4 research outputs found
Acclimation of Agave potatorum Zucc. micropropagated plants
Agave potatorum Zucc, is a wild species used intensively. The aim was to evaluate the effect of the concentration of mineral salts (MS), IBA and incubation conditions in the rooting stage on the growth of A. potatorum during climatization. The plants came from eighteen treatments resulting from combining three factors: 1) DM concentrations (50, 75, 100%); 2) IBA concentrations (without auxin, 0.5 and 1 mg L-1) and 3) incubation environment (laboratory with fluorescent lighting or greenhouse exposed to solar radiation). The acclimatization process lasted 150 days in the greenhouse, at the end the micropropagated plants in culture medium with 0.5 to 1 mg L-1 of IBA, (MS) at 100% and incubated in the greenhouse showed greater growth.Objective: Agave potatorum Zucc. is an intensively exploited wild plant species. We intend to evaluate how the concentration of mineral salts (MS), indole-butyric acid (IBA), and the incubation conditions affect in vitro-rooted A. potatorum during acclimation.
Design/Methodology/Approach: We conducted 18 treatments that resulted from combining three factors: 1) MS concentrations (50%, 75%, and 100%); 2) IBA concentrations (without auxin, 0.5 mg L-1, and 1 mg L-1); and 3) incubation environments (fluorescent lighting in a laboratory or exposure to solar radiation in a greenhouse). Thirteen plants from each treatment were transplanted into individual pots containing a 1:1 mixture of peat moss and perlite. These were placed in the acclimation greenhouse for 150 days, exposed to changes in solar radiation, starting from 600 µmol m-2 s-1 and conditions of high relative humidity (80-90%), and reaching outdoor conditions with full solar radiation,1400 ±200 µmol m-2 s-1. All in vitro culture plants, both in greenhouse and laboratory, underwent the same environmental and management conditions.
Results: After 150 days of acclimation, plants micropropagated in a culture medium with 0.5 to 1 mg L-1 of IBA, 100% MS, and incubated in a greenhouse showed better growth.
Study limitations/Implications: The in vitro culture protocol was (successfully) modified by providing solar radiation in a greenhouse during the rooting of A. potatorum sprouts.
Findings/Conclusions: Solar radiation during in vitro incubation of A. potatorum favors its acclimation
Calidad de plántula de árboles seleccionados de Leucaena esculenta en sistema agroforestal
Under greenhouse conditions, seedlings quality of Leucaena esculenta selected progenies were evaluated. In this sense, in 2017 the plant growth was analyzing according to tree progenies and age after sowing, AAS, using analysis of variance and mean tests (Duncan, 0.05). The progenies and AAS showed separately significant differences (p ≤ 0.0001) in morphological variables and leaf area. Quality indexes showed significant differences between trees (progenies) and AAS, where tree 9 had the highest Dickson Index (4.54 ± 3.03). According to plant quality indexes, it concludes that seedlings from tree 7 were the best with the highest values of the morphological variables.En condiciones de invernadero se evaluó la calidad de plántulas de progenies selectas de Leucaena esculenta. En este sentido, durante 2017 se estudió el crecimiento de plantas en función de progenies de árboles y edad después de la siembra (DDS) realizando análisis de varianza y pruebas de medias (Duncan, 0.05). Las progenies y los DDS mostraron separadamente diferencias significativas (p ≤ 0.0001) en las variables morfológicas y área foliar. Los índices de calidad fueron diferentes entre árboles (progenies) y DDS, donde el árbol 9 tuvo el valor mayor (4.54 ± 3.03) en el Índice de Dickson. Con los indicadores de calidad de planta se concluye que las progenies del árbol 7 fueron las de mejor calidad con valores mayores de las variables morfológicas
Frutos y semillas de Bursera simplex Rzed. & Calderón en diferentes sitios y estructura arbórea
El territorio del estado de Oaxaca reúne la mayor biodiversidad de México; la vegetación más abundante es la selva baja caducifolia con especies de Bursera de importancia económica y biológica. En el presente estudio se evaluó la composición estructural y el fenotipo de árboles semilleros de Bursera simplex y las características del sitio en que crecen; su producción de frutos y de semillas se describió en función del individuo del cual se recolectaron. Durante 2015, se realizó un muestreo dirigido de 23 unidades muestrales hacia los mejores fenotipos con alta producción de frutos y semillas, ademas se hizo su inventario. Los datos se analizaron mediante índices estructurales y análisis de varianza para comparar la producción de frutos y semillas, en relación al árbol del que se obtuvieron, así como las características del sitio, altitud, pendiente y posición del lugar en el que crecieron los ejemplares. Los de tamaño mayor se asocian a pendientes ≤ 25 % y altitudes ≤ 1 278 m, donde producen 29 259 semillas kg-1. La estructura poblacional es de tipo irregular, con importantes densidades de Bursera simplex asociadas a la exposición oeste; el índice de valor forestal, el índice de valor de importancia y el índice de complejidad afectan las características morfológicas de frutos y semillas
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Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study an international prospective cohort study
We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care. We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care