Inhibitory Effect of Jasmonic Acid on Gametophytic Growth, Initiation and Development of Sporophytic Shoots in Equisetum arvense

Summary An in vitro culture system of Equisetum arvense L. was used to analyze the effects of jasmonic acid (JA) on gametophytic growth and initiation and development of sporophytic shoots. The growth of gametophytic and sporophytic tissues was inhibited by JA if the culture medium contained permanently this growth regulator; preincubation of these tissues with JA and subsequent cultivation on a JA-free medium were nearly inefficient. JA inhibited effectively the initiation of sporophytic shoots, if applied simultaneously with cytokinin (benzyl adenine), which is absolutely required for this initiation process. The interaction between JA and cytokinin in sporophytic shoot initiation in E. arvense may be an important control for the regulation of this physiological process.