Hypothesis: Sex allocation theory predicts that the pollen–ovule ratio should decrease linearly with increasing pollen size among seed plants (Charnov, 1982). Data examined: We retrieved data for pollen–ovule ratio, pollen size, pollen grain number, and mating system from published literature for 311 angiosperm plant species. Methods: We used model II regressions on cross-species data as well a...

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...

studies of postmeiotic chromosomes have been impeded by the thick exine of immature pollen grains. chromosome staining of immature and adult pollen grains through conven-tional acetocarmine procedure is tedious and often leads to unsatisfactory results. an acetocarmine stain, used in conjugation with carnoy’s solution as fixative for 72 hrs or until the chlorophyll-containing tissues of spike b...

Background. With an increase in Japanese cedar and cypress (JC) pollinosis, the relationship between JC pollen and atopic dermatitis (AD) has been studied. Some reports suggest that JC pollen can be one exacerbating factor for AD, but there has been no report that discusses JC pollen counts relating to AD symptom flare although actual airborne JC pollen counts can widely fluctuate throughout th...

Tropical paleoecologists use a combination of mud-water interface and modern pollen rain samples (local samples of airborne pollen) to interpret compositional changes within fossil pollen records. Taxonomic similarities between the composition of modern assemblages and fossil samples are the basis of reconstructing paleoclimates and paleoenvironments. Surface sediment samples reflect a time-ave...

During pollen development, transcription of a large number of genes results in the appearance of distinct sets of transcripts. Similar mRNA sets are present in pollen of both mono- and dicotyledonous plant species, which indicates an evolutionary conservation of genetic programs that determine pollen gene expression. In pollen, regulation of gene expression occurs at the transcriptional and pos...

Theatmosphericpollen loadsofHobart,Tasmania,Australia,weremonitoredbetweenSeptember2007andJuly 2009. To examine the match of the airborne pollen composition with the flowering duration of their contributing plants, the phenology of native and non-native plants in various habitats near the pollen-trapping site was undertaken between August 2008 and July 2009. The pollen load was found to have a ...

Worldwide, 400 million people suffer from hay fever and seasonal asthma. The major causative agents of these allergies are pollen specific proteins called the group-1 grass pollen allergens. Although details of their antigenicity have been studied for 40 years with an eye towards immunotherapy, their function in the plant has drawn scant attention. Zea m 1 constitutes a class of abundant grass ...

Viking Age ring fortresses were some of the largest construction projects in Danish prehistory. In this article we reconstruct amount turf and timber used Borgring fortress estimate resource area needed to supply building materials. Using REVEALS pollen data modelling, quantify regional oak land cover area. The results show that even though was built an open cultural landscape, sufficient for w...