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Pollen dispersal was estimated in two test plots in a hinoki (Chamaecyparis obtusa) seed orchard using a chloroplast DNA marker, the spacer region between thetrnD andtrnY genes, and SSCP (single strand conformation polymorphism). In Plot 1, 2,020 seeds from 40 trees within 30 m of the marker
tree were analyzed using the PCR-SSCP method. In Plot 2, 1,850 seeds from 37 trees were analyzed in the same manner. The results
revealed that the maximum pollen dispersal distance in the two plots exceeded 25 m. Pollen dispersal appeared to be inversely
proportional to the distance from the marker tree. The effective pollen dispersal was suggested to be less than about 20 m
in a mature hinoki seed orchard. Adjacent trees had an excessive influence when the pollen density was increased by artificial
flower stimulation. Therefore, it was suggested that seed production better resembles ideal random mating when carried out
as naturally as possible. In conclusion, the SSCP chloroplast DNA marker was a useful tool for amassing basic information
on pollen management in seed orchards of coniferous species. 相似文献
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Yasuyuki Tachiki Tetsuhiko Yoshimura Hisashi Hasegawa Tomonori Mita Tetsuro Sakai Futoshi Nakamura 《Journal of Forest Research》2005,10(6):419-427
The objectives of this study were to determine Global Positioning System (GPS) positional errors while moving under the forest
canopy and to clarify the effects of polyline simplification on area and perimeter estimations. We used the Pathfinder Pro
XR and GPSMAP 76S, which are categorized as “high-end mapping” and “general navigation” GPS receivers, respectively. The field
tests were conducted in both natural and plantation forests. The results showed that the Pathfinder Pro XR, which has better
multipath rejection technology, worked well, especially in the plantation forest under unfavorable conditions of higher stand
density. We used analysis of variance to clarify the effects of the receiver type, positioning mode, stand type, and polyline
simplification method on area and perimeter estimations. The receiver type and positioning mode were found to be significant
factors that affected area estimation. The Pathfinder Pro XR estimated the area more accurately than the GPSMAP 76S, and differential
GPS estimated the area more accurately than autonomous GPS. With respect to the perimeter, the receiver type, positioning
mode, and polyline simplification method were found to be significant factors. The results showed that perimeter estimation
was improved by using the velocity filter, and further improved by using the velocity filter and Douglas-Peucker algorithm,
especially when the Pathfinder Pro XR was used. The GPSMAP 76S estimated the perimeter accurately without any filtering because
its default speed filter worked well, even though the GPSMAP 76S is a general navigation GPS receiver. 相似文献
4.
Genetic diversity of Populus euphratica populations in northwestern China determined by RAPD DNA analysis 总被引:1,自引:0,他引:1
Five Populus euphratica Oliver populations in northwestern China were analyzed using RAPD DNA markers to determine genetic diversity among and within populations. One hundred-and-five polymorphic bands were observed, ranging in size from 250 bp to 1700 bp, using 10 primers. Only one population on the north side of the Tianshern Range had a unique band common to all individuals that was not found in individuals from populations in the Tarim River valley. Intra-population genetic diversity was high in two populations along the Tarim River and low in the other three populations. There was no significant correlation between genetic distances and geographic distances. The result of correspondence analysis shows that the individuals from the three populations with low genetic diversity are isolated from each other. The result of cluster analysis based on genetic distance shows that the population in the Tianshern Range is genetically distant from the other populations. These results suggest that the Tianshern Range population was genetically isolated from the other populations. 相似文献
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Yaser Hosny Elewa Mohammad Hafez Bareedy Ahmed Awad Abu Al Atta Osamu Ichii Saori Otsuka Tomonori Kanazawa Shin-Hyo Lee Yoshiharu Hashimoto Yasuhiro Kon 《Veterinary research communications》2010,34(6):557-567
Previously, the distribution of myoepithelial cells (mecs) in the salivary glands was studied by both immunohistochemistry,
and transmission electron microscopy; however, little was elucidated concerning their morphological features, especially in
goats. This study was performed to investigate the correlation between the cytoarchitecture of the mecs in goat major salivary
glands (parotid, mandibular, and sublingual glands) and the nature of the saliva secretion. The cytoarchitectural features
of the mecs were examined by scanning and transmission electron microscopy as well as immunohistochemically. The secretory
endpieces in the parotid gland are of the pure serous type, but in both the mandibular and sublingual glands they are of the
mixed type. In all studied glands, the intercalated ducts were covered by mecs which, unlike the large stellate cells that
surrounded the secretory endpieces, were spindle-shaped with few cytoplasmic processes. Interestingly, the mecs were found
to bulge on the basal surfaces of the serous acini and intercalated ducts in all glands and to be in close contact to the
seromucous tubules surface in the mandibular and sublingual glands forming a continuous network around it. In conclusion,
the differences in the degree of development of the mecs as well as the number of their cytoplasmic processes may be correlated
with the nature of the secretion and the number of the secretory granules. Thus these observations may have some relevance
in the diagnosis of atrophy and pathogenic conditions of these glands. 相似文献