Synergistic effects of abiotic stresses in plants: a case study of nitrogen limitation and saturating light intensity inArabidopsis thaliana

Abstract

Under natural conditions, plants are regularly exposed to combinations of stress factors. A common example is the conjunction between nitrogen (N) deficiency and excess light. The combined effect of stress factors is often ignored in studies using controlled conditions, possibly resulting in misleading conclusions. To address this issue, the present study examined the physiological behavior of Arabidopsis thaliana under the effect of varying nitrogen levels and light intensities. The joint influence of low N and excess light had an adverse effect on plant growth, chlorophyll and anthocyanin concentrations, photochemical capacity and the abundance of proteins involved in carbon assimilation and antioxidative metabolism. In contrast, no adverse physiological responses were observed for plants under either nitrogen limitation or high light (HL) intensity conditions (i.e. single stress). The underlying mechanisms for the increased growth in conditions of HL and sufficient nitrogen were a combination of chlorophyll accumulation and an increased number of proteins involved in C3 carbon assimilation, amino acids biosynthesis and chloroplast development. In contrast, combined stress conditions shifts plants from growth to survival by displaying anthocyanin accumulation and an increased number of proteins involved in catabolism of lipids and amino acids as energy substrates. Ultimately switching plants development from growth to survival. Our results suggest that an assessment of the physiological response to the combined effect of multiple stresses cannot be directly extrapolated from the physiological response to a single stress. Specifically, the synergistic interaction between N deficiency and saturating light in Arabidopsis plants could not have been modeled via only one of the stress factors.

High Nitrate or Ammonium Applications Alleviated Photosynthetic Decline of Phoebe bournei Seedlings under Elevated Carbon Dioxide

“…Plant growth is governed by the balance of carbon assimilation and respiration. The joint influence of low nitrogen and excess light had an adverse effect on plant growth; in contrast, no adverse physiological responses were observed for plants under either nitrogen limitation or high light intensity conditions [25]. Similarly, in this study, P. bournei seedlings that received moderate nitrate applications under eCO 2 showed the phenomenon of photosynthetic decline, which is consistent with the findings reported by Han et al [35].…”

“…The application of nitrogen is an important regulatory measure to improve plant photosynthetic characteristics and to promote plant growth [24]. For example, nitrogen regulates plant responses to different light intensities [25]. However, the effect of nitrogen nutrition on the adaptation of photosynthesis under eCO 2 depends on the supply level and is regulated by the source-sink relationship of plants [26,27].…”

Validation of an Enzyme-Driven Model Explaining Photosynthetic Rate Responses to Limited Nitrogen in Crop Plants

“…To understand the total N content and the N allocations to the photosynthetic machinery, which contribute to the diversity of various photosynthetic capacities, a great deal of research is required. The reduction in leaf N mostly aggravates photosynthetic acclimation to eCO 2 (Halpern et al, 2019), while low N availability reduces the photosynthetic capacity by reducing the C assimilation proteins, as well as Rubisco (Cohen et al, 2019b). Finally, both low leaf N and eCO 2 may have adverse impacts on the expression of Rubisco, which stimulates eCO 2 (Cohen et al, 2019a).…”

Nitrogen supply and shading affect morphology and composition of the essential oil in marigold (Tagetes erecta L.)

“…Indeed, N deficiencies and excessive light are a common combination of stress factors that plants have to face under natural conditions. When exposed to high light intensity environments, plants can exhibit symptoms, such as chlorophyll degradation and growth inhibition, which are the result of secondary oxidative stress derived from an overload of the photosynthetic apparatus (Cohen et al, 2019). The adverse effect of combining low nitrogen fertilisations with high light intensity conditions (i.e.…”

“…The adverse effect of combining low nitrogen fertilisations with high light intensity conditions (i.e. potentially acute photodamage) is inevitably reflected in a reduction in growth and productivity (Cohen et al, 2019). Thus, light and N fertilisers influence growth and development of plants, and each plant species may display particular responses to fluctuations in light intensities, while a balanced nutrient supply tends to favour plant development (De Oliveira et al, 2019).…”