褪黑素对花椒幼苗低温伤害的缓解效应

The Mitigative Effect of Melatonin on Zanthoxylum bungeanum Seedlings under Chilling Stress

以“韩城大红袍”花椒幼苗为试验材料,探究叶面喷施200μmol/L的褪黑素(MT)对4℃下植株的低温缓解效应。结果表明,与未处理植株相比,MT处理可提高低温胁迫下叶绿素荧光参数、过氧化物酶(POD)活性及可溶性糖含量(SS),降低丙二醛(MDA)和活性氧(ROS)含量。转录组分析结果表明,与未处理植株相比,MT处理中差异表达的基因(DEGs)主要富集在光合相关、膜蛋白复合物以及糖代谢通路中。对光合及糖代谢途径进一步分析发现,低温胁迫下,MT处理上调了与光系统Ⅱ相关的Psb基因家族的基因及淀粉合成与分解相关的酶基因。综合分析表明,低温胁迫下花椒幼苗的生长受到抑制,喷施MT可缓解低温胁迫对花椒幼苗的伤害,提高抗寒能力。

Seedlings of Zanthoxylum bungeanum cultivar"Hancheng Dahongpao"were used as the experimental materials to explore the mitigative effect of spraying with 200μmol/L melatonin(MT)on plants at 4℃.The results showed that compared with untreated plants,MT increased chlorophyll fluorescence parameters,peroxidase(POD)activity and soluble sugar content(SS),and reduced the content of malondialdehyde(MDA)and reactive oxygen species(ROS)under chilling stress.The results of transcriptome analysis showed that,compared with untreated plants,differential expression genes(DEGs)in MT treatment were mainly enriched in photosynthesis-related,membrane protein complexes,and glucose metabolism pathways.Further analysis of photosynthesis and sugar metabolism found that the expression of Psb genes family encoding PSⅡand the genes associated with starch synthesis and decomposition were up-regulated in MT treatment under chilling stress.Comprehensive analysis showed that the growth of Z.bungeanum seedlings under chilling stress was restrained.Spraying MT relieved the damage to the seedlings and enhanced the cold tolerance.