Melatonin and serotonin are important signaling and stress mitigating molecules that play important roles across growth and development in plants. Despite many well‐documented responses, a systematic investigation of the entire metabolic pathway (tryptophan, tryptamine, and N‐acetylserotonin) does not exist, leaving many open questions. The objective of this study was to determine the responses of Hypericum perforatum (L.) to melatonin, serotonin, and their metabolic precursors. Two well‐characterized germplasm lines (#4 and 112) created by mutation and a haploid breeding program were compared to wild type to identify specific responses. Germplasm line 4 has lower regenerative and photosynthetic capacity than either wild type or line 112, and there are documented significant differences in the chemistry and physiology of lines 4 and 112. Supplementation of the culture media with tryptophan, tryptamine, N‐acetylserotonin, serotonin, or melatonin partially reversed the regenerative recalcitrance and growth impairment of the germplasm lines. Quantification of phytohormones revealed crosstalk between the indoleamines and related phytohormones including cytokinin, salicylic acid, and abscisic acid. We hypothesize that melatonin and serotonin function in coordination with their metabolites in a cascade of phytochemical responses including multiple pathways and phytohormone networks to direct morphogenesis and protect photosynthesis in H. perforatum.

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褪黑素和5-羟色胺：植物形态发生交响乐的调解人

褪黑素和5-羟色胺是重要的信号传导和缓解压力分子，在植物的生长发育中起着重要的作用。尽管有许多有据可查的反应，但不存在对整个代谢途径（色氨酸，色胺和N-乙酰5-羟色胺）的系统研究，这还存在许多悬而未决的问题。这项研究的目的是确定贯叶连翘的反应（L.）褪黑素，5-羟色胺及其代谢前体。将通过突变和单倍体育种程序创建的两个特征明确的种质系（＃4和112）与野生型进行比较，以鉴定特定的反应。种质品系4的再生和光合作用能力均低于野生型或品系112，并且据报道品系4和112的化学和生理学差异显着。色氨酸，色胺，N补充培养基-乙酰5-羟色胺，5-羟色胺或褪黑激素可部分逆转种质系的再生顽固和生长障碍。定量植物激素显示吲哚胺与相关的植物激素（包括细胞分裂素，水杨酸和脱落酸）之间存在串扰。我们假设褪黑素和血清素与它们的代谢产物协同作用，形成一连串的植物化学反应，包括多种途径和植物激素网络，以指导形态发生和保护贯叶连翘的光合作用。