The basis for the interpretation of fossil-pollen assemblages in terms vegetation and climate is present-day relationship to pollen rain. Detailed modern spectra from Tibetan Plateau are described here explore between rain vegetation. Two hundred thirty four (234) surface samples were collected moss polsters, top soil, lake sediments forests, shrublands, shrub meadows, steppes, deserts Plateau....

Lower plants generate mobile sperm cells that must reach their female counterparts by swimming. This requirement for water is a disadvantage for these plants as compared with angiosperms, for which the dry pollen attaches to a stigma and becomes hydrated, enabling the emerging pollen tube to grow in the protected environment of the pistil. After adhesion, hydration, and germination of the polle...

A decline in pollination function has been linked to agriculture expansion and intensification. In northwest Argentina, pollinator visits to grapefruit, a self-compatible but pollinator-dependent crop, decline by approximately 50% at 1km from forest edges. We evaluated whether this decrease in visitation also reduces the pollination service in this crop. We analysed the quantity and quality of ...

BACKGROUND Grass pollen allergens are a major cause of allergic respiratory disease but traditionally prescribing practice for grass pollen allergen-specific immunotherapy has favoured pollen extracts of temperate grasses. Here we aim to compare allergy to subtropical and temperate grass pollens in patients with allergic rhinitis from a subtropical region of Australia. METHODS Sensitization t...

Pollen, an extremely reduced bicellular or tricellular male reproductive structure of flowering plants, serves as a model for numerous studies covering wide range of developmental and physiological processes. The pollen development represents a fragile and vital phase of plant ontogenesis and pollen was among the first singular plant tissues thoroughly characterized at the transcriptomic level ...

In the atmosphere the importance of biological ice nuclei is still not well understood. Therefore we investigated the ice nucleation behavior of Snomax, used as a model for bacterial ice nucleation, and birch pollen washing water, used as a model for pollen induced ice nucleation. Thereby we quantified the ice nucleation behavior of the INA protein complexes controlling the ice nucleation abili...

There is minimal information about the effect of heavy metals such as lead and copper on pollen grains and pollen tubes of fruit trees. Fruit set of these plants are affected by different environmental, biological, physical and chemical factors. If one of these factors be abnormal, pollination, fertilization and fruit set and orchard yield will decrease. In polluted cities, this phenomenon is a...

The aim of the study was to analyse trends of the pollen season with its duration, start and end dates, as well as trends of the annual total pollen count and annual peak pollen concentration for the Szeged agglomeration in Southern Hungary. The data set covered an 11-year period (1997-2007) that included eight taxa and seven daily climate variables. Trend analysis was performed on both annual ...