Induction of budding on chloronemata and caulonemata of the moss, Physcomitrella patens, using isopentenyladenine.

The bud-inducing effect of the cytokinin N(6)-(Δ(2)-isopentenyl)-adenine (i(6)-Ade) was examined in the moss Physcomitrella patens growing in liquid culture. Under these conditions, buds could be induced on chloronemata as well as on caulonemata. By application of i(6)-Ade, bud-formation was accelerated in both types of tissue. The number of buds, their size and their site of development were dependent on the concentration of the cytokinin in the range of 10(-7) M to 10(-5) M. Moreover, the percentage of caulonema cells increased with a cytokinin concentration of 10(-5) M. These results indicate that chloronema cells may also function as target cells for exogenous cytokinins. The composition of proteins from caulonemata and chloronemata of two different species (P. patens and Funaria hygrometrica), grown on solid medium were compared. No differences could be detected between the protein patterns of caulonemata and chloronemata of the same species while between the two species the differences were obvious.