Use of biodegradable polyester-based microvessels for micropropagation of mature Eucalyptus microcorys

Abstract

Background: Micropropagation, an in vitro vegetative propagation technique using small propagules is one of the main applications of plant tissue culture. It can be used to clone specific plants with desired traits and reduce the cost of plant propagation. In this study, we developed a protocol for micropropagation of Eucalyptus microcorys F.Muell using a selected mature tree, in which we tested various combinations of different culture media and evaluated the use of biodegradable polyester-based microvessels during the adventitious rooting and acclimatisation phases. Methods: Epicormic shoots were used as an explant source. After the in vitro explant establishment and multiplication, we tested 8 combinations of BAP, NAA and IBA in the elongation phase. Three types of microvessels were tested in the adventitious rooting phase and acclimatisation of the microcuttings. Results: Epicormic shoots had an establishment percentage of 40.6% and a total of 820 explants were generated by the 11th subculture, with an average of 12 buds per explant. Best shoot elongation results were achieved with BAP (0.05 mg L-1) + NAA (1 mg L-1) and BAP (0.05 mg L-1) + NAA (1 mg L-1) + IBA (1 mg L-1) combinations, whereas microvessel types M2 and M3 provided higher rooting and acclimatisation. According to the results of ISSR markers, at the end of 535 days of in vitro cultivation, cloning was successful between acclimatised micro-plantlets and the parent plant. Conclusions: The micropropagation protocol using microvessels was efficient in producing E. microcorys clonal micro-plantlets and is recommended for further studies with this species, and for testing in the micropropagation of other species.

Spectral quality influence on in vitro morphophysiological responses of Eucalyptus dunnii Maiden and Eucalyptus grandis W.Hill ex Maiden × E. urophylla S.T.Blake

“…In contrast, the use of white spectral quality resulted in greater oxidation in explants of Corymbia torelliana × C. citriodora (Souza et al 2018). Tissue oxidation is a problem with the micropropagation of woody species, as reported in other studies (Oliveira et al 2016;Souza et al 2019;Souza et al 2020b;Faria et al 2021;Faria et al 2022;Souza et al 2022). These results may be linked to internal environmental factors that affect the vigor of explants, where smaller flasks tend to have reduced carbon dioxide concentrations and high ethylene concentrations, and may also be affected by light irradiation, air temperature, and relative humidity (Tisarum et al 2018;Chen et al 2019;Souza et al 2021).…”

“…In Brazil, eucalypts forests are mainly made up of clonal varieties bred from superior genotypes that are better adapted since it enables the mass multiplication of vegetative propagules in a short time and in a small area (Molinari et al 2021;Silveira et al 2020;Ashrafzadeh & Leung 2021). Nevertheless, in vitro growth and development of different species in micropropagation stages are influenced by several factors (Batista et al 2018;Miranda et al 2020;Faria et al 2021;Faria et al 2022).…”

Evaluation of total protein, peroxidase, and nutrients measured by pXRF for the determination of tissue rejuvenation/reinvigoration of Eucalyptus microcorys

“…It is noteworthy that, even with statistical differences in peroxidase activity, all propagation techniques carried out in this study resulted in a degree of tissue rejuvenation and/ or reinvigoration. Micropropagation has several advantages for the propagation of tree species, especially for ones that are difficult to root, whereas other techniques rarely succeed (Atala et al 2022;Faria et al 2022). Several studies recommend this propagation technique using epicormic shoots, mainly for species with high ontogenetic ages, for instance, for Eucalyptus benthamii Maiden & Cambage 13-years-old (Baccarin (Oliveira et al 2015).…”