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1.
3年生白桦同时接受3种外源糖溶液(蔗糖、果糖、葡萄糖)和3种高浓度CO2(700、1400、2100μL·μL-1CO2)处理.处理1个月后,测定了叶片的总糖、蔗糖、果糖和蛋白质含量.结果表明:在700μL·L-1和1400μL·L-1 CO2下,外源糖溶液增加了叶片的可溶性糖和蛋白质含量,其中外源蔗糖的效果最好:外源糖溶液与2100μL·L-1CO2结合,会抑制叶片积累总糖和蛋白质:在700μL·L-1和1400μL·L-1CO2下,喷施葡萄糖、果糖的叶片在蛋白质含量上没有明显差别:同700、1400μL·L-1CO2相比,除喷施果糖植株外,2100μL·L-1 CO2明显增加了叶片的总糖、蔗糖、果糖和蛋白质含量:在喷施同种外源糖溶液的情况下,叶片的糖含量与CO2浓度呈正相关性.图6参7.  相似文献   

2.
The amount and composition of sugar units comprising polysaccharides in sapwood and heartwood, or stemwood, of 11 industrially important pulpwood species were analysed. The polysaccharide content was between 60 and 80% (w/w) for all species, with cellulose as the predominant polysaccharide type and glucuronoxylans as the main non-cellulosic polysaccharides. The second most abundant non-cellulosic polysaccharides were either pectins, i.e. polygalacturonic acids, or glucomannans. The amount of acidic sugar units were 15–23% of the total amount of non-cellulosic sugar units in all samples, with the Acacia species in the high end. The amount and composition of water-soluble carbohydrates from ground wood samples were also analysed, since these are important in mechanical and chemimechanical pulping, and as a possible source of bioactive polymers. Sapwood released more carbohydrates than heartwood for most species. It is to be noted that the relative amount of dissolved acidic sugar units was larger from the heartwood than from the sapwood for all species. Probably due to the mild treatment conditions, the main dissolved polysaccharides were xylans only for a few samples, while easily soluble galactans, arabinogalactans, or mannans dominated in most species. Pectins dominated in heartwood of Populus grandidentata. Generally, pectins and acidic xylans were the main acidic polysaccharides.  相似文献   

3.
黄牡丹花粉生活力测定方法的比较研究   总被引：5，自引：1，他引：4       下载免费PDF全文
以黄牡丹的新鲜花粉为试材,利用单因子试验比较了液体培养基中蔗糖浓度、硼、钙、镁、钾对黄牡丹花粉萌发的影响,在此基础上进行了正交试验,比较了蔗糖、H3BO3及CaCl2对黄牡丹花粉萌发的影响;通过对醋酸洋红染色法、I-KI染色法和TTC染色法的比较,寻找快速测定黄牡丹花粉生活力的方法。试验结果表明:蔗糖及H3BO3对黄牡丹花粉萌发有极显著影响。在pH值为6.0时,蔗糖150 g·L-1+H3BO330 mg·L-1+CaCl220 mg·L-1适宜黄牡丹花粉培养,萌发率为68.7%;纯水培养没有造成花粉原生质体破裂,内含物外流,但萌发率极低,仅为3%;200 g·L-1以上的高浓度蔗糖溶液和300 mg·L-1以上的高浓度盐溶液会造成原生质体失水萎缩,质壁分离,这两种情况都抑制花粉萌发;TTC染色法测得的花粉活力率为64.9%,是快速测定黄牡丹花粉生活力的最适染色法。  相似文献   

4.
A polysaccharide, a glucan with mean Mr of 1.0×106 (MP1), was isolated from the mesocarp of fruits of Orbignya phalerata. Chemical and spectroscopic studies indicated that MP1 has a highly branched glucan type structure composed of α-(1→4) linked -glucopyranose residues with (3→4), (4→6), and with (3→6) branching points. MP1 enhanced phagocytosis in vivo and exhibited anti-inflammatory activity.  相似文献   

5.
杨树次生壁纤维素合酶的表达与互作模式分析   总被引：1，自引：0，他引：1       下载免费PDF全文
[目的]纤维素的合成在木材形成过程中具有重要的作用,纤维素合酶(Cellulose Synthase,CESA)是参与纤维素合成的关键酶。由于3种CESA形成一个有功能的纤维素合酶复合体,而杨树中包含CESA4、CESA7A、CESA7B、CESA8A和CESA8B5种次生壁CESA,本文从这5种CESA的表达模式与互作分析入手,探讨了其在次生壁纤维素合成中的工作模式。[方法]利用RNA-seq与基因芯片数据进行基因表达分析,揭示5种次生壁CESA在根、茎、叶组织的表达模式与次生维管再生过程中的表达变化。利用启动子驱动的GUS转基因材料GUS染色分析与实时定量PCR揭示5种次生壁CESA在各个组织的表达模式与在激素处理下的响应模式。利用荧光素酶互补实验揭示CESA7A、CESA7B、CESA8A与CESA8B之间的互作模式。[结果]基因表达分析表明,杨树5种次生壁CESA基因在杨树成熟茎中高表达,尤其在次生维管组织发育的后期高表达,表明其主要参与木材次生壁纤维素的合成。对启动子驱动的GUS转基因材料观察表明,CESA4、CESA7B、CESA8A和CESA8B的GUS信号在杨树茎和叶中较强,但这些次生壁CESA的表达模式存在一定的差异,这种差异在叶脉中表现地尤为明显。此外,在赤霉素GA3和细胞分裂素6-BA处理下,杨树次生壁CESA的表达量显著上调;在生长素NAA、油菜素内酯BR和乙烯处理下,杨树次生壁CESA的表达量下调,但不同的CESA对激素响应的表达量变化幅度存在差异。荧光素酶互补实验表明,杨树次生壁CESA7B和CESA8B、CESA7B和CESA8A、CESA7A与CESA8B之间存在互作,说明它们之间可以形成复合体。[结论]这些数据显示杨树5种次生壁CESA基因在不同组织与不同激素处理下的表达变化存在一定的差异,而它们之间均能互作,提示杨树5个次生壁CESA基因虽然具有同等的能力形成功能性的纤维素合酶复合体,但在不同组织、不同激素作用下可能有不同的组合方式,进而会导致木材成分的差异。  相似文献   

6.
Cratylia argentea, a drought tolerant shrub, is known to produce significant amounts of fodder during the dry season but little is known of its nutritive value for feeding animals. Two studies of quality and intake of Cratylia argentea, as an arboreal protein supplement for crossbred dual purpose cattle grazing Hyparrenhia rufa in the dry season, were carried out in San Miguel de Barranca, Puntarenas, Costa Rica (January–May). The first experiment was a 2 × 2 factorial arrangement of two forms of C. argentea foliage presentation: 1) fresh or wilted; and 2) sprayed or not with sugarcane molasses diluted in water. Wilting did not affect crude protein content and in vitro dry matter digestibility (IVDMD) but treating fresh C. argentea with molasses increased IVDMD by from 55.6 to 60.8% (P < 0.01). Intake of fresh C. argentea increased by 32% with wilting and by 43% with molasses treatment. Pooling data across treatments, a quadratic relationship between dry matter intake of H. rufa (y) and the amount of N consumed in C. argentea (x) was found (y = 1.25 + 0.095x – 0.001x 2). In the second experiment, milk production from the following treatments was evaluated: 1) chicken litter and molasses (D1); 2) chicken litter, sugar cane and wheat bran (D2); and 3) C. argentea, sugar cane and wheat bran (D3). Milk yields averaged 6.0 kg cow–1 day–1 and there were no significant differences between treatments. Milk fat was lower for D2 (2.7%), which had a higher amount of sugar cane in the diet, but differences were not significant. On the other hand, non-fat solids and lactose concentration of milk was higher (P < 0.05) for D2. Wilting or molasses treatment were effective management strategies for increasing dry matter intake of C. argentea. A higher dry matter intake of C. argentea was associated with increased intake of the fibrous H. rufa grass. Diets with C. argentea as the main protein source gave similar milk production levels and quality to those with chicken litter.  相似文献   

7.
Summary Microscopic and electron microscopic examination of the resin canal complex isolated from slash pine chlorite holocellulose showed it to be composed of thin-walled, unlignified tissue apparently without secondary thickening. The mature structure consisted of a central canal surrounded by three cellular layers. Epithelium forms the inner layer while the middle and outer layers consist of short (intermediate) and elongated (outer) parenchyma cells, respectively. In contrast to previous concepts, the middle lamella of these tissues is a complex structure which contains intercellular membranes and cellulosic and noncellulosic (probably galacturonan) intercell wall fibrils. Intercellular membranes encapsulate two or more cells and consist of one or more intact ancestral walls The number and total thickness of ancestral walls in the mature middle lamella vary with the number of cell divisions and the location of the cell plates within a fusiform cambium daughter cell. The development of the canal complex and of the ray tissue associated with it can be traced by studying the cell wall ultrastructure.Symbols used in Figures A Canal complex axis - Ar Artifact - C Cytoplasmic remnant - CS Canal complex surface - D Canal - E Epithelial cells - F Intercell-wall fibrils - I Intermediate cells - L Cell lumen - M Intercellular membrane - M 1 Intercellular membrane - M 2 Intercellular membrane - M 3 Intercellular membrane - ML Middle lamella - O Outer cell - P Primary cell wall - PL Part of an ancestral wall partially pulled from the canal complex surface - T Thin-walled portion of an epithelial cell - x Cleavage within middle lamella - y Cleavage along middle lamella-primary wall boundary The authors thank Drs. I. H. Isenberg and L. L. Winton, members of the thesis advisory committee, for their assistance in the conduct of the research, Miss Olga Smith for assistance in electron microscopy and for drawing Figs. 1, 5, and 7, and J. D. Hankey for assistance in photomicroscopy.  相似文献   

8.
The storage modulus and the mechanical loss tangent of untreated, extracted, and sugar- impregnated canes (Arundo donax L.) were measured over a temperature range of –150° to 0°C at low frequencies. Two relaxation processes, labeled and , were detected in the ranges –60° to 0°C and –120° to –100°C, respectively. The and processes shifted to lower temperatures with increasing moisture content. The process was detected only in the canes containing sugar. The magnitude of its loss peak increased with an increase in sugar content. It was speculated that the process was due to some interactive molecular motions of the adsorbed water and sugar. The process, detected in all of the canes, was attributed to the motion of the adsorbed water in the amorphous cell wall substances.  相似文献   

9.
Xylan prepared from culms of kumaizasa (Sasa senanensis Rehd.), a representative species of bamboo grass, was hydrolyzed with-xylanase ofStreptomyces olivaceoviridis E-86. Four arabinoxylo-oligosaccharides and two glucuronoxylo-oligosaccharides were isolated from the enzymatic hydrolysate of the xylan by chromatography on a charcoal column, a Dowex 1-x8 column, a Toyo-pearl HW-40S column, and a LiChrospher 100 NH2 column and on preparative paper chromatography. The results of the structural analyses of the saccharides showed that the isolated oligosaccharides had the structures of 32--l-arabinofuranosyl-xylobiose, 32--l-arabinofuranosyl-xylotriose, 32--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylobiose, 33--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylotriose, 23--4-O-methyl-d-glucuronosyl-xylotriose, and 23--d-glucuronosyl-xylotriose. From the structural analysis of the oligosaccharides derived from the xylan, kumaizasa xylan was concluded to be a kind of arabinoglucuronoxylan having not only stubs of singlel-arabinose and singled-glucuronic acid but also stubs of disaccharide units such as-d-xylopyranosyl-(1 2)-l-arabinofuranose.  相似文献   

10.
Phenylboronic acid (PBA) was tested in terms of boron leachability from treated wood. In addition, the fungal and termiticidal efficacy of PBA-impregnated sugi (Cryptomeria japonica D. Don) wood was tested against the decay fungi Coriolus versicolor (L. ex Fr.) Quel. and Tyromyces palustris (Berk. et Curt) Murr., representing white-rot and brown-rot fungi, respectively, and the Formosan subterranean termite Coptotermes formosanus Shiraki. Ion chromatography analysis of hot water extracts of treated wood before and after leaching indicated that PBA is considerably resistant to water leaching, and saturation of the treatment solution increased the fixation ratio of boron in wood, whereas boric acid could not remain in wood impregnated even with the saturated solution. Decay test results revealed the excellent bioactive performance of PBA. Wood treated with 0.34% PBA solution was found resistant to both decay fungi, even after running-water leaching for 10 days and treatment with 1.00% PBA completely inactivated the Formosan subterranean termite for the leached specimens. Weight gain levels were 0.18% w/w (0.46kg/m3) and 0.99% w/w (2.49kg/m3) for these concentration levels, respectively, after being leached by running water. Contrary to the general belief that boron is a slow-acting toxicant against termites and unable to prevent mass loss of treated wood, PBA acted rapidly, and the mass loss caused by termites was low.This study was presented in part at the 47th annual meeting of the Japan Wood Research Society, Kochi, April, 1997  相似文献   

11.
A new withanolide identified by spectroscopic analysis as 12β-acetoxy-4-deoxy-5,6-deoxy-Δ5–withanolide D and Withanolide D, were isolated from the leaves of Acnistus arborescens. Cytotoxic activity of these two compounds against human tumor cell lines HT-29, MCF-7, MKN-45, HEp-2, HeLa, U-937 and two human normal fibroblast cultures, Fib04 and Fib05, were assessed. Withanolide D presented in vitro cytotoxic activity against tumor cell lines at the low micromolar range (LC50:1.0 to 1.69 µM) and showed a slightly lower activity against Fib04, suggesting moderated selectivity among tumoral and normal cells. No cytotoxic effect was observed for 12β-acetoxy-4-deoxy-5,6-deoxy-Δ5–withanolide D.  相似文献   

12.
Previous research has shown that carbon isotope signatures (Δ13C) may correlate well with water status in 1–2 years old, plantation grown Eucalyptus globulus. Here we investigate this relationship for mid-rotation aged (5 years) trees and whether a simple field determination of phloem sugar concentrations is a reliable surrogate for Δ13C. We sampled six plantations covering much of the climatic range of E. globulus plantations in Australia (average annual rainfall 618–1094 mm). We found significant correlations between phloem Δ13C and phloem sugar concentrations across and within plantations. Both parameters were also correlated with a climate wetness index. We thus conclude that phloem sugar concentration is a useful surrogate for Δ13C and hence water status of mid-rotation E. globulus. We also observed strong correlations of phloem Δ13C and phloem sugar concentrations with growth across all plantations, providing some confirmation that water limits growth of E. globulus at a larger scale. This relationship was much weaker or absent within plantations, suggesting that factors other than water supply contribute significantly to growth limitations at smaller (within-plantation) scales.  相似文献   

13.
为探究配方施肥对云南松松针养分含量和土壤理化性质的影响,为云南松幼林抚育提供科学依据,以8年生云南松为试材,采用U*15(157)均匀设计开展复合肥、氮肥、磷肥、镁肥和硼肥配施的试验。处理组合的针叶长、烘干含水率、针叶全氮、全磷和全钾分别为23.90~27.34 cm、55.47%~60.88%、0.17%~0.57%、0.13%~0.33%和0.17%~0.82%,对照的则为24.14 cm、60.75%、0.35%、0.17%和0.29%。其中,全磷和全钾具有显著的差异。处理组合的土壤pH、烘干含水率、速效氮、速效磷、速效钾和胸径增长率分别为4.08~4.69、17.27%~34.59%、22.77~41.91、7.70~11.80、66.44~174.67 mg/kg和23.5%~50.3%,对照的则为4.42、17.27%、23.70、8.23、81.11 mg/kg和22.4%,处理组合间速效磷、速效钾和胸径增长率具有极显著的差异。土壤理化性质与因素具有复杂的相关性,硼肥与胸径增长率呈现显著的正相关;配施复合肥1.6 kg/3 cm、氮肥0.10 kg/3 cm、磷肥0.2 kg/3 cm,镁肥7.5 g/3 cm和硼肥1.5 g/3 cm可改善土壤理化性质,促进云南松幼树胸径生长。  相似文献   

14.
Summary 13C CP MAS NMR spectroscopy was used to characterize the structural changes of cell wall polymers in beech wood Fagus sylvatica during drying processes. The analysis of five wood samples, namely, untreated, untreated dried, pre-treated by steam and/or NaOH subjected to drying showed partial depolymerization of lignin component as well as the change of the ratio of the crystalline and of the amorphous parts of cellulose as the consequence of wood pre-treatment. In addition, T1ρ(1H) relaxation times were determined in beech wood sample pre-treated with steam at 135 °C and the lignin isolated from this sample. The magnitudes of the relaxation times were found comparable in both samples as well as in the lignin-cellulose model compound. These unique T1ρ (1H) values indicate that spin diffusion is complete and homogeneous due to spatial proximity of spins and confirmed the formation of lignin-cellulose complex during thermal treatment of wood. Received 30 June 1997  相似文献   

15.
Pinus sylvestriformis is an important species as an indicator of global climate changes in Changbai Mountain, China. The water use efficiency (WUE) of this species (11-year old) was studied on response to elevated CO2 concentration at 500±100 μL·L−1 by directly injecting CO2 into the canopy under natural condition in 1998–1999. The results showed that the elevated CO2 concentration reduced averagely stomatal opening, stomatal conductance and stomatal density to 78%, 80% and 87% respectively, as compared to normal ambient. The elevated CO2 reduced the transpiration and enhances the water use efficiency (WUE) of plant. The project was supported by Chinese Academy of Sciences Responsible editor: Chai Ruihai  相似文献   

16.
[目的]目前有关松材线虫与伴生细菌的关系及伴生细菌的病原作用是松树枯萎病研究的重点。为了揭示松材线虫与伴生细菌之间存在的密切关系,作者对松材线虫LIV幼虫携带的细菌进行了分离鉴定。[方法]根据培养性状和16S rDNA序列同源性以及系统发育学等方面进行分析鉴定。[结果]确定LIV幼虫携带的是香茅醇假单胞杆菌（Pseudomonas citronellolis）,携带率为100%;每条LIV幼虫携带量在1.4×105~4.5×105。LIV幼虫生活在松褐天牛体内,是引起松材线虫病侵染流行的唯一虫态;新发现的香茅醇假单胞杆菌能分解纤维素及降解或合成萜烯和酚类化合物。[结论]LIV幼虫携带香茅醇假单胞杆菌的发现,揭示了松树、松褐天牛、松材线虫、细菌同为一体的紧密关系,并为揭示松树枯萎病机制提供了一种新病原和重要的研究思路。  相似文献   

17.
Li S  Li J  Guan XL  Li J  Deng SP  Li LQ  Tang MT  Huang JG  Chen ZZ  Yang RY 《Fitoterapia》2011,82(7):1081-1085
The various fractions of the barks of Cyclocarya paliurus were systematically tested for hypoglycemic effects in alloxan-induced diabetic rats. The results showed that the chloroform fraction of the 75% EtOH extract of the barks of this plant exhibited significant blood sugar reducing activity, most of which were significantly higher than that of positive-drug metformin hydrochloride. A new compound, together with nine known compounds, was isolated from the most active fraction. The structure elucidation was based on spectroscopic methods, including two-dimensional NMR experiments (1H-1H COSY, HMQC, and HMBC). All of the isolates were evaluated for their α-glycosidase and glycogen phosphorylase inhibitory activities.  相似文献   

18.
The gastrointestinal activity of hydroalcoholic extract (HE) of Salvia officinalis was evaluated in a model of ethanol-induced gastric lesion. HE showed excellent activity, with ID50 84.0 (54.8–128.9) mg/kg. The acetic acid-induced ulcer and the total acidity of the gastric secretion were also reduced by HE, and, in vitro experiments, the H+,K+-ATPase activity was inhibited. Carnosol was identified as a possible active constituent for the gastroprotective effect of HE.  相似文献   

19.
Fibre morphology, anatomy and ultrastructure in cell wall of Salix gordejecii normal wood were examined by transmission electron microscopy (TEM). S. gordejecii tension wood can be recognized anatomically by the presence of gelatinous (G) fibres, which contain a conspicuously thickened inner cell wall layer. TEM images showed that cell wall of S. gordejecii normal wood was typically divided into three layers including the primary wall (P), the middle lamellar (ML) and the secondary wall (S1, S2 and S3). Lignin distribution was determined by using confocal laser scanning microscopy (CLSM) and transmission electron microscopy with energy dispersive X-ray analysis (TEM-EDXA). Confocal images (530 nm) of S. gordejecii normal wood showed strongly lignified CCML, and weakly lignified ML and S2 layer. Weakly lignified fibres (F) and strongly lignified vessels (V) were also detected by using CLSM. Results obtained from confocal microscopy were further confirmed by using TEM-EDXA, indicating that the ratio of lignin concentration in CCML, ML and S2 is 1.72 (1321):1.31 (1006):1 (768). Lignin distribution in tension wood is similar to that in normal wood, except for the non-lignified G layer.  相似文献   

20.
The potential of the entomopathogenic nematode Steinernema feltiae (Filipjev) (Rhabditida: Steinernematidae) Rioja strain was assessed under laboratory conditions. Last instar larvae of Leptinotarsa decemlineata Say (Coleptera: Chrysomelidae), Spodoptera littoralis Boisdouval (Lepidoptera: Noctuidae) and Trichoplusia ni Hübner (Lepidoptera: Noctuidae) were exposed to infective juveniles (IJs) under laboratory conditions. Larval mortality, days to larval death, infection cycle length, and reproductive potential were recorded. Efficacy was assessed performing dose–response experiments. The results indicate that control of L. decemlineata with S. feltiae Rioja strain is not economically profitable (LC50 = 99.61 IJs/cm2), whereas results obtained for T. ni (LC50 = 0.27 IJs/cm2) are promising. Due to the life cycle of this insect, the efficacy needs to be investigated in foliar application studies. The effects on S. littoralis (LC50 = 0.69 IJs/cm2) was considered the most suitable for development of the Rioja strain as a biocontrol agent for soil application.  相似文献   

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