BACKGROUND Peltophorum pterocarpum and Delonix regia are dominant avenue trees in the city of Kolkata in India. They are well adapted to the humid tropical climate and also grow commonly in different parts of the country. Their pollen grains are reported to be airborne. OBJECTIVE The aim of this study was to conduct an aerobiological survey in Kolkata to determine the concentration and season...

abstract to study the effects of xenia and methaxenia on the pistachio nut, 4 male genotypes from among all male genotypes provided by rafsanjan pistachio research institute were selected. the flowering period of the chosen genotypes was the same as 3 female cultivars of kalleghoochi, ohadi, and ahmadaghaii. by using split plot in the form of completely randomized blocks design, we conducted va...

Pollen grains of Arabidopsis (Arabidopsis thaliana) contain two haploid sperm cells enclosed in a haploid vegetative cell. Upon germination, the vegetative cell extrudes a pollen tube that carries the sperm to an ovule for fertilization. Knowing the identity, relative abundance, and splicing patterns of pollen transcripts will improve our understanding of pollen and allow investigation of tissu...

BACKGROUND In Central Europe, hazel (Corylus sp.) pollen is considered to be an important aeroallergen in early spring. OBJECTIVE This study examines hazel pollen levels in Poznań, western Poland, and the clinical relevance of this aeroallergen in the city. METHODS Corylus pollen data (1996-2010) were obtained by volumetric spore trap located near the centre of Poznań. Clinical data (2006-2...

air pollutants are reported to increase the specific ige response to allergens. clinical tests and immonoblotting were performed with pollen grains of spartium junceum. to identify allergens and to determine the effect of air pollutants on the allergenicity of the pollen extracts, the pollen extracts were injected intraperitoneally and intracutaneously to guinea pigs. injection of the pollen ex...

Plane-trees are widely grown in Spain as ornaments. This taxon releases large amounts of pollen into the air and this pollen type seems to have proved implications on pollinosis. The aim of this study was to analyse airborne Platanus pollen content in the air of C6rdoba (South-western Spain) over the last 10 years, and its distribution in different areas of the city, as well as to consider poss...

Hourly measurements of pollen near-surface concentration and lidar-derived profiles of particle backscatter coefficients and of volume and particle depolarization ratios during a 5-day pollination event observed in Barcelona, Spain, between 27 – 31 March, 2015, are presented. Maximum hourly pollen concentrations of 4700 and 1200 m h were found for Platanus and Pinus, respectively, which represe...

Tapetal programmed cell death (PCD) is a prerequisite for pollen grain development in angiosperms, and cysteine proteases are the most ubiquitous hydrolases involved in plant PCD. We identified a papain-like cysteine protease, CEP1, which is involved in tapetal PCD and pollen development in Arabidopsis thaliana. CEP1 is expressed specifically in the tapetum from stages 5 to 11 of anther develop...

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...

We present the results of pollen analysis performed on an ice core recovered from Nevado Sajama, Bolivia, dated to 25 ka BP. Low pollen concentrations from 25 to 15 ka BP are consistent with the scenario of an expanded ice cap surrounded by sparse vegetation and cold conditions on the Altiplano during the Last Glacial Maximum. After 15 ka BP, more pollen is present and percentages show vegetati...