The sequences exhibit minimal base composition bias. Both 1st + 2nd and 3rd position sites provide information for estimating a reliable tree topology. These results suggest that LW Rh, which has not been reported previously in studies of organismal phylogenetics, could provide important new data from the nuclear genome for phylogeny reconstruction.  相似文献   

17.
Minute granules of sporopollenin, called orbicules, can be observed on the innermost tangential and/or radial walls of secretory tapetum cells. Orbicules were investigated in 53 species of 34 Gentianaceae genera using light microscopy, scanning electron microscopy and transmission electron microscopy. This selection covered all different tribes and subtribes recognized in Gentianaceae (87 genera, +/-1650 species). Orbicules were found in 38 species (23 genera) distributed among the six tribes recognized in Gentianaceae. The orbicule typology is based on those described previously in Rubiaceae. Of the six orbicule types described previously, Type II orbicules are lacking. Type III orbicules are most common (17 species). Hockinia Gardner is the only representative with Type I orbicules. The number of representatives with orbicules belonging to the other orbicule types are equally distributed among the species studied: seven species possess Type IV orbicules, six species Type V and six species Type VI. The systematic usefulness of this typology is discussed in comparison with the latest systematic insights within the family, and palynological trends in Gentianaceae. Orbicule data have proven to be useful for evaluating tribal delimitation within Rubiaceae and Loganiaceae s.l.; however, they seem not to be useful for tribal delimitation in Gentianaceae. In the tribes Potalieae and Gentianeae orbicule data may be useful at subtribal level.  相似文献   

18.
Nine-hundred seventy-eight subjects from eight Mongoloid tribes of northeastern India were investigated for the distribution of hemoglobin phenotypes by starch-gel electrophoresis. The sample included 157 Khasi and 24 Bodo from Cherrapunji (Meghalaya), 148, Rengma Naga and 81 Hmar of the Cachar district of Assam, 215 Adi from different subtribes, 216 Nishi, 79 Apatani, and a mixed group of 58 individuals from several other tribes of Arunachal Pradesh in northeast India. The frequency of HBB*E was found to be very low (0.01-0.02) in the Khasi, Naga, and Hmar tribes, whereas it varied from 0.06 to 0.18 among the tribes of Arunachal Pradesh. As expected, the Bodo group had a very high frequency of HBB*E (0.38), confirming earlier reports. It appears that the lack of HBB*E in the Austro-Asiatic (Khasi) and Naga-Kuki-Chin groups is probably due to the absence of malarial selection pressure as well as to isolation from their neighbors.  相似文献   

19.
All 60 Asteraceae species sampled, i.e., two species of Bamadesioideae, 21 species in six tribes in Cichorioideae, and 37 species in nine tribes of Asteroideae, show specific patterns of autofluorescence in abaxial connective base epidermal cells. Two species of Cichorioideae and 15 species of Asteroideae have autofluorescence in adaxial epidermal cells of the connective base. Several taxonomically useful features of the connective base are identified; they include shapes of autofluorescent cells, patterns of distribution of cells with autofluorescent walls, and patterns of distribution of autofluorescence in walls. Cellular features of many species coincide with recognized generic, tribal, and subtribal classifications. The results extend Cassini's characterization of the article anthérifere and indicate that the variable features of the connective bases of stamens of Asteraceae could contribute to phylogenetic understanding.  相似文献   

20.
The mtDNA of most Native Americans has been shown to cluster into four lineages, or haplogroups. This study provides data on the haplogroup affiliation of nearly 500 Native North Americans including members of many tribal groups not previously studied. Phenetic cluster analysis shows a fundamental difference among 1) Eskimos and northern Na-Dene groups, which are almost exclusively mtDNA haplogroup A, 2) tribes of the Southwest and adjacent regions, predominantly Hokan and Uto-Aztecan speakers, which lack haplogroup A but exhibit high frequencies of haplogroup B, 3) tribes of the Southwest and Mexico lacking only haplogroup D, and 4) a geographically heterogeneous group of tribes which exhibit varying frequencies of all four haplogroups. There is some correspondence between language group affiliations and the frequencies of the mtDNA haplogroups in certain tribes, while geographic proximity appears responsible for the genetic similarity among other tribes. Other instances of similarity among tribes suggest hypotheses for testing with more detailed studies. This study also provides a context for understanding the relationships between ancient and modern populations of Native Americans. © 1996 Wiley-Liss, Inc.  相似文献   

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