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101.
The induction of haploid plants from F1 hybrids between CMS shallot with Allium galanthum cytoplasm and common onion was examined. Starting with 535 unpollinated flowers cultured in B5 medium 25 seedlings from part henogenetic embryos were obtained of which 13 seedlings survived. Eleven seedlings were determined as haploid plants (2n = x = 8) and 2 seedlings were doubled haploid plants (2n = 2x = 16). All haploid and doubled haploid plants preserved chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) from A. galanthum. Segregation in different characters was observed among the haploid plants. The haploid and doubled haploid plants exhibited the different combinations of genes from shallot and common onion. Crossing of the doubled haploid plants with other shallot strains, common onion cultivars or related species may produce excellent F1 hybrids for bulb production. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
102.
Phenolic constituents of a new functional fermented tea produced by tea-rolling processing of a mixture (9:1) of tea leaves and loquat leaves were examined in detail. The similarity of the phenolic composition to that of black tea was indicated by high-performance liquid chromatography comparison with other tea products. Twenty-five compounds, including three new catechin oxidation products, were isolated, and the structures of the new compounds were determined to be (2R)-2-hydroxy-3-(2,4,6-trihydroxyphenyl)-1-(3,4,5-trihydroxyphenyl)-1-propanone 2-O-gallate, dehydrotheasinensin H, and acetonyl theacitrin A by spectroscopic methods. In addition, theacitrinin A and theasinensin H were obtained for the first time from commercial tea products. Isolation of these new and known compounds confirms that reactions previously demonstrated by in vitro model experiments actually occur when fresh tea leaves are mechanically distorted and bruised during the production process.  相似文献   
103.
Oxidation of low-density lipoprotein (LDL) has been implicated in atherogenesis. Antioxidants that prevent LDL from oxidizing may reduce atherosclerosis. This study investigated LDL antioxidant activity in edible plant products for development of dietary supplementation to prevent atherosclerosis. Fifty-two kinds of edible plants were extracted using 70% aqueous ethanol solution, and the antioxidant activity of the extracts, which inhibit human LDL oxidation induced by copper ion, was determined on the basis of the oxidation lag time and represented as epigallocatechin 3-gallate equivalent. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and total phenolic content were also measured for comparisons with antioxidant activity in LDL. Plant products showing the greatest activity in LDL oxidation assay were akamegashiwa (Mallotus japonicus) leaf, Japanese privet (Ligustrum japonicum) leaf, green tea [Camellia sinensis (L.) O. Kuntze], and astringent persimmon (Diospyros kaki). The present study revealed high levels of LDL antioxidant activity in plant products for which such activity levels are underestimated in the DPPH radical scavenging assay and Folin-Ciocalteu assay.  相似文献   
104.
Introduction

Phosphorus applied on a phosphate deficient soil, by increasing the root development of the plant, or by stimulating the soil microflora especially in the rhizosphere, may increase the amount of phosphorus which the plant takes up from the soil. This present paper is a report on a pot culture investigation of such an effect of added phosphorus.  相似文献   
105.
A digital image correlation (DIC) method was applied to measure strain which arose and remained beneath the finished surface in slow-speed orthogonal cutting of hinoki (Chamaecyparis obtusa), to evaluate the damage in the subsurface cell layers. While the quarter-sawn surface was cut parallel to the grain, the side surface, flat-sawn surface, was captured by a high-speed camera. The images were analyzed to calculate strain in a region of 0.67 × 0.22 mm allocated beneath the finished surface. Almost no strain normal to the cutting direction was detected for the depth of cut and cutting angles, 0.05 mm and smaller than 60°, respectively. For the depths of cut and cutting angles, larger than 0.1 mm and smaller than 60°, respectively, the fore-split induced tensile strain normal to the cutting direction, although it hardly remained after the cutting. The compression strain normal to the cutting direction clearly remained for the cutting angles larger than 70°, regardless of the depths of cut employed in this study. The subsurface damage assumed from the residual strain distribution corresponded to the appearance of the subsurface layer in the X-ray computed tomography (CT) images. It was also revealed, and the DIC program could not always measure excessively large strain correctly.  相似文献   
106.
107.
Laccases play important roles in the development of fruiting bodies and in lignin degradation by basidiomycetes. In this study, we present novel phenotypes of transgenic tobacco plants with a chimeric gene for fungal laccase under the control of the cauliflower mosaic virus 35S promoter. At the flowering stage, the transgenic plants that produced recombinant laccase had brownish anthers instead of the greenish anthers of wild-type plants. The brownish anthers exhibited male sterility with a nondehiscent phenotype at varying frequencies. The frequency of nondehiscence depended on the temperature at which plants were cultivated and it was higher at 24°C than at 29°C. The cell wall structures of transgenic anther tissues were almost the same as in the wild type, but the stomium was severely deformed, and abnormal components were apparent in cells of the endothecium and epidermis. Furthermore, the pattern of deposition of flavonoids in the transgenic anther epidermis differed from the wild-type pattern. The expression of laccase also induced other phenotypic changes in the flowers of transgenic plants, namely, increased petal number, fused and petaloid stamens, and doubling of floral organs. These results indicate that the ectopic expression of laccase influences various aspects of flower development.  相似文献   
108.
Acetic acid fermentability of various compounds from beech wood as produced in a two-step hot-compressed water treatment was evaluated by fermentation tests using standard compounds with Clostridium thermoaceticum and Clostridium thermocellum. For cellulose- and hemicellulose-derived products, the former microorganism was found to ferment compounds with low molecular weights such as monosaccharides, decomposed products, and organic acids to acetic acid, while the latter was found to ferment compounds with high molecular weights such as polysaccharides and oligosaccharides to acetic acid. Lignin-derived products were, on the other hand, fermented by both microorganisms to acetic acid. Based on these lines of evidence, co-culture with C. thermoaceticum and C. thermocellum was evaluated and proven to increase acetic acid fermentability. Consequently, almost all compounds produced from beech wood in hot-compressed water were found to be converted to acetic acid when using these microorganisms in combination. Thus, hot-compressed water treatment coupled with acetic acid fermentation would likely be a powerful method to produce acetic acid from lignocellulosics.  相似文献   
109.
Penetration rates of laser pulses transmitted from a small-footprint airborne light detection and ranging (LiDAR) system in closed-canopy, middle-aged (40–50 years old) hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.) and sugi (Cryptomeria japonica D. Don) plantations that had similar levels of canopy openness were studied. The number of transmitted pulses was 107 427 points/ha for the hinoki cypress stand and 122 883 points/ha for the sugi stand. The penetration rates of the first (Pf) and second pulses (Ps) that reached the ground were 0.1% and 1.0% in the hinoki cypress stand, and 2.6% and 5.5% in the sugi stand, respectively. Penetration rates for the total number of pulses (Pf+s) that reached the ground within each stand were 1.1% and 8.1%, respectively, and values for Pf+s, Pf, and Ps for sugi and hinoki cypress stands were significantly different (P < 0.001). The results of this study indicated that the generation of accurate digital terrain models in dense hinoki cypress stands with complex topographies using only the data from laser pulses with poor laser penetration rates is likely to be difficult.  相似文献   
110.
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