REGENERATIVE POTENTIAL AND ITS VARIABILITY IN DIFFERENT TOPOPHYSICAL ZONES OF Kalanchoe daigremontiana LEAVES IN in vitro CULTURE CONDITIONS.

Plants of the genus Kalanchoe are the most frequently purchased potted plants because of their decorative qualities and easy cultivation. Modern commercial plants have unique shapes that are usually not genetically determined; hence, in vitro cultures are used to propagate such specimens. The efficiency of regeneration is significantly affected by the type of explant used when that explant was previously located on one of several parts of a complex plant organ. The study aimed to investigate the influence of the topophysical location of collected explants on the regeneration efficiency of adventitious shoots. Various regeneration pathways were observed in the in vitro micropropagation of Kalanchoe daigremontiana leaf fragments, i.e., direct and indirect organogenesis from the callus stage. The results show a dependent relationship between the location of the collected explant and its regenerative potential. The most remarkable regenerative capacity of K. daigremontiana was found in leaf blade fragments taken from the middle and proximal zones. In addition, the explants collected from the marginal zone of the leaf blade were notably more valuable than those from the part located near the midrib. The research results indicate that the growth and development of new seedlings propagated vegetatively with the in vitro method depends on their location on the mother plant. [ABSTRACT FROM AUTHOR]