Journal of Environmental Radioactivity 218 (2020) 106256 Available online 7 April 2020 0265-931X/© 2020 Elsevier Ltd. All rights reserved. Disorders of the initial ontogenesis of seed progeny of the common reed (Phragmites australis) from water bodies within the Chernobyl Exclusion Zone A.A. Iavniuk a, * , N.L. Shevtsova b , D.I. Gudkov b a Department of Ecology, Faculty of Environmental Safety, Engineering and Technologies, National Aviation University, Kosmonavta Komarova Ave. 1, UA-03058, Kyiv, Ukraine b Department of Aquatic Radioecology, Institute of Hydrobiology, Geroyev Stalingrada Ave. 12, UA-04210, Kyiv, Ukraine A R T I C L E INFO Keywords: Radioactive contamination Common reed (Phragmites australis) Seeds Dormancy Vitality indices ABSTRACT The peculiarity of seeds germination of the common reed Phragmites australis, which is a cosmopolitan plant and widespread at littoral zone of the Chernobyl Exclusion Zone water bodies, was studied. The complex of vitality, physiological and morphological indices of seedling as seed germination, germination energy, seedling surviv- ability and seed vitality, length of initial leaf and root and abnormalities of seedlings were investigated. The current average absorbed dose rate on the reed vegetative plants ranged from 0.05 to 34 μGy h 1 . Data demonstrated correlation between dose rate and seed progeny vitality. All investigated indices of the common reed’s progeny from impacted water bodies signifcantly differed from reference ones – viability indices were decreased, seedling growth was slower and number of seedling abnormalities were increased. Logistic re- gressions were found for growth of seedlings initial root and leaf from impacted sites and mostly exponential and linear for reference ones. An essential abnormalities percentage up to 75% was registered for reed seedlings from the impacted sites. Signifcance of dormancy for improvement of reed seeds germination from the Chernobyl Exclusion Zone was discussed. 1. Introduction 1.1. Problem description The study of ionizing radiation effects on biological systems of different organization levels is of specifc attention. Changed environ- mental conditions of the radionuclide contaminated areas initiate the various radiological effects in natural non-human biota (Beresford et al., 2016; Br� echignac et al., 2016; Garnier-Laplace et al., 2013; Geras’kin et al., 2008, 2013; Grodzinsky et al., 1991; Gudkov et al., 2012a, 2012b; 2016a,b; Kuzmenko, 2018; Mothersill et al., 2017; Oudalova, 2011; Pozolotina et al., 2008). The consequences of wide-scale disasters at the nuclear fuel cycle facilities, such as Kyshtym disaster (USSR, 1957), Three-Mile Island accident (USA, 1979), Chernobyl disaster (USSR, 1986), Fukushima disaster (Japan, 2011), lead to revision of actual approaches of the radiological effects and risk assessment, as well as to development the grounded scientifc databases of the long-term low-dose ionizing radiation effects on non-human biota. Such databases were founded and developed within European Commission’s Framework Programmes for assessment and forecasting of probable effects at population and ecosystem levels (FREDERICA Database, 2000). 1.2. Vascular plants in radioecological studies Investigation of early ontogenesis’s disorders provide important in- formation about the vascular plant damages, capable of leading to probable population change by long-term and low-intensive ionizing radiation exposure. Thus, for example under birch pollen germination in 1987–88 from the Chernobyl Exclusion Zone (CEZ), a DNA repair ability decrease up to the complete lack, was found (Grodzinsky et al., 1991). Up to 80% of the morphological abnormalities in winter wheat seedlings of 1987 vegetation from the CEZ were found (Grodzinsky, 2008). Nur- gudin et al. (2009) found changes in the shape and color of seeds of the reed from the CEZ water-bodies and 72% infertility of its panicles. In 2009–12 it was mentioned a decrease in the reed seeds vitality in the * Corresponding author. E-mail addresses: a_yavnyuk@ukr.net (A.A. Iavniuk), shevtsovanl245@gmail.com (N.L. Shevtsova), digudkov@gmail.com (D.I. Gudkov). Contents lists available at ScienceDirect Journal of Environmental Radioactivity journal homepage: http://www.elsevier.com/locate/jenvrad https://doi.org/10.1016/j.jenvrad.2020.106256 Received 22 November 2017; Received in revised form 10 March 2020; Accepted 18 March 2020