Singh Bal R, Timsina Yadu N, Lind Ole C, Cagno Simone, Janssens Koen
Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway.
Centre of Environmental Radioactivity, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway.
Front Plant Sci. 2018 Mar 9;9:307. doi: 10.3389/fpls.2018.00307. eCollection 2018.
Nearly half of the world cereal production comes from soils low or marginal in plant available zinc, leading to unsustainable and poor quality grain production. Therefore, the effects of nitrogen (N) rate and application time on zinc (Zn) and iron (Fe) concentration in wheat grain were investigated. Wheat ( var. Krabat) was grown in a growth chamber with 8 and 16 h of day and night periods, respectively. The N rates were 29, 43, and 57 mg N kg soil, equivalent to 80, 120, and 160 kg N ha. Zinc and Fe were applied at 10 mg kg growth media. In one of the N treatments, additional Zn and Fe through foliar spray (6 mg of Zn or Fe in 10 ml water/pot) was applied. Micro-analytical localization of Zn and Fe within grain was performed using scanning macro-X-ray fluorescence (MA-XRF) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The following data were obtained: grain and straw yield pot, 1000 grains weight, number of grains pot, whole grain protein content, concentration of Zn and Fe in the grains. Grain yield increased from 80 to 120 kg N ha rates only and decreased at 160 kg N ha g. Relatively higher protein content and Zn and Fe concentration in the grain were recorded with the split N application of 160 kg N ha. Soil and foliar supply of Zn and Fe (Zn + Fe), with a single application of 120 kg N haN at sowing, increased the concentration of Zn by 46% and of Fe by 35%, as compared to their growth media application only. Line scans of freshly cut areas of sliced grains showed co-localization of Zn and Fe within germ, crease and aleurone. We thus conclude that split application of N at 160 kg ha at sowing and stem elongation, in combination with soil and foliar application of Zn and Fe, can be a good agricultural practice to enhance protein content and the Zn and Fe concentration in grain.
世界上近一半的谷物产量来自植物有效锌含量低或处于边缘水平的土壤，这导致了不可持续且质量不佳的谷物生产。因此，研究了施氮量和施肥时间对小麦籽粒中锌（Zn）和铁（Fe）含量的影响。小麦（品种Krabat）在生长室中种植，昼夜时长分别为8小时和16小时。施氮量分别为29、43和57毫克氮/千克土壤，相当于80、120和160千克氮/公顷。锌和铁以10毫克/千克生长介质的量施用。在其中一种施氮处理中，通过叶面喷施（10毫升水/盆中含6毫克锌或铁）额外施用锌和铁。使用扫描宏观X射线荧光（MA-XRF）和激光烧蚀-电感耦合等离子体质谱（LA-ICP-MS）对籽粒内的锌和铁进行微观分析定位。获得了以下数据：籽粒和秸秆产量/盆、千粒重、每盆粒数、全籽粒蛋白质含量、籽粒中锌和铁的含量。籽粒产量仅在施氮量从80千克氮/公顷增加到120千克氮/公顷时增加，在160千克氮/公顷时下降。在160千克氮/公顷的分次施氮处理下，籽粒中的蛋白质含量以及锌和铁含量相对较高。与仅在生长介质中施用相比，在播种时单次施用120千克氮/公顷并结合土壤和叶面施用锌和铁（锌+铁），使锌含量增加了46%，铁含量增加了35%。对切片籽粒新鲜切割区域的线扫描显示，锌和铁在胚、胚乳痕和糊粉层中共定位。因此，我们得出结论，在播种和茎伸长时以160千克/公顷分次施氮，并结合土壤和叶面施用锌和铁，可能是提高籽粒蛋白质含量以及锌和铁含量的良好农业措施。
