Inductively coupled plasma mass spectrometry was applied to determine the contents of iron and manganese in teas from Fujian province.The distribution and accumulation characteristics in different parts of a tea plant were analyzed.The results showed that the mineral concentrations significantly differed among the varieties of teas studied.The iron contents ranged from 73.36 mg · kg-1 to 284.85 mg · kg-1 with a mean of 125.60 mg · kg-1,and manganese from 201.86 mg · kg 1 to 4 905.78 mg · kg-1 with a mean of 1 651.24 mg · kg-1.Overall,the black and the green teas contained more iron than oolong tea,whereas,oolong tea had a higher manganese content than the green or the black tea.There was no significantly difference on manganese content found between the green and the black tea.Significantly differences in the mineral contents were also shown among different parts of a tea plant.The iron concentrations in different parts ranked in the order of the fine roots (6 265.07 mg · kg-1) ＞ taproots (3 250.77 mg · kg-1) ＞ main stem (2 178.56 mg · kg-1) ＞ stem side (1 025.81 mg · kg-1) ＞ old leaves (347.50 mg · kg 1) ＞ young leaves (135.70 mg · kg-1).Thus,most of the iron was absorbed and accumulated in the roots and stems on a tea plant.On the other hand,the manganese in old leaves was the highest (P＜0.05),and evenly distributed in other parts throughout the plant.In general,Tieguanyin and Meizhan teas had greater iron or manganese contents as well as on enrichment coefficients in different parts of a tea plant than Jinguanyin or Jinxuan.%采用ICP-MS法测定茶叶及茶树中铁锰含量,探讨铁锰在茶树不同器官中分布及富集规律.结果表明:茶叶中铁锰含量差异较大,铁含量为73.36～284.85 mg·kg-1(均值为125.60),茶叶中锰含量为201.86～4 905.78 mg · kg-1(均值为1 651.24);总体而言,红茶和绿茶中铁含量高于乌龙茶,而乌龙茶中锰含量明显高于红茶和绿茶,红茶和绿茶之间铁锰含量相近.不同茶树品种体内铁锰含量有较大差异,各器官铁含量表现为须根(6 265.07mg·kg-1)＞主根(3 250.77mg· kg-1)＞主茎(2 178.56 mg·kg-1)＞侧茎(1 025.81mg· kg-1)＞老叶(347.50 mg· kg-1)＞新叶(135.70mg· kg-1),铁主要在茶树根系和茎中积累;各器官锰含量表现为老叶含量最高,其他器官分布规律不明显.茶树各器官铁富集系数分别为0.002～0.225,锰富集系数为5.25～12.63,茶树对锰富集能力较强.总体而言,梅占和铁观音各器官铁锰含量及富集系数高于金观音和金萱.
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