以绿洲盐化潮土为研究对象，通过采集6叶期典型缺锌玉米及其相邻正常玉米根际、非根际土壤和植株样品，研究了不同类别土壤锌形态特征和不同类型植株含锌量、吸锌量及土壤锌素从根系向地上部转运的差异及植株含锌量、吸锌量及土壤锌素转运率与各形态锌的相关性。结果表明，绿洲盐化潮土全锌含量平均为97.12 mg/kg，缺锌植株与正常植株、根际土壤与非根际之间都没有显著差异；土壤有效锌含量平均为0.60 mg/kg，高于北方石灰性土壤缺锌临界值(0.50 mg/kg)，缺锌植株根际土壤有效锌含量比正常植株根际土壤低42.70%，达到极显著差异水平。残留矿物态是绿洲盐化潮土最主要的锌形态，占全锌含量的79.43%；其次是晶形铁结合态、无定形铁结合态和松结有机态。交换态、碳酸盐结合态、松结有机态、氧化锰结合态锌含量均为根际土壤显著高于非根际土壤，正常植株显著高于缺锌植株。缺锌玉米茎叶含锌量只有14.64 mg/kg，低于玉米缺锌临界值(20 mg/kg)，比正常植株低52.30%，吸锌量比正常植株低66.52%，锌素转运率比正常植株低将近10百分点，这是绿洲盐化潮土上玉米缺锌的一个重要机制。玉米茎叶含锌量与Ex-Zn、CAB-Zn含量呈极显著正相关；茎叶吸锌量与WBO-Zn、OxMn-Zn、DTPA-Zn含量呈极显著正相关，与AOFe-Zn含量呈显著负相关；土壤锌素转运率与DTPA-Zn、CAB-Zn、WBO-Zn、OxMn-Zn含量呈显著正相关，与AOFe-Zn含量呈显著负相关。

Taking the saline fluvo-aquic soil area of Hexi Oasis as research object， rhizosphere and bulk soil and plant samples of typical Zn-deficient corn and its adjacent normal corn with 6 leaves were collected， studied the differences of Zn fraction characteristics in different types of soil and Zn concentrations， uptakes and transported ratio in different types of corn， the difference of zinc uptake and soil zinc transport from root to overground， and the amount of zinc in plants， as well as the correlations between plant Zn concentrations，uptakes， Zn transported ratio and Zn fractions were discussed in this paper. The results showed that total Zn content with an average of 97.12 mg/kg in saline fluvo-aquic soil，and had no significant difference between Zn-deficient and normal plants， also between rhizosphere and bulk soil. Available Zn content with an average of 0.60 mg/kg， which was below the deficiency level (DTPA-Zn < 0.50 mg/kg) in calcareous soil in northern China. Meanwhile， the available Zn contents in rhizosphere of Zn-deficient plant were 42.70% lower than normal plant extremely significant. Residual minerals were the main Zn form in saline fluvo-aquic soil， it accounted for 79.43% of total Zn， and followed by crystalline Fe oxides， amorphous Fe oxides and loose bound to organic matter. The Zn contents in rhizosphere soil of exchangeable form， bound to carbonates， loose bound to organic matter and bound to Mn oxides were all significantly higher than bulk soil， normal plant significantly higher than Zn-deficient plant. The shoot Zn concentration of Zn-deficient plant was only 14.64 mg/kg， which was below the critical value of Zn deficiency(20 mg/kg)， and 52.30% lower than that of normal corn. Meanwhile， the uptake of Zn-deficient plant was 66.52% lower and Zn transported ratio was nearly 10 percentage points lower than that of normal corn. This may be an important mechanism of Zn deficiency in corn in saline fluvo-aquic soil. The shoot Zn concentrations were positively correlated with Ex-Zn and CAB-Zn. The shoot Zn uptakes were positively correlated with WBO-Zn， OxMn-Zn and DTPA-Zn， and negatively correlated with AOFe-Zn contents. The Zn transported ratios were positively correlated with DTPA-Zn， CAB-Zn，WBO-Zn and OxMn-Zn， and negatively correlated with AOFe-Zn contents.

S156.4

国家自然科学基金(41967016、41261072)；甘肃省农业科学院科技创新专项(2015GAAS03)。