Browsing by Author "Carlos Oropeza"
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Item Exogenous sucrose can decrease in vitro photosynthesis but, improve field survival and growth of coconut (Cocos nucifera L.) in vitro plantlets(2005) Gabriela Fuentes; Carlos Talavera; Carlos Oropeza; Yves Desjardins; Jorge M. SantamariaItem In situ PCR detection of phytoplasma DNA in embryos from coconut palms with lethal yellowing disease(2003) Ivan Cordova; Phil Jones; Nigel A. Harrison; Carlos OropezaItem In situ PCR detection of phytoplasma DNA in embryos from coconut palms with lethal yellowing disease(2003) Ivan Cordova; Phil Jones; Nigel A. Harrison; Carlos OropezaDNA of the lethal yellowing (LY) phytoplasma was detected in 13 of 72 embryos from fruits of four diseased Atlantic tall coconut palms by polymerase chain reaction (PCR) assays employing phytoplasma universal rRNA primer pair P1/P7, nested LY group-specific rRNA primer pair 503f/LY16Sr or LY phytoplasma-specific nonribosomal primer pair LYF1/R1. Phytoplasma distribution in sectioned tissues from six PCR positive embryos was determined by in situ PCR and digoxigenin-11-deoxy-UTP (Dig) labelling of amplification products. Dig-labeled DNA products detected by colourimetric assay were clearly evident on sections from the same three embryos investigated in detail by in situ PCRs employing primer pairs P1/P7 or LYF1/R1. Deposition of blue-green stain on sections as a result of each assay was restricted to areas of the embryos corresponding to the plumule and cells ensheathing it. By comparison, similarly treated embryo sections derived from fruits of a symptomless Atlantic tall coconut palm were consistently devoid of any stain. Presence of phytoplasma DNA in embryo tissues suggests the possible potential for seed transmission which remains to be demonstrated.Item Influence of form of activated charcoal on embryogenic callus formation in coconut (Cocos nucifera)(2010) Luis Saenz; Gaston Herrera-Herrera; Frank Uicab-Ballote; Jose Luis Chan; Carlos OropezaDevelopment of micropropagation protocols for Cocos nucifera has progressed slowly. Activated charcoal is included in the culture medium of each protocol, mainly to prevent tissue browning. Charcoal production procedures can affect the properties of different brands. In this study, eight types of activated charcoal were evaluated for their effects on free 2,4-dichlorophenoxyacetic acid level, pH, conductivity, and osmolarity of the culture medium and on the frequency of embryogenic callus induction. Moreover, the effect of particle size of the optimum charcoal type on embryogenic callus development was also studied. Charcoal type had a significant effect on (Y3) culture medium properties. Free 2,4-D was highest in Reactivos y Productos Quı´micos Finos-containing medium and pH was lowest in MERCK-containing medium. Charcoal type also influenced embryogenic callus induction, with acid washed for plant cell and tissue culture-, DARCO- and United States Pharmacopeia- containing media promoting*60% embryogenic callus, but with different optimal 2,4-D concentrations. Particle size profiles varied among all charcoal types, although small particle fraction (\\38 lm) was abundant in all. Use of small particle fractions produced higher frequencies of embryogenic callus (70%) than either large particle or whole charcoal fractions.Item Leaf proteins as markers useful in the genetic improvement of coconut palms(1998) Rolando Cardena; Carlos Oropeza; Daniel ZizumboThere is a need to identify genetic markers that can assist coconut (Cocos nucifera L.) breeding programs.With that objective, electrophoretic patterns of leaf peroxidases, endopeptidases and coomassie blue stained proteins were analysed in four cultivars (‘West African Tall’, ‘Rennell Tall’, ‘Malayan Yellow Dwarf’, ‘Cameroon Red Dwarf’), and in the hybrids PB121 (‘Malayan Yellow Dwarf’ ‘West African Tall’) and PB111 (‘Cameroon Red Dwarf’ ‘West African Tall’). The polymorphisms detected fit the expression of two alleles of a dimeric peroxidase, two alleles of a monomeric endopeptidase, and a pair of active and null alleles of a coomassie blue stained protein. Four distinctive genotypes were identified. One for each of the tall cultivars, another for both of the dwarf cultivars, and the last for both of the hybrids. Applications of the markers in breeding programs, and in research concerning reproductive biology and phylogeny, are discussed.Item A peak in global DNA methylation is a key step to initiate the somatic embryogenesis of coconut palm (Cocos nucifera L)(2020) Pedro Osorio‑Montalvo; Clelia De‑la‑Peña; Carlos OropezaItem A peak in global DNA methylation is a key step to initiate the somatic embryogenesis of coconut palm (Cocos nucifera L)(2020) Pedro Osorio‑Montalvo; Clelia De‑la‑Peña; Carlos Oropeza; Geovanny Nic‑CanItem Progress on coconut micropropagation in Mexico(2018-02) Carlos Oropeza; Luis Saenz; Jose Luis Chan; Maria Narvaez; Guillermo Rodriguez; Carlos Borroto; Gabriela Sandoval; Teresa Perez-NunezItem Protein Phosphorylation during Coconut Zygotic Embryo Development(1998) Ignacio Islas-Flores; Carlos Oropeza; Teresa Hernandez-Sotomayor, S.M.