The effect of cytokinins on shoot proliferation, biochemical changes and genetic stability of Rhododendron ‘Kazimierz Odnowiciel’ in the in vitro cultures

Abstract

Shoot proliferation is a very important micropropagation phase, decisive for economic efficiency of this method for a given taxon. To obtain a high multiplication ratio and a good quality of microshoots a detailed propagation protocol must be developed for particular species or even cultivars. Rhododendron ‘Kazimierz Odnowiciel’ is a relatively new cultivar distinguished by large, beautiful flowers and high frost resistance so there is a need to develop an efficient method of its propagation to satisfy a growing demand for this plant. The aim of the experiment was to evaluate effects of cytokinins: meta-Topolin (mT), zeatin (ZEA), 6-benzyladenine (BA), thidiazuron (TDZ), 2-isopentenyladenine (2iP), or the combination of 2iP+ZEA on proliferation of shoots in R. ‘Kazimierz Odnowiciel’ cultured on Anderson’s medium (AN). Biochemical changes in plant material affected by cytokinins during this phase of micropropagation were determined and occurrence of genetical changes was followed using ISSR markers. TDZ, ZEA or the combination of ZEA+2iP resulted in 100% explant regeneration. On the medium with TDZ or ZEA over two new shoots per explant were produced but the highest proliferation was attained on the medium containing ZEA+2iP – over three shoots per explant. Microshoots developed in this treatment had also the highest contents of chlorophyll, carotenoids and soluble sugars as well as the highest catalase activity. Microshoots formed on the medium with zeatin showed the lowest polymorphism (below 4%) relative to a stock plant.

IRAPs in Combination with Highly Informative ISSRs Confer Effective Potentials for Genetic Diversity and Fidelity Assessment in Rhododendron

“…Wei et al (2018) , for example, grew R. fortunei seedlings in vitro and developed the most appropriate conditions for micropropagation [7]. Nowakowska et al (2022) cultured Rhododendron 'Kazimierz Odnowiciel' in vitro and demonstrated the effect of cytokinins on shoot proliferation and genetic stability of plants [8]. However, the in vitro propagation of many endangered Rhododendron species, e.g.…”

“…The IRAP markers showed a high polymorphism in Rhododendron plants, as high as 96.7%, which are close to those of 94% of polymorphisms in Bletilla striata [25], and 98% of polymorphisms in Phyllostachys species [26] as calculated by IRAPs, respectively. Previously, ISSRs were demonstrated to be polymorphic for genetic variation detection [8], currently, IRAP marker was justified to be more effective in polymorphism assessment for rhododendrons. Likewise, EMR is the number of markers generated per primer assay [22], and the EMR value for IRAPs (14.55) was greater than that for ISSRs (12.21).…”

“…The use of ISSRs to detect genetic fidelity of somaclonal clones has been reported in Rhododendron [8]. In this study, IRAPs and ISSRs were employed to detect the somaclonal variation among the 15 individuals of R. bailiens callus which were subcultured for different cycles.…”

Pengaruh konsentrasi Benzylaminopurine terhadap pertumbuhan eksplan tunas aksilar rami klon lokal Wonosobo secara in vitro

“…Konsentrasi BAP yang terlalu tinggi menyebabkan ketidakseimbangan metabolisme dalam jaringan yang bisa jadi memperlambat proliferasi tunas. Nowakowska et al (2022), peningkatan sitokinin pada regenerasi tunas meningkatkan kandungan hidrogen peroksida yang menjadi berbahaya karena dapat merusak elemen sel struktural akibat oksidasi dan degradasi yang memicu kematian sel sehingga memperlambat regenerasi tunas.…”

Biotechnological interventions in banana: current knowledge and future prospects

“…Shoot multiplication is the most crucial step in the development of an efficient micropropagation protocol that directly affects the success of the given protocol ( Pati et al., 2006 ; Nowakowska et al., 2022 ) ( Figures 2 c, 2d). Various factors that greatly influence the shoot multiplication in bananas are highlighted in this section.…”