Title : In vitro rooting of micropropagated shoots from the clonal rootstock of cherry, Colt
Abstract:
One of the decisions in planning a fruit plantation is the selection of the rootstock, since these make up the root system of fruit trees and provide vital elements such as anchoring, absorption of water, nutrients, and protection against pathogens. There are difficulties associated with the propagation of this culture, with the in vitro culture technique being an excellent opportunity that will allow its massive propagation in a short term. In this research, an efficient in vitro rooting protocol for the clonal cherry rootstock, Colt, has been developed for the first time. The experiment was carried out in the Plant Biotechnology - Biotec laboratory of the company Camposol S.A. In this study, the effect of different types of basal culture medium, source of iron, amino acids and growth regulators for in vitro rooting was analyzed. In vitro shoots or microshoots of 3 to 5 cm in length were grown in basal culture medium MS (Murashige & Skoog), N & N (Nitsch & Nitsch) and Q & L (Quorin & Lepoivre) in the following concentrations of macrosalts: 25%, 50%, 75% and 100%, in combination with different concentrations of 3-indole butyric acid (IBA): 0, 1.0, 2.0 and 3.0 mg/L, adding as an extra source of iron: 50 mg/L FeNa-EDDHA and enriched with amino acid: 1.0 mg/L proline; in addition, 20 gr/L of sucrose and 7.0 gr/L of phytagel. The plants were maintained in the planting room with a temperature of 25 ± 2 °C. After four weeks of culture, the elongated shoots were isolated and the response to rooting in vitro was evaluated. The addition of auxin indole-3-butyric acid (IBA) 1.0 mg/L in the MS culture medium with 50% concentration of macrosalts, enriched with 50 mg/L of FeNa-EDDHA and 1.0 mg/L of proline, was highly efficient for in vitro rooting and a significant improvement in plant quality. The results showed that the best rooting percentage obtained was 85% after two weeks of cultivation. Finally, the rooted in vitro plants were removed from the culture medium and transferred to a substrate composed of peat and perlite (2:1 v/v). After 60 days, 90 to 100% of plants successfully rooted and reactivated their growth after the greenhouse acclimatization process. This technique is effective in guaranteeing a high ex vitro survival rate of the clonal rootstock (Colt), opening opportunities for scaling the production of rootstock plants in the laboratory and improving the quality of post-transplant plants.
Audience Take Away Notes:
- The in vitro cultivation of fruit species is presented as an advantage for the in vitro clonal propagation of cherry clonal rootstocks, being a tool for efficient propagation of plants of excellent genetic and phytosanitary quality
- Know and motivate the development and development of in vitro cultivation techniques for fruit species that are difficult to propagate, such as cherry rootstock trees
- New experiences and research in the development of in vitro culture protocols for the development of new cherry clonal rootstocks for new areas where this crop expands, as well as for replanting in existing areas. In addition to contributing to genetic improvement programs, since the production of orchards established with new rootstocks will continue to be evaluated in various environments, in addition to promoting other lines of research such as genomics, stress physiology, agronomy and phytosanitary
- One of the most critical stages in in vitro clonal propagation is the acclimatization of plants in ex vitro conditions. For this, it is essential to achieve plants with good foliar and root development for the post- transplant stage and the vigorous growth of the tree. It is essential to have a good root system early with the formation of root structures that guarantee the anchoring of the plants to the substrate, which is why the in vitro rooting stage is important
- This study will be a valuable collaboration for the development of protocols for new clonal cherry rootstocks, as well as facilitating knowledge of the in vitro rooting and ex vitro acclimatization processes to guarantee a good survival rate in the critical stages of the cultivation technique. in vitro, where high mortality generally occurs if critical conditions are not controlled.
- Entering species as challenging as fruit crops of cherry rootstock trees, starting with plants of excellent genetic and phytosanitary quality, would be a first criterion in selecting the vigor observed in the new genotypes that are tested. Having experience and knowledge in the introduction to in vitro culture to evaluate in advance the stages of establishment, multiplication and then the ease of rooting in vitro, will guarantee the use of the technique of this species in the different rootstocks that are chosen, thereby Material will be available to carry out the various evaluations and obtain information for different agronomic and fruit quality characteristics in this crop
