1993～1994年冬小麦管栽水分试验结果表明,初生根与次生根生长量、数量及分枝能力基本与土体水量呈正相关,胁迫程度愈深,受抑程度愈大。初生根特别是一、二次根及其分枝数具有很强抗逆能力,水量愈大,三、四次根数愈多。次生根尤其是其数量对土水环境极为敏感,当土壤含水量低于田间持水量60％时,受到严重抑制。胁迫后复水,使初生根三次根数量增加,根系活性延长,对次生根的激励作用更大。前期胁迫愈严重,促进效果愈明显。初生根细长,一直发挥着重要功能,冬前根系功能主要由它完成。次生根粗短,数量大,需消耗较多物质和能量,通过促根实现增产应慎重。起身到抽穗阶段,特别是孕穗期为水分对根系调控效果最佳时期,田间持水量60％可视为调控下限。 The test results of winter wheat tube watering from 1993 to 1994 showed that the growth, quantity and branching ability of primary and secondary root were positively correlated with soil water content. The deeper the degree of stress was, the greater the degree of inhibition was. Primary root, especially the primary and secondary roots and their branches have a strong resilience, the greater the amount of water, the more the number of three or four times. Secondary roots, especially their quantity, are extremely sensitive to the soil and water environment, and are severely inhibited when the soil moisture content is lower than 60% of the field capacity. After rewatering, the number of the third root of the primary root increased, the root activity prolonged, and the secondary root stimulation was more effective. The more severe pre-stress, promote the more obvious effect. Primary root slender, has been playing an important function, root function before winter is mainly done by it. Secondary root stubby, large number, need to consume more material and energy, by promoting root production should be cautious. Up to the heading stage, especially the booting stage for the root regulation of water the best period of 60% field capacity can be regarded as the lower limit of regulation.