Effect of wastewater irrigation on mineral com‐position of corn and sorghum plants in a pot experiment

Effect of wastewater irrigation was investigated on mineral composition of corn and sorghum plants in a pot experiment. The ranges for the concentration of different minerals in corn plants were 0.67–0.89% calcium (Ca), 0.38–0.58% magnesium (Mg), 0.09–1.29% sodium (Na), 0.81–1.87% nitrogen (N), 1.81–2.27% potassium (K), 0.12–0.16% phosphorus (P), 190–257 mg/kg iron (Fe), 3.5–5.6 mg/kg copper (Cu), 37.1–44.5 mg/kg manganese (Mn), 21.6–33.6 mg/kg zinc (Zn), 1.40–1.84 mg/kg molydbenum (Mo), 11.0–45.7 mg/kg lead (Pb), and 2.5–10.8 mg/kg nickel (Ni). Whereas for sorghum plants, the ranges were: 0.56–0.68% Ca, 0.19–0.32% Mg, 0.02–0.27% Na, 0.69–1.53% N, 1.40–1.89% K, 0.10–0.14% P, 190–320 mg/kg Fe, 3.8–6.0 mg/kg Cu, 29.2–37.6 mg/kg Mn, 21.1–29.9 mg/kg Zn, 2.2–3.7 mg/kg Mo, 12.3–59.0 mg/kg Pb, and 2.5–15.2 mg/kg Ni. Heavy metals such as cobalt (Co) and cadmium (Cd) were below detection limits at mg/kg levels. The concentrations of Ca, N, K, P, Cu, and Mn in corn plants were in the deficient range except for Mg, Fe, Zn, and Al. The concentrations of Ca, N, P, K, Cu, Mn, Mg, and Zn in sorghum plants were in the deficient range except for Fe and aluminum (Al). The analysis of regression indicated a strong interaction between Pb, Ni, Ca, and Fe in corn and sorghum plants. In conclusion, waste water irrigation did not increase mineral concentrations of either macro‐ and micro‐elements or heavy trace metals in corn and sorghum plants to hazardous limits according to the established standards and could be used safely for crop irrigation.     

Comparison of a microwave digestion system to other digestion methods for plant tissue analysis

Abstract

Most digestion procedures for the preparation for plant tissue for elemental analysis are often very laborious. Elemental contents of plant tissue prepared by microwave digestion were compared to those obtained by conventional dry ashing and sulfuric acid‐hydrogen peroxide wet digestion. All three digestion methods produced comparable quantitative values for the elements P, K, Ca, Mg, Fe, Mn, Zn, and Cu for all plant materials used. Thus, the microwave digestion technique was shown to be a viable rapid method for digesting relatively small numbers of samples prior to elemental analysis.     

遵义市部分烟区烤烟中、微量元素含量及其空间分布

【目的】作为烟草生长发育所必需的营养元素,中、微量元素对于协调烟株生理机能、烤烟产量、品质的形成和增强抗病能力有着大量元素不可替代的作用。本研究基于野外取样与室内检测所获得的烟叶养分信息,旨在探求遵义市部分烟区烤烟烟叶中微量元素特征与空间分布情况,为该地烤烟生产养分分区管理、配方施肥技术和化肥减量提效提供科学参考。 【方法】运用经典统计学方法,初步对研究区烤烟烟叶中微量元素的丰缺状况进行分析评价,并结合 GPS 定位,以地统计学的半变异函数为工具,定量分析了研究区烟叶中微量元素的空间变异特征,采用 Kriging 插值法,得到烟叶中微量元素含量的空间分布格局。 【结果】1) 研究区 C₃F 等级烟叶 7 种中微量元素含量平均值分别为 Ca 20.3 g/kg、Mg 3.7 g/kg、Cu 4.42 mg/kg、Zn 34.85 mg/kg、Fe 229.81 mg/kg、Mn 205.43 mg/kg、Mo 0.25 mg/kg,含量范围分别为 Ca 14.7～27.3 g/kg、Mg 1.3～8.0 g/kg、Cu 1.69～8.83 mg/kg、Zn 12.31～56.11 mg/kg、Fe 141.62～339.00 mg/kg、Mn 66.21～426.11 mg/kg、Mo 0.06～0.60 mg/kg,各元素变异系数在 12.8%～48.7% 之间,均表现为中等强度变异;参照烟叶中微量营养元素分级标准,研究区烟叶适宜范围内钙占 95.2%,高水平锰含量占 65.1%,低水平镁、铜、锌、铁含量分别占 26.5%、55.4%、32.5%、20.5%,适宜水平镁、铜、锌、铁分别占 48.2%、25.3%、63.9%、79.5%,烟叶钼含量总体较缺乏。2) 研究区烟叶中 Ca、Mg、Zn 和 Fe 符合正态分布,Cu、Mn、Mo 经对数转化后均符合正态分布,分别选择指数模型作为 Ca、Cu、Fe、Mo 的最优拟合理论模型,Mg、Zn、Mn 为高斯模型,得出烟叶中 Ca、Mg、Cu、Zn、Fe、Mn、Mo 7 种元素各项异性比均大于 1,块金系数分别为 43.8%、26.9%、31.0%、58.4%、69.0%、32.6%、42.7%,变程分别为 148.099、137.407、15.554、18.723、25.624、88.770、74.749 km。 【结论】研究区烟叶 Ca 含量基本在适宜范围内,Mn 含量总体较高,Mg、Cu、Zn、Fe 含量基本在低–适宜水平,Mo 较缺乏。地统计分析表明:7 种元素均具有空间各向异性;空间变异指标块金系数大小顺序为 Fe > Zn > Ca > Mo > Mn > Cu > Mg,均为中等空间相关性;空间自相关范围由大到小依次为 Ca、Mg、Mn、Mo、Fe、Zn、Cu。采用地统计插值绘制的空间分布图,直观地反映了研究区烟叶中微量营养元素的含量分布状况。     

Essential and toxic elements in seafood available in poland from different geographical regions

The concentrations of 15 elements (Cu, Fe, Mn, Zn, Co, Ni, Cr, Se, Cd, Pb, Hg, Ca, Na, K, and Mg) were determined in the edible parts of shellfish on sale in the local market in Gdańsk. The samples consisted of three groups--crustaceans, molluscs, and surimi--that are processed to different degrees. For the purposes of this analysis, they were dried, homogenized, and digested in an automatic microwave system. The samples were analyzed quantitatively for Cu, Zn, Fe, Mn, Co, Ni, Cr, Mg, Na, K, and Ca (F-AAS), Cd and Pb (GF-AAS), Se (HG-AAS), and Hg (CV-AAS). The elemental levels detected in shellfish were compared to those in cod, herring, pork, beef, chicken, and eggs. The recommended dietary allowance (RDA) of essential elements and the provisional tolerable weekly intake (PTWI) of toxic elements were estimated. With factor analysis of the data, taxonomically different groups of raw and processed shellfish could be distinguished.     

Searching the most appropriate sample pretreatment for the elemental analysis of wines by inductively coupled plasma-based techniques

Different sample preparation methods were evaluated for the simultaneous multielement analysis of wine samples by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). Microwave-assisted digestion in closed vessel, thermal digestion in open reactor, and direct sample dilution were considered for the determination of Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Y, Mo, Cd, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Tl, Pb, and Bi in 12 samples of red wine from Valencia and Utiel-Requena protected designation of origin. ICP-MS allows the determination of 17 elements in most of the samples, and using ICP-OES, a maximum of 15 elements were determined. On comparing the sample pretreatment methodology, it can be concluded that the three assayed procedures provide comparable results for the concentration of Li, Na, Mg, Al, K, Ca, Mn, Fe, Zn, and Sr by ICP-OES. Furthermore, ICP-MS data found for Cu, Pb, and Ba were comparable. Digestion treatment provides comparable values using both total decomposition in open system and microwave-assisted treatment for Cu by ICP-OES and for Cr, Ni, and Zn by ICP-MS. Open vessel total digestion provides excess values for Cr, Mn, Fe, and Zn by ICP-OES and defect values for Se. However, direct measurement of diluted wine samples provided uncomparable results with the digestion treatment for Mn, Cu, Pb, Zn, Ba, and Bi by ICP-OES and for Mg, Cr, Fe, Ni, and Zn by ICP-MS. Therefore, it can be concluded that microwave-assisted digestion is the pretreatment procedure of choice for elemental analysis of wine by ICP-based techniques.     

Inductively coupled plasma optical emission spectrometric determination of minerals in thyme honeys and their contribution to geographical discrimination

Twenty-four Spanish thyme honey samples were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES). Twenty-four minerals were quantified for each honey. The elements Al, As, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Na, P, Pb, S, Se, Si, Sr, and Zn were detected in all samples; seven elements are very abundant (Ca, K, Mg, Na, P, S, and Si), and six are not abundant (Al, Cu, Fe, Li, Mn, and Zn). Eleven of them are trace elements (As, Ba, Cd, Co, Cr, Ni, Mo, Pb, Se, Sr, and V) at <1 mg kg(-)(1). Classification of thyme honeys according to their origin (coast, mountains) was achieved by pattern recognition techniques on the mineral data. By means of principal component analysis, a good separation by geographical origin is obtained when scores for the two first principal components are plotted. Classification functions of 11 metals (Al, As, Cr, Cu, K, Li, Mg, Na, P, S, and V) were obtained using stepwise discriminant analysis and applied to classify correctly approximately 100% of the honey samples.     

Element interconnections in Lotus japonicus: A systematic study of the effects of element additions on different natural variants

Lotus japonicus was used to study the distribution and interconnections of 15 elements in plant tissues, including essential and non-essential elements: boron (B), sodium (Na), magnesium (Mg), potassium (K), calcium (Ca), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), strontium (Sr), molybdenum (Mo), cadmium (Cd) and cesium (Cs). Large amounts of B and Ca accumulated in plant leaves, while Fe, Na, Ni, As and Cd tended to mainly occur in the roots, and Mo was the only element to accumulate in the stems. The elemental compositions within plants were severely disturbed by treatment with toxic elements. Competition between element pairs in the same group (e.g. K and Cs; Ca and Sr) was not found. Iron, Cu and Zn accumulation were induced by Cd and Ni addition. When natural variants grew in a nutrition solution with subtoxic levels of As, Cd, Cs, Ni, Mo and Sr, intriguing relationships between the elements (such as Fe, As and K; Mg and Ni; Mn and Ca) were revealed using principal-component analysis. This study on the plant ionome offers detailed information of element interactions and indicates that chemically different elements might be closely linked in uptake or translocation systems.     

重庆缙云山酸沉降背景下针阔混交林水化学特征初步研究

选取三峡库区缙云山小流域针阔混交林作为研究对象,对其大气降水、穿透雨、树干茎流、地表径流等水文过程中的pH值及Na+、K+、Ca2+、Mg2+等离子含量进行研究,结果表明:(1)大气降水pH值为5.31,呈酸性,已属于酸雨范围(pH<5.65)。相对于大气降水,针阔混交林穿透雨和树干茎流离子含量均大幅增加。穿透雨和树干茎流中,Mg、Cu元素的变异系数均小于大气降水,而K、Zn和Mn均大于大气降水。地表径流中Ca元素含量最高,为16.416mg/L,Mn元素含量最低,几乎检测不到。各元素含量排序为:Ca>K>Na>Mg>Zn>Fe>Cu>Mn。地下径流中,Ca元素是含量增加最多的养分元素,各元素含量排序为:Ca>K>Na>Mg>Zn>Cu>Fe=Mn。(2)Cu元素在穿透雨和树干茎流中均出现了负淋溶,其余各元素浓度均有所增加。如果林木长期处于酸雨逆境下,将会导致部分营养元素大量流失,并最终造成林木营养亏损且影响其生长。     

X‐ray fluorescence analysis of small leaf samples mixed with cellulose or boric acid

Abstract

X‐ray fluorescence (XRF) is an effective and rapid technique for the analysis of many mineral elements in plant tissue. Plant samples sometimes are too small to make good pellets and to provide good XRF analyses. Leaf tissue was mixed with cellulose or boric acid at different ratios to assess whether pellets from these mixtures could be analyzed by XRF and to determine the effects of these inert substances on analysis of Al, Ca, Cl, Cu, Fe, K, Mg, Mn, P, S, Si, and Zn. Concentrations of all elements decreased linearly at all leaf/cellulose ratios. Concentrations of Mn, Fe, Zn, and Cu decreased linearly at all leaf/boric acid ratios, but concentrations of the other elements decreased linearly only when leaf/boric acid ratios were above about 40/60, and decreases in concentration of these other elements were more pronouned at leaf/boric acid ratios below 40/60. Concentrations of P, S, Cl, K, Mg, Ca, Si, and Al were higher in leaf/boric acid than in leaf/cellulose pellets, and similar concentrations were noted for Cu, Mn, Fe, and Zn in both kinds of pellets. Mechanically shaking cellulose with leaf tissue generally resulted in higher mineral element concentrations than if samples were mixed by hand. Cellulose would be the preferred inert substance to mix with plant samples if plant samples are below ～40 mg in size. Small samples of plant tissue can effectively be analyzed by XRF when mixed with cellulose or boric acid.     

Importance of acid‐insoluble residue in plant analysis for total macro and micro elements

Abstract

Insoluble siliceous residues remaining after HNO₃/HClO₄ decomposition of the plant tissues National Bureau of Standards, standard reference materials spinach (Spinacea oleracea), orchard leaves and tomato leaves (Lycopersicon escuientum), contained varying quantities of the macro and micro elements Na, K, Mg, Ca, Mn, Fe, Cu and Zn. For the different samples with total element concentrations ranging from 11 μg/g (Cu in orchard leaves) to 45,000 μg/g (K in tomato leaves), residues contained element concentrations ranging from 0.05 to 88 times the respective concentrations in the samples. Contributions of residues to element concentrations in the plant tissues varied from 0.04 to 42% of the total concentrations. Overall, these constituted negligible (ca 0.1% for Mg and Ca), small (0.5% for Zn, Mn, K and 1% for Cu), and large (6% for Fe, 28% for Na) contributions depending on sample and analyte. Residue contributions to total element concentrations of plant tissues must be considered for reliable estimations of macro and micro elements.     

Inductively coupled plasma emission spectroscopic determination of nine elements in infant formula: collaborative study

Results from a collaborative study of a method for the determination of 9 elements in infant formula, using inductively coupled plasma emission spectroscopy, are reported. Six collaborators analyzed 6 infant formulas for native and spiked levels of Ca, Cu, Fe, Mg, Mn, P, K, Na, and Zn. The within-laboratory and between-laboratory coefficients of variation were generally (69 of 108 samples) below 9% for all elements determined in all samples. Most of the average recoveries of the elements from spiked samples ranged from 90 to 105%. The method has been adopted official first action for determining Ca, Cu, Fe, Mg, Mn, P, K, Na, and Zn in infant formula.     

中国烤烟中部叶矿质营养元素浓度状况

于20012～004年,从重点植烟县采集了410个烤烟中部叶样品,运用ICP测定方法和概率密度分布函数对其氮、钾、磷、钙、镁、硫、锰、铜、锌、硼、钠、铁、氯13个矿质元素的浓度特征进行了分析。结果表明:1)大量元素的变异系数较小,中量元素其次,微量元素较大;2)除氮、镁、硫、铜、锌、钠、铁外,其他元素的浓度在品种之间的差异显著,但不同指标在品种之间的高低秩序不同,例如,云烟87的磷浓度显著地高于云烟85、K326的磷浓度,而钾浓度按K326、云烟87、云烟85依次降低;3)所有元素在省份之间的差异极显著,但不同元素在地区之间的高低秩序不同,例如,河南烟叶的钾浓度显著地低于其他省份,贵州烟叶的氯离子浓度显著地高于其他地方;4)钾、磷、钙、硫、硼、钠在烟叶中的浓度符合正态分布,氮、镁、氯、锰、铜、锌、铁在烟叶中的浓度符合对数正态分布;5)氮、磷、钾、钙、镁、硫、锰、铜、锌、硼、钠、铁、氯的正常浓度范围分别为1.18～2.34、0.11～0.30、0.87～2.83、0.99～3.64、0.1～0.8、0.25～0.9、25.18～601.65、2.1～37.271、3.11～105.421、2.6～55.62、163.02～503.11、97.6～384.2、0.07～0.53(氮、磷、钾、钙、镁、硫、氯的单位为%,其余为mg/kg);6)氮、钾、氯、钾/氯比四个因素符合国际型优质烟叶质量标准的概率只有0.726、0.379、0.193、0.829,目前我国烤烟营养不够协调的主要方面是养分浓度偏低。     

Wastewater Reuse for Alfalfa Production in the Gaza Strip

Geography, population growth, and politics combine to make the Gaza Strip a worst-case scenario for water resource planners. Potable water sources are shrinking while at the same time, the proportion of potable water used for irrigation is increasing. To assess whether water from wastewater treatment plants could be safely used for irrigation, this study collected 51 treated wastewater, 51 sludge, 44 soil, 30 alfalfa, and 24 oranges and lemon samples and analyzed the samples for major and trace elements. Both Inductively Coupled Plasma - Optical Emission Spectroscopy (ICP/OES) and X-ray fluorescence (XRF) were used for the determination of Ag, Al, As, B, Ba, Br, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, Se, Sr, Zn, Zr, Th, and U in digested and solid samples, respectively. Treated wastewater characteristics showed a very good agreement with the guidelines of many developed countries. Moreover, none of the tested parameters in soil showed concentrations exceeding their corresponding background values. For alfalfa, both ICP/OES and XRF showed Zn concentrations in leaves (36–42 mg/kg, respectively) higher than in root (19–31 mg/kg, respectively). The Cu showed also the same trend as Zn. No significant variation was observed between the concentrations of Cr and Mn in plant parts; concentrations of Co and Pb were two times higher in roots than in leaves and stems. The findings confirm that treated wastewater is safe to use for irrigation in Gaza. Collecting and reclaiming this water can contribute to wise use of each drop of water available.     

Annual and Seasonal Variations of Trace Metals in Atmospheric Suspended Particulate Matter in Islamabad, Pakistan

Total Suspended particulate matter (TSP) in urban atmosphere of Islamabad was collected using a high volume sampling technique for a period of one year. The nitric acid–perchloric acid extraction method was used and the metal contents were estimated by atomic absorption spectrophotometer. The highest mean concentration was found for Ca at 4.531 µg/m³, followed by Na (3.905 µg/m³), Fe (2.464 µg/m³), Zn (2.311 µg/m³), K (2.086 µg/m³), Mg (0.962 µg/m³), Cu (0.306 µg/m³), Sb (0.157 µg/m³), Pb (0.144 µg/m³) and Sr (0.101 µg/m³). On an average basis, the decreasing metal concentration trend was: Ca > Na > Fe > Zn > K > Mg > Cu > Sb > Pb > Sr > Mn > Co > Ni > Cr > Li > Cd ≈ Ag. The TSP levels varied from a minimum of 41.8 to a maximum of 977 µg/m³, with a mean value of 164 µg/m³, which was found to be higher than WHO primary and secondary standards. The correlation study revealed very strong correlations (r?>?0.71) between Fe–Mn, Sb–Co, Na–K, Mn–Mg, Pb–Cd and Sb–Sr. Among the meteorological parameters, temperature, wind speed and pan evaporation were found to be positively correlated with TSP, Ca, Fe, K, Mg, Mn and Ag, whereas, they exhibited negative relationships with relative humidity. On the other hand, Pb, Sb, Zn, Co, Cd and Li revealed significant positive correlations with relative humidity and negative with temperature, wind speed and pan evaporation. The major sources of airborne trace metals identified with the help of principle component analysis and cluster analysis were industrial emissions, automobile exhaust, biomass burning, oil combustion, fugitive emissions, resuspended soil dust and earth crust. The TSP and selected metals were also studied for seasonal variations, which showed that Na, K, Zn, Cu, Pb, Sb, Sr, Co and Cd peaked during the winter and remained lowest during the summer, while Ca, Fe, Mg and Mn were recorded highest during the spring.     

Variation of major minerals and trace elements in seeds of tartary buckwheat (Fagopyrum tataricum Gaertn.)

Tartary buckwheat (Fagopyrum tataricum Gaertn.) contains protein of high nutritional value, polyphenols, vitamins and minerals. It is one of the most important minor crops in China and has a great potential as a health and functional food. However, information on the elemental mineral composition of its seeds remains limited. The concentrations of Cu, Zn, Fe, K, and Mg in seeds of 123 tartary buckwheat accessions from the same cultivation were studied by means of flame atomic absorption spectrometry. The results revealed that the average concentrations of Cu (x₁), Zn (x₂), Fe (x₃), K (x₄), and Mg (x₅) elements in the accessions are 19.49 (with a range of 5.74–36.01 mg/kg), 27.41 (8.44–66.63 mg/kg), 656.24 (21.8–3,990 mg/kg), 3,639.23 (1,737–5,831 mg/kg), and 1,523.89 mg/kg (729–3,104 mg/kg) respectively. Among them, Fe concentration has the highest coefficient of variation (114.7 %). The results also revealed five significant positive correlations among Cu, Zn, Fe, K, and Mg concentrations. Therefore, distinct genotypes with high concentration of mineral elements should be effective for the development of special buckwheat varieties and improvement of its food nutritional quality.     

福建烟区土壤中量和微量营养元素含量状况的研究

福建烟区土壤中量和微量元素的平均含量交换性钙为519.33mg/kg,交换性镁为34.49mg/kg,有效硫为27.91mg/kg,有效铁为61.07mg/kg,有效锰为13.99mg/kg,有效铜为3.09mg/kg,有效锌为3.32mg/kg,有效硼为0.17mg/kg,水溶性氯为26.30mg/kg。福建烟区土壤交换性镁、有效硼含量不足,有效铁、锰含量丰富,有效铜、锌含量较适宜。     

DIAGNOSIS AND RECOMMENDATION INTEGRATED SYSTEM (DRIS) FOR EVALUATING NUTRIENT STATUS OF COTTON (GOSSIPIUM HIRSUTUM)

Diagnosis and Recommendation Integrated System (DRIS) approach was employed to monitor the nutrient status of cotton (Gossipium hirsutum) in southwestern districts of Punjab, North-West India. DRIS norms for macro, secondary and micro nutrients in cotton plant are developed. Considering these DRIS norms, the most limiting nutrient for cotton plant in the region is identified along with the order in which the other nutrients become limiting. The DRIS approach indicated that 11, 3, 8, 5, 2, 4, 2, 3, 6 and 2 percent of the total cotton leaf samples collected were low in nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu), respectively. Leaf tissues of cotton plant were also found to contain high to excessive content of N, P, K, Ca, Mg, S, Fe, Mn Zn and Cu in 11, 7, 15, 19, 25, 18, 66, 33, 9 and 25 percent samples, respectively. DRIS derived sufficiency concentration ranges obtained from survey of cotton fields in this region were 2.22 to 5.20% N, 0.20 to 0.47% P, 1.05 to 2.14% K, 1.66 to 2.86% Ca, 0.34 to 0.57% Mg, 0.65 to 1.11% S, 106 to 172 mg kg^?1 Fe, 35 to 68 mg kg^?1 Mn, 18 to 33 mg kg^?1 Zn, and 5 to 8 mg kg^?1 Cu. The results elucidate that DRIS technique can be used for macro, secondary and micro nutrients indexing of cotton crop irrespective of its cultivar.     

不同早实核桃品种叶片矿质元素含量变化及其与产量的关系

试验于2010~2011年连续2年以济源市4个早实核桃品种香玲、鲁光、中林1号、薄丰为试材进行了对比试验,研究了不同采样时期叶片中N、 P、 K、 Ca、 Mg、 Fe、 Cu、 Mn、 Zn 9种矿质营养元素的含量变化及其与产量的关系。结果表明,早实核桃叶片中9种元素的含量在年周期内呈规律性变化,含量高低依次为 Ca＞N＞Mg＞P＞K,Fe＞Mn＞Zn＞Cu。不同品种各元素的含量变幅最大为127.69~169.53 mg/kg（Mn）,最小为2.1~92.26 g/kg（K）。不同早实核桃品种叶片内矿质元素含量的年变化趋势表现为N、 P、 K总体上呈下降趋势,最高含量为展叶期（4月20日）分别为36.79、 5.54、 2.93 g/kg,最低在落叶前期（9月28日）,分别为17.45、 2.66、 1.86 g/kg;Ca、 Mg、 Fe、 Mn 4元素含量的变化总体上表现为前期低后期高;Cu、Zn含量的变化有差异但差异不明显。总的来看, 5~7月份,即新梢速长期（5月20日）至硬核期（7月20日）是核桃树养分稳定的时期, 叶片中N、 P、 K含量之间呈极显著的正相关, N、 P与Ca、 Mg、 Mn、 Cu间呈极显著的负相关,可以认为N、 P、 K之间存在增效作用,Ca、 Mg、 Mn、 Cu 对N、 P 和 K 均存在一定的拮抗作用。元素含量与产量的相关分析表明,N、 P、 K在新梢速长期均与产量达（极）显著正相关,相关系数分别为0.819、 0.843和0.895。因此, 利用叶片进行营养诊断最佳,采样时间以新梢速长期（5月20日前后）为宜。     

Determination of Major and Trace Elements in Plant Samples by Inductively Coupled Plasma–Mass Spectrometry

The determination of several trace elements [arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), molybdenum (Mo), nickel (Ni), and lead (Pb)] in plant samples using inductively coupled plasma–mass spectrometry (ICP‐MS) was evaluated. It was established experimentally that moderate amounts (0.2–2%) of dissolved solids decreased the analyte signals significantly. Internal standardization with Rh was efficiently used to compensate for these matrix effects. The accuracy of the method was verified using reference materials digested according to two different procedures: dry ashing and microwave digestion. No significant differences were observed between measured concentrations and certified values. The investigation was next extended for the determination of major elements [aluminum (Al), boron (B), calcium (Ca), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), phosphorus (P), and zinc (Zn)] on the same reference materials. The ICP‐MS values agree well with the values supplied. However, it appeared that Sc was the most useful internal standard for major elements.     

Effect of zinc on some important macro‐ and microelements in blackgram leaves

Abstract

Blackgram (Vigna mungo L.) plants were grown in glasshouse earthen pot experiment. Zinc (Zn) was applied to the soil at different concentrtions. Plant leaf samples were analysed at the age of 30, 45, and 65 days after sowing. The accumulation of Zn in the plant increased with the applied Zn concentration to the soil. Also a variation in the uptake of Zn by the plant with age has been observed. The excess accumulation of Zn in the plant induced a reduction in the content of some macro‐ [calcium (Ca), magnesium (Mg), potassium (K), and sodium (Na)] and micro‐elements [iron (Fe), manganese (Mn), and copper (Cu)] in the plant leaves. Furthermore, the Ca: Zn ratio decreased with increasing Zn concentration which clearly indicates a toxic Zn effect on blackgram plants.