The relationship between pollen germination and the dynamic organization of the actin cytoskeleton during pollen germination is a central theme in plant reproductive biology research. Maize (Zea mays) pollen grains were implanted with 30 keV argon ion (Ar(+)) beams at doses ranging from 0.78 x 10(15) to 13 x 10(15) ions/cm(2). The effects of low-energy ion implantation on pollen germination via...

pollen grains of five olive cultivars (olea europaea l .) were examined, using scanning electron microscopy (sem) for identification purposes. four measurments, polar axis (p), equatorial diameter (e), p/e ratio and exine patterns were made. forty pollen grains of each cultivar were viewed before finally selecting a representative pollen grain. polar diameter ranged between 22.76 μm for the...

Pollen limitation is a key assumption of theories that explain mast seeding, which is common among wind-pollinated and woody plants. In particular, the pollen coupling hypothesis and pollination Moran effect hypothesis assume pollen limitation as a factor that synchronizes seed crops across individuals. The existence of pollen limitation has not, however, been unambiguously demonstrated in wind...

In order to evaluate eight different protein sources in honey bee nutrition, some experiments were conducted as a completely randomized designs with four replicates and three steps incubator, field and overwintering in Isfahan region. Protein sources were lentil flour, soybean flour, soybean meal, bread yeast, wheat gluten, skim milk powder, fish meal and Pollen. Results showed that the longevi...

Pollen monitoring is of great importance for the prevention of allergy. As this activity still is largely carried out by humans, there is an ever increasing interest in the automation of pollen monitoring, with the goal of reducing monitoring time in order to plan more efficient treatments. In this context, an original device based on computer vision is developped. In this paper, the colour seg...

Double fertilization of flowering plants depends on the targeted transportation of sperm to the embryo sac by the pollen tube. Currently, little is known about the underlying molecular mechanisms that regulate pollen germination and pollen tube growth in maize (Zea mays). Here, a maize pollen-predominant gene Zm908, with several putative short open reading frames (sORFs), was isolated and chara...

Competition among pollen grains for the chance to fertilize ovules typically involves two stages: arrival times on stigmas and/or the growth of pollen tubes through styles. In a previous study of Hibiscus moscheutos, we found that individual pollen donors often differed in pollen tube competitive ability. Here we determined whether short delays in pollen arrival time altered the average success...

To clarify the relationship between pollen density and gametophytic competition in Pyrus pyrifolia, gametophytic performance, gibberellin metabolism, fruit set, and fruit quality were investigated by modifying P. pyrifolia pollen grain number and density with Lycopodium spores. Higher levels of pollen density improved seed viability, fruit set, and fruit quality. Treatments with the highest pol...