Structural, physiological and genetic diversification of Silene vulgaris ecotypes from heavy metal-contaminated areas and their synchronous in vitro cultivation

Abstract

Main conclusion Results provide significant comparison of leaf anatomy, pigment content, antioxidant response and phenolic profile between individuals from miscellaneous populations and describe unified cultivation protocols for further research on stress biology.The plant communities growing on heavy metal-polluted areas have attracted considerable attention due to their unique ability to tolerate enormous amounts of toxic ions. Three ecotypes of Silene vulgaris representing calamine (CAL), serpentine (SER) and non-metallicolous (NM) populations were evaluated to reveal specific adaptation traits to harsh environment. CAL leaves presented a distinct anatomical pattern compared to leaves of SER and NM plants, pointing to their xeromorphic adaptation. These differences were accompanied by divergent accumulation and composition of photosynthetic pigments as well as antioxidant enzyme activity. In CAL ecotype, the mechanism of reactive oxygen species scavenging is based on the joint action of superoxide dismutase and catalase, but in SER ecotype on superoxide dismutase and guaiacol-type peroxidase. On the contrary, the concentration of phenylpropanoids and flavonols in the ecotypes was unchanged, implying the existence of similar pathways of their synthesis/degradation functioning in CAL and SER populations. The tested specimens showed genetic variation (atpA/MspI marker). Based on diversification of S. vulgaris populations, we focused on the elaboration of similar in vitro conditions for synchronous cultivation of various ecotypes. The most balanced shoot culture growth was obtained on MS medium containing 0.1 mg l −1 NAA and 0.25 mg l −1 BA, while the most abundant callogenesis was observed on MS medium enriched with 0.5 mg l −1 NAA and 5.0 mg l −1 BA. For the first time, unified in vitro protocols were described for metallophytes providing the opportunity to conduct basic and applied research on stress biology and tolerance mechanisms under freely controlled conditions.Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Ecotype-Specific Pathways of Reactive Oxygen Species Deactivation in Facultative Metallophyte Silene vulgaris (Moench) Garcke Treated with Heavy Metals

“…Plant material constituted the in vitro shoot culture of three ecotypes of Silene vulgaris (Moench) Garcke (Caryophyllaceae) that were propagated on the optimized proliferation medium according to the protocol proposed by Muszyńska et al [22]. Two HM-tolerant cultures were obtained earlier from seeds of specimens representing calamine (described further as CAL) and serpentine (SER) populations, while control non-metallicolous (NM) culture originated from seeds collected from an unpolluted stand [9,22]. In the experimental period, apical fragments of shoots (explants) were placed on the proliferation medium enriched simultaneously with zinc, lead, and cadmium salts.…”

“…In the experimental period, apical fragments of shoots (explants) were placed on the proliferation medium enriched simultaneously with zinc, lead, and cadmium salts. In the first treatment, the applied doses of HMs reflected their contents in the natural habitat of the calamine ecotype, i.e., 714.3 µM ZnSO 4 , 3.0 µM Pb(NO 3 ) 2 , and 16.4 µM CdCl 2 (described further as 1× HMs) [22]. In the following, HM concentration was 2.5-and 5.0-times higher than the first one (described further as 2.5× HMs and 5× HMs, respectively).…”

“…One of the facultative metallophytes is the bladder campion (Silene vularis) belonging to the Caryophyllaceae family. Our recent study showed that contrasting ecotypes of this species from two metal-tolerant populations growing on waste heaps deposited after the mining and processing of calamine and serpentine rocks differed significantly in anatomical, physiological, and genetic features, not only from reference specimens occurring in unpolluted areas, but to some extent also to each other [22]. What is more, under fully controlled in vitro conditions, we have ascertained the survival strategy resulting from the ecotype-dependent activation of antioxidant machinery in these three ecotypes treated separately with Pb or Ni ions, i.e., metals which are characteristic for natural habitats of metallicolous populations [9].…”

The improved resistance against gypsy moth in Larix olgensis seedlings exposed to Cd stress association with elemental and chemical defenses

“…Given the fact that soil is the main substrate for plant growth, there is an urgent need to better understand the physiological and ecological response mechanisms of various plants grown in heavy metal contaminated regions. Many studies have addressed absorption, transfer and enrichment characteristics of heavy metals in plants, as well as their detoxification or tolerance mechanisms when exposed to heavy metal stress . However, there are a lot of controversies about how heavy metal stress affects the chemical defense of woody plants against phytophagous insects.…”

“…Many studies have addressed absorption, transfer and enrichment characteristics of heavy metals in plants, as well as their detoxification or tolerance mechanisms when exposed to heavy metal stress. [5][6][7] However, there are a lot of controversies about how heavy metal stress affects the chemical defense of woody plants against phytophagous insects.…”