尿囊素对玉米幼苗根系生长及伤流液的影响

用尿囊素（Allantoin，All.）300mg/L和700mg/L喷淋一叶一心期的玉米超甜20号）幼苗，到四叶一心期对根系形态和伤流液进行测定。结果表明，尿囊素使一级根根数、最长根根长、根鲜重和根体积都比对照显著增加，整个根系显得强壮发达。同时，伤流液的流量、电导率、游离氨基酸总量及脯氨酸含量均明显高于对照，从而证明尿囊素确实促进了玉米幼苗根系的生长和对水分、矿质的吸收与同化能力，且尿囊素700mg/L的作用更优于300mg/L。

Effects of allantoin on the root growth and bleeding liquid of maize seedlings

Allantoin (All ) at 300 mg/L or 700 mg/L were sprayed on the maize (super sweet corn No 20) seedlings with a center leaf and a functional leaf and the effects of allantoin on the root morpha and root bleeding liquid were studied when the seedlings had a center leaf and four functional leaves The results showed that the primary root number,the longest root length, root fresh weight and root volume from the roots treated with All. increased obviously than that of the control The root system was very strong and well developed At the same time, the flow, conductance ratio, total free amino acid and free proline content of the root bleeding liquid increased obviously than that of the control These results showed that All really promoted the root growth, and enhanced the abilities of absorption and assimilation for water and minerals The effects of All. at 700 mg/L was better than that of at All.at 300 mg/L