Vegetative propagation of Chara rudis (Characeae, Chlorophyta)

Abstract

Skurzyński P. and Bociąg K. 2011. Vegetative propagation of Chara rudis (Characeae, Chlorophyta). Phycologia 50: 194–201. DOI: 10.2216/09-64.1

Studies on the germination of charophyte oospores in lake populations have revealed that oospores germinate rarely and in small numbers. Despite this, perennial populations of charophytes continue to exist in deep lakes in Poland. We examined the reproductive potential of vegetative parts of charophyte thallus to determine how these might contribute to charophyte persistence. Thallus fragments of Chara rudis can form a propagule bank and function as vegetative propagules that give rise to new thalli (ramets) in Polish lakes. Experimental results show that naturally produced thallus fragments are present on the benthic sediment surface and can initiate new growth, resulting in new plants. Multinode fragments and apical fragments produce the largest number of ramets. Thallus fragments from the deep zones (> 5 m) produce the more ramets than those from shallower areas. Thus, thallus fragments play a significant role in population persistence in the deep areas of the lake. Given the reported low germination rates of oospores from perennial populations, it is likely that vegetative reproduction, via thallus fragments, has an important role in population maintenance.

ACKNOWLEDGEMENTS

We wish to express our appreciation to Prof. Józef Szmeja for his comments and observations on the text. We are grateful to anonymous referees for their helpful comments on the manuscript, to Michelle T. Casanova for collecting the necessary literature on the subject, to Marek Merdalski for his assistance in the field works and to Emilia Pokojska and Magdalena Dołomisiewicz for translating this text into English. This work was financed by education funds for 2007–2010 as a research project (project no. N N304 4113 33 of the Ministry of Science and Higher Education).