夜间补光对小麦叶片激素含量及光合特性的影响

为探究夜间补光对小麦生育后期的调控作用,以冬小麦品种豫农186为材料,以自然光照时间为对照,在小麦抽穗后设置夜间人工补光2h、4h和6h三个处理,研究补光时间对小麦叶片内源激素含量、光合特性及产量的影响。结果表明,夜间补光可增加小麦叶面积及旗叶叶绿素含量和光合速率,以补光6h的效果最显著。与自然对照相比,夜间补光显著增加旗叶GA3、IAA、ZR含量,且激素含量的升高幅度随补光时间的延长而增加,但ABA含量受影响较小。夜间补光能显著提高灌浆前期和中期籽粒灌浆速率及千粒重和产量,其中补光6h处理的最大灌浆速率比自然对照增大16.21%,产量提高14.07%。说明小麦抽穗后适当延长光照时间有利于叶片的生长发育,可提高激素含量和光合效率,促进籽粒灌浆,增加产量。

Effect of Supplemental Illumination at Night on Endogenous Plant Hormones Content and Photosynthetic Characteristics in Wheat Leaves

Using a winter wheat cultivar Yunong 186 as material and natural lighting as control,the effects of supplemental illumination at night on endogenous plant hormones content,photosynthetic characteristics,and grain yield were investigated by additional artificial lighting for 2(T1),4(T2) and 6 h(T3) at night. The results showed that,compared with the control treatment,the treatment of supplemental illumination at night could improve the area of flag leaf,increase the chlorophyll content and photosynthetic rate of flag leaf,and the effect of 6 h treatment(T3) was significant. Compared with natural control,the treatments of supplemental lighting at night significantly increased the content of GA₃,IAA,and ZR,but it had little influence on ABA. Compared with natural control,supplemental lighting time could significantly increase the grain filling rate,grain weight and yield at early and middle stages of grain filling. The maximum filling rate was increased by 16.21%,compared with that of natural control,and the yield of T3 treatment was 14.07% higher than that of natural control.The results indicated that proper supplemental lighting time is beneficial to growth of leaves,which enhanced the content of endogenous plant hormones and photosynthetic characteristics,and achieved more biomass accumulation and higher yield.