Effect of Pb ions on superoxide dismutase and catalase activities in leaves of pea plants grown in high and low irradiance

Makowski

et al. 2020

IJMS

Ceylon leadwort (Plumbago zeylanica) is ornamental plant known for its pharmacological properties arising from the abundant production of various secondary metabolites. It often grows in lead polluted areas. The aim of presented study was to evaluate the survival strategy of P. zeylanica to lead toxicity via photosynthetic apparatus acclimatization. Shoots of P. zeylanica were cultivated on media with different Pb concentrations (0.0, 0.05, and 0.1 g Pb∙l−1). After a four-week culture, the efficiency of the photosynthetic apparatus of plants was evaluated by Chl a fluorescence measurement, photosynthetic pigment, and Lhcb1, PsbA, PsbO, and RuBisCo protein accumulation, antioxidant enzymes activity, and chloroplast ultrastructure observation. Plants from lower Pb concentration revealed no changes in photosynthetic pigments content and light-harvesting complex (LHCII) size, as well as no limitation on the donor side of Photosystem II Reaction Centre (PSII RC). However, the activity and content of antioxidant enzymes indicated a high risk of limitation on the acceptor side of Photosystem I. In turn, plants from 0.1 g Pb∙l−1 showed a significant decrease in pigments content, LHCII size, the amount of active PSII RC, oxygen-evolving complex activity, and significant remodeling of chloroplast ultrastructure indicated limitation of PSII RC donor side. Obtained results indicate that P. zeylanica plants acclimate to lead toxicity by Pb accumulation in roots and, depending on Pb concentration, by adjusting their photosynthetic apparatus via the activation of alternative (cyclic and pseudocyclic) electron transport pathways.

Section: Discussionmentioning

confidence: 60%

Can Ceylon Leadwort (Plumbago zeylanica L.) Acclimate to Lead Toxicity?—Studies of Photosynthetic Apparatus Efficiency

Makowski

et al. 2020

IJMS

“…We previously observed [14] that Pb ions stimulated the respiration rate in pea leaves in plants grown in high light conditions, which was accompanied by an increase in ATP production in mitochondria. We also found that the inhibition of photosynthesis by Pb ions was higher in low-than in high-light-grown plants as a consequence of decreasing electron transport in the photosynthesis light reaction [68]. Lead is absorbed by plants mainly through the root system and in minor amounts through the leaves.…”

Section: Discussionmentioning

confidence: 72%

Lead-Induced Changes in Fluorescence and Spectral Characteristics of Pea Leaves

2019

Chlorophyll fluorescence parameters can provide useful indications of photosynthetic performance in vivo. Coupling appropriate fluorescence measurements with other noninvasive techniques, such as absorption spectroscopy or gas exchange, can provide insights into the limitations to photosynthesis under given conditions. Chlorophyll content is one of the dominant factors influencing the conditions of a vegetation growing season, and can be tested using both fluorescence and remote sensing methods. Hyperspectral remote sensing and recording the narrow range of the spectrum can be used to accurately analyze the parameters and properties of plants. The aim of this study was to analyze the influence of lead ions (Pb, 5 mM Pb(NO3)2) on the growth of pea plants using spectral properties. Hyperspectral remote sensing and chlorophyll fluorescence measurements were used to assess the physiological state of plants seedlings treated by lead ions during the experiment. The plants were growing in hydroponic cultures supplemented with Pb ions under various conditions (control, complete Knop + phosphorus (+P); complete Knop + phosphorus (+P) + Pb; Knop (-P) + Pb, distilled water + Pb) affecting lead uptake via the root system. Spectrometric measurements allowed us to calculate the remote sensing indices of vegetation, which were compared with chlorophyll and carotenoids content and fluorescence parameters. The lead contents in the leaves, roots, and stems were also analyzed. Spectral characteristics and vegetation properties were analyzed using statistical tests. We conclude that: (1) pea seedlings grown in complete Knop (with P) and in the presence of Pb ions were spectrally similar to the control plants because lead was not transported to the shoots of plants; (2) lead most influenced plants that were grown in water, according to the highest lead content in the leaves; and (3) the effects of lead on plant growth were confirmed by remote sensing indices, whereas fluorescence parameters identified physiological changes induced by Pb ions in the plants.

“…Effect of Cd on C. comosum growth As a non-essential and toxic heavy metal element for plants, Cd can affect mitosis in plant cells, slow the rate of cell division, and influence plant growth by affecting physiological and biochemical processes (Romanowska et al 2008;Seregin and Kozhevnikova 2006). The root system is the main part that absorbs and excludes heavy metals; the root length of sensitive plants are obviously inhibited under heavy metal force while the growth of roots are affected slightly in tolerant plants, so TI is an important indicator that reflects the heavy metal tolerance of plants (Yan et al 1997(Yan et al , 2009.…”

Section: Resultsmentioning

confidence: 99%

Accumulation and tolerance characteristics of cadmium in Chlorophytum comosum: a popular ornamental plant and potential Cd hyperaccumulator

Wang

Yan

Dai

et al. 2011

Environ Monit Assess

The effects on the growth, physiological indexes and the cadmium (Cd) accumulation in Chlorophytum comosum under Cd stress were examined by pot-planting. The results showed that the tolerance index (TI) of C. comosum were all above 100 in soil Cd concentration of 100 mg kg(-1). The O(2˙)⁻ production rate and electrical conductivity of C. comosum were significantly positively correlated to Cd adding-concentration while the MDA content increased and had significant differences with the control. The activities of SOD, CAT, and POD all rose significantly in lower Cd concentration and the Cd threshold of them were around 10, 50 and 20 mg kg(-1), respectively. The Cd in C. comosum root and aboveground part reached 1,522 and 865·5 mg kg(-1), respectively, in Cd concentration of soil up to 200 mg kg(-1). For the advantages of high tolerance, high accumulation, and high ornamental value, C. comosum may have tremendous application value in the treatment of Cd-contaminated soils.