The maize (Zea mays) pollen-predominant gene Zm908, a novel small-peptide gene, was reported to play critical roles in pollen germination and pollen tube growth in our previous work. In this study, we aimed to explore the regulatory mechanism of Zm908. The putative promoter of Zm908 was cloned and analyzed. The activity analysis of a series of promoter truncations in different tissues of transg...

* The effects of actinomycin D and cycloheximide on RNA and protein synthesis were investigated during pollen tube development of Pinus bungeana. * RNA and protein contents, protein expression patterns, cell wall components and ultrastructural changes of pollen tubes were studied using spectrophotometry, SDS-PAGE electrophoresis, Fourier transformed infrared (FTIR) microspectroscopy and transmi...

In parts of the world where teosinte and maize are grown in close proximity, there is concern about gene flow between them. Pollen is the primary vehicle for gene flow. Quantifying the biophysical properties of pollen, such as its settling speed and dehydration rate, is important for evaluating outcrossing potential. These properties were measured for teosinte (Zea mays subsp. parviglumis) poll...

Pollen analysis is seen as a largely qualitative method, but recent developments in analytical techniques, technologically and theoretically, have directed a move towards a greater use of quantitative interpretation. Use of these new methods allows more detailed information to be obtained from pollen data and in turn widens the scope for use of this technique. It is often assumed that pollen an...

Low seed yield is a limiting factor for cross breeding and hybrid seed production in cyclamen. This study was performed to investigate pollen germination and its relation to cross-pollination success and fruit set in this plant. In order to achieve a high level of pollen germination, the effect of different concentrations of chemical compounds were examined on in vitro pollen germination of cyc...

The present study shows the results of monitoring the atmospheric pollen in the atmosphere of an area of natural vegetation, the Hornachuelos Natural Park, Cordoba, southern Spain, during a six years (1998-2003). Special attention was paid in the seasonal and intra-diurnal characteristics of airborne allergenic pollen. During this period, 31 pollen types were described, some of them rare in aer...

We report on the in situ characterization of tree pollen molecular composition based on Raman spectroscopy. Different from purification-based analysis, the nondestructive approach allows (i) to analyze various classes of molecules simultaneously at microscopic resolution and (ii) to acquire fingerprint-like chemical information that was used for the classification of pollen from different speci...

Double fertilization in flowering plants requires the delivery of two immotile sperm cells to the female gametes by a pollen tube, which perceives guidance cues, modifies its tip growth direction, and eventually enters the micropyle of the ovule. In spite of the recent progress, so far, little is known about the signaling events in pollen tubes in response to the guidance cues. Here, we show th...

Previous studies have shown that ragweed pollen arrives in Poland from sources in the south, in Slovakia, the Czech Republic, Hungary and Austria. It is likely that ragweed pollen also arrives from sources in the southeast (e.g. Ukraine). This hypothesis was investigated using 13 years of pollen data and back-trajectory analysis. Ambrosia pollen data were collected at three sites in Poland, Rze...

This paper discusses the characteristic air mass types over the Carpathian Basin in relation to plant pollen levels over annual pollination periods. Based on the European Centre for Medium-Range Weather Forecasts dataset, daily sea-level pressure fields analysed at 00 UTC were prepared for each air mass type (cluster) in order to relate sea-level pressure patterns to pollen levels in Szeged, Hu...