To assess the feeding habits of the Bonin Flying Fox (Pteropus pselaphon, Layard, 1829) pollen analysis was conducted on the faeces of the animals from Minami-Iwo-To Island and Chichi-jima Island, Ogasawara Archipelago. In total 23 plant species and two fern species were represented by the pollen and spores recovered from the faeces samples collected on the two islands. Notably, pollen of only one species was recovered on Minami-Iwo-To Island: Pandanus sp., while on Chichi-jima Island seven (5.4±1.3) species were identified from the pollen which had passed through the gut of P. pselaphon. The species represented include first records for the flowers of Syzygium sp. and Pandanus sp. as part of the diet of Bonin Flying Foxes. The pollen assemblage in the faeces also suggests that some alien plant species such as Agave americana, Ficus microcarpa and Syzygium jambos are major elements in the diet of the Bonin Flying Fox on Chichi-jima Island. In addition, on both islands, fern spores were found frequently in the faeces of these animals, suggesting that ferns also provide a major food resource (for example, Asplenium setoi), especially on Minami-Iwo-To Island. This paper documents for the first time, that ferns form part of the diet for P. pselaphon, the Bonin flying fox.

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In order to estimate the identity and source of the grass species component of airborne pollen and its constituents, a vegetation analysis was conducted in the central part of Morioka city during early April and early July in 2006 and in 2007. The number of pollen grains produced per flowering head was also counted for grass species observed at study sites in 2007. According to the results of a vegetation species count for one square meter 10 grass species, with a total of 819 flowering heads, were recorded in 2007. The 10 species were dominated by 47% of sweet vernalgrass, 19% of tall fescue, 13% each of orchardgrass and Kentucky bluegrass. Notably, these four species represented 92% of the total flowering heads. Number of florets, number of anthers, and number of pollen per anther were counted for all ten species. The numbers of pollen per flowering head calculated using these data were 17.28×10^6 for orchardgrass, 9.10×10^6 for tall fescue, 1.61×10^6 for Kentucky bluegrass 1.28×10^6 for sweet vernalgrass. From these data, the number of pollen produced per square meter from 1st April to 10th July was estimated as 4304×10^6; being composed of 44% of orchardgrass, 34% of tall fescue, 11% of sweet vernalgrass and 4% of Kentucky bluegrass, and 7% other species.

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Autofluorescence characteristics and pollen diameter size ranges for Cryptomeria japonica (L.f.) D. Don and Chamaecyparis obtusa (Siebold & Zucc.) Endl. pollen collected from various regions in Japan were recorded and compared. The fluorescence intensity of C. japonica and C. obtusa pollen varies depending on their locality. Analysis using either the ratio of blue/red (B/R) fluorescence spectra or pollen diameter did not indicate any significant difference among samples of C. japonica collected from the different study regions (except for those from different areas of Hokkaido). In the case of C. obtusa pollen, there was also no significant difference in the colour among the samples from the different study regions when evaluated in terms of either B/R ratio or pollen diameter. However, by evaluating these samples using both B/R ratios and diameter sizes, pollens of the C. japonica and C. obtusa can be differentiated. Humidity (30% and 65%) had some significant effects on the autofluorescence (blue, red, green) intensities, however, it did not have any effects on the B/R ratio and diameter size of C. japonica and C. obtusa pollens. These results suggest that samples of C. japonica and C. obtusa pollen, with the exception of those from Hokkaido, might be identifiable by using both their B/R ratios and diameter sizes. In this study we propose a detection system, which distinguish samples of pollens using their B/R ratio (based on their autofluorescence spectra) and pollen diameter size differences. This system could be used to identify dispersed pollens of various species of Cupressaceae, Taxodiaceae, etc. in Japan.

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Subfamily Arbutoideae (Ericaceae) comprises four genera (Arbutus, Arctostaphylos, Comarostaphylos and Ornithostaphylos) and 81 species. We have examined the pollen morphology of 17 species from three of these genera: Arbutus, Arctostaphylos, Comarostaphylos, using light microscopy (LM) and scanning electron microscopy (SEM) and also, for selected species, transmission electron microscopy (TEM). The Arbutoideae are generally stenopalynous: the four 3-colpor(-oid)ate grains are united in compact rounded permanent tetrads. No pollen morphological characters or character combinations distinguish Arbutoideae within the Ericaceae. However, within the subfamily, Arctostaphylos and Comarostaphylos commonly have smaller pollen tetrads with a thin perforated septum, while Arbutus pollen tetrads are usually larger and characterized by a thicker septum without distinct perforations. The rugulate apocolpial ectexine sculpture of Arctostaphylos is usually less distinct than the coarser rugulate ectexine often observed for the pollen of Arbutus and Comarostaphylos

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To understand the characteristics of diurnal changes in hourly counts for the pollen of Cryptomeriaceae dispersed in the atmosphere of Kobe, we investigated the relationship between hourly pollen counts and wind direction in 2002, 2003 and 2005. Stratified by four wind directions and four time periods (thus divided into 16 sections), the pollen count was statistically analyzed by the Kruskal-Wallis rank sum test and multiple comparison. When the wind direction was from the north to northwesterly from the Tanba and Chugoku mountains (the major sources of the pollens), their counts were characterized by the follow: they tended to increase between 13:00 and 18:00 hours in comparison with other wind directions and other time periods and decrease between 01:00 and 06:00 hours, in contrast to other wind directions. According to Bonferroni correction, a significantly decrease (p<0.05) was found with the northeast to east wind in 2003 and 2005. In some instances, however, the intra-day counts reached the highest from 01:00 to 06:00 hours when the approach of a low atmospheric pressure caused the wind to shift from the northeast to east direction. These findings indicate that the pollen count in the winds coming from the direction of the main source of pollen was affected differently during different time periods. It was also found that the pollen count could increase after midnight as a result of specific meteorological conditions.

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The adhesion of fullerene nano-particles to Cryptomeria japonica, Chamaecyparis obtusa and Camellia japonica pollen was investigated. Adhesion of fullerene nano-particles caused interference to the autofluorescence of the pollen. The degree of adhesion of the particles to the pollen varied, being dependent on the type of fullerene nano-particles used. This could be attributed to differences in the composition of fullerene nano-particles supplied by the manufacturers. Furthermore, germination of C. japonica pollen was inhibited by the adhesion of fullerene nano-particles.

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