论文部分内容阅读
为探讨根际供水状况与姜叶片需光特性的关系,通过模拟干旱与遮光(50%)交互处理,研究了自然光照正常供水(T1)、遮光正常供水(T2)、自然光照干旱(T3)、遮光干旱(T4)等对姜叶片光合参数及叶绿素荧光参数的影响。结果表明,试验处理过程中,T1、T2姜叶片Pn无显著变化,而T3、T4均持续降低,且降幅以T3较大;随处理时间的延长,T1、T2的Ci及Ls未发生显著变化,而T3、T4分别在胁迫1 d、3 d后,其Ci即升高而Ls降低,表明胁迫初期T3、T4姜叶片Pn的降低主要为气孔限制,而后期则以非气孔限制为主;处理6 d时,尽管各处理姜叶片Pn在午间均显著降低,但降幅以T3、T4较大,尤其T3在午后未出现第二峰值,而T1、T2、T4均表现为双峰曲线变化。试验处理过程中,T1、T3、T4姜叶片Fv/Fm持续降低,NPQ升高,但变幅以T3较大,T4次之,T1较小,T2则无显著变化;处理6d时,虽然各处理姜叶片Fv/Fm、ФPSⅡ、qP均在午间显著降低,NPQ显著升高,但变幅以T3较大,T4、T1次之,T2较小。表明干旱胁迫对姜叶片光化学效率的影响大于自然光照胁迫,而遮光则可缓解干旱胁迫。
In order to explore the relationship between the water supply status of Rhizosphere and the light requirement of ginger leaves, the effects of natural light (T1), normal water supply (T2), natural sunlight (T3) , Light-sheltered drought (T4) on photosynthetic parameters and chlorophyll fluorescence parameters of ginger leaves. The results showed that there was no significant change of Pn in T1 and T2 ginger leaves, while the decrease of T3 and T4 in T3 and T4, and the decrease of T3 was larger in T1 and T2 ginger leaves. The Ci and Ls in T1 and T2 did not change significantly with the extension of treatment time , While Ci and T4 increased at Ci and T4 after 1 and 3 d of stress, respectively, indicating that the reduction of Pn in T3 and T4 ginger leaves was mainly stomatal limitation at the early stage of stress and the non-stomatal limitation at the later stage. At 6 days, although the Pn in leaves of all treatments decreased significantly at midday, the decline was larger at T3 and T4. In particular, T3 did not show the second peak at noon, while T1, T2 and T4 all showed bimodal curves. In the process of treatment, the Fv / Fm of T1, T3 and T4 leaves kept decreasing while the NPQ increased, but the amplitude of T3 was larger, followed by T4, T1 smaller and T2 no significant change. Fv / Fm, ФPSⅡ and qP of ginger leaves decreased significantly at midday and significantly increased at NPQ. However, the amplitude of T3 was larger, T4 and T1 were lower, and T2 was smaller. The results showed that the effect of drought stress on photochemical efficiency of ginger leaves was greater than that of natural light, while light-shading could alleviate the drought stress.