| 摘要: |
| 【目的】研究局部水分胁迫对玉米根系导水率的影响，为局部灌溉在农业生产中的利用提供理论依据。【方法】采用分根法对奥玉3007玉米进行水培试验，设4个水分胁迫处理 (渗透势分别为0（CK），－0.2，－0.4，－0.6 MPa)，在所有根系经受6 d水分胁迫后，对一侧根系恢复正常水分供应，对另一侧根系持续进行水分胁迫，用压力室法测定处理0，6，12，24，72，120，168，216 h后两侧根系的导水率。【结果】水分胁迫越严重，玉米的根系导水率越低。经受水分胁迫后再恢复正常水分供应的玉米根系导水率12 h后出现了明显的增长，且始终明显大于持续水分胁迫处理。经水分胁迫再恢复正常水分供应的玉米根系导水率的增幅，与水分胁迫强度呈负相关，与恢复水分供应时间呈正相关。【结论】轻度水分胁迫处理后对局部根系恢复正常水分供应，可明显刺激根系产生水分传导的补偿效应，且这种补偿效应的大小与水分胁迫强度呈负相关。 |
| 关键词: 局部水分胁迫 根系导水率 补偿效应 玉米 |
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| 基金项目:国家自然科学基金项目（51079124）；中央高校基本科研业务费专项（QN2011067）；留学人员科技活动择优资助项目 |
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| Effects of partial water stress on root hydraulic conductivity of maize |
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LI Rui,HU Tian-tian,NIU Xiao-li,et al
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| Abstract: |
| 【Objective】The effects of partial water stress on root hydraulic conductivity of maize were studied.【Method】Aoyu 3007 maize was prepared using split-root and water culture technique.All roots were treated with water stress for 6 d before half roots were treated with normal water level while half roots were treated with water stress persistently.Root hydraulic conductivities with 4 water stress levels (0(CK),－0.2,－0.4,and －0.6 MPa) at different hours after treatment (0,6,12,24,72,120,168,and 216 h) were measured using pressure chamber method.【Result】The increase of water stress led to decrease of root hydraulic conductivity.The hydraulic conductivities of roots treated with normal water level increased significantly after 12 h,and were consistently higher than that of roots treated with persistent water stress.After water stress and recovery,increase of root hydraulic conductivities was negatively correlated with water stress intensity while it was positively correlated with the duration of water recovery.【Conclusion】Compensation effects of root hydraulic conductivity were enhanced after moderate water stress and partial water recovery,and the effects were negatively related with water stress intensity. |
| Key words: partial water stress root hydraulic conductivity compensation effects maize |
