Effects of application of Zn, Fe, and Mo on the alfalfa yield and their contents and absorption amounts

Chinese. 采用随机区组试验设计，研究锌、铁、钼配施对紫花苜蓿（Medicagosativa L．）产草量及锌铁钼含量和吸收量的影响，为其合理施肥提供依据。结果表明：锌、铁、钼以不同比例配施均能提高紫花苜蓿产草量，且单施锌（12kg・hm. 2）、铁（15kg・hm. 2）、钼（0．5kg・hm. 2）或两两配施效果显著（P〈0．05）；尤其是锌（12kg・hm. 2）和钼（0．5kg・hm. 2）配施，产草量最高（7．01t・hm. 2），较对照增产25．40％。锌、铁、钼以不同比例配施对紫花苜蓿锌铁钼含量和吸收量影响不尽相同，锌（12kg・hm. 2）、铁（15kg・hm. 2）、钼（0．5kg・hm. 2）三者互作能显著（P〈0．05）提高苜蓿锌铁钼的含量和锌钼吸收量，钼锌互作能显著（P〈0．05）提高苜蓿钼和锌的含量和吸收量；单施锌或锌铁互作能显著（P〈0．05）提高苜蓿锌的含量和吸收量；单施钼或钼铁互作能显著（P〈0．05）提高苜蓿钼的含量和吸收量；而单施铁或与锌或钼互作均未能显著提高苜蓿铁的含量和吸收量。

English. Alfalfa is a kind of perennial legume forage and its high yield with high quality production require not only N, P, and K fertilizer but also many microelements. However, there are fewer reports on the effects of application Zn, Fe and Mo on alfalfa yield. The soil of pasture area in Henan province mainly belongs to sandy alluvial soils which are short of Zn, Fe, and Mo elements. In order to obtain optimum fertilization practice, an experiment with completed experimental design was conducted to investigate the effects of application Zn, Fe and Mo on alfalfa yield and their contents and absorption amounts in alfalfa. The results show that the combined application of Zn, Fe, and Mo fertilizer increased the dry matter （DM） yields of alfalfa and single application or two combination of Zn （12 kg・hm. 2）, Fe （15 kg・ hm. 2）, and Mo （0.5kg・hm. 2） fertilizer significantly increased the DM yields of alfalfa （P〈0. 05）; especially the combination Of Zn （12 kg・hm. 2） and Mo （0. 5kg・hm. 2） fertilizer resulted highest alfalfa DM yield of 7.01 t・hm. 2 , an increase of 25.40% in comparison with control. The different rations of Zn, Fe, and Mo fertilizer influenced the their contents and absorption amounts in alfalfa, combined application of Zn （12 kg・hm. 2）, Fe （15 kg・ hm. 2）, Mo （0.5kg・hm. 2） fertilizer markedly increased their contents and the absorption amounts of Zn and Mo in alfalfa （P〈0.05） ; combined application of Zn and Mo fertilizer marked- ly increased Zn and Mo＇s contents and absorption amounts in alfalfa （P〈0.05） ; single application of Zn or combined application of Zn and Fe fertilizer markedly （P〈0.05） increased Zn＇s content and absorption amount in alfalfa. Single application of Mo or combined application of Mo and Fe fertilizer markedly in- creased Mo＇s content and absorption amount in alfalfa （P〈0.05）. However, single application of Fe or combined application of Fe and Zn or Mo fertilizer failed to increase Fe＇s content and absorption amount of alfalfa.