镁肥对玉米功能叶光系统Ⅱ荧光特性的影响

Effects of magnesium fertilizer on photosystem Ⅱ chlorophyll fluorescence characteristics of functional leaves in maize

以辽宁地区主栽玉米品种沈玉21号、东单90号为试验材料,通过设置6个不同水平的镁肥用量（A1：0 kg·hm^-2、A2：22.5 kg·hm^-2、A3：45 kg·hm^-2、A4：67.5 kg·hm^-2、A5：90 kg·hm^-2、A6：112.5kg·hm^-2）,测定穗位叶片ABS/RC、ET0/RC、TR0/RC、M0、Sm、φE0等叶绿素荧光参数,研究不同镁肥用量对玉米光系统Ⅱ（photosystemⅡ,PSⅡ）荧光特性的影响.结果表明：与不施镁对照相比,沈玉21号施镁45-67.5 kg·hm^-2,叶片光系统Ⅱ荧光参数值显著或极显著提高,镁肥施用量超过67.5 kg·hm^-2的处理（A5和A6）除对φE0外的所有参数无提高作用,甚至显著地降低;而东单90号施镁67.5-90 kg·hm^-2,叶片光系统Ⅱ荧光参数值显著或极显著提高,镁肥施用量低于67.5 kg·hm^-2的处理对除TR0/RC外的所有参数无提高作用.综上,沈玉21号的镁肥施用量为45-67.5 kg·hm^-2、东单90号的镁肥施用量为67.5-90 kg·hm^-2可以提高光系统Ⅱ的线性电子传递效率,增加光合同化力,提高光能利用效率.

Using maize hybrids Shenyu 21 and Dongdan 90 as entries,the effects of magnesium fertilizer on photosystem Ⅱ（PSⅡ） chlorophyll fluorescence characteristics of maize were studied through measuring chlorophyll fluorescence parameters such as ABS/RC,ET0/RC,TR0/RC,M0,Sm and φE0 in six magnesium fertilizer levels（0,22.5,45,67.5,90,and 112.5 kg·hm^-2）.The results showed that,compared with the control,the chlorophyll fluorescence parameters in Shenyu 21 increased significantly or highly significantly when the magnesium fertilizer amounts ranged from 45 to 67.5 kg·hm^-2.The magnesium fertilizer did not affect or decreased the parameters beside φE0 when the fertilizer level was more than 67.5 kg·hm^-2.As for Dongdan 90,the chlorophyll fluorescence parameters increased significantly or highly significantly at the application amounts of magnesium fertilizer between 67.5 and 90.0 kg·hm^-2,but changed less beside the parameter of TR0/RC when the fertilizer amount was less than 67.5 kg·hm^-2,compared with control.Therefore,the PSⅡ linear electron transfer efficiency could be promoted,and assimilatory ability could be increased,and light utilization efficiency could be enhanced under the magnesium fertilizer levels of 45-67.5 kg·hm^-2 in Shenyu 21 or 67.5-90 kg·hm^-2 in Dongdan 90.