Shoot formation from leaf explants and apical meristems of Peperomia obtusifolia A. Dietr.: stability of ploidy level in their subcultures

摘要

Leaf explants of P. obtusifolia were cultured on Murashige and Skoog basal medium (MS) with various growth regulators in order to regenerate shoots. On MS basal medium with auxins (IAA or NAA) and kinetin, the explants produced green callus and manyroots but few shoots. On MS supplemented with auxins and benzyladenine, 30-40% of the explants produced green callus and numerous shoots, but no roots. The shoots, after 4-5 months, were removed from initial explants and transferred separately onto MS basal medium or MS supplemented with IBA for elongation and rooting. Histological studies showed that the callus was associated with spongy parenchyma cells near the vascular tissue from which shoots regenerated. Subcultured material was more productive in a shorter time than the initial cultures. Chromosome numbers in root tip cells of the mother plant and of all in vitro plant generations remained constant (2n = 22).