On the genetic control of the regeneration response in the dioecious Melandrium album

Abstract

Summary.Melandrium album (2n = 24), a dioecious species with heteromorphic sex chromosomes (XY, male; XX, female), has a strong genetic commitment for sex determination. So far the in vitro regeneration response in this species has appeared to be restricted to female plants. We report here a procedure for achieving active regeneration from explants and mesophyll protoplasts of selected female plants. Shoots were frequently induced in hormone-free media and in the presence of cytokinins or low concentrations (<0.5 nag/l) of auxins. The in vitro conditions employed did not affect the sex expression of the regenerated plants. Crosses between selected female plants with high regeneration capacity and nonregenerating males indicated that the regeneration response is genetically controlled and can be transmitted sexually into male and female progenies.

In Vitro Propagation of Paronychia chartacea

“…In vitro techniques also have been used for the propagation of several Caryophyllaceae genera. Successful establishment of Dianthus caryophyllus L. (Frey and Janick, 1991;Kim and Kang, 1986), Gypsophila paniculata L. (Han et al, 1991;Kusey et al, 1980), and Melandrium album L. (Ye et al, 1992) have been reported; however, the wild P. chartacea population is steadily declining because of reduced seed production and viability primarily due to encroaching commercial development and agricultural land use (Christman and Judd, 1990). Therefore, our objective was to develop a micropropagation protocol to produce adequate plant material for eventual reintroduction studies in landscape preservation areas.…”