Propagación in vitro de Heliconia standley Macbride

The propagation of Heliconia sp. in Cuba is conceived by applying traditional methods, which are mainly based on sowing or planting rhizomes. Having a protocol for the in vitro culture would increase the yield and quality of the plants obtained. The aim of this study was to establish a protocol for in vitro propagation of H. standleyi. Experiments were conducted in each of the stages from establishment to acclimatization. The in vitro propagation of H. standleyi was achieved. For in vitro establishment, 2% of sodium hypochlorite, 20 min of disinfection and liquid culture medium were used. When using 2.0 mg.l-1 6-BAP and 0.65 mg.l-1 IAA, in the multiplication stage in semisolid culture medium, a 4.6 multiplication coefficient was obtained. It was demonstrated that explants should be higher than 3.0 cm to be transferred to rooting stage. A determining factor in the acclimatization stage to achieve a greater plant survival was the initial height of the explants (higher than 5.0 cm) to be sent to field after 45 days of culture.Key words: acclimatization, micropropagationLa propagación de Heliconia sp. en Cuba está concebida mediante la aplicación de los métodos tradicionales, los cuales se basan fundamentalmente en la siembra o plantación de rizomas. Contar con un protocolo para su cultivo in vitro permitiría incrementar la producción y la calidad de las plantas obtenidas. El objetivo de este trabajo fue establecer un protocolo para la propagación in vitro de H. standleyi. Se realizaron experimentos en cada una de las fases desde el establecimiento hasta la aclimatización. Se logró la propagación in vitro de H. standleyi. Para el establecimiento in vitro se empleó NaOCl al 2% y el tiempo de desinfección (20 min), así como el estado líquido del medio de cultivo para la fase de establecimiento. Al emplear 2.0 mg.l-1 6-BAP y 0.65 mg.l-1 AIA, en la fase de multiplicación con medio de cultivo semisólido, se logró obtener un coeficiente de multiplicación de 4.6. Se demostró que los explantes deben ser mayores de 3.0 cm para pasar a la fase de enraizamiento. Uno de los factores determinantes en la fase de aclimatización para lograr plantas con mayor supervivencia fue la altura inicial de los explantes (mayores de 5.0 cm) para poder enviarse al campo posterior a los 45 días de cultivo.Palabras clave: aclimatización, micropropagació

Establecimiento de un banco de plantas madre de caña de azúcar en condiciones semicontroladas para la propagación in vitro

The propagation of sugarcane (Saccharum spp.) Requires seed with physiological and phytosanitary quality. The work was carried out with the objective of establishing a bank of sugarcane mother plants under semi-controlled conditions to guarantee the efficiency of in vitro propagation with plants free of Xanthomonas albilineans. A greenhouse was modified and the structure was remodeled, a Sarán shade mesh (50%) and a sprinkler irrigation system were placed. The plants were grown in plastic containers (20 m3 volume) with a mixture of cachaça compost and zeolite 3:1. Stems of cultivars C98-357, C97-445 and C86-156, without symptoms of leaf scald and with six months of culture, were cut into segments with a bud. Hydrothermal treatment was applied and subsequently the biostimulant VIUSID Agro® (0.8 ml l-1) before the buds planting. At three months of culture, a serological diagnosis was made to detect the presence of X. albilineans. The negative plants were treated with biostimulants and the response of the in vitro establishment was evaluated. Adequate plant growth was achieved under the conditions described. The establishment of a bank of sugarcane mother plants under semi-controlled conditions and its management guaranteed that microbial contamination and phenolic oxidation decreased in the in vitro establishment phase. The effectiveness of the hydrothermal treatment combined with the semi-controlled conditions and the management of the plants make it possible to reduce the incidence of X. albilineans.La propagación de caña de caña de azúcar (Saccharum spp.) requiere de semilla con calidad fisiológica y fitosanitaria. El trabajo se realizó con el objetivo de establecer un banco de plantas madre de caña de azúcar en condiciones semicontroladas para garantizar la eficacia de la propagación in vitro con plantas libres de Xanthomonas albilineans. Se modificó una casa de cultivo y se remodeló la instalación, se colocó malla de sombra Sarán (50%) y un sistema de riego por aspersores. El cultivo de las plantas se realizó en recipientes de plástico (volumen de 20 m3)con una mezcla de compost de cachaza y zeolita 3:1. Tallos sin síntomas de escaldadura foliar y con seis meses de cultivo de los cultivares C98-357, C97-445, y C86-156 se cortaron en segmentos con una yema. Se aplicó tratamiento hidrotérmico y posteriormente el bioestimulante VIUSID Agro® (0.8 ml l-1) antes de la plantación de las yemas. A los tres meses de cultivo se realizó un diagnóstico serológico para detectar la presencia de X. albilineans.  Las plantas negativas se trataron con productos bioestimulantes y se evaluó la respuesta del establecimiento in vitro. En las condiciones descritas se logró el crecimiento adecuado de las plantas. El establecimiento de un banco de plantas madre de caña de azúcar en condiciones semicontroladas y su manejo garantizaron que disminuyera la contaminación microbiana y la oxidación fenólica en la fase de establecimiento in vitro. La efectividad del tratamiento hidrotérmico combinado con las condiciones semicontroladas y el manejo de las plantas permiten disminuir la incidencia de X. albilineans

In propagation Gerbera jamessonii H. Bolus

Gerbera is one of the horticultural crops of great demand on the Cuban local market, but its exploitation is limited because with the traditional multiplication methods established, it is not possible to comply with the demands of the “seeds”. This work was carried out at the biofactory of Las Flores de Servicios Comunales”, with the objective of establishing a methodology for the in vitro commercial propagation of Gerbera. Culture media and explant management in the different micropropagation phases were studied. The results obtained showed that with sodium hypochlorite at 0.5% during 10 minutes, a high disinfection of the shoot tips was achieved. With the combination of 6-bencilaminepurine (1.0 mg-l-1) and giberrelic acid (0.1 mg.l-1) in the culture medium, it was possible to increase the number of shoots per explant during establishment. In the multiplication phase, the best results were obtained with a combination of 6-BAP (2.0 mg.l-1) with AIA (0.65 and 1.3 mg.l-1) subculturing the explants greater than 1.0 cm individually in semisolid culture medium. A significant influence on the number of roots and growth of the explants was achieved adding indolacetic acid to the rooting medium and using for the subculture, explants greater than 3.0 cm. The quality of the explants influenced significantly in the acclimatization phase, demonstrating that the plants rooted in vitro should be 3.0 cm in height. Key words: explants, disinfection, shoot tip, culture mediu

Contemporary use of cefazolin for MSSA infective endocarditis: analysis of a national prospective cohort

Objectives: This study aimed to assess the real use of cefazolin for methicillin-susceptible Staphylococcus aureus (MSSA) infective endocarditis (IE) in the Spanish National Endocarditis Database (GAMES) and to compare it with antistaphylococcal penicillin (ASP). Methods: Prospective cohort study with retrospective analysis of a cohort of MSSA IE treated with cloxacillin and/or cefazolin. Outcomes assessed were relapse; intra-hospital, overall, and endocarditis-related mortality; and adverse events. Risk of renal toxicity with each treatment was evaluated separately. Results: We included 631 IE episodes caused by MSSA treated with cloxacillin and/or cefazolin. Antibiotic treatment was cloxacillin, cefazolin, or both in 537 (85%), 57 (9%), and 37 (6%) episodes, respectively. Patients treated with cefazolin had significantly higher rates of comorbidities (median Charlson Index 7, P <0.01) and previous renal failure (57.9%, P <0.01). Patients treated with cloxacillin presented higher rates of septic shock (25%, P = 0.033) and new-onset or worsening renal failure (47.3%, P = 0.024) with significantly higher rates of in-hospital mortality (38.5%, P = 0.017). One-year IE-related mortality and rate of relapses were similar between treatment groups. None of the treatments were identified as risk or protective factors. Conclusion: Our results suggest that cefazolin is a valuable option for the treatment of MSSA IE, without differences in 1-year mortality or relapses compared with cloxacillin, and might be considered equally effective

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved