弱光胁迫对滴灌玉米叶绿素荧光及生长特性的影响

Effects of Weak Light Stress on Chlorophyll Fluorescence and Growth Characteristics of Drip-Irrigated Maize

以新疆主播品种新玉9号为供试品种,采用人工控光来模拟不同强度的光照条件,在全生育期、抽雄吐丝期、成熟期分别进行20%、50%和70%的遮阴处理,研究不同生育期弱光胁迫下玉米的光合生理机制。研究表明,遮阴处理后,玉米叶片叶绿素相对含量SPAD值显著增加,荧光参数ΦPSII、Fv/Fm和qP升高,NPQ降低,且随着遮阴程度的增加其变化越显著,解除遮阴处理后逐渐恢复至对照(CK)水平。遮阴处理后玉米干物质积累和产量均不同程度减小,全生育期遮阴玉米株高、茎粗、叶面积和产量均显著减小,抽雄吐丝期和成熟期遮阴玉米雌穗变化显著,株高、茎粗和叶面积变化不显著。与CK相比,全生育期遮阴、抽雄吐丝期遮阴和成熟期遮阴对玉米生长发育进程也有明显影响,全生育期遮阴和抽雄吐丝期遮阴延迟玉米生育进程,成熟期遮阴提前玉米生育进程。

Xinjiang main breed variety Xinyu No.9 was used as the tested variety,Artificial light control was used to simulate the light conditions of different intensities,and 20%,50%,and 70%shading treatments were carried out in the whole growth period,the silking stage and the maturity stage respectively,and the photosynthesis of maize under weak light stress in different growth stages was described.Physiological mechanism.The results showed that after shading treatment,the chlorophyll relative SPAD value of maize leaves increased significantly,the fluorescence parametersΦPSII,Fv/Fm and qP increased,NPQ decreased,and the change was more significant with the increase of shading degree.After treatment,it gradually returned to the control(CK)level.After shading treatment,the dry matter accumulation and yield of maize were reduced to different extents.The plant height,stem diameter,leaf area,and yield of shaved maize in the whole growth period were significantly reduced,and the changes of maize ears during shaving and maturity were observed.Significantly,plant height,stem diameter and leaf area did not change significantly.Compared with CK,shading during the whole growth period,shading at silking stage,and shading at maturity also have a significant impact on the growth and development of maize.The shading period during the whole growth period and the shaving period of the males delay the growth of maize,mature stage.The shade has advanced the maize growth process.