La nutrición potásica afecta el crecimiento y fotosíntesis en Lilium cultivado en turba ácida

"Lilium (Lilium sp.) es una de las especies ornamentales de mayor valor y se le cultiva para producir flores de corte o plantas en maceta. La incorporación de la floricultura a la tecnología de cultivos sin suelo demanda precisar los niveles óptimos de n

La nutrición potásica afecta el crecimiento y fotosíntesis en "Lilium" cultivado en turba ácida

Lilium (Lilium sp.) is one of the ornamental species with the highest value and is cultivated to produce fresh cut flowers or potted plants. The incorporation of floriculture to crop technology of crops without soil requires the determination of optimum levels of nutrition for each of the required elements. In the present study, the effect of the K concentration in the nutritive solution was evaluated in order to define the concentration that permits the production of Lilium flowers to be cultivated in acidic peat. The solutions in the study consisted of four concentrations of K: 0, 5, 10, and 20 mM. Most of the response variables evaluated, allowed us to define an optimal concentration of K as between and 10 mM, an interval that would be the equivalent of the sufficient nutrient levels. The former was observed in parameters like the diameter of the flower, height of the plant, and total dry weight of the plant. In contrast, excessive levels (20 mM) or deficiencies (0 mM) of K cause a reduction of height and in total dry weight. The increase of the concentration of K in the nutritive solution was related to an increase in the concentration of K in all of the organs, but principally in the root. The greatest net photosynthesis registered in the Young leaves was shown with the supplement of 0 to 20 mM of K, which could be because of a process regulation because of lack of carbohydrates as is suggested by less accumulated biomass.Lilium (Lilium sp.) es una de las especies ornamentales de mayor valor y se le cultiva para producir flores de corte o plantas en maceta. La incorporación de la floricultura a la tecnología de cultivos sin suelo demanda precisar los niveles óptimos de nutrición de cada uno de los elementos requeridos. En el presente estudio se evaluó el efecto de la concentración de K en la solución nutritiva para definir la concentración que permita una producción de flores de Lilium cultivado en turba ácida. Las soluciones en estudio consistieron en cuatro concentraciones de K: 0, 5, 10 y 20 mM. La mayoría de las variables respuesta evaluadas permitió definir una concentración óptima de K entre los 5 y 10 mM, intervalo que sería el equivalente a los niveles de suficiencia nutrimental. Lo anterior fue observado en parámetros como el diámetro de la flor, altura de planta y peso seco total de planta. En contraste, niveles excesivos (20 mM) o de deficiencia (0 mM) de K causaron una reducción en la altura y en el peso seco total. El aumento de la concentración de K en la solución nutritiva estuvo relacionado con un incremento en la concentración de K en todos los órganos, pero principalmente en la raíz. La mayor fotosíntesis neta registrada en las hojas jóvenes se presentó con el suplemento de 0 ó 20 mM de K, lo cual puede deberse a una regulación del proceso por falta de carbohidratos como sugiere la menor biomasa acumulada

Powders, extracts and fractions of leaves of Cestrum nocturnum L. and their antifungal activity over two isolations of Fusarium spp.

One of the main causes that originate considerable postharvest loses during handling and storage of fruits and vegetables is the infection by Fusarium check for this species in other resources . One possible alternative to control postharvest disease originated by fungi in fruits and vegetables is the application of powders and extracts from botanical species with fungicidal properties. The genus Cestrum check for this species in other resources is composed by a great diversity of botanical species with different applications in the traditional medicine, associated with pesticidal and fungicidal activities. The objectives of this research were to obtain aqueous, ethanolic, metanolic, chlorophormic, dichloromethanic and acetonic extracts, evaluating their antifungal activity. Fractions obtained by column chromatography (CC) were evaluated on germination of two isolations of Fusarium from fruits of papaya and red mombin. The fungicidal potential of powders of C. nocturnum at concentrations each 0.5, 1.0, 1.5 and 2.0 g mL-1 and aqueous, methanol, acetone, dichloromethane, chloroform-methanol-water, and ethanol extracts at concentrations each of 12, 25 y 50 mg mL-1 were also evaluated on this two isolations. The parameters evaluated were: mycelial growth, sporulation, germination and also rate of growth. Results showed significative differences in the amount and number mixture of compounds obtained depending on dissolvent applied, time of extraction (24 and 48 h), sterilized and non-sterilized and type of isolation. The greatest number of mixture of compounds (16) was obtained with the acetonic extract. This also showed the greatest number of inhibitory zone of germination in TLC and fractions of CC on Fusarium. The fungicidal activity was different in relation to isolate and treatment applied. Powders stimulated sporulation and germination in both isolates; however, they did inhibit micelial growth in red mombin isolate. For both isolates, only the methanol extract of C. nocturnum at 25 mg mL-1 inhibited micelial growth and sporulation. Rate of growth was higher in red mombin isolate.Una de las principales causas de pérdidas postcosecha de frutas y hortalizas es la pudrición causada por Fusarium check for this species in other resources spp. Una de las posibles alternativas en el control de estas enfermedades es la utilización de especies botánicas con propiedades fungicidas ya sea en polvos o extractos. El género Cestrum check for this species in other resources se compone de una diversidad de especies con diferentes usos en la medicina tradicional, asociándose también con actividad insecticida y fungicida. Los objetivos de esta investigación fueron obtener extractos acuosos, etanólicos, metanólicos, clorofórmicos, diclorometánicos y acetónicos de C. nocturnum y evaluar su actividad antifúngica. Las fracciones obtenidas por cromatografía en columna (CC) fueron evaluadas sobre la germinación de dos aislamientos de Fusarium obtenidos de frutos de papaya y ciruela mexicana ( Spondias purpurea check for this species in other resources ). Asimismo, se evaluó el potencial fungicida de polvos de C. nocturnumen concentraciones de 0,5; 1,0; 1,5 y 2,0 g mL-1 y de extractos de C. nocturnum en concentraciones de 12, 25 y 50 mg mL-1 en estos dos aislamientos. Las variables estudiadas fueron crecimiento micelial, esporulación y germinación conidial, así como la tasa de crecimiento. Los resultados mostraron que hubo diferencias importantes en la cantidad y número de mezclas de componentes obtenidos en función del disolvente utilizado, tiempo de extracción (24 y 48 h), esterilizado y no esterilizado, y aislamiento evaluado. El mayor número de mezclas de componentes obtenidos (16) fue con los extractos acetónicos. Éste a su vez mostró el mayor número de zonas de inhibición de la germinación por CCF y fracciones de CC en los aislamientos de Fusarium. Los polvos de C. nocturnumestimularon la formación de conidios y germinación en ambos aislamientos, sin embargo, inhibieron el crecimiento micelial en el aislamiento de ciruela mexicana. En ambos aislamientos únicamente el extracto metanólico a 12 mg mL-1 de C. nocturnum inhibió tanto el crecimiento micelial como la esporulación. En relación a la tasa de crecimiento, ésta fue mayor en el aislamiento de ciruela mexicana

Delayed colorectal cancer care during covid-19 pandemic (decor-19). Global perspective from an international survey

Background The widespread nature of coronavirus disease 2019 (COVID-19) has been unprecedented. We sought to analyze its global impact with a survey on colorectal cancer (CRC) care during the pandemic. Methods The impact of COVID-19 on preoperative assessment, elective surgery, and postoperative management of CRC patients was explored by a 35-item survey, which was distributed worldwide to members of surgical societies with an interest in CRC care. Respondents were divided into two comparator groups: 1) ‘delay’ group: CRC care affected by the pandemic; 2) ‘no delay’ group: unaltered CRC practice. Results A total of 1,051 respondents from 84 countries completed the survey. No substantial differences in demographics were found between the ‘delay’ (745, 70.9%) and ‘no delay’ (306, 29.1%) groups. Suspension of multidisciplinary team meetings, staff members quarantined or relocated to COVID-19 units, units fully dedicated to COVID-19 care, personal protective equipment not readily available were factors significantly associated to delays in endoscopy, radiology, surgery, histopathology and prolonged chemoradiation therapy-to-surgery intervals. In the ‘delay’ group, 48.9% of respondents reported a change in the initial surgical plan and 26.3% reported a shift from elective to urgent operations. Recovery of CRC care was associated with the status of the outbreak. Practicing in COVID-free units, no change in operative slots and staff members not relocated to COVID-19 units were statistically associated with unaltered CRC care in the ‘no delay’ group, while the geographical distribution was not. Conclusions Global changes in diagnostic and therapeutic CRC practices were evident. Changes were associated with differences in health-care delivery systems, hospital’s preparedness, resources availability, and local COVID-19 prevalence rather than geographical factors. Strategic planning is required to optimize CRC care