中文摘要：

利用大型移动防雨棚开展玉米干旱胁迫及复水试验,通过分析玉米叶片光响应曲线和叶绿素荧光参数,揭示不同生育期干旱胁迫对玉米光合作用和叶绿素荧光的影响程度。结果表明：1）干旱胁迫后玉米净光合速率（Pn）显著降低;当光合有效辐射（PAR）过高时受到强光抑制作用Pn略低,干旱胁迫后受光抑制影响较对照明显;干旱胁迫对玉米光合能力的影响表现为：拔节期〉乳熟期〉苗期;复水10d后光合作用略有恢复,但恢复较缓慢。2）不同发育期受到干旱胁迫后均表现为实际光化学效率（ΦPSⅡ）、光化学淬灭系数（q P）下降,非光化学淬灭系数（q N）升高的趋势,但拔节期叶绿素荧光参数对土壤干旱胁迫的响应比苗期、乳熟期更加敏感,下降和升高幅度更大;复水后,叶绿素荧光参数虽略有恢复,但短期内难以达到正常水平。

英文摘要：

The field experiments of water stress and rewatering for maize were carried out using the large moving water - proof shed. The effect of water stress and rewatering on the photosynthesis and chlorophyll fluorescence characteristics of maize in different growth periods were analyzed via the chlorophyll fluorescence parameters and light response curve of leaves. The results showed as followed ： （ 1 ） After drought stress, the net photosynthesis rate （ Pn ） of maize decreased significantly ; when the photosynthetic radiation （PAR） was the highest, Pn would be slightly lower and obvious than the control with light inhibition. Effect of drought stress on the photosynthetic capacity of maize presented as： jointing stage 〉 milk stage 〉 seedling stage. After 10 days of rewatering, pho- tosynthesis had a slight recovery, but it was so slow. （2） Under drought stress, the actual photochemical efficien- cy（ ФPS Ⅱ）, photochemical quenching coefficient （qP） presented rising trends and the non- photochemical quenching （qN） presented falling trend in each growth stage, but the response of chlorophyll fluorescence param- eters in jointing stage under drought stress was more sensitive than the seedling stage and milk stage, and the de- creasing or increasing ranges was more greater. Although after rewatering, the chlorophyll fluorescence parame- ters had a slight recovery, but it was difficult to reach the normal level in short term.