褪黑素预处理对桃耐涝性的调控效应

Regulation effect of melatonin pretreatment on waterlogging tolerance in peach seedling

为探究褪黑素对桃耐涝性的调控效应,用200μmol·L^(-1)褪黑素对桃苗进行预处理,再经涝害处理,通过生理指标与转录组分析褪黑素和涝害对桃的影响。结果表明,涝害胁迫下外源褪黑素能保护细胞膜和根系。褪黑素能激活微管形态建成、氧化还原酶活性和蛋白结合相关的基因,巩固根系骨架,激活抗氧化酶活性,提高抗逆性。涝害诱导ERF转录因子家族成员大量表达,通过HRPE和GCC-box顺式作用元件激活下游ADH、ALD、GAPD等糖酵解途径关键酶基因的表达,为低氧胁迫下的植株供能。ERFⅦ成员Prupe.8G264900可能是桃响应涝害的关键基因。

In order to explore the regulation effect of melatonin on waterlogging tolerance in peach,peach seedlings were pretreated with 200μmol·L^(-1)melatonin and then subjected to waterlogging treatment.Physiological indexes and transcriptome sequencing were used to study the effects of melatonin on peach under waterlogging.The results showed that exogenous melatonin slowed chlorophyll degradation and protected cell membranes and roots of peach seedling.Melatonin activated microtubule morphogenesis,REDOX enzyme activity and protein-binding related genes,thus consolidated root skeleton,activated antioxidant enzyme activity and improved stress tolerance.Waterlogging induced abundant expression of ERF transcription factor family members to regulate stress response.All the VII group members of ERF family were significant differential expressed in the waterlogging response group,which could be the key member in hypoxia stress response reaction.In addition,ERF transcription factor activated the activity of key enzymes genes as ADH,ALD,GAPD in glycolysis pathway through HRPE or GCC-box cis-acting elements,which provided energy for plants under hypoxic stress.Prupe.8G264900,a member of ERFⅦ,might be a key gene in response to waterlogging in peach.