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1.
Compost has been proposed as a means of simultaneously diverting organic materials from landfills while producing a valuable product that improves tilth, organic matter content and nutrient supply of agricultural soils. Composts manufactured from different source materials may have markedly different properties however, even if they meet all regulatory requirements. We compared the capacity of composts made from three different combinations of organic wastes (horse manure and bedding, mink farm wastes, municipal solid waste (MSW) and sewage sludge) along with clarifier solids from a chemo-thermomechanical pulp mill, to enhance the growth of tomato (Lycopersicon esculentum L.) seedlings grown in nutrient-poor organic potting soil. Germination and seedling emergence of tomatoes, cress (Lapidium sativum L.) or radish (Raphanus sativus L.) were tested to assess phytotoxicity of the four amendments. Mink farm compost and horse manure compost stimulated root and shoot growth of tomato seedlings but MSW compost and pulp mill solids were strongly inhibitory. MSW compost and unamended potting soil also inhibited seedling emergence and pulp mill solids produced stunting and deformities in radish and cress seedlings. Both toxic constituents and nutrient imbalances may be responsible for the growth-inhibiting effects of these amendments. Application of pulp mill solids to agricultural soil without composting may lead to deleterious effects on vegetable crops.  相似文献   

2.
An enzyme which actively transaminates L-cystathionine, L-cystine, L-lanthionine and S-aminoethyl-L-cysteine has been purified from bovine kidney. The transaminase appears to be pure up to 90% and probably consists of two subunits of similar molecular mass of about 47 kDa. The enzymatic products arising from the transamination of L-cystathionine and related compounds spontaneously cyclize into ketiminic structures, which are the immediate precursors of unusual imino acids recovered in biological materials. The specificity towards other amino acid and oxo acid acceptors is similar to the specificity exhibited by rat kidney glutamine transaminase. This suggests that the sulfur amino acid transaminations that have been described could be performed by the bovine kidney glutamine transaminase.  相似文献   

3.
The cotyledons, leaves and inflorescences of the radish, Raphanus sativus, have been examined for their content of hydroxylated cinnamic acid malate esters. 2-O-(p-coumaroyl)-l-malate, 2-O-caffeoyl-l-malate and 2-O-feruloyl-l-malate were found to be quantitatively predominating compounds in the fraction of carboxylic acids isolated from radish leaves and inflorescences. Identifications were based on PC, TLC, HVE, GC, HPLC, UV and NMR spectroscopy. The l- or (2S)-configuration of malic acid released by hydrolysis from the esters was determined by using l-malate dehydrogenase. A combined column chromatography technique applied prior to HVE, HPLC and GC was useful for separating the malate esters from most other low MW plant constituents. The significance of the present investigation is briefly discussed in relation to the metabolism of phenolic constituents of glucosinolate-containing plants, and the effects of these compounds in relation to insect feeding behaviour.  相似文献   

4.
病毒病是危害萝卜作物的主要病害之一,芜菁花叶病毒(TuMV)作为萝卜病毒病的主要毒源,给萝卜生产造成严重经济损失。由于缺乏精准鉴定,萝卜育种中缺乏稳定可靠的抗TuMV材料。本研究就国家蔬菜种质资源中期库提供的来自中国25个省份125个县市和其他3个国家的150份代表性萝卜种质资源对TuMV的抗性进行了苗期鉴定和ELISA检测,筛选出23份抗病材料,其中1份表现免疫。这些材料对萝卜抗病毒病基因定位和新品种培育具有重要意义。  相似文献   

5.
Calcium sulfoaluminate‐based cements (CSA) are proposed as a cement alternative with a low carbon footprint. The nature of CSA makes the manufacturing process to require lower temperature, less fuel, and less calcite. However, it requires aluminum oxide, Al2O3, which would be originated from bauxite and bauxite‐derived wastes, and sulfur, coming from calcium sulfate or elemental sulfur. An eco‐efficiency assessment of CSA cements, benchmarked against the conventional Portland cement, has been performed following the principles of ISO 14045 on eco‐efficiency for a total of 240 CSA clinker production scenarios. The eco‐efficiency indicator relates an environmental indicator with a product system value indicator, and it is calculated for each of the studied parameters: bauxite geographical origin, the fuel used for clinkering, the source of sulfur, and the composition of the clinker. Eco‐efficiency results show a strong dependence on the origin of bauxite, while other parameters, as the fuel used, its content in sulfur, or the supply of other raw materials, are of less importance. The most eco‐efficient solutions are those with certain closeness to bauxite sources. To achieve global solutions, that is, cement‐making based on CSA independently of the origin of the raw materials, the amount of bauxite needs to be minimized and CSA composition restricted.  相似文献   

6.
Bio-oxidation has proved to be a viable process for the oxidative pretreatment of refractory gold-bearing sulfides. Generally, the oxidation rate is maximal at 20% solids for high sulfide content materials [ca. 30% sulfur]. Low grade ores [1% sulfur] have been successfully oxidized at 55% solids, indicating a link between the sulfide grade of the material and the optimal solids concentration for operation. Concentrations of high solids have been reported to lower oxidation rates, increase lag times, and decrease the ultimate extent of oxidation. This review discusses the various factors that have been proposed as causes of these phenomena. The factors include oxygen and carbon dioxide availability, low bacteria-solids ratio; mechanical damage or inhibition of the bacteria, inhibition of bacterial attachment, and the buildup of toxic leach products or other detrimental substances such as some flotation reagents. (c) 1993 John Wiley & Sons, Inc.  相似文献   

7.
The evolutionary processes that take place in invasive plant populations are not well documented or understood. Interspecific hybridization between cultivated radish (Raphanus sativus) and R. raphanistrum is known to be responsible for the origin of the invasive California wild radish, but little is known about the nature of the hybridization events that produced the hybrid-derived lineage. We analyzed the trnL-rpl32 intergenic region of chloroplast DNA (cpDNA) obtained from 37 cultivated radish individuals from four different cultivars, 53 R. raphanistrum individuals from six European populations and 104 California wild radish individuals from 11 populations covering its entire range throughout the state. We found that cultivated radish and R. raphanistrum shared no cpDNA haplotypes but that they both shared haplotypes with California wild radish, evidence for bidirectional hybridization between the progenitor species in the creation of the California lineage. We also found evidence that multiple cultivars and multiple European source populations contributed to the diversity of cpDNA haplotypes within California. Studies like this will continue to be important for our understanding of the origin of invasive populations and the mechanisms by which they succeed.  相似文献   

8.
对40份初选萝卜种质分别接种Xcc8004和XccBJ两个菌株,进行黑腐病苗期抗性鉴定,对其中8份代表性萝卜种质肉质根切片接种Xcc8004进行抗性鉴定和27份萝卜种质幼苗接种8个效应物基因进行过敏反应鉴定。结果表明:不同萝卜种质苗期对黑腐病的抗性存在显著差异,筛选出高抗Xcc8004的材料3份、抗病1份、中抗4份,高抗XccBJ的材料1份、抗病2份、中抗5份。萝卜苗期对Xcc8004和XccBJ的抗病性极显著相关,幼苗和肉质根对Xcc8004的抗病性极显著相关。筛选出17份对不同效应物表现过敏反应的萝卜种质。对效应物XC0241表现过敏反应的种质数最多,对XC0542和XC0541表现过敏反应的种质数次之。不同抗源对不同效应物的过敏反应程度有所不同。稳定可靠抗病资源的获得为萝卜抗病育种和抗病机理的深入研究提供了基础材料。  相似文献   

9.
为了揭示不同产地土壤因子对关黄柏酚酸类、生物碱类和柠檬苦素类化学成分含量的影响,本研究对31个样点的15个土壤因子及所产药材的10种化学成分含量进行检测。通过冗余分析考察土壤因子与化学成分间的相关性,用t-value双序图解读各土壤因子对各化学成分含量的影响,并通过聚类分析考察样点土壤特征对药材化学特征的影响。结果显示:土壤中的盐分、速效磷、阳离子交换量、速效氮、速效钾、有机质、有效锰、硫和有效铜对关黄柏化学成分含量有显著影响;3-O-阿魏酰奎尼酸、4-O-阿魏酰奎尼酸、5种生物碱、黄柏内酯含量随上述土壤因子含量的上升呈下降趋势;紫丁香酚苷和黄柏酮主要呈上升趋势。研究结果表明环境土壤因子的差异会导致关黄柏多种化学成分的含量发生显著性改变。  相似文献   

10.
The essential oil of aerial parts of Ruta graveolens was obtained by hydrodistillation with a 0.74% yield on a dry weight basis. Thirty-eight components were identified by GC and GC-MS analyses. 2-Ketones predominated in the essential oil, with undecan-2-one (46.8%) and nonan-2-one (18.8%) as the main constituents. The essential oil and some of its constituents were tested for their allelopathic activity in vitro on radish germination and radicle growth in light and darkness. The essential oil and some of its minor constituents were effective and dose-dependent inhibitors of both the germination and radicle growth; 2-ketones are not active. The possible allelopathic activity of rue essential oil and some its isolated constituents is reported.  相似文献   

11.
To investigate the gene function of radish (Raphanus sativus L.), several attempts have been made to generate genetically transformed radish. However, no efficient and relatively simple method for the genetic transformation of radish has been developed to date. In this study, we established an Agrobacterium-mediated genetic transformation method using the hypocotyl-derived explants of radish cultivar “Pirabikku”. Primarily based on the Brassica transformation procedure, we optimized it for radish transformation. Using this system, the transformation efficiency of radish hypocotyl explants by Agrobacterium tumefaciens strain GV3101 harboring pIG121-Hm was 13.3%. The copy number of transfer DNA integrated into the genome was either one or two in the four independent transgenic plants. Two of the four plants exhibited male sterility and did not produce self-pollinated seeds. Examination of the expression of the β-glucuronidase (GUS) gene in T1 plants from fertile T0 plants showed that the GUS genes were inherited. The improvement in the genetic transformation in this study might pave the way for accelerated molecular breeding and genetic analysis of radish.  相似文献   

12.
SNP markers for QTL analysis of 4-MTB-GSL contents in radish roots were developed by determining nucleotide sequences of bulked PCR products using a next-generation sequencer. DNA fragments were amplified from two radish lines by multiplex PCR with six primer pairs, and those amplified by 2,880 primer pairs were mixed and sequenced. By assembling sequence data, 1,953 SNPs in 750 DNA fragments, 437 of which have been previously mapped in a linkage map, were identified. A linkage map of nine linkage groups was constructed with 188 markers, and five QTLs were detected in two F2 populations, three of them accounting for more than 50% of the total phenotypic variance being repeatedly detected. In the identified QTL regions, nine SNP markers were newly produced. By synteny analysis of the QTLs regions with Arabidopsis thaliana and Brassica rapa genome sequences, three candidate genes were selected, i.e., RsMAM3 for production of aliphatic glucosinolates linked to GSL-QTL-4, RsIPMDH1 for leucine biosynthesis showing strong co-expression with glucosinolate biosynthesis genes linked to GSL-QTL-2, and RsBCAT4 for branched-chain amino acid aminotransferase linked to GSL-QTL-1. Nucleotide sequences and expression of these genes suggested their possible function in 4MTB-GSL biosynthesis in radish roots.  相似文献   

13.
Sulfur is a chemically and biologically active element. Sulfur compounds in animal tissues can be present in two forms, namely stable and labile forms. Compounds such as methionine, cysteine, taurine and sulfuric acid are stable sulfur compounds. On the other hand, acid-labile sulfur and sulfane sulfur compounds are labile sulfur compounds. The sulfur atoms of labile sulfur compounds are liberated as inorganic sulfide by acid treatment or reduction. Therefore, the determination of sulfide is the basis for the determination of labile sulfur. Determination of sulfide has been performed by various methods, including spectrophotometry after derivatization, ion chromatography, high-performance liquid chromatography after derivatization, gas chromatography, and potentiometry with a sulfide ion-specific electrode. These methods were originally developed for the determination of sulfide in air and water samples and were then applied to biological samples. The metabolic origin of labile sulfur in animal tissues is cysteine. The pathways of cysteine metabolism leading to the formation of sulfane sulfur are discussed. Finally, reports on the physiological roles and pathological considerations of labile sulfur are reviewed.  相似文献   

14.
Microbial community biofabrics in a geothermal mine adit   总被引:1,自引:0,他引:1  
Speleothems such as stalactites and stalagmites are usually considered to be mineralogical in composition and origin; however, microorganisms have been implicated in the development of some speleothems. We have identified and characterized the biological and mineralogical composition of mat-like biofabrics in two novel kinds of speleothems from a 50 degrees C geothermal mine adit near Glenwood Springs, CO. One type of structure consists of 2- to 3-cm-long, 3- to 4-mm-wide, leather-like, hollow, soda straw stalactites. Light and electron microscopy indicated that the stalactites are composed of a mineralized biofabric with several cell morphotypes in a laminated form, with gypsum and sulfur as the dominant mineral components. A small-subunit rRNA gene phylogenetic community analysis along the stalactite length yielded a diverse gradient of organisms, with a relatively simple suite of main constituents: Thermus spp., crenarchaeotes, Chloroflexi, and Gammaproteobacteria. PCR analysis also detected putative crenarchaeal ammonia monooxygenase subunit A (amoA) genes in this community, the majority related to sequences from other geothermal systems. The second type of speleothem, dumpling-like rafts floating on a 50 degrees C pool on the floor of the adit, showed a mat-like fabric of evidently living organisms on the outside of the dumpling, with a multimineral, amorphous, gypsum-based internal composition. These two novel types of biofabrics are examples of the complex roles that microbes can play in mineralization, weathering, and deposition processes in karst environments.  相似文献   

15.
M Raynal  D Depigny  F Grellet  M Delseny 《Gene》1991,99(1):77-86
Three cDNA clones, encoding napin storage proteins from radish, were isolated and sequenced. They fall into two classes differing in the size of the primary translation product. Sequences of the two classes are very well conserved and they display an organization very similar to that of the homologous genes from rapeseed and Arabidopsis which have previously been described. On the basis of hybridization intensity and the number of restriction fragments, we estimate that the radish napin multigene family is represented by eight to twelve members. The use of probes specific to each subfamily demonstrates that they contribute to a similar extent to the production of napin mRNA. Analysis of the sequence data suggests that the napin ancestral genes are probably derived from successive duplication and divergence of a protogene. Comparing other available napin sequences with those of radish reveals intriguing features. Comparison of the coding sequences shows that the homology between the radish and rapeseed sequences is much higher than that between each of the four members of the Arabidopsis gene family. This would suggest that the duplications which gave rise to the different members occurred independently in the two groups of species after separation of Arabidopsis from the Brassica lineage. However, similar comparison carried out on the 3' -noncoding sequences does not support this hypothesis, but shows that slightly different duplicated genes probably already existed in the common ancestor to the three genera. This paradox can be resolved by assuming that, within each genus, coding sequences for napin-encoding genes have been considerably homogenized as a result of concerted evolution.  相似文献   

16.
A putative sulfate transporter gene, RSultr3.2A, was identified from radish (Raphanus sativus L.). The RSultr3.2A gene encodes a polypeptide of 651 amino acids with a calculated molecular mass of 71701 Da. The deduced amino acid sequence preserves the common motifs of the sulfate transporters and exhibits a high degree of homology to other plant sulfate transporters. RSultr3.2A was not induced by sulfur starvation and was expressed in roots, stems, leaves, flowers and young pods, suggesting a possible need for the nonregulated and constitutive sulfate transport system of the plant. The RSultr3.2A is a single copy gene in the radish genome. A genomic sequence information corresponding to RSultr3.2A cDNA was found by PCR and sequencing. Comparison of cDNA and genomic sequences revealed that the coding sequence of RSultr3.2A consisted of 12 exons. In addition, another cDNA (RSultr3.2B) from radish young pods was found. As compared with RSultr3.2A, RSultr3.2B encodes a 499 amino acid protein with modifications in the carboxy-terminus. Sequence analysis suggested an occasional donor splicing site mutation (GT to TT) in the RSultr3.2A gene from radish young pods leading to the truncated cDNA RSultr3.2B.  相似文献   

17.
A neutral growth inhibitor, for which the name raphanusanin is proposed, has been isolated in crystalline form from light-exposed Sakurajima radish (Raphanus sativus var. hortensis f. gigantissimus Makino) seedlings and identified as a new compound, 3-methoxy-4-methylthio-2-piperithione by spectrometric analyses.

Applied raphanusanin inhibited the hypocotyl growth of etiolated radish and lettuce seedlings at concentrations higher than 1.5 × 10−6 molar.

The endogenous raphanusanin contents in cotyledons and hypocotyls of radish seedlings increased more under red light, but decreased or maintained the initial level in the dark. Its content in roots showed almost no change between the light and dark materials.

  相似文献   

18.
The volatile constituents of the Dufour gland in Myrmica rubra have been examined by gas chromatography-mass spectrometry. The principal constituents are 8-heptadecene, n-pentadecane, n-heptadecane, and 9-nona-dencene. The other constituents comprise mainly other alkanes, alkenes, and a few sesquiterpenes. The sting gland does not contain volatile materials.  相似文献   

19.
20.
Radish populations selected from the cvs Asmer Tip Top and Sparkler on the basis of high or low preference by the cabbage root fly for egg laying were tested at different ages by exposing them to the pest in a laboratory test chamber. Results confirmed the existence of a cycle of changing attractiveness of radish for egg laying, the peak occurring as plants reached a marketable age. Selection within radish cvs for different levels of preference resulted in a shift in the cycle of attraction such that ‘high-preference’ plants reached a peak in attractiveness earlier than ‘low-preference’ ones. Egg laying was correlated with the total amounts of two volatile glucosinolate hydrolysis products (4–methylthio-3–butenyl isothiocyanate and 1–cyano-4–methyl-thio-3–butene) detected in ether extracts of macerated radishes. The relationship between chemicals and egg laying suggested a possible chemical assay to complement biological techniques for identifying cabbage root fly-resistant radish for breeding work.  相似文献   

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