Abstract: It is very important for the drought cultivation and root management to carry out the study of response and adaptation mechanism of root growth and physiological characteristics of oats (Avena sativa L.) on drought stress and rehydration in the early growth period. A pot experiment with drought stress and rehydration treatments in oat early growth period was set up to investigate the change of root growth,physiological characteristics and grain yield of oats. The results showed that short-term (14 d) moderate drought stress promoted the root growth indexes and vitality,and severe drought stress showed a continuous inhibition effect on these root indexes. The root MDA content,proline content and antioxidant enzyme activity increased with the severity of drought stress. Rehydration increased the total root length,total root surface area,average root diameter,root dry weight and root vitality which were inhibited by drought stress;also decreases root MDA content,proline content,and SOD and CAT activities that were increased by drought stress. It was concluded that oats could control the root growth and physiological characteristics to adapt drought stress in the early growth period. Some root growth and physiological characteristics affected by drought stress were recovered or compensated because of rehydration. Rehydration reduced the inhibition effect of continuous drought stress on oats grain yield.

Key words: Oats, Drought stress, Rehydration, Growth characteristics of root, Physiological characteristics of root, Yield

摘要： 为研究燕麦（Avena sativa L.）生长早期根系生长和生理特性对干旱胁迫及复水的响应规律和适应机制，本试验采用盆栽控水，测定了干旱胁迫及复水下燕麦生长早期根系生长、生理特性指标及籽粒产量变化。结果表明：短期（14 d）中度干旱胁迫对根系生长指标及活力有促进作用，重度干旱胁迫持续抑制此类根系指标；根系丙二醛（Malondialdehyde，MDA）和脯氨酸含量及抗氧化酶活性随干旱胁迫程度加重而提高；复水使受干旱胁迫抑制的根系总长、根系总表面积、根系平均直径、根系干重和根系活力提高，使受干旱胁迫提高的根系MDA和脯氨酸含量及超氧化物歧化酶（Superoxide Dismutase，SOD）和过氧化氢酶（Catalase，CAT）活性降低。本研究表明燕麦生长早期通过调控根系生长和生理特性适应干旱胁迫，复水使受干旱胁迫影响的燕麦生长早期部分根系生长和生理特性指标得到补偿或恢复，减轻持续干旱胁迫对燕麦籽粒产量的影响。

关键词: 燕麦, 干旱胁迫, 复水, 根系生长特性, 根系生理特性, 产量