海涂柑桔缺铁敏感性差异机理研究

通过田间调查取样和砂培试验，分别测定不同桔苗砧穗组合的根系还原力和铁吸收动力学由，对比研究了海涂不同砧木柑桔缺铁失绿的敏感性差异。试验证明，抗缺铁能力较强的构头橙砧（Ｃ．ａｕｒａｎｔｉｕｍＬｉｎｎ）的桔苗的叶片中的“全铁”和“活性铁”含量和根系还原力均高于抗缺铁能力弱的枳砧（Ｐ．ｔｒｉｆｏｌｉａｔｅＬ．）桔苗；同时，其铁吸收动力学曲线表现出具有较大的Ｖｍａｘ和较小的Ｋｍ值；在ＨＣＯ３－逆境条件下，枳砧苗的Ｖｍａｘ下降较为明显，而构头橙砧的变化幅度相对比较小。

The Susceptibility of Iron Chlorosis on Genotypes of Citrus Rootstock in Beach-silt

A study of the susceptibility of iron chlorosis on genotypes of citrus rootstocks was carried out in beach-silt of Zhejiang province. It was found the Goutou sour orange(C. aurantium Linn.) is more tolerant to iron chlorosis while Trifoliate orange (P. trifoliate L.) is susceptible. The contents of total iron and active iron of Goutou leaves were more than of Trifoliate,and also the root reduction capacity and iron uptake rate were higher. In the iron uptake rate curve, Goutous's Vmax is higher and its Km is lowew. Under the conditions of HCO3- induced iron stress Trifoliate showed the significant decrease in Vmax while Goutou decreased relatively smaller.