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851.
Sivakumaran S Meagher LP Foo LY Lane GA Fraser K Rumball W 《Journal of agricultural and food chemistry》2004,52(6):1581-1585
The chemical characteristics of the purified procyanidin polymers of the flowers of the forage legume red clover (Trifolium pratense L.) were studied by (13)C NMR, acid-catalyzed degradation with benzyl mercaptan, and electrospray ionization mass spectrometry (ESI-MS). The (13)C NMR showed that the fraction consisted of predominantly procyanidin polymers. The thiolysis reaction products indicated a mean degree of polymerization (mDP) of 9.3 with epicatechin (81%) as the abundant flavan-3-ol extension unit and the terminating units dominated by catechin (95%). ESI-MS showed a range of oligomeric procyanidin ions (DP of 2-11). The white clover floral prodelphinidins consist of terminal units with nearly equal proportions of epigallocatechin (52%) and gallocatechin (48%) and extender units showing epigallocatechin (56%) and gallocatechin (39%). The dramatic difference in the stereochemistry of the terminal and extender units observed for the red clover floral procyanidins contrasts with the mixture of cis and trans stereochemistry observed for white clover floral prodelphinidins. 相似文献
852.
Christian Zrb Berenike Stracke Birgit Tramnitz Dominique Denter Ali Sümer Karl Hermann Mühling Feng Yan Sven Schubert 《植物养料与土壤学杂志》2005,168(4):550-557
In the first phase of salt stress, growth of plants is impaired mainly by osmotic stress. To elucidate the effect of NaCl salinity on elongation growth of maize leaves in the first phase of salt stress, we investigated the effect of NaCl on gene expression and activity of the plasmalemma H+ ATPase of elongating leaves of maize (Zea mays L.). Treatment of maize plants with 125 mM NaCl for 3 d decreased leaf growth relative to control plants (1 mM NaCl). Whereas H+ ATPase hydrolytic activity was unaffected, the ability of the H+ ATPase to establish a pH gradient was strongly reduced. Total mRNA of plasmalemma H+ ATPase was slightly increased. However, mRNA of the ATPase isoform MHA1 was significantly reduced and ATPase isoform MHA4 was strongly increased at the mRNA level. Synthesis of total H+ ATPase protein was unchanged as revealed by western blot. The results indicate that reduced pumping of H+ ATPase in leaf plasmalemma under salt stress may be caused by a switch to gene expression of the specific isoform MHA4, which shows inferior H+‐pumping efficiency in comparison to isoforms expressed under control conditions. We propose that reduced H+ pumping of plasmalemma H+ ATPase is involved in the reduction of leaf growth of maize during the first phase of salt stress. 相似文献
853.
Summary A further collecting mission was carried out in the Democratic People's Republic of Korea in 1987 within the frame of the agreement between the Academies of Sciences of the DPRK and the German Democratic Republic. 73 samples of medicinal plants, grain legumes, oil- and fibre plants and cereals were collected. The material collected is promising for research and breeding purposes.
Bericht über eine Reise zur Sammlung pflanzlicher genetischer Ressourcen in der Koreanischen Demokratischen Volksrepublik im Jahre 1987
Zusammenfassung Eine weitere Sammelreise in der Koreanischen Demokratischen Volksrepublik wurde im Jahre 1987 im Rahmen des Abkommens zwischen den Akademien der Wissenschaften der KDVR und der Deutschen Demokratischen Republik durchgeführt. 73 Proben von Arzneipflanzen, Körnerleguminosen, Öl- und Faserpflanzen sowie Getreiden wurden gesammelt. Das Sammelmaterial ist als aussichtsreich für Forschungs- und Züchtungsaufgaben einzuschätzen.
- 1987
- . 73 , , . .相似文献
854.
Zusammenfassung Im Juni 1986 wurde im Irak eine Sammelreise durchgeführt. Landsorten von Getreide, Gemüsen und einigen anderen Kulturpflanzen konnten gesammelt werden; insgesamt 141 Proben. Die Generosion ist bei den Getreiden schon weit fortgeschritten. Durch die Einführung vieler neuer Gemüsesorten muß in den nächsten Jahren mit einem empfindlichen Verlust von Gemüse-Landsorten gerechnet werden. Das Sammelmaterial ist von großer Bedeutung für die Züchtungsforschung und Züchtung.
Collection of land-races of cultivated plants in Iraq, 1986
Summary A collecting mission was carried out in Iraq in June 1986. Land-races of cereals, vegetables and some other crops could be collected, altogether 141 accessions. Genetic erosion is advanced in cereals. Because of the introduction of many new cultivars a severe loss of vegetable land-races has to be expected in the next years. The material collected is important for breeding research and breeding purposes.
1986
1986 , , . 141 . ¶rt;. - , , , . , .相似文献
855.
856.
Soil quality deterioration and consequent reduced productivity characterize the Vertisols in the highlands of Ethiopia. The problem is exacerbated by lack of appropriate land preparation alternatives for the major crops in the area. A field experiment was carried out for 6 years (1998–2003) at Caffee Doonsa in the central highlands of Ethiopia to evaluate alternative land preparation methods on the performance of wheat (Triticum durum Desf.), lentil (Lens culinaries Medik L) and tef (Eragrostis tef L) grown in rotation. Four methods of land preparation (broad bed and furrow, green manure, ridge and furrow and reduced tillage) were arranged in a randomized complete block design with three replications on permanent plots of 22 m by 6 m. Broad bed and furrow significantly increased the grain yield of lentils by 59% (from 1029 to 1632 kg ha−1) as compared to the control. On the other hand, reduced tillage resulted in the highest grain yield of wheat (1862 kg ha−1) and tef (1378 kg ha−1) as compared to 1698 kg ha−1 of wheat and 1274 kg ha−1 of tef for the control although the increase was not statistically significant. A gross margin analysis showed that BBF is the most profitable option for lentil with 65% increase in total gross margin. On the other hand, RT resulted in 11 and 8% increase in gross margin of wheat and tef, respectively as compared to the control. Based on the agronomic and economic performances best combinations of crop and land preparation method were: lentil sown on broad bed and furrow, and wheat and tef sown after reduced tillage. 相似文献
857.
Jayaprakasam B Vareed SK Olson LK Nair MG 《Journal of agricultural and food chemistry》2005,53(1):28-31
Anthocyanins are responsible for a variety of bright colors including red, blue, and purple in fruits, vegetables, and flowers and are consumed as dietary polyphenols. Anthocyanin-containing fruits are implicated in a decrease in coronary heart disease and are used in antidiabetic preparations. In the present study, we have determined the ability of anthocyanins, cyanidin-3-glucoside (1), delphinidin-3-glucoside (2), cyanidin-3-galactoside (3), and pelargonidin-3-galactoside (4), and anthocyanidins, cyanidin (5), delphinidin (6), pelargonidin (7), malvidin (8), and petunidin (9), to stimulate insulin secretion from rodent pancreatic beta-cells (INS-1 832/13) in vitro. The compounds were tested in the presence of 4 and 10 mM glucose concentrations. Our results indicated that 1 and 2 were the most effective insulin secretagogues among the anthocyanins and anthocyanidins tested at 4 and 10 mM glucose concentrations. Pelargonidin-3-galactoside is one of the major anthocyanins, and its aglycone, pelargonidin, caused a 1.4-fold increase in insulin secretion at 4 mM glucose concentration. The rest of the anthocyanins and anthocyanidins tested in our assay had only marginal effects on insulin at 4 and 10 mM glucose concentrations. 相似文献
858.
Adel?UsmanEmail author Yakov?Kuzyakov Karl?StahrEmail author 《Journal of Soils and Sediments》2005,5(4):245-252
Background Aims, and Scope. Reducing heavy metal solubility and bioavailability in contaminated area without removing them from the
soil is one of the common practices in decreasing the negative impacts on the environment and improving the soil quality.
Therefore, our aim was to study the effect of clay minerals: Na-bentonite, Ca-bentonite, and zeolite applied to a contaminated
soil on immobilization of heavy metals, as well as on some soil parameters related with microbial activity.
Methods A soil derived from sewage sludge was incubated with clay minerals of either Na-bentonite, Ca-bentonite, or zeolite for 111
days (d). During the incubation experiment, concentrations of water soluble Zn, Cd, Cu, and Ni were measured after extraction
of 2 g air-dry soil with 50 ml of H2O for 2 h. After the water extraction, the soil sediment was extracted with 50 ml of 1
M NH4NO3 for 2 h to estimate the exchangeable amounts of heavy metals. Furthermore, soil microbial respiration, microbial
biomass C, Corg mineralization, metabolic quotient (qCO2), and inorganic N were also investigated.
Results and Discussion Water extractable and exchangeable forms of heavy metals were changed by incubation and addition of clay minerals. Incubation
of soil without addition of clay minerals (control) increased water extractable Cu by 12, 24 and 3.8% of initial content after
21, 62, and 111 d of incubation, respectively. The water extractable Zn decreased by 9% during 62 d of incubation and it tended
to increase by 14% at the end of the incubation, as compared with the initial soil. Water extractable Cd decreased by 71,
66 and 33% of initial content, and Ni decreased by 54, 70, and 58%, after 21, 62, and 111 d of incubation, respectively. During
the incubation experiment, the exchangeable form of all tested metals was decreased by incubation. The addition of clay minerals
led to a significant decrease in water soluble and exchangeable forms of heavy metals during the incubation experiment, resulting
in low metal extractability. The reduction in metal extractability was greater due to the addition of Na-bentonite or Ca-bentonite
than that due to the addition of zeolite. During the first 3 weeks after addition of clay minerals, the studied biological
parameters were not affected. However, as incubation progressed, the addition of Na- or Ca- bentonite led to a significant
increase in soil respiration, microbial biomass C, Corg mineralization, and inorganic N; and a significant decrease in qCO2.
This result is explained by sorption of heavy metals on Na-bentonite and Ca-bentonite and strong reduction of their toxicity.
Conclusions Our results clearly show that the addition of clay minerals, especially of Na-bentonite and Ca-bentonite, decreased the extractability
of four metals during incubation. The decreased metal extractability was accompanied by an increase of soil respiration, Corg
mineralization, microbial biomass C, and inorganic N and a decrease of metabolic quotient (qCO2), showing positive effect
of clay mineral addition on soil biological parameters.
Recommendations and Outlook The use of Na-bentonite and Ca-bentonite is promising tool for reduction the extractability and possible toxicity of heavy
metals in sewage sludge-contaminated soil. Therefore, the soils polluted with heavy metals may be ameliorated by addition
of clay minerals, especially Na-bentonite and Ca-bentonite. 相似文献
859.
Karl W.J. Williard David R. Dewalle Pamela J. Edwards 《Water, air, and soil pollution》2005,160(1-4):55-76
Although the large variations in nitrate export from forested watersheds have been attributed to a variety of natural and disturbance-related factors, baseflow nitrate concentrations in 49 mid-Appalachian forested watersheds were most strongly related to differences in bedrock geology. Within the mid-Appalachian region of Pennsylvania, Maryland and West Virginia, watersheds dominated by Pottsville and Allegheny sandstone (PVA), Catskill, Chemung, and Pocono shale and sandstone (CCP), and Mauch Chunk shale and Greenbrier limestone (MCG), respectively, exhibited significantly different low, intermediate, and high mean stream nitrate concentrations. Soil pH, soil percent N concentration (%N), soil C:N mass ratio, soil exchangeable Ca, watershed slope, and the occurrence of white ash (Fraxinus americana L.), sugar maple (Acer saccharum Marsh.), and eastern hemlock (Tsuga canadensis L.) were related significantly to bedrock geology type as well as stream nitrate levels. Other factors such as past land disturbances (fire and agriculture) and stand age (old-growth) typically were associated with only one bedrock geology type. However, within a bedrock geology type, past agriculture and the presence of old-growth forest may be important in explaining stream nitrate concentrations on an individual watershed basis. The basal area of black locust (Robinia pseudoacacia L.), a species that enhances soil nitrogen levels via nitrogen fixation, showed a moderate positive correlation with stream nitrate concentrations. Bedrock geology explained the most variation in winter (49%) and summer (32%) stream nitrate concentrations. Bedrock geology may have been a better predictor of stream nitrate concentrations than soil chemistry, because the geologic variation was better assessed at the regional scale of this study compared to soil chemistry, which varies at the micro-scale due to topographic, vegetation, microbial, and climatic influences. Results of this study suggest that bedrock geology is an important factor to consider when assessing forest nitrogen dynamics at a broad landscape scale. 相似文献
860.
Dr. Jürgen Schultze-Motel Dr. Reinhard Fritsch Dr. Karl Hammer Dr. Peter Hanelt Dr. Joachim Kruse Dr. Helga I. Maass Dr. Harald Ohle Klaus Pistrick 《Genetic Resources and Crop Evolution》1981,29(2):465-483
Summary Important papers on taxonomy and evolution of cultivated plants published in 1979 and 1980 were put together and briefly discussed.
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1979/1980
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1979 und 1980 wurden zusammengestellt und kurz kommentiert.
: 1979–1980
, 1979–1980 . .相似文献