A source-sink model explains the difference in the metabolic mechanism of mechanical damage to young and senescing leaves in Catharanthus roseus

Abstract

Background Mechanical damage is an unavoidable threat to the growth and survival of plants. Although a wound to senescing (lower) leaves improves plant vitality, a wound to younger (upper) leaves often causes damage to or death of the whole plant. Source-sink models are often used to explain how plants respond to biotic or abiotic stresses. In this study, a source-sink model was used to explain the difference in the metabolic mechanism of mechanical damage to young and senescing leaves of Catharanthus roseus. Results In our study, GC-MS and LC-QTOF-MS metabolomics techniques were used to explore the differences in source-sink allocation and metabolic regulation in different organs of Catharanthus roseus after mechanical damage to the upper/lower leaves (WUL/WLL). Compared with that of the control group, the energy supplies of the WUL and WLL groups were increased and delivered to the secondary metabolic pathway through the TCA cycle. The two treatment groups adopted different secondary metabolic response strategies. The WLL group increased the input to the defense response after damage by increasing the accumulation of phenolics. A source-sink model was applied to the defensive responses to local (damaged leaves) and systemic (whole plant) damage. In the WUL group, the number of sinks increased due to damage to young leaves, and the tolerance response was emphasized. Conclusion The accumulation of primary and secondary metabolites was significantly different between the two mechanical damage treatments. Catharanthus roseus uses different trade-offs between tolerance (repair) and defense to respond to mechanical damage. Repairing damage and chemical defenses are thought to be more energetically expensive than growth development, confirming the trade-offs and allocation of resources seen in this source-sink model.

Metabolic differences of two constructive species in saline-alkali grassland in China

“…Our GC-MS results showed that gallic acid, vanillic acid, protocatechuic acid, and catechol, acids subordinated to phenolic compounds, were obviously accumulated. These compounds are secondary metabolites that originate from phenylalanine metabolism [ 42 – 44 ]. Gallic acid and protocatechuic acid are the precursors of tannins, which can affect plant thickness and reduce water evaporation [ 20 ].…”

“…Phenolic compound detection was performed as previously described [ 42 ]. After treatment with liquid nitrogen, a 1.0 g pulverized sample was dissolved in 20 mL methanol for extraction and ultrasonicated at low frequency for 40 min.…”

Metabolic Differences Between Suaeda Salsa and Puccinellia Tenuiflora Under Saline-alkali Stress

“…Our GC-MS results showed that gallic acid, vanillic acid, protocatechuic acid, and catechol, acids subordinated to phenolic compounds, were obviously accumulated. These compounds are secondary metabolites that originate from phenylalanine metabolism [20,42,43]. Gallic acid and protocatechuic acid are the precursors of tannin, which can affect plant thickness and reduce water evaporation [19].…”

“…Phenolic compound detection was performed as previously described [20]. After treatment with liquid nitrogen, 1.0 g pulverized sample was dissolved in 20 mL methanol for extraction and ultrasonicated at low-frequency for 40 min.…”

Ionomic and Metabolomic Analyses Reveal Different Response Mechanisms to Saline–Alkali Stress Between Suaeda salsa Community and Puccinellia tenuiflora Community

“…The detection of phenolic compounds was conducted as previously described ( Chen et al, 2021 ). Briefly, 1.0 g of liquid nitrogen pulverized sample was weighed and dissolved in 20 mL of methanol for extraction.…”