Adams S.R., Pearson S., Hadley P. (1997): An analysis of the effects of temperature and light integral on the vegetative growth of pansy cv. universal violet (Viola × wittrockiana Gams.). Annals of Botany, 79: 219–225.
https://doi.org/10.1006/anbo.1996.0347
Baker A.J.M., McGrath S.P., Reeves R.D., Smith J.A.C. (2000): Metal hyperaccumulator plants: a review of the ecology and physiology of a biological resource for phytoremediation of metal polluted soils. In: Terry N., Bañuelos G. (eds.): Phytoremediation of Contaminated Soil and Water. Boca Raton, CRC Press, 85–107. ISBN 9780367399436
Banásová V., Horak O., Čiamporová M., Nadubinská M., Lichtscheidl I. (2006): The vegetation of metalliferous and non-metalliferous grasslands in two former mine regions in Central Slovakia. Biologia, 61: 433–439.
https://doi.org/10.2478/s11756-006-0073-1
Bothe H., Słomka A. (2017): Divergent biology of facultative heavy metal plants. Journal of Plant Physiology, 219: 45–61.
https://doi.org/10.1016/j.jplph.2017.08.014
Dalbato A.L., Kobza F., Suchánková P. (2005): Polyploidy effects on frost tolerance and winter survival of garden pansy genotypes. Horticultural Science, 32: 138–146.
Dalbato A.L., Kobza F., Karlsson L.M. (2013): Effect of polyploidy and pollination methods on capsule and seed set of pansies (Viola × wittrockiana Gams). Horticultural Science, 40: 22–30.
https://doi.org/10.17221/51/2012-HORTSCI
Du X.H., Wang M.G., Słomka A., Liu H.C. (2018): Karyologic and heterosis studies of the artificial inter- and intraspecific hybrids of Viola × wittrockiana and Viola cornuta. HortScience: a publication of the American Society for Horticultural Science, 53: 1300–1305.
https://doi.org/10.21273/HORTSCI13098-18
Ernst W.H.O. (2006): Evolution of metal tolerance in higher plants. Forest Snow and Landscape Research, 80: 251–274.
Fernandes L., Casal S., Pereira J.A., Saraiva J.A., Ramalhosa E. (2017): Edible flowers: a review of the nutritional, antioxidant, antimicrobial properties and effects on human health. Journal of Food Composition and Analysis, 60: 38–50.
https://doi.org/10.1016/j.jfca.2017.03.017
Gao J., Luo M., Zhu Y., He Y., Wang Q., Zhang C. (2015): Transcriptome sequencing and differential gene expression analysis in Viola yedoensis Makino (Fam. Violaceae) responsive to cadmium (Cd) pollution. Biochemical and Biophysical Research Communications, 459: 60–65.
https://doi.org/10.1016/j.bbrc.2015.02.066
Ho J.R., Ma H.W., Wang Y.C., Ko C.H., Chang F.C., Feng F.L., Wang Y.N. (2014): Extraction of heavy metals from contaminated soil by Cinnamomum camphora. Ecotoxicology, 23: 1987–1995.
https://doi.org/10.1007/s10646-014-1326-3
Kuta E., Bohdanowicz J., Słomka A., Pilarska M., Bothe H. (2012): Floral structure and pollen morphology of two zinc violets (Viola lutea ssp. calaminaria and V. lutea ssp. westfalica) indicate their taxonomic affinity to Viola lutea. Plant Systematics and Evolution, 298: 445–455.
https://doi.org/10.1007/s00606-011-0557-5
Kuta E., Jędrzejczyk-Korycińska M., Cieślak E., Rostański A., Szczepaniak M., Migdałek G., Wąsowicz P., Suda J., Combik M., Słomka A. (2014): Morphological versus genetic diversity of Viola reichenbachiana and V. riviniana (sect. Viola, Violaceae) from soils differing in heavy metal content. Plant Biology, 16: 924–934.
https://doi.org/10.1111/plb.12143
Kroon G.H. (1972): Some aspects of the pollination mechanism of Viola tricolor L. and Viola × wittrockiana Gams. Acta Botanica Neerlandica, 21: 630–632.
https://doi.org/10.1111/j.1438-8677.1972.tb00222.x
Kwiatkowska M., Żabicka J., Migdałek G., Żabicki P., Cubała M., Bohdanowicz J., Słomka A., Jędrzejczyk-Korycińska M., Sliwinska E., Sychta K., Marcussen T., Thiele K., Kuta E. (2019): Comprehensive characteristics and genetic diversity of the endemic Australian Viola banksii (section Erpetion, Violaceae). Australian Journal of Botany, 67: 81–98.
https://doi.org/10.1071/BT18233
Li M.S., Luo Y.P., Su Z.Y. (2007): Heavy metal concentrations in soils and plant accumulation in a restored manganese mineland in Guangxi, South China. Environmental Pollution, 147: 168–175.
https://doi.org/10.1016/j.envpol.2006.08.006
Liu J.N., Zhou Q.X., Sun T., Ma L.Q., Wang S. (2008): Identification and chemical enhancement of two ornamental plants for phytoremediation. Bulletin of Environmental Contamination and Toxicology, 80: 260–265.
https://doi.org/10.1007/s00128-008-9357-1
Migdałek G., Woźniak M., Słomka A., Godzik B., Jędrzejczyk-Korycińska M., Rostański A., Bothe H., Kuta E. (2013): Morphological differences between violets growing at heavy metal polluted and non-polluted sites. Flora – Morphology, Distribution, Functional Ecology of Plants, 208: 87–96.
https://doi.org/10.1016/j.flora.2013.02.001
Peng Z., Guo Z.H., Cao X., Xiao X.Y., Liu Y., Shi L. (2018): Phytostabilization potential of ornamental plants grown in soil contaminated with cadmium. International Journal of Phytoremediation, 20: 311–320.
https://doi.org/10.1080/15226514.2017.1381939
Psaras G.K., Constantinidis T. (2009): Two new nickel hyperaccumulators from the Greek serpentine flora. Fresenius Environmental Bulletin, 18: 798–803.
Reboredo F.H., Pelica J., Lidon F.C., Ramalho J.C., Pessoa M.F., Calvão T., Simões M., Guerra M. (2018): Heavy metal content of edible plants collected close to an area of intense mining activity (southern Portugal). Environmental Monitoring and Assessment, 190: 484.
https://doi.org/10.1007/s10661-018-6844-7
Reeves R.D., Baker A.J.M., Jaffré T., Erskine P.D., Echevarria G., van der Ent A. (2017): A global database for plants that hyperaccumulate metal and metalloid trace elements. New Phytologist, 218: 407–411.
https://doi.org/10.1111/nph.14907
Shumaker K., Begonia G. (2005): Heavy metal uptake, translocation, and bioaccumulation studies of Triticum aestivum cultivated in contaminated dredged materials. International Journal of Environmental Research and Public Health, 2: 293–298.
https://doi.org/10.3390/ijerph2005020013
Singh R.J. (2003): Plant Cytogenetics. Boca Raton, CRC Press. ISBN: 0-8493-2388-6
Słomka A., Libik-Konieczny M., Kuta E., Miszalski Z. (2008): Metalliferous and non-metalliferous populations of Viola tricolor represent similar mode of antioxidative response. Journal of Plant Physiology, 165: 1610–1619.
https://doi.org/10.1016/j.jplph.2007.11.004
Słomka A., Kuta E., Szarek-Łukaszewska G., Godzik B., Kapusta P., Tylko G., Bothe H. (2011): Violets of the section Melanium, their colonization by arbuscular mycorrhizal fungi and their occurrence on heavy metal heaps. Journal of Plant Physiology, 168: 1191–1199.
https://doi.org/10.1016/j.jplph.2011.01.033
Słomka A., Kwiatkowska M., Jędrzejczyk-Korycińska M., Bohdanowicz J., Poznańska P., Shuka L., Borucki W., Kuta E. (2017): Insight into "serpentine syndrome" of Albanian, endemic violets (Viola L., Melanium Ging. section) – Looking for unique, adaptive microstructural floral, and embryological characters. Plant Biosystems – An International Journal Dealing with all Aspects of Plant Biology, 151: 1022–1034.
https://doi.org/10.1080/11263504.2016.1219418
Sychta K., Słomka A., Suski S., Fiedor E., Gregoraszczuk E., Kuta E. (2018): Suspended cells of metallicolous and nonmetallicolous
Viola species tolerate, accumulate and detoxify zinc and lead. Plant Physiology and Biochemistry, 132: 666–674.
Sychta K., Słomka A., Sliwinska E., Migdałek G., Kuta E. (2020): From cells highly tolerant to Zn and Pb to fully fertile plants – Selection of tolerant lines with in vitro culture. Plant Physiology and Biochemistry, 146: 231–237.
https://doi.org/10.1016/j.plaphy.2019.11.024
Tangahu B.V., Abdullah S.R.S., Basri H., Idris M., Anuar N., Mukhlisin M. (2011): A review on heavy metals (As, Pb, and Hg) uptake by plants through phytoremediation. International Journal of Chemical Engineering, 939161.
https://doi.org/10.1155/2011/939161
Van der Ent A., Baker A.J.M., Reeves R.D., Pollard A.J., Schat H. (2013): Hyperaccumulators of metal and metalloid trace elements: facts and fiction. Plant and Soil, 362: 319–334.
https://doi.org/10.1007/s11104-012-1287-3
Wierzbicka M., Rostański A. (2002): Microevolutionary changes in ecotypes of calamine waste heap vegetation near Olkusz, Poland:
a review. Acta Biologica Cracoviensia. Series Botanica, 44: 7–19.
Wittrock V.B. (1895): Viola-Studier – A contribution to the history of the pansies having special reference to their origin. Acta Horti Bergiani, 2: 441–522.
Wu F.Z., Yang W.Q., Zhang J., Zhou L.Q. (2011): Growth responses and metal accumulation in an ornamental plant (Osmanthus fragrans var. thunbergii) submitted to different Cd levels. International Scholarly Research Notices, 738138.