Logotipo del repositorio

Artículos Científicos

URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/14754

Examinar

Examinando Artículos Científicos por browse.metadata.rights "Atribución 4.0 Internacional"

Seleccione resultados tecleando las primeras letras
Mostrando 1 - 2 de 2
  • Miniatura
    Ítem
    Influence of Physico-Chemical Factors on the Efficiency and Metabolite Profile of Adult Pinus radiata D. Don Bud Organogenesis
    (Universidad Nacional, Costa Rica, 2022-09-10) Rojas Vargas, Alejandra; Castander-Olarieta , Ander; Montalbán, Itziar Aurora; Moncalean, Paloma
    Genetic improvement programs for conifer forest species face the challenge of propagating elite individuals with superior characteristics in the present landscape of climate change; the problem is focused on the fact that when these individuals have shown the desirable traits, they have changed phase and therefore have lost the ability to be propagated by traditional methods. Based on our previous works on Pinus spp. regeneration of adult trees through organogenesis and trying to improve the protocol in Pinus radiata, our objective was to analyze the influence of collection dates and different 6-benzyladenine (BA) concentrations in the first phase of shoot induction, as well as the effect of different light types on the success of root induction. Moreover, we were interested in studying the effect of the abovementioned physico-chemical factors on the amino acid and carbohydrate content in the shoots developed in vitro. Reinvigorated shoots were obtained in both BA concentrations (22 or 44 M), although the highest BA concentration showed the best results in terms of shoot induction (explants forming shoots (46%) and number of shoots per explant (1.95 0.52)) when using initial explants collected in the first week of February. The percentage of explants forming shoots (EFS) was genotype-dependent. Explants from genotype A induced with the highest BA concentration showed the highest EFS (91%). With respect to the light treatment applied, significant differences in root induction (20%) and in the number of roots per explant (4.62 0.65) were observed in shoots cultured under white FL. Finally, significant differences in different phases of the rooting process were detected in the amounts of fructose, glucose and sucrose and in the content of threonine and tyrosine.
  • Miniatura
    Ítem
    Testing Explant Sources, Culture Media, and Light Conditions for the Improvement of Organogenesis in Pinus ponderosa (P. Lawson and C. Lawson)
    (Universidad Nacional, Costa Rica, 2023-02-14) Rojas Vargas, Alejandra; Castander-Olarieta , Ander; Velez, Maria Laura; do Nascimento, Antonia Maiara Marques; Pereira, Cátia; Martins, João; Zuzarte, Monica; Canhoto, Jorge; Montalbán, Itziar Aurora; Moncaleán, Paloma
    Pinus. ponderosa (P. Lawson and C. Lawson) is a commercial tree and one of the most important forest species in North America. Ponderosa pine suffers hardship when going through vegetative propagation and, in some cases, 15–30 years are needed to achieve full reproductive capacity. Based on previous works on P. ponderosa regeneration through in vitro organogenesis and trying to improve the published protocols, our objective was to analyze the influence of different types of explants, basal culture media, cytokinins, auxins, and light treatments on the success of shoot multiplication and rooting phases. Whole zygotic embryos and 44 M 6-benzyladenine showed the best results in terms of explants survival. For shoot organogenesis, whole zygotic embryos and half LP (LP medium, Quoirin and Lepoivre, 1977, modified by Aitken-Christie et al., 1988) macronutrients were selected. A significant positive interaction between whole zygotic embryos and half LP macronutrients was found for the percentage of explants forming shoots. Regarding the light treatments applied, a significantly higher percentage of shoots elongated enough to be rooted was detected in shoots growing under blue LED at a light intensity of 61.09 mol m2 s1. However, the acclimatization percentage was higher in shoots previously cultivated under fluorescent light at a light intensity of 61.71 mol m2 s1. Anatomical studies using light microscopy and scanning electron microscopy showed the light treatments promoted differences in anatomical aspects in in vitro shoots; needles of plantlets exposed to red and blue LEDs revealed less stomata compared with needles from plantlets exposed to fluorescent light.