Silicon application induces changes C:N:P stoichiometry and enhances stoichiometric homeostasis of sorghum and sunflower plants under salt stress

Abstract

Beneficial effects of silicon (Si) on growth have been observed in some plant species, reportedly due to stoichiometric changes of C, N, and P. However, little is known about the effects on the stoichiometric relationships between C, N, and P when silicon is supplied via different modes in sorghum and sunflower plants under salt stress conditions. Therefore, the current study was performed to investigate the impact of differing modes of Si supply on shoot biomass production and C:N:P stoichiometry in sorghum and sunflower plants under salt stress. Two experiments were performed in a glass greenhouse using the strong Si-accumulator plant sorghum, as well as the intermediate type Si-accumulator sunflower, both of which were grown in pots filled with washed sand. Plant species were cultivated for 30 days in the absence or presence of salt stress (0 or 100 mM) and supplemented with one of four Si treatments: control plants (without Si), 28.6 mmol Si L −1 via foliar application, 2.0 mmol Si L −1 via nutrient solution, and combined application of foliar and nutrient solution, each group with five replications. The results revealed that supplied Si modified the C, N, and P concentrations, thereby enhancing the C:N:P stoichiometry and shoot dry matter of sorghum and sunflower plants under salt stress. Both application of Si via nutrient solution, as well as combined application via foliar and nutrient solution, increased the C:N ratio in both plant species under salt stress, but in sorghum plants decreased the C:P and N:P ratios and increased the shoot biomass production by 39%, while in sunflower plants increased the C:P and N:P ratios and increased the shoot biomass production by 24%. Our findings suggest that salt stress alleviation by Si impacts C:N:P stoichiometric relationships in a variable manner depending on the ability of the species to accumulate Si, as well as the route of Si administration.

Root- and foliar-applied silicon modifies C: N: P ratio and increases the nutritional efficiency of pre-sprouted sugarcane seedlings under water deficit

“…The C concentrations decline in leaf tissue by has also been reported in wheat plants [13] and Phragmites australis [14] without water deficit, and in sorghum plants grown in saline solution [45]. Given our results, it also occurs in sugarcane seedlings under suitable conditions and short and long-term WDs.…”

Silicon modifies C:N:P stoichiometry, and increases nutrient use efficiency and productivity of quinoa

“…The energy cost for incorporating Si in structural compounds is less than the inclusion of C in organic compounds, due to the intrinsic permeability of the lipid bilayers 33 , also contributing to better plant growth. The decreasing C levels in different plant organs have not only been confirmed under normal growing conditions but also in plants grown under abiotic stress conditions, such as salinity 12 , 34 and water deficit 35 , which induces greater energy expenditure by the plant and Si can mitigate this consumption, benefiting these plants.…”

Absorción de agua y nutrientes y respuesta fisiológica de plantas halofitas y glicofitas bajo condiciones de estrés salino

“…Recientemente, Calero Hurtado et al (2020) demostraron que la aplicación de Si inhibe la entrada de Na + mientras que estimulaba la entrada de K + y Ca 2+ , mejorando el crecimiento de las plantas en condiciones salinas.…”

“…Glucosinolatos: Se trata de compuestos del metabolismo secundario casi exclusivos de las plantas del orden Capparales. Han sido ampliamente estudiados en diferentes brásicas relacionándolos con buenas propiedades para la salud humana (Verkerk et al, 2009), destacando especialmente las propiedades antiinflamatorias y el efecto protector frente a varios tipos de cáncer (Capuano et al, 2017;Arumugam and Razis, 2018;Bayat Mokhtari et al, 2018;Soundararajan and Kim, 2018;García-Ibañez et al, 2020).…”

“…Este efecto estimulador del riego salino sobre el contenido en glucosinolatos ha sido previamente observado y puede constituir un elemento reclamo a nivel comercial. Por un lado, por los efectos beneficiosos atribuidos al consumo de productos ricos en glucosinolatos (Capuano et al, 2017). Un ejemplo de este reclamo comercial lo encontramos en el cultivar Beneforte que emplea como reclamo publicitario el ser un cultivar con elevado contenido en glucorrafanina (Quadram Institute, 2013).…”