Numerous Pollen Research Articles

MORPHOLOGICAL CHARACTERISTICS AND PROPAGATION OF HELICIA COCHINCHINENSIS LOUR. (PROTEACEAE): A NATIVE SHRUB OF THE NORTHERN HEMISPHERE

The micromorphological characteristics of leaves, flowers, and seeds were observed for Helicia cochinchinensis, which is the only member of the Proteaceae family to be represented in Japan. Leaf surface was found to be hypostomatic with a rough cuticular topography lacking pubescences. The abaxial leaf surface always presented numerous stomata with a particular tendency for stomatal density to be higher towards the tip portion of the leaf. An enlarged stomatal view showed numerous stomata spread in a radial disposition (actinocytic), and their guard cells were surrounded by a structure with a circular form. Flowers were composed of four tepal segments positioned in a linear manner which, during anthesis, break and curl backwards until they touched the style base. The long and slender stamens were adnate to the corolla through a short filament, and retained numerous pollen grains of a triangular form. The lower part of the pistil consisted of a superior ovary surrounded by ovate hypogynous glands, and longitudinal ridges were detected at the upper stylar part at the stigmatic surfaces. Stomata were also present in both the anther abaxial surface and in the perianth. In addition, the perianth adaxial surface showed only a few stomata having varied morphological features. These findings confirm the presence of some anatomical traits common among its species. Fruits and seeds differed significantly in length, diameter and weight and these characteristics appeared to be related to the original harvest sites. The embryo was undifferentiated as the plumule and radicle could not be recognized. The seeds germinated two months after sowing at 25°C and one month later at 20°C. The requirement for low temperature is not considered a determinant for seed germination. For cutting propagation, the application of auxin Oxiberon (1% IBA) in a talc treatment gave a high rooting rate and increased the number of roots per cutting in comparison to IBA applied as dipping treatment at 150 ppm.

Pollen analyses of honey from Finland

The present study reports results of qualitative melissopalynological analyses of Finnish honey between the years 2000–2007 and changes in its pollen content from the period 1960–2007. Altogether the pollen content of 734 honey samples was analysed with an average of 415 pollen grains counted from a sample. Pollen of Trifolium repens type, Rubus spp., Salix spp. and the Brassicaceae family were present in more than 90% of the samples, and these pollen types were also found in the highest proportions. Annual variation in the relative amounts of the most numerous pollen types could be as high as 10%. On the basis of the pollen spectra of the honey samples, four regions of forage plants for bees could be identified in Finland. In the period between 1960 and 2007, the most marked change observed was that the percentage of the Trifolium spp. pollen type had decreased from 70% to 10%, while the proportions of Brassicaceae and Rosaceae pollen types showed a corresponding increase.

Cordaitalean Seed Plants from the Early Permian of North China. II. Reconstruction of Cordaixylon tianii

From a single Early Permian locality in the Taiyuan Formation of northern China, a new whole‐plant cordaitalean is reconstructed and named Cordaixylon tianii (B. Tian and S.‐J. Wang) S.‐J. Wang and J. Hilton sp. nov. The reconstruction is based on pairs of plant organs found in organic attachment, supplemented with cases where two or more co‐occurring morphospecies share distinctive anatomical features. Stems have sympodial primary vascular architecture with endarch primary xylem maturation of the cauline bundles, which surround a septate pith. Leaf traces are endarch, most diverging from the pith margin as double bundles (less frequently singly) and bearing leaves in 3/8 and 5/13 phyllotaxis. Leaves are long and straplike, resembling those of the previously reconstructed Cordaixylon dumusum Rothwell and S. Warner, but with a geniculate posture that justifies their segregation as Cordaites tianii S.‐J. Wang and J. Hilton sp. nov. Both male and female cones are compound, borne irregularly as epicormic branches, and when isolated conform to the morphogenus Cordaitanthus. Pollen cones with numerous pollen organs borne on apically concentrated fertile scales are largely consistent with the morphospecies Cordaitanthus concinnus Delevoryas, but subtle distinctions permit their description as C. tianii S.‐J. Wang and J. Hilton sp. nov. Ovulate cones are described as Cordaitanthus shanxiensis S.‐J. Wang and J. Hilton sp. nov.; each cone contains several cardiocarpalean ovules that have a distinctive tuberculate integumentary structure and are assignable to the morphospecies Cardiocarpus tuberculatus S.‐J. Wang, J. Hilton, and B. Tian. The reconstructed plant most closely resembles C. dumusum from the Late Pennsylvanian of North America, but (often subtle) diagnostic characters are well distributed across the organs of the two conceptual whole plants, permitting confident distinction at species level. The plant is reconstructed as a large, suberect or fully erect shrub.

Searching for a Manageable Pollinator for Acerola Orchards: The Solitary Oil-Collecting Bee <I>Centris analis</I> (Hymenoptera: Apidae: Centridini)

Acerola (Malpighia emarginata DC; Malpighiaceae) is an important fruit crop in Brazil. Among its pollinators, Centris (Heterocentris) analis (F.) stands out due to its abundance at flowers and prompt acceptance of trap-nests. For the first time, we propose the commercial use of Centris bees as orchard pollinators. To develop protocols for rearing and management of these bees, we analyzed trap-nest acceptance, brood-cell construction, and larval diet in Acerola orchards. Although Centris species, in general, use numerous pollen host plants, females of C. analis showed remarkable flower fidelity to Acerola for pollen supply when nesting in the orchard. Such fidelity was previously expected only for floral oil collection. The ease of acceptance of trap-nests by females of C. analis, their prolonged yearly activity period, multivoltine life history, and high pollinator efficiency characterize C. analis as an excellent potentially manageable pollinator in Acerola orchards.

Floral adaptations to nocturnal moth pollination in Diplomorpha (Thymelaeaceae)

AbstractMany members of the family Thymelaeaceae are highly praised and economically important for the production of fragrant scent, but little is known about the ecological significance of their secondary metabolites. To explore the potential role that secondary metabolites play in pollination, we studied the pollination systems of five Diplomorpha species in Japan by investigating their floral morphology and flower‐visiting insect fauna. We also analyzed the composition and temporal emission pattern of floral volatiles in one of the species to determine if there were any characteristics associated with the observed flower visitors. In Diplomorpha, anthesis began at dusk and various nocturnal moths were found visiting the flowers, often carrying numerous pollen grains on their proboscises. However, no hawkmoths were observed visiting Diplomorpha flowers. Diurnal insects visited the flowers less often, and most of them had short mouthparts and did not effectively contact the stigma. The floral scent of Diplomorpha sikokiana was released only at night when the moths were active and consisted mainly of monoterpenes and benzenoids, with a small amount of a sesquiterpene. The present study is the first to examine the pollination system of Diplomorpha and suggests that these plants exhibit a range of floral features associated with pollination by nocturnal moths. The single ovule in Diplomorpha flowers probably does not favor pollination by optimally foraging bees, which are more likely to cause intraplant pollen transfer, and might have facilitated adaptation to pollination by nocturnal moths, despite the lower number of pollen grains that are carried by these insects.

Household Economy, Long-Term Change, and Social Transformation: The Bronze Age Political Economy of Northwestern Europe

In this article I examine how long-term economic strategies in the Bronze Age of northern Europe between 2300 and 500 BCE transformed the environment and thus created and imposed new ecological constraints that finally led to a major social transformation and a "dark age" that became the start of the new long-term cycle of the Iron Age. During the last 30 years hundreds of well-excavated farmsteads and houses from south Scandinavia have made it possible to reconstruct the size and the structure of settlement and individual households through time. During the same period numerous pollen diagrams have established the history of vegetation and environmental changes. I will therefore use the size of individual households or farmsteads as a parameter of economic strength, and to this I add the role of metal as a triggering factor in the economy, especially after 1700 BCE when a full-scale bronze technology was adopted and after 500 BCE when it was replaced by iron as the dominant metal. A major theoretical concern is the relationships between micro- and macroeconomic changes and how they articulated in economic practices. Finally the nature of the "dark age" during the beginning of the Iron Age will be discussed, referring to Sing Chew's use of the concept (Chew 2006).

Emerging pollen allergens

Numerous pollen allergens have been reported over the last few years. Most of them belong to well-known families of proteins but some others constitute the first member of new allergenic families. Some of the factors that can contribute to the detection and identification of new pollen allergens are: a) advances in the technology tools for molecular analysis; and b) the deep knowledge of many allergenic sources. The combination of these factors has provided vast information on the olive pollen allergogram and the identification of minor allergens that become major ones for a significant population. The close taxonomical relationship between olive tree and ash -both Oleaceae- has permitted to identify Fra e 1 (the Ole e 1-like allergen) in ash pollen and to detect the presence of protein homologues of Ole e 3 and Ole e 6. In the other hand, extensive areas of south Europe are suffering an increasing desertification. As a consequence of this, new botanical species are spontaneously growing in these areas or being used in greening ground programs: Chenopodium album and Salsola kali are some examples recently recognized as allergenic woods. The identification of the complete panel of allergens from the hypersensitizing sources might help to develop more accurate diagnosis, and efficient and safer therapy tools for Type-I allergic diseases.

The use of fossilized honey for paleoecological reconstruction: A palynological study of archeological material from Georgia

Palynological analysis of the organic contents of ceramic pots from the Kodiani burial mound, which is dated as 27th-25th centuries B.C., revealed that they contained honey. The samples are extremely rich in excellently preserved pollen grains, including numerous pollen grains of insect-pollinated plants. Such characteristics are typical of palynological assemblages from honey. The palynological assemblages from three pot fragments studied are dominated by pollen grains of Rosaceae; however, they differ from one another in the subdominants. The discovery of several kinds of honey testifies to the presence of well-developed beekeeping in the time of the Early Kurgans. Agriculture, with a significant role of wheat, was also developed in the region of Georgia under study. According to the composition of the palynospectra, the ecological conditions that existed during the epoch studied differ significantly from the present day.

Refshøjgård – Et bemærkelsesværdigt gravfund fra enkeltgravskulturen

Refshøjgård – Et bemærkelsesværdigt gravfund fra enkeltgravskulturen

¿Polinización por medio de alas de abejas en Mexacanthus (Acanthaceae)?

El género monotípico Mexacanthus de la familia Acanthaceae es endémico del centro occidente de México, donde está representado por la especie M. mcvaughii T.F. Daniel. La estructura de la flor es poco usual, con las anteras y el estigma en posición lateral y una barrera de néctar que no se abre sin el ejercicio de fuerza. El estudio de la polinización muestra que las flores son visitadas principalmente por el colibrí tijereta esmeralda Chlorostilbon canivetii (Lesson) y por el abejorro Xylocopa mexicanorum (Cockerell). Ambas especies abren sin problemas la barrera de néctar y se comportan como polinizadores. Los colibríes transfieren el polen en su área auricular; la abeja lo hace en sus alas, en las cuales lleva numerosos granos. La polinización por alas anteriormente se conocía sólo de lo registrado en representantes del grupo de las mariposas.

Biologia da polinização e sistema reprodutivo de Psychotria barbiflora DC. (Rubiaceae)

O estudo foi realizado no período de abril/1999 a setembro/2000, no Parque Estadual Dois Irmãos, Recife (PE) Brasil, um remanescente de floresta Atlântica. Psychotria barbiflora é espécie subarbustiva (0,5-2,0m alt.), com período de floração entre abril e julho e frutificação de junho a setembro. A espécie apresentou heterostilia do tipo distilia, com inflorescências terminais, pendentes, envoltas por brácteas que apresentaram coloração esverdeada durante a floração e tornaram-se arroxeadas na fase de frutificação. As flores abriram por volta das 4h30min e duraram até às 13h. O volume médio de néctar foi ca. 0,8 e 0,6µl e a concentração de açúcares, aproximadamente 22 e 24%, nas flores longistilas e brevistilas, respectivamente. Os morfos florais apresentaram semelhança em relação ao tamanho da corola, entretanto nas flores brevistilas os grãos de pólen foram maiores e em menor quantidade quando comparado com as flores longistilas. Psychotria barbiflora é melitófila, sendo polinizada por três espécies de abelhas, as quais coletaram néctar e pólen, e por uma espécie de vespa que coletou apenas néctar, em ambos os morfos florais. Baseando-se nos resultados das polinizações manuais e no crescimento dos tubos polínicos, pode-se concluir que esta espécie apresenta auto-incompatibilidade do tipo esporofítica, com formação de frutos apenas nos cruzamentos intermorfos.

Obligate pollination mutualism in Breynia (Phyllanthaceae): further documentation of pollination mutualism involving Epicephala moths (Gracillariidae)

This paper reports obligate seed-parasitic pollination mutualisms in Breynia vitis-idea and B. fruticosa (Phyllanthaceae). The genus Breynia is closely related to Glochidion and Gomphidium (a subgenus of Phyllanthus), in which pollination by species-specific, seed-parasitic Epicephala moths (Gracillariidae) have been previously reported. At night, female Epicephala moths carrying numerous pollen grains on their proboscises visited female flowers of B. vitis-idea, actively pollinated flowers, and each subsequently laid an egg. Examination of field-collected flowers indicated that pollinated flowers of B. vitis-idea and B. fruticosa almost invariably had Epicephala eggs, suggesting that these moths are the primary pollinators of the two species. Single Epicephala larvae consumed a fraction of seeds within developing fruit in B. vitis-idea and all seeds in B. fruticosa. However, some of the fruits were left untouched, and many of these had indication of moth oviposition, suggesting that egg/larval mortality of Epicephala moths is an important factor assuring seed set in these plants. The overall similarity of the specialized floral structure among Breynia species may indicate that this pollination system is fairly widespread within the genus.

Cross-reactivity of pollen allergens.

Pollen cross-allergenicity has practical implications on the management of inhalant allergy, in both evaluation and therapy, especially with allergen vaccine immunotherapy. The study of cross-reactivity among pollen allergens has expanded beyond investigation of crude extracts to the characterization and cloning of numerous pollen proteins. In this review, the interrelationships between these pollen allergens in the context of botanical systematics are examined, to provide a framework for cross-reactivity understanding. Recommendations for choices in evaluation and therapy are given.

Pollination by fungus gnats in four species of the genus Mitella (Saxifragaceae)

The first example of pollination by fungus gnats in the eudicots is reported. The genus Mitella (Saxifragales) is characteristically produces minute, inconspicuous, mostly dull-coloured flowers with linear, sometimes pinnately branched, petals. To understand the function of these characteristic flowers, we studied the pollination biology of four Mitella species with different floral traits and different sexual expression: dioecious M. acerina, gynodioecious M. furusei var. subramosa, and hermaphroditic M. stylosa var. makinoi and M. integripetala. Flower-bagging experiments showed that wind pollination did not occur in the dioecious and gynodioecious species. Two years of observations of flower visitors at six study sites in Japan revealed that the principal pollinators of all four Mitella were specific species of fungus gnats (Mycetophilidae), which landed on the flowers with their long spiny legs settling on the petals. Characteristically, numerous pollen grains were attached to the fungus gnats in specific locations on the body. Although, on average, 1.3–2.6 fungus gnats visited each inflorescence per day, the fruit set of both bisexual and female flowers exceeded 63%. These results suggest that fungus gnats are highly efficient pollinators of Mitella spp., and that Mitella flowers are morphologically adapted to pollination by fungus gnats.

Harmonized methods of melissopalynology

Pollen analysis of honey, or melissopalynol-ogy, is of great importance for quality control.Honey always includes numerous pollen grains(mainly from the plant species foraged by honeybees) and honeydew elem ents (like wax tubes,algae and fungal spores) that altogether providea good fingerprint of th e environment where thehoney comes from. Pollen analysis can thereforebe useful to determine and control the geograph-ical and botanical origin of honeys even if sen-sory and physico-chemical analyses are alsoneeded for a correct dia gnosis of botanical ori-gin. Moreover, pollen analysis provides someimportant information about honey extractionand filtration, fermentation (Russmann, 1998),some kinds of adulteration (Kerkvliet et al

Petrified araucarian remains from Sonajori, Rajmahal Basin, India

Permineralized araucarian ovulate and pollen cones are described here for the first time in close association from Early Cretaceous intertrappean rocks of the Sonajori Locality in the Rajmahal Basin, Jharkhand. These cones were found associated with woods and leafy shoots bearing spirally arranged falcate to oblanceolate leaves. The leaf, in longitudinal section shows epidermis followed by parenchymatous mesophyll and transfusion tissue. Ovulate cones, elliptical-spherical in shape, with spirally attached bracts and ovuliferous scales bearing mostly one and rarely two ovules/seeds per cone scale complex. Cone scale complex is characterised by the presence of "circa" (ligular sulcus). In one specimen, cross-section shows close association of numerous pollen grains with the cone scale complex of the cone indicating the preservation of cone at pollination stage. In another specimen, cross-section shows cone scale with oblong inverted ovule/seed, ovule integument/seed testa with three distinct layers, nucellus free except at chalazal end, shrunken at micropylar region and the presence of an embryonic tissue shows a post fertilisation stage of cone preservation. Anatomical features of these cones indicate various stages of cone maturity. The microsporangiate cone elongated in shape, in tangential view shows microsporophylls as well as circular-oval sporangia in cross-section. Transverse-sections of cone shows a central axis surrounded by numerous elongated narrow sporangia in longitudinal section and rhomboidal tip of the microsporophyll. The microsporophyll shows only parenchymatous tissue in sectional view of distal part: dispersed circular alete pollen grains are found associated with ovulate/seed cone and sterile shoots. Morphological and anatomical features of all the Indian species of araucarian cone described earlier are also critically assessed.

A redescription of Podosporites parvus (Couper) Mildenhall emend. Mildenhall & Byrami from the Early Pleistocene, and late extinction of plant taxa in northern New Zealand

Numerous specimens of the conifer pollen grain Podosporites parvus, recorded at c. 1.32 Ma in the Pliocene‐Pleistocene Puketoka Formation, suggest that the parent plants inhabited the fringes of lowland, coastal hardwood/podocarp forest. This pollen type has a botanical affinity with Microcachrys and Microstrobos (Podocarpaceae), which are prostrate to small shrubs currently inhabiting alpine and sub‐alpine rocky outcrops, especially in wet areas, and around mountain tarns in Australia. The deposition site also features pollen of Nothofagus (Fuscospora), Dacrydium cupressinum, and several other tall trees, but is dominated by Nestegis. It also contains two extinct mesothermal taxa. The presence of a member of the Australian alpine conifer Microcachrys/Microstrobos group in an Early Pleistocene lowland pollen record from northern New Zealand suggests that such prostrate to small shrub‐like conifers may have occupied different geographic and ecological ranges then than they do today. Moreover, it indicates that the vegetation assemblages have no modern New Zealand equivalent. P. parvus is re‐described and diagnosis emended to highlight its distinctive irregular sacci and granulate‐rugulate cappa, characteristics that distinguish it from other trisaccate grains attributed to Podosporites. The discovery of numerous pollen grains of an extinct species in these Early Pleistocene sediments is additional evidence that northern North Island was the last refuge for many New Zealand plants as they dwindled into extinction with the onset of cooler conditions.

Pollen coat proteins after two-dimensional gel electrophoresis and pollen wall ultrastructure of Secale cereale and Festuca pratensis

This paper reports results of two-dimensional gel electrophoresis analysis of pollen coat and pollen protoplast proteins of self-incompatible and self-fertile Secale cereale as well as pollen collected from Festuca pratensis populations and selected self-sterile plants. Washing pollen 10 times in isotonic buffer showed that the first and second fractions contained the majority of the pollen coat proteins. Results of protein analysis are discussed against the background of pollen wall ultrastructure. A fraction of peptides found in the pollen coat were also present in the protein patterns of protoplasts; however, numerous pollen coat peptides were not detected in the protoplast and vice versa. The self-incompatible S. cereale had 23 pollen coat peptides and 46 from protoplasts that differed in molecular weight (MW) and isoelectric point (IP) in comparison to those of pollen coat and protoplasts of self-fertile S. cereale. Similarly, self-sterile F. pratensis had 60 pollen coat peptides and 11 protoplast peptides different from those of the self-sterile/self-fertile F. pratensis. The pollen coat fraction of the self-incompatible S. cereale and the self-sterile plants of F. pratensis had three peptides with very similar MW and IP, whereas in their protoplasts two peptides with similar MW and IP were found. The possible relationship between pollen ultrastructural organisation and rate of protein elution is discussed.

Distribution and ecology of parent taxa of pollen lodged within the Latin American Pollen Database

The cornerstone of palaeoecological research, concerned with vegetation dynamics over the recent geological past, is a good understanding of the present-day ecology and distribution of the taxa. This is particularly necessary in areas of high floral diversity such as Latin America. Vegetation reconstructions, based on numerous pollen records, now exist with respect to all major vegetation associations from Latin America. With this ever-increasing number of sedimentary records becoming available, there is a need to collate this information and to provide information concerning ecology and distribution of the taxa concerned. The existing Latin American Pollen Database (LAPD) meets the first of these needs. Information concerning the ecology and distribution of the parent taxa responsible for producing the pollen, presently lodged within the LAPD, is the focus of this paper. The ‘dictionary’ describes the ecology and distribution of the parent taxa responsible for producing pollen identified within sedimentary records. These descriptions are based on a wide range of literature and extensive discussions with members of the palaeoecological community working in different parts of Latin America investigating a range of different vegetation types.

Effects of Holocene Alnus Expansion on Aquatic Productivity, Nitrogen Cycling, and Soil Development in Southwestern Alaska

Numerous pollen records provide evidence for the widespread range expansion of Alnus throughout Alaska and adjacent Canada during the middle Holocene. Because Alnus can fix atmospheric N2, this vegetational change probably had a profound effect on N availability and cycling. To assess this effect, we analyzed a sediment core from Grandfather Lake in southwestern Alaska for a suite of geochemical indicators, including elemental composition, biogenic silica (BSi) content, and carbon (C) and nitrogen (N) isotopes of organic matter. These data, in conjunction with a pollen record from the same site, are used to infer biogeochemical processes associated with the mid-Holocene Alnus expansion. The increase in Alnus pollen percentages from 10% to 70% circa 8000-7000 BP (14C years before present) suggests the rapid spread of Alnus shrub thickets on mountain slopes and riparian zones in the Grandfather Lake region. Coincident with this vegetational change, the mean value of the sediment BSi content increases from 20.4 to 106.2 mg/g, reflecting increased diatom productivity within the lake as a result of Alnus N2 fixation in the watershed soils and the associated N flux to the lake. Elevated aquatic productivity at this time is also supported by increased percentages of organic C and N, decreased C:N ratios, and decreased values of δ 13C. Furthermore, the δ 15N values of sediments increase substantially with the establishment of Alnus shrub thickets, suggesting enhanced N availability and accelerated N cycling within the lake and its watershed. Superimposed on a general trend of soil acidification throughout the postglacial period, soil acidity probably increased as a result of the Alnus expansion, as can be inferred from decreasing ratios of authigenic base cations to allogenic silica (Si) and increasing ratios of authigenic aluminum (Al) to allogenic Si. The ultimate cause of these mid-Holocene ecosystem changes was an increase in effective moisture in the region.