5-氨基乙酰丙酸和乙烯利对东北春玉米功能叶光合生理特性和产量的影响

以中单909为材料,设置5-氨基乙酰丙酸（5-ALA）和乙烯利（ETH）不同浓度复配组合,于拔节期（V6）进行叶面喷施。研究5-ALA-ETH复配剂对缓解东北春玉米冠层郁闭效应、提高叶片净光合效率（P_n）、增强叶片的光合产物供给能力、保障春玉米稳产增产的调控效应。结果表明,A2E1（22.5g/hm² 5-ALA+450mL/hm² ETH）处理能够增强叶片的光合生理活性,调控效果最佳,其中V7期叶片叶绿素含量相比对照（CK）显著提高8.9%,V12期叶片RuBP羧化酶（RuBPCase）和PEP羧化酶（PEPCase）活性比CK分别显著提高65.2%和87.1%,V8和V12期叶片P_n比CK分别显著提高14.8%和24.5%。同时,该处理提高了叶片蔗糖的合成能力,其中V12期叶片蔗糖合酶（SS）活性比CK显著提高85.0%,V11期蔗糖磷酸合酶（SPS）活性比CK显著提高33.1%,V7、V9和V12期叶片蔗糖含量比CK分别显著提高69.2%、16.8%和78.6%。在玉米收获期,A2E1处理显著增加了玉米穗长、穗粒数和产量,相比CK分别提高了5.4%、6.2%和5.4%,玉米秃尖长显著缩短50.4%。综上所述,5-ALA（22.5g/hm²）和ETH（450mL/hm²）复配能够改善东北春玉米生育期内光合生理特性,提高收获穗粒数和产量,增强其抵抗冠层郁闭效应胁迫的能力。

Effects of 5-Aminolevulinic Acid and Ethephon on Photosynthetic Physiology of Leaves and Yield of Spring Maize in Northeast China

Field experiments were conducted with maize variety Zhongdan 909 aiming to investigate the effect of 5-aminolevulinic acid(5-ALA)and ethephon(ETH)combined solution,spraying at jointing growth stage,on relieving canopy closure stress,improving net photosynthetic efficiency(Pn),enhancing organic supply capacity and ensuring stable and high yield in the Northeast China.The results showed that A2E1(22.5g/hm25-ALA+450mL/hm2 ETH)treatment was better than other treatments and improved maize leaf physiological activity significantly.Under the A2E1 treatment,leaf chlorophyll content at V7 stage,the activities RuBP carboxylase(RuBPCase)and PEP carboxylase(PEPCase)at V12 stage were significantly increased by 8.9%,65.2%and 87.1%,respectively,and the Pn at V8 and V12 stages were 14.8%and 24.5%higher than that of the control at the same growth stage.Meanwhile,leaf sucrose synthase(SS)activity at V12 stage and sucrose phosphate synthase(SPS)activity at V11 stage were increased by 85.0%and 33.1%,respectively.Leaf sucrose contents at V7,V9 and V12 stage were increased by 69.2%,16.8%and 78.6%,respectively.At harvest stage,ear length,kernel number per ear,and yield were increased by 5.4%,6.2%,and 5.4%,respectively,and the bare tip length was shortened by 50.4%.Based on the above results,the 5-ALA and ETH combined solution could improve the physiological activity of maize leaves,increase kernel number per ear,and yield,and thus enhance the resisting canopy closure ability.