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排序方式: 共有63条查询结果,搜索用时 15 毫秒
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Incorporation of a range of higher concentrations of CuSO4·5H2O in MS medium [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassay with 240 tobacco tissue cultures. Physiol. Plant 15, 473–497] significantly enhanced direct shoot bud induction and proliferation from cultured leaf and nodal explants taken from mature plants of Stevia rebaudiana. Shoot bud induction medium was supplemented with BAP (2.2 μM) and IAA (2.8 μM). When the concentration of CuSO4·5H2O in the induction medium was raised to 0.5 μM (five times the MS level, i.e. 0.1 μM) there was significant increase in percentage response along with increase in shoot bud number per explant. The shoots were healthy, well developed with dark green broader leaves. There was remarkable increase in total biomass and chlorophyll content at increased (0.5 μM) copper level in the medium. During proliferation stage also presence of high copper levels in the medium favoured increase in shoot bud number per explant. 相似文献
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在石灰性土壤上,通过盆栽试验研究了NaHCO3对耐缺Zn敏感品种水稻生长和Zn、Fe、Mn、Cu含量的影响。NaHCO3显著降低Zn敏感品种地上部和根部的干重,而对耐性品种没影响。NaHCO3减少Zn敏感品种ZN、Fe、Mn的含量,而对耐性品种影响很小,耐性品种和敏感品种的Cu含量不受NaHCO3的影响。以上结果表明:水稻耐缺Zn与水稻对土壤中NaHCO3的高忍耐力有关。 相似文献
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氮肥对不同玉米品种子粒微量元素含量和生物有效性的影响 总被引:1,自引:0,他引:1
研究田间施用氮肥对吉林省4个玉米品种子粒中Zn、Fe、Mn、Cu含量以及Zn与Fe生物有效性的影响。结果表明,施用氮肥可增加玉米子粒中Zn、Fe含量,过量施氮玉米子粒中Zn和Fe含量不再增加甚至呈下降趋势;子粒中Mn含量随氮肥增加而提高,Cu含量随氮肥增加而降低,4个品种中只有吉四单19在过量施氮时子粒Mn含量呈下降趋势。随氮肥水平提高,玉米子粒中Zn、Fe和Mn累积量呈递增趋势,Cu累积量变化不显著。全磷与这些矿物质元素的比值(P/Zn、P/Fe)表明,氮肥施用将显著降低玉米子粒中Zn和Fe的生物有效性。 相似文献
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Identification of quantitative trait loci (QTLs) for grain mineral elements can assist in faster and more precise development of micronutrient dense rice varieties through marker-assisted breeding. In the present study, QTLs were mapped for Fe and Zn concentrations in two BC2F3 mapping populations derived from the crosses of O. sativa cv Swarna with two different accessions of O. nivara. In all, 10 and 8 QTLs were identified for grain Fe and Zn concentrations in population 1, and 7 and 5 QTLs were identified in population 2, respectively. Eighty percent of the QTLs detected in both populations were derived from O. nivara. Five QTLs for Fe and three QTLs for Zn explained more than 15% phenotypic variance either in interval or composite interval mapping. The locations of O. nivara derived QTLs such as qFe2.1, qFe3.1, qFe8.2 and qZn12.1 were consistently identified in both the populations. Epistatic interaction was observed only between RM106 and RM6 on chromosome 2 and between RM22 and RM7 on chromosome 3 for Fe concentration in population 1. Sixteen candidate genes for metal homeostasis were found to co-locate with 10 QTLs for Fe and Zn concentrations in both the populations. Most of the Fe and Zn QTLs were found to co-locate with QTLs for grain yield and grain quality traits. Some of the major effect QTLs identified can be used to improve rice grain Fe and Zn concentrations. 相似文献
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Rongli Shi Yueqiang Zhang Xinping Chen Qinping Sun Fusuo Zhang Volker Römheld Chunqin Zou 《Journal of Cereal Science》2010
A long-term (1999–2007) field experiment was conducted to investigate the effects of three nitrogen (N) fertilization rates (0, 130, and 300 kg N/ha) on micronutrient density in wheat grain and its milling fractions. At maturity, grains were harvested and fractionated into flour, shorts, and bran for micronutrient and N analysis. N fertilization increased iron (Fe), zinc (Zn), and copper (Cu) density in wheat grain compared to the control. Increase of N application rate from 130 to 300 kg N/ha, however, did not further increase the three micronutrient densities in grain. Micronutrient concentrations were usually highest in the bran and lowest in the flour. High N application increased Zn and Cu densities in all three milling fractions and increased Fe concentration in shorts and bran but not in flour. N application did not affect the manganese (Mn) concentration in grain. N fertilization changed the proportions of Fe and Cu in flour and bran but did not affect the distribution of Zn. Because N fertilization increased micronutrient accumulation in wheat grain, proper management of N fertilization has the potential to enhance the nutritional quality of this important food. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(10):1039-1052
Abstract The relative effectiveness of Mehlich I (.025N H2SO4 + .05N HCl) and Mehlich III (0.2N CH3COOH + 0.25N NH4NO3 +.015N NH4F + .013N HNO3 + .001M EDTA) extractants as predictors of Mn, Cu and Zn uptake was assessed in a greenhouse experiment with four Delaware soils. The soils were adjusted to eight pH levels by addition of Ca(OH)2 or elemental S, and received comparable amounts of Mn, Cu and Zn as either (1) MnSO4 + CuSO4 + ZnSO4 or (2) Poultry Manure. Mehlich 1 and III extractable Mn and Zn, but not Cu, were well correlated in most instances. Excellent correlations were obtained between Mn uptake and Mehlich I and Mehlich III extractable Mn, for all soils and sources. In general, however, neither Zn nor Cu was found to correlate well with plant uptake. Based on this study, conversion to Mehlich III, as a routine soil test extractant for micronutrients, would not result in a significant improvement over the currently used Mehlich I extractant. 相似文献
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由于主要粮食作物中微量营养元素(特别是Zn 和Fe)的缺乏导致全世界范围内的人类微量营养元素缺乏症。野生二粒小麦(Triticum turgidum ssp. dicoccoides)是提高小麦籽粒Zn、Fe、蛋白质含量及改良小麦其他性状的重要种质资源。本研究以4 份野生二粒小麦及32 份野生二粒小麦与普通小麦(Triticum aestivum L.)杂交后代为材料, 进行籽粒中富含Zn、Fe 和蛋白质种质资源的筛选和鉴定。野生二粒小麦的后代材料表现出广泛的遗传变异。籽粒Zn、Fe 含量和蛋白质含量之间均呈极显著正相关关系, 说明这些性状能够通过育种方式达到共同提高的目的。试验共筛选到17 份Zn、Fe 和蛋白质含量均显著高于对照品种"石4185"的材料, 说明将来自野生二粒小麦的外源基因导入到普通小麦是提高小麦籽粒Zn、Fe 和蛋白质含量的有效途径。其中5份野生二粒小麦与普通小麦的杂交后代表现出较高籽粒Zn、Fe 和蛋白质含量的同时, 也具有较高的产量和优良的农艺性状。这些材料的获得为小麦生物强化育种提供了重要的物质基础。 相似文献
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J.I. Ortiz-Monasterio N. Palacios-Rojas E. Meng K. Pixley R. Trethowan R.J. Pea 《Journal of Cereal Science》2007,46(3):293
More than half of the world's population suffers micronutrient undernourishment. The main sources of vitamins and minerals (iron, zinc, and vitamin A) for low-income rural and urban populations are staple foods of plant origin that often contain low levels or low bioavailability of these micronutrients. Biofortification aims to develop micronutrient-enhanced crop varieties through conventional plant breeding. HarvestPlus, the CGIAR's biofortification initiative, seeks to breed and disseminate crop varieties with enhanced micronutrient content that can improve the nutrition of the “hard to reach” (by fortification or supplementation programmes) rural and urban poor in targeted countries/regions. In attempting to enhance micronutrient levels in maize and wheat through conventional plant breeding, it is important to identify genetic resources with high levels of the targeted micronutrients, to consider the heritability of the targeted traits, to explore the availability of high throughput screening tools and to gain a better understanding of genotype by environment interactions. Biofortified maize and wheat varieties must have the trait combinations which encourage adoption such as high yield potential, disease resistance, and consumer acceptability. When defining breeding strategies and targeting micronutrient levels, researchers need to consider the desired micronutrient increases, food intake and retention and bioavailability as they relate to food processing, anti-nutritional factors and promoters. Finally, ex ante studies are required to quantify the burden of micronutrient deficiency and the potential of biofortification to achieve a significant improvement in human micronutrient status in the deficient target population in order to determine whether a biofortification program is cost-effective. 相似文献