不同P-Zn配比对小麦幼苗微量元素营养的影响

采用了螯合-缓冲营养液培养方法对小麦进行了苗期培养试验,在3个P水平(0,0.6,3.0 mmol/L)和3个Zn水平(0,3,30 μmol/L)的完全组合下对小麦苗期生长及Zn、Fe、Cu、Mn营养进行了研究,旨在为小麦微肥施用提供理论依据.结果表明,P、Zn的正常供应促进了小麦生长,二者的缺乏与过量均会抑制小麦发育,且这种影响在冠部表现得更为明显.在小麦苗期,Zn与Cu的吸收存在明显的拮抗作用,但供Zn则促进了Zn和Cu的转运,而Mn转运则受到了抑制;过量供Zn时,大量Zn被转运到冠部,同时明显抑制了(Fe+Cu+Mn)的吸收总量;P的供应显著地抑制了Fe的吸收,但P的供应提高了Zn、Cu、Mn的转运率;P、Zn在对Zn与Fe、Cu、Mn间吸收竞争的影响中,Zn本身的影响要比P的影响更为明显,供Zn明显促进了小麦幼苗对Zn的吸收;在小麦幼苗冠部,Zn与Fe的竞争中,供P利于Zn的吸收,缺P则利于Fe的吸收;而Zn与Cu以及Zn与Mn间的竞争中,缺磷时利于Zn的吸收,供磷后则利于Cu和Mn的吸收.总之,小麦幼苗Zn、Fe、Cu、Mn营养中,P、Zn的不同配比会不同程度地改变Zn与Fe、Cu、Mn的协同或拮抗效应.

Effect of Different Combinations of P and Zn on the Micronutrients of Wheat Seedling

A culture experiment was conducted to evaluate the growth and the nutrition of Zn,Fe,Cu,Mn of wheat plants at the seedling stage in chelater-buffered solution.Zn rates were applied at three levels of deficient (0 μmol/L),normal (3 μmol/L),excess (30 μmol/L) and P was also designed in three rates,namely,0 (insufficiency),0.6 (normal),3.0 (excess) mmol/L.The results showed that the growth of wheat was increased under normal P and Zn supply,but there would be depressed if excess or no P and Zn addition to culture solution,and these effects were stronger to the shoots than that of the roots;There was obvious antagonism between Zn and Cu at wheat seedling stage,but the translocations from root to shoot of Zn and Cu were increased under the supply of Zn,while that of Mn was decreased;A large mount of Zn was translocated to the shoot under excess Zn supply,and the total translocation of (Fe+Cu+Mn) was decreased drastically at the same time.The uptake of Fe was inhibited by the P supply,but the translocation ratio of Zn,Cu and Mn increased under the P supply;the effect of Zn itself was more remarkable than P on the uptake between Zn and Fe,Cu,Mn,the uptake of Zn was increased obviously under the Zn supply.To the shoot of wheat seedling,the uptake of Zn was easier than Fe under P supply,but the uptake of Fe overmatched that of Zn without P supply;For Zn and Cu,the uptake of Zn excelled that of Cu with no P supply,but the uptake of Cu outbalanced Zn after P supply,the same as the uptake between Zn and Mn.In conclusion,the different combinations of Zn and P would change the synergism or antagonism between Zn and Fe,Cu,Mn more or less.