Original paper
Cytokinin is an effective stimulator for turion sprouting of Potamogeton crispus
Zhu, Congming; Li, Kai; Yang, Tewu; Nie, Zhongnan; Li, Xinghua; Zhu, Duanwei; Hu, Xuebo; Zhou, Hanwen
Fundamental and Applied Limnology Volume 186 Nr. 3 (2015), p. 271 - 278
published: May 1, 2015
ArtNo. ESP141018603007, Price: 29.00 €
Abstract
Turions are the main propagules of Potamogeton crispus, a submersed aquatic macrophyte that is distributed widely in temperate and subtropical waters. Turion sprouting is a critical step in the life cycle of the plant and relates closely to the population dynamics of the species. The clarification of the physiological mechanisms specific to plant hormone regulation on turion sprouting is instrumental in understanding the population decline and developing strategies to revitalize the species in eutrophic waters. In this study, dormant turions were exposed for a short period (4 h) to different concentrations (0, 0.15, 0.30, 0.45, 0.60, 0.75 mM) of gibberellic acid (GA3), 6-benzyladenine (6-BA) and naphthylacetic acid (NAA), to investigate their effects on turion sprouting of P. crispus in the laboratory. Moreover, 20 mM metyrapone, an inhibitor of zeatin-type cytokinin biosynthesis, was also applied either alone or in combination with 0.30 mM 6-BA to explore the possible function of endogenous zeatin-type cytokinins in regulating turion sprouting. The contents of starch and soluble sugars were measured during the turion sprouting. Applications of 6-BA, GA3 and NAA could break turion dormancy rapidly and promoted starch degradation. Among these substances, 6-BA showed the strongest effect to stimulate axillary bud sprouting in turions. Metyrapone significantly inhibited turion sprouting. These suggest that zeatin-type cytokinins may play an important role in regulating turion sprouting, and cytokinins could be used to increase sprouting of turions in P. crispus.
Keywords
dormancy • plant growth substances • turion • starch reserves • potamogeton crispus