Comprehensive characteristics and genetic diversity of the endemic Australian Viola banksii (section Erpetion, Violaceae)
Monika Kwiatkowska A , Justyna Żabicka A , Grzegorz Migdałek B , Piotr Żabicki A , Marlena Cubała A , Jerzy Bohdanowicz C , Aneta Słomka A H , Monika Jędrzejczyk-Korycińska D , Elwira Sliwinska E , Klaudia Sychta A , Thomas Marcussen F , Kevin Thiele G and Elżbieta Kuta AA Department of Plant Cytology and Embryology, Institute of Botany, Jagiellonian University, 9 Gronostajowa str., 30-387 Cracow, Poland.
B Institute of Biology, Pedagogical University of Cracow, 2 Podchorążych str., 30-084 Cracow, Poland.
C Department of Plant Cytology and Embryology, Faculty of Biology, University of Gdańsk, 59 Wita Stwosza str., 80-308 Gdańsk, Poland.
D Department of Botany and Plant Protection, University of Silesia, 28 Jagiellońska str., 40-032 Katowice, Poland.
E Laboratory of Molecular Biology and Cytometry, UTP University of Science and Technology, Prof. S. Kaliskiego Ave 7, 85-789 Bydgoszcz, Poland.
F CEES, Department of Biosciences, University of Oslo, PO Box 1066 Blindern, NO-0316, Norway.
G School of Biological Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
H Corresponding author. Email: aneta.slomka@uj.edu.pl
Australian Journal of Botany 67(2) 81-98 https://doi.org/10.1071/BT18233
Submitted: 5 December 2018 Accepted: 19 February 2019 Published: 26 April 2019
Abstract
Viola banksii, the type species of section Erpetion, is endemic in eastern mainland Australia. In this paper we characterise morphological and anatomical features and assess genome size and genetic diversity in combination with the breeding system. V. banksii develops exclusively chasmogamous flowers. Ovules are anatropous, crassinucellate and bitegmic, the female gametophyte is of the Polygonum type, and the embryo is of Asterad type surrounded by nuclear endosperm. Pollen is non-heteromorphic, 3-aperturate, and highly viable. V. banksii grows in shade on moist, well drained, often sandy soils, and this is reflected in the anatomy of its organs, which includes a lack of subepidermal collenchyma in aerial parts, large leaf epidermal cells with thin cell walls, a narrow cuticle layer, and vascular bundles with xylem that are not rich in vessels. V. banksii is tolerant to zinc and lead based on phytotoxicity test. The high chromosome number (2n = 10x = 50) does not correspond to a small genome size (2C DNA = 1.27 pg). Low mean intra-populational gene diversity (HS = 0.077) detected by ISSR markers confirms the strong influence of selfing and clonal propagation by pseudostolons. Unique morphological traits of V. banksii include nyctinastic petal movement, the lack of a floral spur, the presence of gland-like protuberances on two stamens, and the presence of pseudostolons, which could be a synapomorphy for the whole section.
Additional keywords: anatomy, flower, genetic diversity, ISSR markers, morphology, tolerance to heavy metals, vegetative organs, Viola banksii.
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