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1.
Sylvia Feuer 《Grana》2013,52(4):225-242
This is the first of two papers detailing pollen morphology and evolution with the tribe Embothrieae comprising eight genera and ca. 56 spp. The present paper examines pollen of subtribes Buckinghaminae (Buckinghamia; 2 spp., Opislhiolepis; 1 sp.), Stenocarpinae (Strangea; 3 spp.), Stenocarpus (ca. 27 spp.) and Lomatiinae (Lomatia; ca. 12 spp.) in the light microscope and scanning and transmission electron microscopes. Pollen is medium-sized, oblate, foveolate to microreticulate to reticulate, and predominantly columellate with a complex modified postvestibulate aperture morphology. Pollen data indicate ties between Lomatia and Stenocarpus on the one hand and Stenocarpus and Strangea on the other. Though Buckinghamia and Opislhiolepis have been placed in the same subtribe, the unique combination of pollen features in each suggests only a remote relationship to each other as well as to remaining Embothrieae. Comparisons to the remaining genera of Embothriae (Embothrium, Oreocallis, Telopea) and overall analysis of pollen evolution within the tribe are detailed in the subsequent paper.  相似文献   

2.
O. R. Vidal 《Genetica》1984,65(3):235-239
A list is presented containing data on chromosome numbers and sex determining mechanisms of 90 species of Argentina beetles, belonging to the families Staphylinidae (2 spp.), Meloidae (3 spp.), Elateridae (1 sp.), Coccinellidae (5 spp.), Tenebrionidae (11 spp.), Scarabaeidae (30 spp.), Cerambycidae (3 spp.), Chrysomelidae (27 spp.), Curculionidae (7 spp.) and Lampyridae (1 sp.), Asphaera t-album (Chrysomelidae) had n=10+X+6y; in Epicauta atomaria (Meloidae) individuals with 2 n=22, 21 and 20 were found.This work was supported by grants of National Research Council of Argentina (CONICET) and SUBSYT.  相似文献   

3.
In order to contribute to the knowledge of monofloral honeys from northern Africa, a number of 116 honey samples were collected in three areas in the northern region of Algeria and analysed for their melissopalynological characteristics. Fifty-one of them proved to be monofloral and were mainly from four botanical sources: Eucalyptus spp., Hedysarum coronarium, Pimpinella anisum and Citrus spp. The honeys could be differentiated from honeys from neighbouring countries by the presence of specific associated pollen. Besides the main pollen species, the characteristic 12 pollen types in the four monofloral Algerian honeys in this study were: Acacia sp., Brassicaceae, Carduus sp., Centaurea sp., Convolvulus arvensis, Eucalyptus spp., Olea europaea, Papaver rhoeas, Pimpinella anisum, Trifolium spp., Rubus sp. and Vicia sp. Regional differences in the pollen composition were also observed. Characteristic associated pollen grains in the north-western region were Acacia sp., Brassicaceae, Carduus sp. and Centaurea sp., in the central north region Coriandrum sativum, Echium sp. and Trifolium spp. and in the north-eastern region Apiaceae.  相似文献   

4.
A broad survey of the Asteraceae, involving visual characters, was undertaken to ascertain the occurrence of possible Kranz-type (C4) plants. One hundred and seven taxa representing 51 genera were examined by mass spectrometry for their 13C/12C ratios in dried leaf tissue. Species possessing the high 13C/12C ratio typical of the Kranz syndrome were found in genera belonging to the following tribes: Heliantheae (subtribe Coreopsideae)—Chrysanthellum (4 spp.), Eryngiophyllum (1 sp.), Glossocardia (1 sp.), Glossogyne (1 sp.), Isostigma (5 spp.); Tageteae—Pectis (21 spp.); and Helenieae—Flaveria (4 spp.). The only genus to possess both C3 and C4 species was Flaveria in which all but four species appear to possess a C3-type metabolism. When appropriate, the phyletic input of these data is discussed.  相似文献   

5.
The sugar and osmophilic fungal composition of soils amended with five organic substrates (newspaper, orange peel, bromegrass leaves, wheat straw and wood sawdust) was estimated after 2, 4, 6, 8 and 10 weeks using the dilution plate method on glucose and 50% sucrose Czapek's agar media. Wheat straw was the best substrate for total counts of both sugar and osmophilic fungi followed by newspaper, bromegrass leaves, wood sawdust and orange peel. Wood sawdust supported the highest average counts of total sugar fungi, Fusarium, Mucor, Scopulariopsis, Trichoderma and Trimmatostroma spp.; Newspaper, of Aspergillus (8 spp.), Penicillium (4 spp.) and Chaetomium sp. bromegrass leaves of Cladosporium sp., Humicola sp. and Sporotrichum sp.; orange peel, ofAlternaria sp., Circinella sp. and Stachybotrys sp.; and wheat straw, of Botryotrichum sp. and Myrothecium sp. Bromegrass leaves and orange peel supported the highest average counts of total osmophilic fungi, Aspergillus (10 spp.), Cladosporium sp. Paecillomyces sp. and Rhizopus sp.; and of Stemphylium sp., Trichoderma sp., Humicola sp. and Circinella sp. respectively; wheat straw, of Epicoccum sp., Scopulariopsis sp. and Trichothecium sp.; newspaper, of Penicillium (4 spp.) and Alternaria sp.; and wood sawdust of Curvularia sp. and Fusarium (3 spp.). The best colonizers throughout the experimental periods were Aspergilus and Penicillium spp.  相似文献   

6.
Pollen apertures were analyzed among the subfamilies Persoonioideae (seven genera; ca. 95 spp.), Sphalmioideae (one genus; one spp.), and Camarvonioideae (one genus; two spp.). Pollen was examined by light microscopy, cryosection, and transmission electron microscopy. Completed studies of pollen apertures among Grevilleoideae (ca. 40 genera; ca. 800 spp.), one of two major subfamilies in Proteaceae, provide a basis for comparison and analysis of aperture evolution among these subfamilies. Aperture characters within Persoonioideae are unique among Proteaceae examined to date. Five distinct aperture types occur among the three subfamilies, three of which (Placospermum, Persoonia, Bellendena) are restricted to Persoonioideae. Sphalmioideae and Camarvonioideae each exhibit a unique aperture organization. The most primitive aperture organization, and one unique to Placospermum, exhibits three main features: 1) a thin, granular endexine continuous around the grain; 2) a heterogeneous foot layer throughout the grain with increased disruptions at the aperture; and 3) only slight differences in exine characters between apertural and nonapertural regions. The Persoonia aperture type represents the next stage of aperture evolution which involves loss of endexine, restriction of a heterogeneous foot layer to the aperture, and marked differences in exine characters between apertural and nonapertural regions. The uniformly homogeneous ektexine in both nonapertural and aperture regions in Bellendena has developed independently. Sphalmium exhibits a primitively thin granular endexine though the restriction of endexine to the aperture is a derived condition. Carnarvonia exhibits several pollen characters also found among Grevilleoideae including: 1) a homogeneous nonapertural ektexine; 2) a slightly heterogeneous apertural ektexine; 3) a lamellate/granulate endexine organized into irregularly shaped “clumps” clustered around the aperture; and 4) a clear demarcation between apertural and nonapertural exine. These characters support the hypothesis that Carnarvonia may have diverged early from the pre-Grevilleoids.  相似文献   

7.
Extensive material on parasitoids of the family Ichneumonidae reared from gall-making sawflies on Salix is identified. The general host—parasite list includes 75 species of hosts—Pontania (40 spp.), Phyllocolpa (21 spp.), Euura (14 spp.), their food plants (33 species of Salix), and their parasitoids of the family Ichneumonidae; many data on hosts and parasitoids are recorded for the first time. The complex of ichneumonids on gallforming sawflies is composed of about 45 species belonging to 15 genera of 6 subfamilies. The annotated list of about 30 species of ichneumonids (except for species of Saotis) reared from gall-making sawflies is given with data on the literature, studied material, distribution, and hosts. Two new species Anoncus gallicola sp. n. and Rhinotorus brachycerus sp. n. are described. A key to the species of the Ichneumonidae of this complex is given.  相似文献   

8.
Various aspects of the reproductive biology of the Andean-disjunct genusRetanilla (DC.) Brongn. were studied in populations ofR. trinervia andR. ephedra located in central Chile and ofR. patagonica in southern Argentina. Flowering extends from -austral- winter (early spring inR. patagonica) to early summer. The small, white, entomophilous flowers are incompletely protandrous and last four to five days. A weak pleasant odor along with nectar and pollen attract thirty-seven diurnal insect species, ten of which are probable pollinators: these include the honey bee, eight species of solitary bees pertaining toAnthophoridae (1 sp.),Colletidae (3 spp.) andHalictidae (4 spp.), and a nemestrinid fly. Although flower morphology and individual flower phenology do not fully prevent self-pollination (and geitonogamy can easily take place), the level of autogamy is low. Therefore, some self-incompatibility mechanism seems operative inRetanilla. Fruit set of open-pollinated flowers is extremely low, with a maximal value of c. 3% inR. patagonica. In this species, ripe fruits contain on average 1.37 viable seeds. Predispersal (maternal) reproductive success (percent ovules becoming viable seeds) is 2.3%. For medium to full-sized individuals this corresponds to c. 4600 potential offspring per year. As presently known,Retanilla is a reproductively uniform group, in which the Andean disjunction seems to have exerted no particular impact, which is consistent with the view that pollination generalization exerts some stabilizing influence on floral morphology and other reproductive traits.Retanilla expresses a basic rhamnacean set of traits (including protandry and self-incompatibility) showing also high pollen production and secondary pollen presentation. The latter two traits seem characteristic of theRetanilla-Trevoa clade, suggesting that a trend to increased male effort and, perhaps, dependence upon polleneating has evolved within the tribe Colletieae.  相似文献   

9.
Palynological assemblages are reported for the first time for the La Irene Formation, southwestern Santa Cruz Province, Argentina. This unit represents the sedimentation during a regressive period from transitional or delta-plain to fluvial environments. Palynological assemblages are scarce and moderately well preserved. They mainly consist of continental elements (wood remains, cuticles, spores and pollen grains) with scarse marine palynomorphs (dinoflagellate cysts). The spore-pollen assemblages are dominated by fern spores, followed by angiosperm and gymnosperm pollen grains. Bryophyte spores and fungal remains are also present. Among ferns, Cyatheaceae and spores of Laevigatosporites, of uncertain affinity, are dominant. Of the angiosperm pollen, those of Chloranthaceae (Clavatipollenites sp.) and Arecaceae (Arecipites spp., Longapertites sp., Spinizonocolpites hialinus Archangelsky and Zamaloa) are the most abundant. Pollen of Liliaceae (Liliacidites spp.), Proteaceae (Proteacidites sp., Peninsulapollis gillii (Cookson) Dettmann and Jarzen, Retidiporites camachoii Archangelsky) and Ericaceae (Ericipites scabratus Harris) are also present. Gymnosperm pollen is represented by Podocarpaceae (Podocarpidites spp.) and Ephedraceae (Equisetosporites sp.). These palynological suites would represent a fern-angiosperm dominated coastal vegetation, developed under warm and at least locally humid climatic conditions. La Irene Formation is considered Maastrichtian in age based on stratigraphic evidence, which is, in turn consistent with the ages suggested by the species ranges and the similarities observed with others previously described assemblages. This is the southernmost record of Spinizonocolpites, similar to the extant mangrove palm Nypa.  相似文献   

10.
Ambrosia sp. pollen in Switzerland   总被引:1,自引:0,他引:1  
The presence of Ambrosia sp. pollen is very irregular inSwitzerland. South to the Alps (Ticino), the yearly meanquantities (1993 to 1997) reach 535 pollen grains in Lugano and114 in Locarno. To the West, 205 pollen grains of Ambrosiasp. are observed as yearly mean total in Geneva. In La Chaux-de-Fonds(100 a.s.l.), a yearly mean of 86 pollen is reached, 66 inNeuchâatel, 59 in Payerne and 74 in Basel. In the Swiss RhoneValley, in Visp, this yearly mean reaches 30 pollen ofAmbrosia sp. A little more in the center of the country, inBern, 31 pollen are monitored as yearly mean quantity. In therest of the helvetic territory, in the North and in the East, theyearly mean are below 15 pollen grains. Since 1991–1992, anincrease has been observed essentially in Ticino, in Geneva,Neuchâatel and La Chaux-de-Fonds. The presence of Ambrosiasp. pollen is often noticed in case of strong west or south-westwind flowing, probably coming from the Rhôone Valley and theBresse in France and the Po Valley in Italy.  相似文献   

11.
Pollen grains in the atmosphere of Didim, collected using a Durham sampler, were investigated in 2004 and 2005. Weekly pollen grains per square centimetre were calculated. Over a period of 2 years, 17,518 pollen grains/cm2 belonging to 40 taxa and unidentified pollen grains were recorded. In 2004, 9,879 pollen grains were counted per cm2, and in 2005 the value was 7,639 per cm2. The majority of pollen grains investigated were Pinus spp. (45.58%), Cupressaceae/Taxaceae (13.49%), Olea spp. (9.19%), Platanus spp. (7.62%), Gramineae (6.33%), Pistacia spp. (4.34%), Morus spp. (3.81%), Quercus spp. (2.02%), Abies spp. (1.39%), and Plantago spp. (1.11%). During the month of April, 40.46% of total pollen grains were recorded. According to our results, pollen season durations for the dominated pollen grains in Didim were: the 7th–33rd weeks for Pinus spp., nearly the whole year except summer for Cupressaceae/Taxaceae, the 17th–29th weeks for Olea spp., the 10th–24th weeks for Platanus spp., the 8th–46th weeks for Gramineae, the 8th–20th weeks for Pistacia spp., the 11th–21st weeks for Morus spp., the 17th–21st weeks for Quercus spp., the 9th–27th weeks for Abies spp., and the 7th–26th weeks for Plantago spp.  相似文献   

12.
In August 1998, 72 benthic stations were sampled off the northwestern coast of Mexico. A baseline survey of the polychaete macrofauna was carried out for the southernmost portion of the Southern California Bight (SCB) region. Spatial patterns of polychaete assemblages were characterized to determine evidence of environmental impact from point sources of wastewater discharge near the study area, and to define a standard against which to detect future change. A total of 4231 polychaetous annelids representing 38 families and 210 species were identified, which constituted 53% of the total macrofauna. Families with highest species richness were Spionidae (18 spp.), Onuphidae (15 spp.), and Terebellidae (14 spp.). Species with greatest abundances were Spiophanes duplex (490 ind.), Spiophanes fimbriata (330 ind.), Lanassa sp. D (209 ind.), Pectinaria californiensis (138 ind.), and Euclymeninae sp. A (124 ind.). Based on polychaete assemblages, communities for the southernmost SCB were found to be composed primarily of non-opportunistic species, and no numerically dominant species were found. High values of polychaete diversity (H) indicated the majority of the area of study could be considered an undisturbed environment. Principal Components Analysis (PCA) applied to environmental and faunistic parameters indicated depth, organic carbon, and sediment grain size as the main influences determining the polychaete faunal communities.  相似文献   

13.
The population dynamics of potentially harmful phytoplankton in the semi-closed, coastal Bizerte Lagoon, Tunisia, in the south-western Mediterranean, were examined from November 2007 to February 2009 at six sampling stations, three situated in areas of mussel and oyster farming. The harmful species monitored included the potential producers of amnesic shellfish poisoning (Pseudo-nitzschia spp.), paralytic shellfish poisoning (Alexandrium spp.), diarrheic shellfish poisoning (Dinophysis spp. and Prorocentrum spp.), ichthyotoxins (Cochlodinium polykrikoides, Akashiwo sanguinea and Karenia mikimotoi), yessotoxins (Gonyaulax spinifera) and the discolouration of water (Neoceratium lineatum and Protoperidinium sp.). These were numerically dominated by potentially toxic species of the diatom genus Pseudo-nitzschia, which were present year-round at all stations. Prorocentrum spp., Dinophysis spp. and Neoceratium lineatum were the most abundant and recurrent harmful dinoflagellates, exhibiting their highest densities at the shellfish farming stations. Alexandrium spp. bloomed only on one occasion, reaching its highest densities at a shellfish farming station. Canonical correspondence analyses revealed significant relationships between the harmful phytoplankton species monitored and the environmental conditions. The widespread distribution of harmful phytoplankton in Bizerte Lagoon, with the permanent presence of Pseudo-nitzschia spp. and the high frequency of dinoflagellate blooms in the shellfish areas, suggests a potential risk of shellfish poisoning events in the region.  相似文献   

14.
Twenty five surface samples/moss cushions were collected for palynological analysis from open areas of Reasi District, Jammu and Kashmir (India). These samples were used to investigate the relationships between extant vegetation and modern pollen spectra, which serve as modern analogue for the reliable ecological interpretation of fossil pollen records. The present vegetation in the region comprises tropical dry deciduous forests and subtropical pine forests with scattered stands of oak. The pollen analysis reveals that Pinus sp. (average 69% in the pollen assemblages), amongst the conifers, dominates the pollen rain, which can be attributed to its high pollen productivity and exceptional pollen dispersal efficiency. Cedrus sp. and Podocarpus sp. pollen contribute with an average of 16 and 5% to the total pollen rain. Other conifers such as Picea sp., Abies sp., Juniperus sp. and Tsuga sp., as well as broad-leaved taxa such as Quercus sp., Alnus sp., Betula sp., Carpinus sp., Corylus sp., Juglans sp., Ulmus sp., Salix sp., Elaeocarpus sp., Mallotus sp. and Aesculus sp., have lower averages of 1 to 4.5% in the total pollen rain which could be either due to their poor pollen dispersal efficiency or to the poor preservation in the samples. Tubuliflorae (average 25%), Poaceae (average 6.26%), Cerealia and other crop plants (average 7.68%) are other prominent taxa in the pollen rain. The nearly complete absence of members of tropical dry deciduous forests in the pollen spectra likely is due to the fact that most species in this vegetation type are not wind pollinated.  相似文献   

15.
No previous studies have been conducted on the diversity and population of arbuscular mycorrhizal fungi (AMF) in relation to organically grown chili (Capsicum frutescens L.) in Thailand. This study was carried out to investigate the diversity and status of AMF populations at four organically managed farms in Ubon Ratchathani and Sisaket provinces. The effects of each AMF species on the growth and nutrient uptake of chili grown in sterile, organically managed soil were determined. Fourteen AM fungal taxa belonging to the genera Acaulospora (4 spp.), Entrophospora (1 sp.), Glomus (7 spp.) and Scutellospora (2 spp.) were found. Among these, Glomus was the dominant genus found at all sites, followed by Acaulospora. The spore density and root colonization of AMF on chili did not vary significantly among the sites. The effects of ten selected AMF species on the growth of chili showed that Gl. clarum RA0305 increased the growth, flowering, and fruit production of chili, and also increased the P uptake significantly, compared to non-mycorrhizal plants. This fungus showed the highest potential as a promoter of growth, flowering and yield in organically managed chili production.  相似文献   

16.
对菅属(ThemedaForsskal)的命名与合法性历史进行了考订,确定合法的属并列出了异名录;鉴于原AnthistiriaLinn.f.属较庞杂,属的概念(范畴)有较大变化,本文采用P.Forsskal及E.Hackel和W.D.Clayton的Themeda属的范畴,对已发表的原归用于Anthistiria和Themeda等属的种(双名)逐一作了考订,以明确它们的隶属关系并转隶于10个不同的局;对Themedan属自P.Forsskal(1775)建立以来的系统分类研究状况作简短的回顾,并对所存在的问题作了简述.  相似文献   

17.
The general model of seasonal phytoplankton succession in temperate lakes suggests that winter phytoplankton growth is minimal under ice-cover. However, some studies have found diverse phytoplankton communities during winter. The primary objectives of this study were to determine the species composition and the changes in the winter phytoplankton community structure under the ice. For 2 consecutive winters, phytoplankton samples were collected under ice-cover at 4 sites on 3 lakes in Arrowwood National Wildlife Refuge (ANWR), near Pingree, North Dakota. Ninety taxa were identified and enumerated. Densities of several of these taxa frequently exceeded 106 cells l–1. The winter phytoplankton communities in these lakes were dominated by flagellates, principally cryptomonads, a synurophyte (Synura uvella), small chrysophytes (Chrysococcus spp., Kephyrion spp.) and a dinoflagellate (Peridinium aciculiferum), as well as non-flagellate microchlorophytes (Monoraphidium spp., Ankistrodesmus spp., and Pseudodictyosphaerium sp.), a cyanobacterium (Gloeocapsa aeruginosa) and centric diatoms (Stephanodiscus minutulus, S. parvus and Cyclotella meneghiniana).  相似文献   

18.
Adem Bicakci 《Biologia》2006,61(4):457-461
In this study, pollen grains were identified using Durham sampler in the atmosphere of Sakarya in 2000 and 2001. During these two years, a total of 10 805 pollen grains were recorded. A total of 5 386 pollen grains per cm2 were recorded in 2000 and a total of 5 419 pollen grains per cm2 in 2001. Pollen fall in the years 2000–2001 comprised grains belonging to 40 taxa and some unidentified pollen grains. Of these taxa, 22 belonged to arboreal and 18 taxa to non arboreal plants. Total pollen grains consisted of 69.45% grains from arboreal plants, 28.11% grains from non-arboreal plants and 2.44% unidentified pollen grains. In the region investigated, Gramineae, Pinus sp., Quercus sp., Cupressaceae/Taxaceae, Salix sp., Platanus sp., Populus sp., Carpinus sp., Fagus sp., Chenopodiaceae/Amaranthaceae, Xanthium sp., Moraceae, Corylus sp., Fraxinus sp., and Urticaceae released the greatest amount of pollen. The season of maximum pollen fall was from March to May, with a prevalence of arboreal pollen in the first months, and of pollen from non-arboreal plants in the last months of the year.  相似文献   

19.
Thirty-three angiosperm pollen species are here reported from mid-Cretaceous deposits of the Kachaike Formation, Austral Basin, southern Argentina. Clavatipollenites is the most abundant angiosperm genus, with six well-defined morphological groups recognised on the basis of their reticulum morphology and sculpture. Pollen of eudicots are scarce, represented by tricolpate (Psilatricolpites spp. and Tricolpites spp.), tricolporoidate and tricolporate morphotypes (Dryadopollis spp.). Increasing complexity in the aperture structure is seen throughout the sequence; tricolpate and tricolporoidate forms are recorded in almost all samples, while tricolporate pollen grains are restricted to the middle and upper levels of the unit. The high species richness and abundance of monocolpate-ulcerate angiosperm related to monocots or magnoliids sensu lato recorded in the unit is comparable to that previously recognised in other assemblages from the early and middle Albian of the southern (e.g. Australia) and northern hemispheres (e.g. Western Portuguese basin, Europe). The recorded increase in the number of angiosperm species towards the middle and upper parts of the Kachaike Formation, with the presence of monocolpate, tricolpate, tricolporoidate and tricolporate pollen, suggests an early-early middle Albian age for these parts of the unit, in agreement with the early Albian age proposed for its basal levels on the basis of dinoflagellates.  相似文献   

20.
The pollen content of 31 honey samples from 19 different apiaries of El Hierro (Canary Islands) were subject to qualitative and quantitative melissopalynological analysis. The quantitative analysis demonstrated that 13% of the honey belonged to Maurizio Class I (<2?000?grains), 68% to Class II (2?000–10?000?grains) and 19% to Class III (10?000–50?000?grains). The pollen density ranges from 1?042?grains/g of honey to 24?478?grains/g with an average of 7?471?grains/g. According to the qualitative analysis, six honeys were typified as unifloral and 25 as multifloral. The unifloral honey samples were broken down as follows: two of heather (Erica arborea L.), two of Chamaecytisus proliferus (L. f.) Link‐type (“tagasaste”), one of Fabaceae (Genisteae sp.) and one of Lamiaceae Origanum vulgare L. ssp. virens (Hoffmanns. &; Link) Ietsw.‐type (thyme: Micromeria hyssopifolia Webb &; Berthel.). Honeydew elements were practically absent. Sixty‐nine pollen types were identified belonging to 42 families. The number of pollen types range between 18 and 39 (mean of 27.42). Foeniculum vulgare Mill.‐type pollen is present in all the samples. Galactites tomentosa Moench‐type, Echium plantagineum L., Echium L. sp., Bituminaria bituminosa (L.) C. H. Stirt., Chamaecytisus proliferus ‐type and Origanum vulgare ssp. virens ‐type pollen were found in 96.8% of the samples. The sensorial analysis indicated that honey types are generally of good quality, because 62% were evaluated as very high (16%), high (23%), and good (23%).  相似文献   

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