In vitro establishment of Bambusa oldhamii Munro from field-grown matrices and molecular identification of endophytic bactéria

Abstract

In plant micropropagation, the establishment stage is difficult, due to the presence of microorganisms in tissues from field-grown matrices, especially for bamboo. This study aimed to establish an efficient asepsis protocol for Bambusa oldhamii explants from field plants, as well as to carry out the molecular identification of a possible endophytic bacterial isolate. The explants were exposed to 70 % alcohol, 1 % sodium hypochlorite (NaOCl), 0.1 % mercuric chloride (HgCl2), thiophanate-methyl (Cercobin®) and chlorhexidine digluconate (2 % Riohex®) in different combinations, and introduced into Murashige and Skoog culture medium (solid or liquid), supplemented or not with 4 mL L-1 of Plant Preservative Mixture (PPMTM), totaling seven treatments. The asepsis and immersion of the explants in the liquid culture medium containing 4 mL L-1 of PPMTM visually inhibited the bacterial and fungal growth, allowed the development of shoots with a mean length of 2.2 cm and posterior subcultures, being the best treatment used for the in vitro establishment of B. oldhamii. The molecular identification of an endophytic bacterium performed by 16S rDNA sequencing allowed to identify the bacterial isolate as Ralstonia sp., with 100 % of similarity, and the phylogenetic analysis grouped it with Ralstonia pickettii. In addition, the bacterial isolate showed to be sensitive to 4 mL L-1 of PPMTM by the minimum inhibitory concentration test.

A Concise Review of Dendrocalamus asper and Related Bamboos: Germplasm Conservation, Propagation and Molecular Biology

“…As a consequence, vegetative propagation from layering, off-set and rhizome planting, marcotting and branch and culm cuttings are used for propagating the bamboos [17,65,66]. The traditional bamboo propagation methods, on the other hand, are detrimental to mother plants during collection, involving high labor costs, transportation difficulties, bulky materials and seasonal dependence, which is typically limited to a short period of time, and these techniques are only effective for small-scale production [67,68]. The first report on a successful tissue culture of bamboo was done by reference [69], who described the embryo culture of D. strictus on a sucrose-enriched medium.…”