The acclimatization strategies of kidney vetch (Anthyllis vulneraria L.) to Pb toxicity

Abstract

Kidney vetch (Anthyllis vulneraria L.) is a well-known Zn hyperaccumulator. Zn often occurs with Pb in one ore; thus, plants inhabiting waste dumps are exposed not only to Zn but also to Pb toxicity. While the response of kidney vetch to Zn toxicity is relatively well known, the Pb survival strategy of Anthyllis vulneraria has not been the subject of investigations. The aim of presented research was to determine the survival strategy of kidney vetch exposed to high lead concentrations. Shoot explants of a calamine kidney vetch ecotype were placed on agar media containing 0.0, 0.5, 1.0, and 1.5 mM Pb. Morphological, physiological, and biochemical responses, in particular photosynthetic apparatus of plantlets, were examined. The most pronounced changes were observed in plants grown on media supplemented with 1.5 mM Pb after 8 weeks of culture. Increased dry weight and high lead accumulation were observed in roots. Similarly, in shoots, increased dry weight and a decreased number of newly formed shoots were recorded. The accumulation of lead was many times lower in shoots than in roots. In leaf cells’ ultra-structure, looser arrangement of chloroplast thylakoid grana was observed. Despite the decrease in chlorophyll a and carotenoid content, the photosynthetic apparatus remained efficient due to the lack of photoinhibition and increased electron transport rate beyond photosystem II (PSII). For the first time, an acclimatization mechanism based on maintaining the high efficiency of photosynthetic apparatus resulting from increasing of electron transport rate was described.

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

“…Photosynthesis is closely related to the photosynthetic pigment content and its composition. Although pigment reduction under HMs is well documented (Maina and Wang 2015;Chandra and Kang 2016;Piwowarczyk et al 2018), its degradation is much more complex. Therefore, it is difficult to point any one culprit of such state of affairs.…”

“…Considering the factors significantly influencing pigment content in plants growing in their natural habitats, one cannot overlook the fact that the availability of nitrogen in the soil may affect the profiles (Pereira et al 2016;Piwowarczyk et al 2018). As nitrogen is an indispensable macronutrient for formation of efficiently operating photosynthetic machinery (Evans and Poorter 2001), the decrease in chlorophyll content noted by us in CAL and SER ecotypes may be a physiological response to the low content of nitrogen available for plants in calamine and serpentine substrates (Koszelnik-Leszek 2007;Ciarkowska et al 2017).…”

“…The stressful environmental conditions stimulate the formation of reactive oxygen species (ROS) and their inactivation is controlled by various plant enzymatic and non-enzymatic mechanisms to prevent oxidation damage. Many experiments have highlighted the potential role of phenolic metabolites in ROS defense (Maestri et al 2010;Labudda et al 2016;Muszyńska et al 2018a;Piwowarczyk et al 2018). Phenols protect not only from oxidative stress by direct ROS scavenging or modification of lipid membrane fluidity, but might also chelate metal ions and prevent Fenton's reaction.…”

Response of grass pea (Lathyrus sativus L.) photosynthetic apparatus to short-term intensive UV-A:red radiation

“…The leaves were dark-adapted for 25 min. structural photosynthetic parameters were extracted from the recorded curves using the fluorometer producer's software (PEA-Plus) and/or calculated according to Jiang et al (2008) (Table 1-according to Piwowarczyk et al 2018). Gas exchange measurements were carried out with a portable open gas-exchange system (LCpro-SD; ADC BioScientific Ltd UK) with a 6.24 cm 2 cuvette with a mixed Red/Blue LED Light Source Head.…”

Acclimation of the photosynthetic apparatus and alterations in sugar metabolism in response to inoculation with endophytic fungi

“…In the plants, under nonlimiting growth conditions, only a fraction of the incident radiation is fixed into ATP and NADPH; the majority is dissipated as heat (photochemical dissipation) or through nonregulated mechanisms (Baker, 2008). In the latter case, under overwhelmingly high illumination, due to herbicide usage (PSII electron flux inhibitors) or other stress factors, nonregulated energy dissipation is deleterious, causing significant damage to the photosynthetic apparatus (Piwowarczyk et al, 2018;X.-G. Zhu, Long, & Ort, 2010). In the E+ seedlings, the fraction of the light dissipated was significantly lower compared with the control plants.…”