30%己乙水剂对玉米根系生理活性的调控效应

Effects of 30% Diethyl-Amino-Ethyle-Hexanoate·Ethephon Aqueous Solution on Physiological Activities of Maize Roots

以玉米品种农大3138为材料，在大田和PVC管栽条件下研究了应用植物生长调节剂30％己乙水剂对玉米根系生理活性的影响。结果表明，玉米6叶期用400mg／L30％己乙水剂叶面喷施处理，可增加根系干重，显著提高第8层根（气生根）量，提高拔节期和籽粒形成期1—4层根、6—7层根的活力；提高拔节期和籽粒形成期1-4层根中蔗糖转化酶活性。^15N示踪试验结果表明，30％己乙水剂处理提高了玉米灌浆期氮的累积，增加了向果穗和根系的分配，提高了根系伤流量和根系中氨基酸含量。30％己乙水剂处理后，玉米根系中生长素、细胞分裂素、赤霉素、脱落酸等激素含量的变化同根系生理活性变化相应，特别是通过根系伤流液向地上部输送细胞分裂素的能力增强，可能是整株生长发育改善的重要原因。30％己乙水剂施用提高玉米产量11．7％。

Roots is a vital part of the maize plant, however few of the research for practically regulating root function has been reported. In this study, the effects of a new mixture formulation of plant growth regulators registered in China, 30% diethyl-amino-ethyle-hexanoate·ethephon aqueous solution （30% DE）, on maize （Zea may L. cv. Nongda3138） were measured and evaluated in the cultivated condition of field and PVP-tubes. The physiological activities of roots were improved by foliage spray of 30%DE at the 6-1eaves-expended stage of maize. The dry weight of roots, especially for the 8th layer of roots, was increased significantly by 30% DE. The roots activities of the 1st-4th and the 7th-8th layers were promoted at silking and filling stage, and the activities of invertase in the 1st - 4th layer roots were higher than that in control. ^15N tracing experiment showed that nitrogen accumulation in the whole plant and the ^15N distribution in ears and roots was enhanced by 30% DE. The volume of root bleeding sap collected from the 1st internode of basal stem the content of total amino acids in bleeding sap were both increased. The contents of plant hormones （auxins, cytokinins, gibberellins and abscisic acid） in maize roots and root bleeding sap were also changed respectively by the foliage treatment of 30% DE. Cytokinins contents in root bleeding sap were increased remarkably, indicating the promoted transport of cytokinins from roots to shoots through xylem by 30% DE. The grain yield was increased by 11.7% and the yield components were also improved. 30% DE was proved to be a practical formulation of plant growth regulator for the improvements in grain productivity and physiological activities of roots mainly through the hormonal system.