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491.
Improved nitrogen status enhances zinc and iron concentrations both in the whole grain and the endosperm fraction of wheat 总被引:6,自引:0,他引:6
This study was conducted to assess the role of increasing N supply in enrichment of whole grain and grain fractions, particularly the endosperm, with Zn and Fe in wheat. The endosperm is the most widely consumed part of wheat grain in many countries. Plants were grown in the greenhouse with different soil applications of N and Zn and with or without foliar Zn spray. Whole grain and grain fractions were analyzed for N, P, Zn and Fe. Increased N supply significantly enhanced the Zn and Fe concentrations in all grain fractions. In the case of high Zn supply, increasing N application enhanced the whole grain Zn concentration by up to 50% and the endosperm Zn by over 80%. Depending on foliar Zn supply, high N elevated the endosperm Fe concentration up to 100%. High N also generally decreased the P/Zn and P/Fe molar ratios in whole grain and endosperm. The results demonstrate that improved N nutrition, especially when combined with foliar Zn treatment, is effective in increasing Zn and Fe of the whole grain and particularly the endosperm fraction, at least in the greenhouse, and might be a promising strategy for tackling micronutrient deficiencies in countries where white flour is extensively consumed. 相似文献
492.
493.
Five disinfectants, Venno FF super, Venno Vet 1 super, Venno Oxygen, M&Enno-Veterin?r B neu und Neopredisan 135-1, were tested to evaluate their efficacy against caliciviruses at 20 and 10 degrees C. As model test virus served feline calicivirus type F9 (FCV F9). All disinfectants were tested according to Guidelines of the German Veterinary Association (DVG). The investigations were performed in suspension tests and germ carrier tests. The suspension tests were carried out without and with protein load. As protein was used foetal calf serum at the concentration of 40%. Venno FF super showed less protein dependence, however a considerable temperature dependence. This matter can be corrected by increase of concentration on 2%. Venno Vet 1 super was without protein especially effective. The losses on the effectiveness through low temperature and protein load can be annulled also here by increase of concentration. Venno Oxygen was more effective in the comparison to that here named both preparations. The effects of temperature can be corrected by extension of reaction time. The most effective preparation was M&Enno Veterin?r B neu. The disinfection occurred at 20 degrees C with 0.5% solution within 120 min and at 10 degrees C with 1.0% solution within 60 min. The fifth disinfectant Neopredisan was in suspension tests without protein load and carrier tests with gauze at 20 and 10 degrees C relative convincing but in germ carrier tests with poplar wood, no complete disinfection could be achieved within tested concentrations and reaction times. 相似文献
494.
Effect of Boll Age and Harvesting Period on Fiber Properties of Egyptian and Upland Cotton Cultivars
The physical properties of cotton fibers for the successive age of development were studied in three different periods. Three cultivars of Egyptian and Upland cottons; Giza 75, McNair 220 and Tamcot H. 37 , were planted at Fayoum Experiment Farm, Faculty of Agriculture in 1984 season. Fiber properties were studied on samples obtained from five successive stages of boll development in three different periods. Data obtained revealed that fibers from both Egyptian and Upland cultivars showed substantial increment in micronaire reading up to 42 days after flowering. Micronaire reading showed a trend similar to fiber maturity percentage in studied cultivars.
Within each period, fibers tended to be stronger, more extensible, tougher and have higher stiffness with the increase in boll age. The rate of increment in the successive boll ages for fiber strength and elongation characters were markedly higher in the Egyptian cultivar than the American upland cultivars, especially in the younger boll ages. Fiber length was slightly affected by the environment growth conditions. However, the increase in fiber length was progressive from the age of 21 days up to the age of 35 days. 相似文献
Within each period, fibers tended to be stronger, more extensible, tougher and have higher stiffness with the increase in boll age. The rate of increment in the successive boll ages for fiber strength and elongation characters were markedly higher in the Egyptian cultivar than the American upland cultivars, especially in the younger boll ages. Fiber length was slightly affected by the environment growth conditions. However, the increase in fiber length was progressive from the age of 21 days up to the age of 35 days. 相似文献
495.
‘Marsh’ (Citrus paradisi Macf.) grapefruit trees on rough lemon (C. jambhiri Lush.) rootstock received irrigated and unirrigated treatments. Half of each irrigation treatment received a GA3 + 2,4-D spray at color break. Pre-harvest sprays of GA3 and 2,4-D extended the grapefruit harvest season by increasing fruit removal and rind puncture force, delaying development of mature color and decreasing late-season and post-freeze fruit-drop. Although soil moisture content in the top 0.9 m of unirrigated blocks was reduced by approximately 40%, xylem pressure potentials of these trees and performance of GA3 + 2,4-D were unaffected. Soil moisture content was not an accurate indicator of tree water status for large grapefruit trees. 相似文献
496.
M. A. Shalaby M. A. El-Sisi O. E. Ismail A. I. Afaleque 《Veterinary research communications》1985,9(1):239-244
A virus was isolated from the brains of pigeons suffering from nervous disorders in different localities of the Eastern Province, Kingdom of Saudi Arabia. The new isolate caused a high morbidity, ranging from 33% to 50%, and a mortality rate which reached 40%.The virus produced pinpoint greyish pock lesions on the chorioallantoic membrane of embryonated hens' eggs and induced syncytial formation followed by rounding and lysis of the cells in chicken embryo fibroblast cultures. Virus infectivity was significantly reduced following treatment by 20% ether or chloroform. The isolated virus was identified as pigeon herpes encephalomyelitis virus by serum-neutralization, agar gel diffusion and fluorescent antibody staining techniques. 相似文献
497.
Root uptake of lipophilic zinc-rhamnolipid complexes 总被引:1,自引:0,他引:1
Stacey SP McLaughlin MJ Cakmak I Hettiarachchi GM Scheckel KG Karkkainen M 《Journal of agricultural and food chemistry》2008,56(6):2112-2117
This study investigated the formation and plant uptake of lipophilic metal-rhamnolipid complexes. Monorhamnosyl and dirhamnosyl rhamnolipids formed lipophilic complexes with copper (Cu), manganese (Mn), and zinc (Zn). Rhamnolipids significantly increased Zn absorption by Brassica napus var. Pinnacle roots in (65)Zn-spiked ice-cold solutions, compared with ZnSO4 alone. Therefore, rhamnolipid appeared to facilitate Zn absorption via a nonmetabolically mediated pathway. Synchrotron XRF and XAS showed that Zn was present in roots as Zn-phytate-like compounds when roots were treated with Zn-free solutions, ZnSO4, or Zn-EDTA. With rhamnolipid application, Zn was predominantly found in roots as the Zn-rhamnolipid complex. When applied to a calcareous soil, rhamnolipids increased dry matter production and Zn concentrations in durum (Triticum durum L. cv. Balcali-2000) and bread wheat (Triticum aestivum L. cv. BDME-10) shoots. Rhamnolipids either increased total plant uptake of Zn from the soil or increased Zn translocation by reducing the prevalence of insoluble Zn-phytate-like compounds in roots. 相似文献
498.
Effects of long-term organic and mineral fertilizers on bulk density and penetration resistance in semi-arid Mediterranean soil conditions 总被引:4,自引:0,他引:4
Soil aggregation is of great importance in agriculture due to its positive effect on soil physical properties, plant growth and the environment. A long-term (1996-2008) field experiment was performed to investigate the role of mycorrhizal inoculation and organic fertilizers on some of soil properties of Mediterranean soils (Typic Xerofluvent, Menzilat clay-loam soil). We applied a rotation with winter wheat (Triticum aestivum L.) and maize (Zea mays L.) as a second crop during the periods of 1996 and 2008. The study consisted of five experimental treatments; control, mineral fertilizer (300-60-150 kg N-P-K ha−1), manure at 25 t ha−1, compost at 25 t ha−1 and mycorrhiza-inoculated compost at 10 t ha−1 with three replicates. The highest organic matter content both at 0-15 cm and 15-30 cm soil depths were obtained with manure application, whereas mineral fertilizer application had no effect on organic matter accumulation. Manure, compost and mycorrhizal inoculation + compost application had 69%, 32% and 24% higher organic matter contents at 0-30 cm depth as compared to the control application. Organic applications had varying and important effects on aggregation indexes of soils. The greatest mean weight diameters (MWD) at 15-30 cm depth were obtained with manure, mycorrhiza-inoculated compost and compost applications, respectively. The decline in organic matter content of soils in control plots lead disintegration of aggregates demonstrated on significantly lower MWD values. The compost application resulted in occurring the lowest bulk densities at 0-15 and 15-30 cm soil depths, whereas the highest bulk density values were obtained with mineral fertilizer application. Measurements obtained in 2008 indicated that manure and compost applications did not cause any further increase in MWD at manure and compost receiving plots indicated reaching a steady state. However, compost with mycorrhizae application continued to significant increase (P < 0.05) in MWD values of soils. Organic applications significantly lowered the soil bulk density and penetration resistance. The lowest penetration resistance (PR) at 0-50 cm soil depth was obtained with mycorrhizal inoculated compost, and the highest PR was with control and mineral fertilizer applications. The results clearly revealed that mycorrhiza application along with organic fertilizers resulted in decreased bulk density and penetration resistance associated with an increase in organic matter and greater aggregate stability, indicated an improvement in soil structure. 相似文献
499.
Chemical chaperones reduce ER stress and restore glucose homeostasis in a mouse model of type 2 diabetes 总被引:1,自引:0,他引:1
Ozcan U Yilmaz E Ozcan L Furuhashi M Vaillancourt E Smith RO Görgün CZ Hotamisligil GS 《Science (New York, N.Y.)》2006,313(5790):1137-1140
Endoplasmic reticulum (ER) stress is a key link between obesity, insulin resistance, and type 2 diabetes. Here, we provide evidence that this mechanistic link can be exploited for therapeutic purposes with orally active chemical chaperones. 4-Phenyl butyric acid and taurine-conjugated ursodeoxycholic acid alleviated ER stress in cells and whole animals. Treatment of obese and diabetic mice with these compounds resulted in normalization of hyperglycemia, restoration of systemic insulin sensitivity, resolution of fatty liver disease, and enhancement of insulin action in liver, muscle, and adipose tissues. Our results demonstrate that chemical chaperones enhance the adaptive capacity of the ER and act as potent antidiabetic modalities with potential application in the treatment of type 2 diabetes. 相似文献
500.
A number of factors persist to constrain the non-timber forest products (NTFPs) market and, by extension, its potential to contribute meaningfully to livelihood development and poverty reduction objectives. To better utilise the potential of NTFPs, it is important to have a better understanding of the key factors governing the success and failure of NTFPs trade. This paper reports on the market constraints and socio-economic factors that influence trade in five top-priority NTFPs within the tropical lowland rainforests of south-west Nigeria. The NTFPs investigated were bush mango (Irvingia gabonensis), African walnut (Plukenetia conophora), chew-stick (Massularia acuminata), fever bark (Annickia chlorantha) and bush pepper (Piper guineense). Field data were collected in 10 villages located within and around Omo and Shasha forest reserves using a household questionnaire survey. The results showed that seasonality, poor transport, lack of storage facilities and market information were the four main constraints influencing marketing and trade in the NTFPs. In addition, the level of education, gender (sex), household income, ethnicity, distance to the market and access to roads significantly influenced market knowledge and information among households involved in the trade of NTFPs. There is need to improve on the limited source of NTFPs information, enhance skills for product transformation, build innovative storage facilities, and develop the process of domestication and integration in traditional land-use systems. 相似文献