Poplar hybrids can be used for selenium (Se) and boron (B) phytoremediation under saline conditions. The phenolic antioxidant stress response of two salt and B tolerant poplar hybrids of parentage Populus trichocarpa × nigra × deltoides was studied using high-performance liquid chromatography (HPLC) and absorption-based assays to determine the antioxidant capacity, total phenolic content, hydroxycinnamic acid levels, and the enzyme activity of l-phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), phenol peroxidase (POD), and laccase. Most remarkable was the contrasting response of the two poplar clones for PPO activity and phenolic levels to irrigation with high salt/B water. To cope with stressful growing conditions, only one clone increased its phenolic antioxidant level, and each clone displayed different PPO isoform patterns. Our study shows that poplar hybrids of the same parentage can differ in their salt/B stress coping mechanism.

中文翻译：

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高盐和硼灌溉对两种杨树杂种无性系酚类抗氧化剂水平和多酚氧化酶活性的影响

杨树杂种可用于在盐分条件下进行硒（Se）和硼（B）的植物修复。使用高效液相色谱（HPLC）和基​​于吸收的测定方法研究了两个盐和B耐性杨木杨（Populus trichocarpa × nigra × deltoides）的耐盐和B杂种杨树杂种的酚抗氧化应激反应，以确定抗氧化能力，总酚含量，羟基肉桂酸水平，和l的酶活性-苯丙氨酸氨裂合酶（PAL），多酚氧化酶（PPO），苯酚过氧化物酶（POD）和漆酶。最引人注目的是两个杨树无性系对PPO活性和酚水平的反差响应，以高盐/ B水灌溉。为了应对紧张的生长条件，只有一个克隆增加了其酚类抗氧化剂的水平，并且每个克隆都显示出不同的PPO亚型。我们的研究表明，同一亲本的杨树杂种的盐/ B胁迫应对机制可能不同。