Pollen quantity, viability and germination of four genotypes of Rosa dumalis and R. villosa were investigated. The number of anthers per flower were 90.3 in genotype 4 (Rosa villosa) and 116.4 in genotype 1 (Rosa dumalis). Genotype 1 showed the highest pollen viability on the basis of both TTC and IKI tests. Most of the rose species are diploid but there are several species with higher ploidy l...

Upon germination, pollen forms a tube that elongates dramatically through female tissues to reach and fertilize ovules. While essential for the life cycle of higher plants, the genetic basis underlying most of the process is not well understood. We previously used a combination of flow cytometry sorting of viable hydrated pollen grains and GeneChip array analysis of one-third of the Arabidopsis...

Pollen is a unique plant tissue that potentially can be used and manipulated to the advantage of the geneticist, breeder, physiologist, or germplasm curator. Since pollen of most species is haploid and each cell is independent, pollen has the potential to provide a microbial-like system for evaluation, assay, and selection. Whatever the interest and use, the viability of the pollen is necessary...

Pollen rains may temporally mitigate nutritional limitations experienced by terrestrial and aquatic detritivores by supplying stoichiometrically balanced food during periods of detritivore growth and development (spring-summer). This may affect the functioning of food webs and thus influence fundamental processes, e.g., by enabling fungi to decompose nutritionally scarce litter. Nutritional lim...

Butterflies of the genus Heliconius are well known for their peculiar habits of utilizing pollen as a source of amino acids. Saliva plays a major role in the process of extracting amino acids and proteins from the pollen grains. In this investigation, we obtained samples of saliva from adult Heliconius melpomene by placing pumpkin pollen or fine glass-beads on the proboscis, which stimulates th...

Bee product mugwort is identified as being at the origin of allergic accidents but the biological potency of Artemisia contained in bee pollen is not well known. In this experiment, Artemisia mass was identified in bee pollen mass and after having calculated the proportion of Artemisia using the bee pollen melissopalynology spectrum. Skin reactivity to Artemisia was assessed by measuring wheal ...

pollen grain morphology of 15 taxa of the hedysareae tribe distributed throughout iran was studied using light and electron microscopy to identify major taxonomical characteristics of pollen grains. the pollen grains were tricolpate and tricolporate, prolate and perprolate. the ectocolpi were elongated, shallow or deep, narrowing at the poles. the colpus membrane was covered by large granules. ...

We present novel results of pollen analyses performed on a 10m firn core retrieved from Alto dell’Ortles glacier (3840ma.s.l.), Eastern Italian Alps, in 2009. The objective was to identify and quantify pollen grains retained in the ice to detect annual and interannual variations in the pollen spectra, thus enabling construction of an accurate pollen-based timescale. Up to now, this has been ach...

The artificial germination of plant pollens has met with varying success. As a whole, the pollen of the Gramineae has proved very difficult to germinate. While experiments with the pollen of many plants have resulted not only in ready germination but in satisfactory methods of preserving the pollen for considerable periods of time, the results with many of the Gramineae have been far from satis...

Exposure to bioaerosol allergens such as pollen can cause exacerbations of allergenic airway disease (AAD) in sensitive populations, and thus cause serious public health problems. Assessing these health impacts by linking the airborne pollen levels, concentrations of respirable allergenic material, and human allergenic response under current and future climate conditions is a key step toward de...