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41.
《Communications in Soil Science and Plant Analysis》2012,43(19-20):2839-2854
Abstract In this study, a strong association between cobalt (Co) and manganese (Mn) in different geochemical soil phases (fractions) was evaluated using a continuous‐flow sequential extraction technique employing a modified Tessier extraction scheme. With the flow system, detailed extraction profiles of Co and Mn in soils could be obtained by plotting concentrations of the elements extracted against extraction time (plots referred to as extractograms). Extractograms may be used as an indicator of whether the elements dissolving in the same extraction step are closely associated, or are merely extractable with the same reagent. From the soil samples studied, the coincidence of Co and Mn peaks seems to indicate a close association of these elements in the exchangeable, reducible, and oxidizable fractions. Analysis of flow extraction data suggested that the association between Co and Fe is not as strong as reported in previous studies based on the statistical analysis of batch fractionation data. 相似文献
42.
V. V. Agte M. K. Gokhale K. M. Paknikar S. A. Chiplonkar 《Plant foods for human nutrition (Dordrecht, Netherlands)》1995,48(2):149-158
Cereals including millets are consumed in India as a staple with wide variety of pulses and vegetables in varying proportions. Trace mineral contents of pearl millet are two to ten times higher than that of rice. Comparative performance of pearl millet based (PM) diets as against rice based (RB) diets in terms of trace mineral bioavailability was studied, based on the prevailing dietary patterns in India. In vitro percent dialysability of zinc, iron, copper and manganese under simulated gastrointestinal conditions was considered as indicator of metal bioavailability. Dialysable zinc and iron were estimated using 65 Zn and 59 Fe as tracers, while dialysable copper and manganese were measured by Atomic absorption spectrophotometer for 20 food items and 15 RB and 17 PM diets prepared from these items. Results indicated that percent dialysability of zinc and copper was higher for RB diets than PM diets, while that of iron and manganese were comparable. Total dialysable iron, copper and manganese in PM diet was 2 to 4 times higher than RB diet. 相似文献
43.
The Fe‐inefficient T203 and the Fe‐efficient A7 and Pioneer 1082 (P1082) soybeans (Glycine max (L.) Merr.) were grown hydroponically with no (0 mg Fe L‐1 ; ‐Fe) and a minute level (0.025 mg Fe L‐1 ; +Fe) of Fe to (a) compare their responses to Fe‐deficiency stress and (b) relate Fe‐efficiency in soybeans to their ability to initiate the Fe‐stress‐response mechanism at low levels of Fe. With no Fe in solution, P1082 released similar levels of H+ ions, but released less reductant from their roots and there was less reduction of Fe3+ to Fe2+ by their roots than by A7 roots. These responses were also one day later and occurred after a more severe chlorosis and a lower leaf Fe had developed in P1082 than in A7. With 0.025 mg L‐1 of solution Fe, it was not necessary for the Fe‐stress response mechanism to be fully activated to make Fe available in A7 soybean, whereas a strongly enhanced Fe stress response was observed in P1082. Increased Fe uptake and regreening of leaves immediately succeeded initiation of the Fe stress response in both cultivars and at both levels of Fe. Thus, P1082 was slightly less efficient than A7 soybean, but would be classed more efficient than the previously studied soybean cultivars A2, Hawkeye, Bragg, Pride, Anoka, and T203. These results support the hypothesis that the most efficient soybeans are those which can initiate the Fe‐stress response mechanism with little or no Fe in the growth medium. The near simultaneous occurrence of the factors in the Fe‐stress response mechanism (H ion and reductant release, reduction of Fe to Fe by roots), and the immediate increase in leaf Fe and chorophyll contents following that response suggest that all these factors act in concert, not independently, to aid in the absorption and transport of Fe to plant tops. 相似文献
44.
Economically valuable pistachio nut trees are extensively grown in the Southeastern part of Turkey. A great percentage of the total annual pistachio nut yield in Turkey is obtained from this region. However, fertility aspects of these pistachio trees have not been studied in detail. Thus, there is a need to determine the optimum fertilizer rates to increase the yield and quality of pistachio nuts. Fertilizer trials were conducted on an established 37 year‐old‐pistachio orchard. Inorganic nitrogen (N) and phosphorus (P) fertilizers were applied in three and two rates, respectively. Potassium (K) was added to all trees as a basal rate. In addition, selected trees received air‐dried sheep manure, and additional inorganic macro‐ and micro‐nutrients as a foliar application at three different times during the course of experiment. Fertilizer treatments influenced the fruit yield, productivity, fruit size, percentages of dehisced fruit shell, and nutmeat. Positive effects of these treatments on leaf element content, N, P, and K, were also obtained. Fruit protein and oil contents were not influenced by addition of organic and inorganic fertilizers. 相似文献
45.
土壤锰的研究现状及展望 总被引:5,自引:0,他引:5
就土壤锰含量、分布及其形态,锰有效性因素,锰毒及其矫正方法及与植物营养元素间的关系及其现状等方面进行综合论述。 相似文献
46.
The role of Tween 80 in biobleaching of unbleached hardwood kraft pulp (HWKP) with manganese peroxidase (MnP) was investigated. Among the surfactants (e.g., Tween 80, Tween 20, CHAPSO) the most significant brightness increase was obtained with Tween 80. Tween 80 and Tween 20 exhibited several effects, such as dispersion of degraded lignin and activation of MnP, that partly contributed to the brightening of HWKP during MnP treatment. However, these characteristics did not explain the most appreciable effect on the brightness increase by Tween 80. Lipid peroxidation of surfactants during MnP biobleaching was determined by measuring the peroxide value (POV). The order of the POV increase was consistent with that of the brightness increase of pulp during MnP treatment in the presence of various surfactants or linolenic acid. However, radicals and peroxides derived from lipid (linolenic acid) peroxidation by lipoxidase hardly brightened the HWKP by themselves. These results suggested that Tween 80 was peroxidized by Mn(III), and that Mn(III) and lipid peroxidation of Tween 80 synergistically brightened HWKP.This study was presented in part at the 43rd lignin symposium, Fuchu, Tokyo, Oct. 26–27, 1998 and the 49th annual meeting of the Japan Wood Research Society, Tokyo, April 2–4, 1999 相似文献
47.
48.
拉萨河谷冬春季放牧与舍饲彭波半细毛羊牧草、血液及被毛矿物质含量 总被引:1,自引:0,他引:1
为分析拉萨河谷冬春季放牧与舍饲彭波半细毛羊采食牧草、血液及被毛中主要矿物质元素的含量,试验选用1.5岁左右彭波半细毛羊母羊60只,随机分为放牧组(GZ)和舍饲组(IF)进行试验。结果表明:试验所用牧草矿物质元素,除钼外其他元素含量均为绿麦草>冬季天然牧草。冬季天然牧草磷、镁、硫、铜、锰、锌和硒及绿麦草镁含量低于正常范围。(2)舍饲组血清钙(P=0.026)、硫(P=0.030)、铜(P=0.011)和钼(P=0.014)含量高于放牧组,镁(P=0.090)、铁(P=0.071)、锌(P=0.083)和碘(P=0.066)含量有增高的趋势;其被毛钙(P=0.003)、磷(P=0.006)、镁(P<0.001)、铁(P=0.022)、锰(P<0.001)和碘(P=0.012)含量均高于后者,铜含量有增高的趋势(P=0.068)。在血液和被毛中,放牧组血清铜、锰及被毛铜、锰和硒含量及舍饲组血锰及被毛锰、硒含量均低于推荐值。以上结果表明,拉萨河谷冬春季放牧彭波半细毛羊钙、铁、钼和碘充足,但磷、镁、硫、铜、锰、锌和硒缺乏或不足;舍饲(以谷物为主的精补料+绿麦草干草)能有效解决磷、镁、硫、铜、锌和硒的缺乏问题,但锰仍需补充。 相似文献
49.
Arbuscular mycorrhizal fungi (AMF) have great potential for assisting metal-hyperaccumulating plants in the remediation of contaminated soils. However, little information is available about the symbiosis and community composition of AMF associated with manganese (Mn) hyperaccumulator, such as Phytolacca americana, growing on Mn-contaminated soils under natural conditions. Therefore, the objective of this study was to analyze AMF diversity and community composition in P. americana roots growing at an Mn mining site. Molecular techniques were used to analyze AMF community composition and phylogenetic relationship in P. americana roots sampled from three Mn mine spoils and one adjacent reference areas. Results obtained showed that mycorrhizal symbionts successfully established even in the most heavily Mn-polluted sites. Root colonization and AMF diversity were significantly negatively correlated with total and extractable Mn concentrations. Principal component analysis (PCA) revealed that Mn contamination impacted AMF diversity, and shaped AMF community structure. Phylogenetic analyses demonstrated that all species were affiliated with Glomus, suggesting that Glomus was the dominant genus in this AMF community. Some unique sequences that occurred exclusively in heavily polluted sites associated with P. americana may belong to symbiotic fungi with great potential for improving the phytoremediation efficiency of Mn-contaminated soils. 相似文献
50.
饲粮锰对蛋鸡组织锰含量及其生长发育和生产性能的影响 总被引:3,自引:0,他引:3
本试验研究了饲粮不同锰水平对蛋鸡组织器官中锰含量及其生长发育、产蛋性能和孵化效果的影响。结果表明:羽毛、消化道、肝脏、胫骨和肾脏中的锰量都随饲粮锰的提高而显著增加(P<0.01)。当雏鸡饲粮锰含量在13.5ppm时,锰在体内沉积出现负平衡,雏鸡脱腱症出现率为5.21%。产蛋鸡第1组(17.8ppm Mn)的产蛋率低于其它五组(P<0.01),饲粮低锰使破蛋率和软蛋率显著升高(P<0.01),第3组(73.8ppm Mn)破蛋率最低,第5组(153.8ppm Mn)软蛋率最低。其次,饲粮高锰和低锰都使蛋壳厚度和强度降低(P<0.01),同时也降低受精率(P>0.05)。受精蛋孵化率以第3组(73.8ppm Mn)最高(P<0.01),并可有效地防止雏鸡脱腱症的发生。作者建议,产蛋前期母鸡饲粮含锰在73.8——153.8ppm为佳;种鸡则为73.8——113.8ppm;而在蛋鸡生长发育阶段,饲粮含锰不得低于33.5ppm。 相似文献