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1.
Seasonal variation in pigmentation and anthocyanidin phenetics in commercial Eustoma flowers 总被引:2,自引:0,他引:2
A. F. M. Jamal Uddin Fumio Hashimoto Toshiki Miwa Katsuhiro Ohbo Yusuke Sakata 《Scientia Horticulturae》2004,100(1-4):103-115
The seasonal change in petal color and pigmentation of 29 commercial Eustoma cultivars was studied. The flowers are basically divided into four groups according to the major anthocyanidin phenotype in association with petal coloration, i.e., delphinidin (Dp)-based (purple flower), cyanidin (Cy)-based (reddish purple flower), pelargonidin (Pg)-based (pink flower), and none (white flower) groups. The constitution of petal anthocyanidins was not changed by forcing treatment in most of the flowers. Lightness (L*) and chroma (C*, color saturation) showed a change along with the increase/decrease of hue angle difference (ΔH*), thus simultaneously the chromatic tonalities tended to move to redder and bluer, respectively. Floral pigment clustering described two flower groups in a dendrogram, based on anthocyanidin constitutions as phenetic markers, which are apparently the Dp- and Pg-based phenotypes of anthocyanidin syntheses. The Cy-based flowers made a subcluster with the Pg-based flowers, indicating a close relationship in the biosynthesis of the two anthocyanidins, and suggesting the Dp- and Pg-syntheses complement one another. 相似文献
2.
We investigated the validity and efficiency of a survey using sight per unit effort (SPUE) of sika deer and shrub-layer decline
rank (SDR), which is an index of decline in the physical structure of a whole stand caused by sika deer, based on data collected
on a broad scale. This survey was to be used to manage a deer population in order to conserve a forest ecosystem. First, we
evaluated the spatial and temporal scales of deer density that are most appropriate for predicting decline in the status of
understory vegetation. The model with SPUE calculated in a buffer with a radius of 4.5 km using data for the past 4 years
was found to be the best. We showed that our knowledge of the relationship between deer density and status of shrub-layer
vegetation is improved by identifying the most suitable spatial and temporal scales of SPUE for predicting SDR. Next, we quantified
the effects of SPUE and environmental components on SDR in stands. We found that SPUE had the greatest effect on SDR among
all explanatory variables. Moreover, the area under the curve (AUC) was large in a model that only used SPUE (AUC = 0.718).
This result suggests that the variation in SDR among stands was explained well by SPUE regardless of differences in the forest
environment. Furthermore, we identified the effective values of SPUE for preventing shrub-layer vegetation from declining
through deer density control. We conclude that a management system based on SPUE and SDR is a simple and valid method for
managing deer populations in order to conserve forest ecosystems. 相似文献
3.
4.
The amounts of CO2 that are absorbed and emitted by forest in a model stand area were determined using two calculation methods, namely the flow
approach and the stock approach for emission trading, to understand the relationships between the cutting age for the highest
profit rate (CAHPR; optimum tree ages to be cut so as to maximize the profit) and (1) the prices of CO2 and (2) the balance between CO2 emission and absorption. The resultant CAHPR differed between these two CO2 accounting methods, which give different tree ages for maximum log volume yield. A rise in CO2 price caused the CAHPR to approach the tree age of maximum log volume in the flow approach method, and to deviate from the
tree age of maximum log volume in the stock approach method. Even at the same CO2 price, the CAHPR differed between the CO2 accounting methods. At low CO2 prices, the CAHPR did not affect situations where the difference of average profit is large by cutting age. On the other
hand, the CAHPR was greatly affected at low CO2 prices when the mean log volume growth changed with tree age. These trends were found to be universal.
Received: September 18, 2001 / Accepted: October 25, 2002
Acknowledgments This study is one of the fifth science study subsidy projects of the Japan Forest Technology Association.
Correspondence to:K. Sakata 相似文献
5.
Summary A light microscopic (LM) visual technique to determine the polyethylenimine (PEI) distribution in a wood-PEI composite was studied by the adsorption of acid red or the circulation of Cu(II) ion with PEI in the composite. The amount of the adsorbed dye or Cu(II) on the composite increased linearly with an increase in the PEI content of the wood-PEI. The dyed composites were observed with LM under monochromatic light, corresponding to their absorption maxima at 560 nm for acid red and at 640 nm for copper chelate. The microscopic image was photographically recorded and the negative was subjected to densitometric analysis. At a polymer content lower than 4% in the composite, about 70% of total polymer was located in the middle lamella region, leaving only 30% in the secondary wall. With increasing PEI content of the composite, the concentration in the secondary wall increased, and about 80% of the polymer was located in the secondary wall at a PEI content of 27%. There were no noticeable differences between the amount of polymer detected by dyeing with acid red and by chelating with Cu(II). From the results of the line analysis of the intensity of the characteristic X-ray of uranium, the distribution of the PEI in the cell wall agreed closely with that determined by the LM method. It was concluded that the LM visual technique to determine the PEI location in the wood-PEI composite by dyeing with acid red or by chelating with Cu(II) is a simple and reliable method. 相似文献
6.
The regeneration characteristics of Picea jezoensis Carr. and Abies sachalinensis Masters on cut stumps in natural forest under selection cutting and natural regeneration were studied in a sub-boreal forest of the Hokkaido Tokyo University Forest. The following points were investigated: (1) what decay class of cut stumps are suitable for regeneration of the two conifer species; (2) what part, either a root collar or a cut surface, of a cut stump is suitable for regeneration; and (3) what percentages of cut stumps support conifer seedlings. The percentages of cut stumps that supported conifer seedlings increased as the decay class advanced, but slightly decreased in the latest stage of decay class, V. Both P. jezoensis and A. sachalinensis seedling densities per cut stump and per square meter of cut stumps increased as the decay class advanced. Some root collars in decay class IV supported A. sachalinensis seedlings, but few supported P. jezoensis. Densities of P. jezoensis per cut surface and per square meter of cut surface in decay class IV were higher than those of A. sachalinensis. On the other hand, densities of A. sachalinensis per root collar and per square meter of root collar in decay class IV were higher than those of P. jezoensis. Cut stumps in advanced decay classes are more suitable for regeneration of P. jezoensis and A. sachalinensis than those in early decay classes. Whereas a cut surface is more suitable for regeneration of P. jezoensis, a root collar is more suitable for regeneration of A. sachalinensis. Cut stumps are not sufficient to ensure enough conifer regeneration because not all conifer cut stumps in advanced decay classes support conifer seedlings. 相似文献
7.
Kyotaro Noguchi Tadashi Sakata Takeo Mizoguchi Masamichi Takahashi 《Journal of Forest Research》2005,10(6):435-441
Fine roots are a key component of forested ecosystems, but available information is still limited. This study examined the
production and mortality of fine roots less than 1 mm in diameter in a Japanese cedar (Cryptomeria japonica D. Don) plantation located on the Kanto Plain in central Japan. We used a minirhizotron technique in combination with soil
coring, and collected data for 1 year (May 2002–May 2003). Fine root production and mortality were determined from changes
in the lengths of individual fine roots on minirhizotron tubes. Both fine root production and mortality rates were greater
in the upper soil than in lower soil levels. Both rates were seasonal, with higher values in summer than in winter; this trend
was more pronounced in upper soil levels. These results suggest that environmental conditions, such as temperature or soil
properties, affect the production and mortality rates of fine roots. Fine root production and mortality occurred simultaneously,
and their rates were similar, which may have led to unclear seasonal changes in fine root standing crop estimates. Soil coring
indicated that the fine root biomass of this stand was about 120 g m−2, of which 40% was from Japanese cedar. The estimated rates of dry matter production and mortality of total fine roots, including
understory plants, were both approximately 300 g m−2 year−1. 相似文献
8.
Tien‐Chun Wan Yu‐Tse Liu Lan‐Tyi Duann Kuo‐Hui Yu Chih‐Ming Chen Liang‐Chuan Lin Ryoichi Sakata 《Animal Science Journal》2014,85(1):75-80
The purposes of this study were to assess the improvement of fatty liver induced by ethanol with animal liver and bile extracts. This research aimed to increase the economic values of animal liver and bile extracts and used these to reduce damage of ethanol‐induced fatty liver. Extracts came from animal liver and bile, including pig bile powder, pig liver extract, a mixture of pig bile powder and pig liver extract, chicken bile powder, chicken liver extract, and a mixture of chicken bile powder and chicken liver extract, and these were fed to Long‐Evans rats. The results showed that rats fed ethanol for long terms could increase values of aspartate transaminase, cholesterol, γ‐glutamy‐transferase and alkaline phosphatase. Pig bile powder could decrease the values of aspartate transaminase, cholesterol and γ‐glutamy‐transferase. The significances also decreased on aspartate transaminase, γ‐glutamy‐transferase and aspartate transaminase, which were carried out with the pig liver extract treatment. These results suggest pig bile and liver extracts have high potential to improve rats' ethanol‐induced fatty liver with serum biochemical parameters. 相似文献
9.
Summary The potential of isozymes for distinguishing asparagus varieties was carried out by a survey on 21 varieties using 10 enzyme systems: GOT, SkDH, DIA, PGM, MDH, IDH, PGD, ACP, PGI, MR and ADH. Only 3 enzymes, SkDH, GOT and PGM, showed useful polymorphisms. The varieties were found heterogeneous according to their genetic structure: open pollinated varieties were more heterogeneous than clonal hybrids; the F1 hybrid and the vitroclones were homogeneous. As expected from the narrow genetic basis of the varieties, only a few alleles per isozyme locus were present. Moreover, for each enzyme, one allele or type was predominant so that the discriminating power of the method was low. However some of the varieties could be identified and different applications of the results are presented.Abbreviations D.U.S.-
Distinction-Uniformity-Stability
- ACO-
aconitase
- ACP-
acid phosphatase
- ADH-
alcohol dehydrogenase
- CAT-
catalase
- DIA-
diaphorase
- END-
endopeptidase
- GOT-
glutamate oxaloacetate transaminase
- IDH-
isocitrate dehydrogenase
- MDH-
malate dehydrogenase
- MR-
menadione reductase
- PGI-
phosphoglucoisomerase
- PGM-
phosphoglucomutase
- PGD-
phosphoglucose dehydrogenase
- POX-
peroxidase
- SkDH-
shikimate dehydrogenase 相似文献
10.
Three rhesus monkeys which had been isolated from social contact during their first year of life persistently overate and overdrank during adulthood. These monkeys ingested approximately twice as much fluid and food as the control animals reared normally. 相似文献