DNA Methylation Correlates With Responses of Experimental Hydrocotyle vulgaris Populations to Different Flood Regimes

Abstract

Epigenetic mechanisms such as DNA methylation are considered as an important pathway responsible for phenotypic responses and rapid acclimation of plants to different environments. To search for empirical evidence that DNA methylation is implicated in stress-responses of non-model species, we exposed genetically uniform, experimental populations of the wetland clonal plant Hydrocotyle vulgaris to two manipulated flood regimes, i.e., semi-submergence vs. submergence, measured phenotypic traits, and quantified different types of DNA methylation using MSAP (methylation-sensitive amplified polymorphism). We found different epi-phenotypes and significant epigenetic differentiation between semi-submerged and submerged populations. Compared to subepiloci (denoting DNA methylation conditions) for the CG-methylated state, unmethylation and CHG-hemimethylation subepiloci types contribute more prominently to the epigenetic structure of experimental populations. Moreover, we detected some epimarker outliers potentially facilitate population divergence between two flood regimes. Some phenotypic variation was associated with flood-induced DNA methylation variation through different types of subepiloci. Our study provides the indication that DNA methylation might be involved in plant responses to environmental variation without altering DNA sequences.

Exploring the crop epigenome: a comparison of DNA methylation profiling techniques

“…DNA methylation has been evaluated in scions of inter-species grafting of Solanaceae ( Wu et al., 2013 ), inter- and intra-species grafting of Cucurbitaceae ( Avramidou et al., 2014 ; Xanthopoulou et al., 2019 ), and heterografts of Hevea brasiliensis ( Uthup et al., 2018 ). MSAP has detected adaptive epigenetic differentiation in mangrove populations grown in contrasting environments ( Lira-Medeiros et al., 2010 ), in Hydrocotyle vulgaris populations under different flooding regimes ( Wang et al., 2022 ), and in grapevine clones or varieties grown in diverse geographical locations ( Xie et al., 2017 ; Baránková et al., 2021 ; Varela et al., 2021 ). It has been utilized to investigate the association of DNA methylation with phenotypic variance in maize ( Zea mays ) ( Xu et al., 2019 ), and in populations of non-model plants, including the perennial herb Scabiosa columbaria ( Groot et al., 2018 ), the ornamental tree Prunus mume ( Ma et al., 2018 ), cork oak ( Quercus suber ) ( Inácio et al., 2017 ) and Vitex negunda ( Lele et al., 2018 ).…”

Does genotypic diversity of Hydrocotyle vulgaris affect CO2 and CH4 fluxes?

“…It is native to Europe and the United States, often inhabiting moist habitats such as rivers, ponds, swamps, valleys, and dune grasslands ( Xue et al., 2022 ). This species can reproduce rapidly by clonal growth and show high morphological plasticity ( Wang et al., 2022 ). Different genotypes of H. vulgaris differ in competitive ability ( Zhang L. et al., 2022 ) and clonal integration ( Si et al., 2020 ).…”

The complete chloroplast genome sequence of Hydrocotyle vulgaris L. (Araliaceae)

“… 2021 ; Wang et al. 2022 ). In the 1990s, H. vulgaris was introduced to China as an ornamental plant, but now it occurs in many natural and semi-natural wetlands and grasslands, such as wetlands of regions south of the Yangtze River (Liu et al.…”