Survival strategies of Silene tatarica (Caryophyllaceae) in riparian and ruderal habitats

Abstract

Certain morphological and anatomical structures of riparian plants might be important for their survival during the season when they are exposed to severe stress caused by flooding, burial, fluctuating temperatures, and drought. These rare characteristics were studied as related to their ecological consequences in a threatened plant, Silene tatarica (L.) Pers., in riparian and ruderal habitats. The main differences between the habitats were morphological and closely related to the habitat properties, whereas the basic anatomy of structures was similar. After sand burial, most riparian plants formed vertical rhizomes and new meristems by bud ramification in the stem base near the ground surface. Special anatomical structures of fleshy underground stems and roots seem to allow plants to be resilient. Moreover, some primitive structures, such as vascular elements with helical and scalariform thickenings, collenchyma, and abundant xylem parenchyma, may increase the resilience of organs. High amounts of saccharose in fleshy rhizomes and roots can increase the cold resistance of plants. The flat shape and structures of tiny seeds may enhance the long-distance dispersal by water. We suggest that the synergism of these structures enables the survival of S. tatarica in highly disturbed habitats with fluctuating water levels.Key words: bud clusters, burial, flooding, growth habit, tensile strength, vertical rhizome.