Application of phytohormones as attenuators of salt stress in Tropaeolum majus L. (Tropaeolaceae)

The salinity of the soil and irrigation water is one of the great challenges of agriculture. Salinity can have harmful effects on physiological processes and plant growth, including Tropaeolum majus L. (Tropaeolaceae). The application of phytohormones can be a strategy to mitigate these effects. The aim of this study was to evaluate the application of jasmonic acid, salicylic acid, cytokinin and polyamine as attenuators of salt stress in T. majus. Three levels of salt stress were used: 0 mM NaCl (no stress), 50 mM NaCl (moderate stress) and 100 mM NaCl (severe stress). Four phytohormones and a control treatment were used: control (deionized water), jasmonic acid (200 µM), salicylic acid (2 mM), cytokinin (6-benzylaminopurine – 10 µM) and polyamine (spermine – 1 mM). Growth and gas exchange parameters were evaluated. Applied in conditions of moderate salt stress, all the phytohormones were efficient in improving plant height and leaf area (except salicylic acid); cytokinin and polyamine improved the number of flowers as well as gs, A and iCE; jasmonic acid improved the stem dry mass and total dry mass. In relation to severe salt stress, applications of jasmonic acid and polyamine were efficient in improving plant height; cytokinin improved leaf dry mass as well as gs, A, E, WUE, iWUE and iCE. The application of cytokinin, polyamine and jasmonic acid can be used to mitigate moderate salt stress in T. majus.

Capuchinha (tropaeolum majus) compostos bioativos e sua funcionalidade no organismo

Flores comestíveis (PANC), são cada vez mais utilizadas no preparo de refeições, pois possuem potencial benéfico à saúde humana. A capuchinha (Tropaeolum majus) é uma flor reconhecida por suas propriedades antioxidantes e alto teor de compostos fenólicos. O presente estudo teve como objetivo avaliar o perfil de compostos bioativos, nutricionais na saúde humana, tais como carotenoides, compostos fenólicos, flavonoides e antocianinas, em flores comestíveis da espécie (Tropaeolum majus) através da aplicação da metodologia de revisão descritiva. Através desta revisão descritiva buscou-se levantar dados sobre os efeitos dos compostos bioativos da Capuchinha no organismo dos seres humanos. A busca de bibliografias publicadas ocorreu nas bases de dados Scielo, Google Acadêmico e World Wide Science entre os anos de 2004 a 2020 através de descritores “Capuchinha”, “compostos bioativos”, compostos fenólicos”, “antocianinas” e "carotenoides", “Tropaeolum majus”, “flores comestíveis", no total foram 27 artigos nos idiomas português e inglês. Após a leitura e avaliação 20 artigos foram selecionados. Nesse contexto, conclui-se que a capuchinha (Tropaeolum majus) representa uma categoria de alimento promissora para maior utilização na alimentação por suas características funcionais ou sensoriais.

Evaluación de citotoxicidad del isotiocianato de bencilo de Troapeolum majus L. en líneas tumorales de mama

El mastuerzo (Tropaeolum majus L.) es una planta originaria de Perú, México y partes de América Central; en el Perú, era usada desde tiempos muy antiguos, por nuestros antepasados, para combatir distintas enfermedades. Entre sus componentes se encuentra la glucotropaeolina, que, al ser hidrolizado, forma el bencil isotiocianato (BIT) que fomenta la apoptosis celular. Debido a ello, se tuvo como objetivo; primero, evaluar el efecto citotóxico del isotiocianato de bencilo del mastuerzo expuestas a microgravedad sobre el cultivo in vitro de la línea tumoral MCF-7 de cáncer de mama. Se utilizaron extractos de isotiocianato de bencilo de mastuerzo de la planta cultivada en forma natural (T1) y; la segunda, expuesta a microgravedad en la etapa de germinación (T2), comparándose con el producto comercial (BI), la viabilidad celular se efectuó a través de la técnica del MTT realizándose diluciones de 0, 20, 40, 60, 80 y 100 uM del extracto expuesto al cultivo de células tumorales de tipo MCF-7 cáncer de mama por un tiempo de 12, 24, 48, y 60 horas lecturándose en un lector de placas de ELISA a 570 nm. Se obtuvo una DL50 entre 22,56 ± 3,24 a 19,97 ± 2,52 a las 60 horas, valores similares a las 48 horas comparadas con el control benzil de isiocianato (BI). En conclusión, no se evidencia diferencia en el efecto de la dosis letal media de todos los tratamientos en las 48 y 60 horas de incubación frente al benzil isiocianato (BI). El efecto máximo de inhibición en todas las concentraciones es apreciable a las 60 horas de incubación, afirmándose que no existe una diferencia significativa de sus actividades biológicas entre T1 y T2.

Continuous Lighting and High Daily Light Integral Enhance Yield and Quality of Mass-Produced Nasturtium (Tropaeolum majus L.) in Plant Factories

Nasturtium (Tropaeolum majus L.), as a medicinal plant, has a high phenolic content in its leaves and flowers. It is often used in salads as a dietary vegetable. Attracting strong demand, it could be a good candidate crop for a plant factory with artificial lighting (PFAL) that can achieve the mass production of high-quality crops with high productivity by regulating environmental conditions such as light. In this study, two experiments were conducted to investigate the effects of continuous lighting (CL) and different daily light integrals (DLIs) under CL on the growth, secondary metabolites, and light use efficiency (LUE) of nasturtium, all of which are essential in the successful cultivation in PFALs. In Experiment 1, two lighting models, the same DLI of 17.3 mol m-2 d-1 but different light periods (24 and 16 h) with different light intensities (200 and 300 µmol m−2 s−1, respectively), were applied to nasturtium. The results showed that leaf production, secondary metabolites, and LUE were higher under the 24-h CL treatment than under the 16-h non-CL treatment. In Experiment 2, three DLI levels (17.3, 25.9, and 34.6 mol m-2 d-1) under the CL condition were applied. The results showed that the growth parameters were positively correlated with the DLI levels under CL. The lowest DLI had the highest LUE. We conclude that the mass production of nasturtium under CL in PFALs is feasible, and the yield increases as DLI increases from 17.3 to 34.6 mol m-2 d-1 under CL without causing physiological stress on plants.