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1.
Polytretophora macrospora is introduced based on specimens from two species ofPandanus in Seychelles. The new species is compared with currently accepted species. A key and a comparative synopsis toPolytetophora species are provided. Numerous specimens ofP. calcarata, collected on members of the Pandanaceae from Australia, Fiji, Hong Kong, Malaysia, New Caledonia, Palau, Philippines, Seychelles and Solomon Islands are also reported, along withP. dendroidea onPandanus sp. from Malaysia.  相似文献   

2.
Water in leaf axils of the screwpine Pandanus was sampled for mosquito immature stages at seventy villages in Upolu, fifty-five in Savai'i and three in Manono, the main islands of Samoa. Ten plants in every patch of Pandanus plantation were sampled at each village. Among 23,049 mosquito larvae collected from Upolu, 77% were the filariasis vector Aedes (Finlaya) samoanus, 17.7% were Ae.(Fin.)oceanicus and 5.3% were Ae.(Fin.)tutuilae. Out of 6981 larvae taken in Savai'i, 23.2% were Ae.samoanus, 67.6%Ae.oceanicus and 9.2%Ae.tutuilae. When larval counts per plant were analysed for each district, Ae.samoanus was found to predominate in Pandanus in Upolu and Ae.oceanicus in Savai'i. However, the adult density of Ae.samoanus was higher in Savai'i and this was attributed to the large areas of forests with Freycinetia for Ae.samoanus breeding. In Pandanus in Savai'i the number of Ae.samoanus was negligible. In Upolu, with more urbanization and larger plantations, there was greater breeding of Ae.samoanus in Pandanus. Two control trials were conducted against Ae.samoanus larvae in Pandanus, one using a sand culture of the parasitic nematode Romanomermis culicivorax and the other with temephos, an organophosphate insecticide. While R.culicivorax did not adapt to the leaf axil habitat, all plants were without larvae for 5 weeks after treatment with temephos.  相似文献   

3.
This is a monographic study, based upon morphology, of the species ofPandanus (sectionRykia) in India and Nepal. To the three known species are added the following new species:P. diversus, P. emarginatus, P. katatonos, P. nepalensis, andP. sikkimensis. Honorable member of the Botanical Society of Japan.  相似文献   

4.
Summary Interspecific crosses were made between 76 Tulipa gesneriana cultivars and 28 botanical Tulipa species. Tulipa gesneriana proved fully congruent (all cross-combinations giving hybrid progeny) with members of the subsection Gesnerianae, was moderately affiliated (50% of all cross-combinations giving hybrid progeny) with representatives of the subsection Eichleres, and was found to be incongruent with most other Tulipa species (except T. stapfii of the subsection Oculussolis).Relationships between T. gesneriana and some representatives of the subsection Eichleres were addressed in more detail. Seeds were harvested in all cross-combinations, but the number of seeds depended on the T. gesneriana cultivar used as the female partner. Apparently, the maternal genotype did affect pre- or post-fertilization processes. T. gesneriana was not crossable with T. kaufmanniana of the subsection Spiranthera. In this specific case, however, a bridge cross was used to overcome incongruity. For this, T. kaufmanniana was first combined with T. greigii, and the hybrid was subsequently crossed with T. gesneriana.These results demonstrate possibilities for interspecific cross-combinations in tulips and have offered opportunities for the introduction of desired new traits in the cultivated tulip.  相似文献   

5.
Species of Ficus subsection Urostigma show much overlapping variation in vegetative morphology, which often precludes correct identification of the species. The aim of this study was to describe the leaf anatomical characters and their variation and to check their suitability for identification. Included were 41 samples belonging to 25 species of subsection Urostigma, four samples belonging to two species of section Leucogyne and one specimen of Ficus glaberrima subsp. siamensis of subsection Conosycea. Transverse sections of lamina, midrib and petiole and cuticular macerations were used, and the observed anatomical characters are described for each species. On the basis of a limited number of studied samples, leaf anatomy shows little variation within each species and each species has a unique combination of character states, facilitating identification. Ficus arnottiana shows some leaf anatomical characters that are quite different from those of other members of subsection Urostigma, including a multiple epidermis and enlarged lithocysts on both sides of the leaf. Both characters are generally considered as typical for Ficus subsection Conosycea. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175 , 259–281.  相似文献   

6.
Gas chromatography–mass spectrometry analysis of seeds from 28 species of Crotalaria from Brazil (sections Calycinae, Crotalaria, Chrysocalycinae and Hedriocarpae) showed that pyrrolizidine alkaloids (PAs) are important as chemotaxonomic markers at the infrageneric level. The sections Calycinae and Crotalaria were characterized by 11-membered macrocyclic monocrotaline-type PAs. In the section Chrysocalycinae, a single species in the subsection Incanae, C. incana, showed integerrimine, a 12-membered macrocyclic senecionine-type, as main PA. The group close to the subsection Stipulosae (C. micans and C. maypurensis) showed distinctive PA patterns: C. micans presented mainly the 12-membered macrocyclic integerrimine, and C. maypurensis the unusual 7-hydroxy-1-methylene-8-pyrrolizidine. In the group close to the subsection Glaucae, the PAs with otonecine as the necine base were the main alkaloids, except in C. rufipila which showed an assamicadine-like PA (monocrotaline-type). The section Hedriocarpae showed main 12-membered macrocyclic senecionine-type PAs.  相似文献   

7.
M. Chaturvedi  D. Yunus  K. Datta 《Grana》2013,52(3):117-123
Pollen morphological studies have been carried out by SEM on 23 species of Sorghum (Gramineae) in order to resolve the exine surface patterns in sections Eu-sorghum (subsection Arundinacea-series Spontanea and Sativa and subsection Halepensia), and Para-sorghum. Basically, two exine ornamentation types have been observed viz. granular and insular. In section Eu-sorghum, series Spontanea and Sativa (of subsection Arundinacea) are heterogeneous having both types of exine pattern. In the same section, subsection Halepensia is characterised by having only a granular exine. Section Para-sorghum shows a marked pollen morphological similarity with subsection Halepensia of section Eu-sorghum. Snowden's concept that the two series Spontanea and Sativa are closely related and that the cultivated Sorghum (series Sativa) might have evolved from the wild Sorghum (series Spontanea), is supported by the present observations.  相似文献   

8.
Three new hyphomycetes colonizing dead leaves ofPandanus spp. in Mauritius are described, illustrated, and compared with related species. They areFuscophialis suttonii sp. nov.,Paraceratocladium triseptatum sp. nov., andSporidesmium paradecorosum sp. nov.  相似文献   

9.
通过标本检查,发现小五台银莲花(Anemone xiaowutaishanica W.T.WangBing Liu)与银莲花(A.cathayensis Kitag.ex ZimanKadota)属于同一种植物,故将前者处理为后者的异名。由于银莲花属于银莲花亚组[subsection Omalocarpus(DC.)Tamura],故同时将根据小五台银莲花而建立的小五台银莲花组(section Leptothece W.T.WangBing Liu)处理为银莲花亚组的异名。  相似文献   

10.
Viola uliginosa is an endangered species throughout its range in Central Europe. Based on an unusual combination of morphological characters, including a reported lack of cleistogamous (CL) flowers, it was previously placed in the monotypic subsection Repentes, section Viola. Available individual phylogenetic analyses identify V. uliginosa as a lineage deeply embedded in section Viola, but hitherto its exact position was unknown. Here we confirm the occurrence of cleistogamy in V. uliginosa. Unlike other species of section Viola, Vuliginosa produced both chasmogamous and CL flowers at the same time, not at different times of the year (seasonal cleistogamy). The two flower types differed conspicuously in morphology and microstructure, especially in size and shape of the pistil and stamens as confirmed by scanning electron microscopy. Secondly, we resolved the phylogenetic position of Vuliginosa as a lineage deeply embedded in subsection Rostratae by means of a multigene multispecies coalescent analysis using *BEAST. In this analysis, Vmirabilis and Vuliginosa were successive sisters to the rest of subsection Rostratae and, because allopolyploids exist between Vmirabilis and the last one, subsection Rostratae needs to comprise all these taxa to be monophyletic. The evolution of key morphological traits is briefly discussed.  相似文献   

11.
Alpinia newmanii, a new species from central Vietnam, is described and illustrated. A morphological comparison with the most closely related species and a key to the species of Alpinia subsection Catimbium in Vietnam are provided.  相似文献   

12.
RAPD fingerprinting was used to study species boundaries in narrowly distributed endemic species in Antirrhinum section Sempervirentia. Based on RAPD data, similarity values within species were relatively high but pair-wise similarity values among species were low. Partitioning of the overall RAPD variation using AMOVA showed that most of the variation was found among species (58.06%), whereas the remaining phenotypic diversity was distributed among populations (25.18%) and among individuals within populations (16.76%). Comparison of the matrices of geographical distances and phenetic distances (1-Dice index) among populations using the Mantel test showed a moderate, but statistically significant correlation (r=0.588, P < 0.01), suggesting that isolation by distance is responsible for the distribution of genetic variation among Antirrhinum populations. Phenetic relationships among Antirrhinum samples based on a Dice similarity matrix showed a clear taxonomic pattern, confirming the grouping of individuals within their own populations and the clustering of populations within species. Individuals of A. charidemi, A. valentinum and A. subbaeticum, from subsection Valentina, made up a discrete group, whereas the samples belonging to subsection Sempervirentia (A. petegasii, A. sempervirens, A. microphyllum, A. pulverulentum) clustered together. RAPD data are entirely congruent with the subsection classification scheme proposed by Fernández Casas (1997) in section Sempervirentia. However, A. subbaeticum, treated as a synonym of A. valentinum by Fernández-Casas (1997), showed an unique RAPD profile characterized by the highest number of fixed species-specific markers found in section Sempervirentia. Thus, although A. valentinum appeared the most closely related species to A. subbaeticum, molecular data suggested that this species merits taxonomic distinction.  相似文献   

13.
The purpose of the present study was to test the taxonomic value of sclerenchyma in distinguishing Pinus sylvestris and P. mugo, P. uncinata, P. rotundata and P. uliginosa, all representing the subsection Sylvestres within the genus Pinus. Thirty-six samples were gathered in natural populations. Every sample was represented with 30 individuals, every individual with 10 brachyblasts. Three types of sclerenchymatic cells surrounding the resin canals and four between vascular bundles were distinguished. Relations among samples and taxa were verified using discriminant analysis and clustering based on Euclidean distances. The types of sclerenchymatic cells surrounding the resin canals and located between the vascular bundles differentiate the compared taxa when used as average frequencies but are extremely variable and do not allow the classification of every individual. The study demonstrated that the type of sclerenchymatic cells surrounding the resin canals and between the vascular bundles in needles could have an important taxonomic value in distinguishing the taxa of two-needle pines of the subsection Sylvestres in Europe at the population level. The distinguishing of individuals was difficult because of very high variation of sclerenchyma characters.  相似文献   

14.
The examination of several taxa from various tropical regions of the world, previously classified as Phyllanthus urinaria L., indicates that they do not belong to a single species. On the basis of morphology, cytology, genetics, and biometry, a new classification is presented in which the collective species P. urinaria, or “urinaria complex,” is elevated to the subsection level: Phyllanthus subsection Urinaria. Within the subsection, two subgroups may be recognized on the basis of seed coat ornamentation. Each of these lines is represented by two species which differ from each other in chromosome number: P. embergeri nov. spec. (2n = 100) and P. nozeranii nov. spec. (2n = 50) in the “spiraled” line, P. hookeri Muell. Arg. (2n = 100) and P. urinaria L. (2n = 50) in the “radiated” line. In the latter species, which has undergone diversification, two subspecies may be distinguished: P. urinaria urinaria and P. urinaria nudicarpus subspec. nova.  相似文献   

15.
Podandrogyne chocoensis and Podandrogyne caucana, two new species of Cleomaceae from western Colombia and eastern Panama, are described and illustrated. In view of their probable relationship to each other, but somewhat isolated position with respect to the majority of species of Podandrogyne, the new subsection Breviracemosae is proposed.  相似文献   

16.
Pandanus is well represented in Papua New Guinea with over 66 species growing from sea level to 3,000 m. The territory of the Wopkaimin, who live at the headwaters of the Ok Tedi in the Star and Hindenburg Mountains, is particularly rich in wild and domesticated species ofPandanus. Detailed analysis of the species in classification, ecology, subsistence, ritual and material culture not only establishesPandanus as a locally significant plant resource but also contributes to the comparative understanding of ethnobiological systems. A close correspondence with botanical taxa of generic and specific rank and an absence of the most inclusive taxon term for plant are 2 cross-culturally important findings substantiated in WopkaiminPandanus taxonomy.  相似文献   

17.
Meconopsis wilsonii subsp. orientalis Grey‐Wilson, Rankin & Wu, a new subspecies from north‐east Yunnan Province of China, is described and illustrated. Its relationships with other members of subsection Eupolychaetia, particularly M. wallichii, M. violacea and the other subspecies of M. wilsonii, are discussed.  相似文献   

18.
The plant genus Silene has become a model for evolutionary studies of sex chromosomes and sex‐determining mechanisms. A recent study performed in Silene colpophylla showed that dioecy and the sex chromosomes in this species evolved independently from those in Silene latifolia, the most widely studied dioecious Silene species. The results of this study show that the sex‐determining system in Silene otites, a species related to S. colpophylla, is based on female heterogamety, a sex determination system that is unique among the Silene species studied to date. Our phylogenetic data support the placing of S. otites and S. colpophylla in the subsection Otites and the analysis of ancestral states suggests that the most recent common ancestor of S. otites and S. colpophylla was most probably dioecious. These observations imply that a switch from XX/XY sex determination to a ZZ/ZW system (or vice versa) occurred in the subsection Otites. This is the first report of two different types of heterogamety within one plant genus of this mostly nondioecious plant family.  相似文献   

19.
《Phytochemistry》1987,26(4):973-974
Intact Hawaiian Metrosideros trees in situ release mercury vapour from their branches at rates as high as 5–6 μg/kg/hr (dry wt). This compares well with the emission of mercury from detached leaves or shoots of woody perennials Aleurites, Leucaena and Pandanus. The emission rates appear to be related to soil mercury content.  相似文献   

20.
A new coprophilous species, Coprinellus radicellus, is presented and described on the basis of morphological characters and a species phylogeny inferred from ITS1–5.8S–ITS2 and beta-tubulin gene sequences. The species is characterized by lageniform pileo- and caulocystidia, 8- to 11-μm long ellipsoid basidiospores with a central germ-pore, globose cheilocystidia, an often rooting stipe, the lack of pleurocystidia and velar elements. These characters distinguish C. radicellus from all other described species in subsection Setulosi. It comes closest to C. brevisetulosus (Arnolds) Redhead, Vilgalys & Moncalvo and C. pellucidus (P. Karst.) Redhead, Vilgalys & Moncalvo both morphologically and phylogenetically, but is distinct from both. Another five representatives of morphologically recognizable groups of subsection Setulosi were included in the phylogenetic analyses and found were distinct from C. radicellus, both morphologically and phylogenetically. To date, this new species is known only from Scandinavia, which is surprising in view of the uniform geographical distributions of most setulose Coprinellus species. A key to coprophilous taxa of Coprinellus with pileo- and caulocystidia is presented. Three new combinations are proposed.  相似文献   

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