Analysis of Metabolomic Changes in Lettuce Leaves under Low Nitrogen and Phosphorus Deficiencies Stresses

Abstract

Nitrogen and phosphorus limitation affect the growth, development, and productivity of lettuce, which exert a marked influence on metabolites. To compare the influence of low-nitrogen and low-phosphorus stresses on various metabolites of lettuce leaves, experiments were performed under three conditions of treatment—low-nitrogen stress, low-phosphorus stress, and normal samples. Metabolomic analyses were conducted based on ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. Principle components analysis yielded distinctive clustering information among the holistic samples; fold change analysis, t-test and orthogonal partial least square discriminant analysis were used for the selection of metabolic biomarkers. Ten pathways were selected which were significantly enriched by metabolic biomarkers. Metabolic biomarkers were screened by fold change (FC) value, p-value and variable importance in the projection (VIP) value, low-nitrogen and low-phosphorus stresses caused an increase in 16 metabolites (FC > 2, p-value < 0.05, VIP > 1) and a decrease in 26 metabolites (FC < 0.5, p-value < 0.05, VIP > 1). Outside of these, our results showed that inositol, p-hydroxybenzoic acid, stachyose, dinoseb, and 7, 8-dihydroxycoumarin increase in low-nitrogen stress samples. Low-phosphorus stress caused accumulation of citrate, isocitrate, l-5-oxoproline, succinate, and histamine, which may be considered potential metabolic biomarkers. The metabolites could be used to monitor the nitrogen and phosphorus status of lettuce and to guide appropriate fertilization regimens.

Intraspecific Variability Largely Affects the Leaf Metabolomics Response to Isosmotic Macrocation Variations in Two Divergent Lettuce (Lactuca sativa L.) Varieties

“…Our current understanding of how the controlled manipulation of multiple mineral elements interacts on a pre-existing phytochemical diversity in plants is very limited, also because, for instance, different studies have been carried out in relation to an exposure to abiotic stress conditions [51][52][53][54]. The analysis of the effects on the NS in relation to the different colored genotypes provided interesting insights.…”

Integrated transcriptomic and metabolomic analyses reveal key metabolic pathways in response to potassium deficiency in coconut (Cocos nucifera L.) seedlings

“…Watanabe et al (2020) found that the levels of anti-stress substances and amino acid substitutes increased under N deficiency, and the metabolism of benzoic acid, erucic acid, and glucuronate in rice leaves was related to low-P stress. Gao et al (2020) found that p-hydroxybenzoic acid, inositol, dinol, and stachyose levels increased in lettuce leaves under N deficiency.…”

Analysis of Metabolomic Changes in Xylem and Phloem Sap of Cucumber under Phosphorus Stresses

“…The treatment of low phosphorus stress was to reduce H 2 PO 4 − in nutrient solution to 0.3125, 0.625 and 0.9375 mmol•L −1 respectively; the treatment method of high phosphorus stress was to increase H 2 PO 4 − in nutrient solution to 1.875 mmol•L −1 . The greenhouse temperature ranged from 18-35 • C. The average daily irradiation was 13.2 MJ/m 2 , and the average natural light duration was 5.13 h. After two weeks, samples were taken between 10:00 and 12:00 am to minimize diurnal effects on metabolite concentration [5]. Qualitative and quantitative analysis was performed with GC-MS after the sampling was completed.…”

“…However, before the external characteristics of plants change, in order to resist the harm caused by phosphorus stress, plants use their metabolic ability to produce a large number of small molecular compounds and restructure their metabolic network to maintain necessary metabolism. Therefore, at the molecular level, the method of detecting metabolic biomarkers can quickly and efficiently reflect whether the phosphorus nutrient supply level of plants is normal, and confirm the nutritional status of plants as soon as possible when the nutrient deficiency can still be remedied [5], and guide the reasonable fertilization scheme, which has great practical significance.…”

“…The results implied that the phosphorus stress severely disturbed the metabolism of minerals and metabolites in tea plants, which influenced the yield and quality of tea [13]. Gao et al compared the effects of low nitrogen and phosphorus deficiencies stresses on various metabolites in lettuce leaves based on metabolomics technology, and preliminarily investigated the changes of potential metabolic biomarkers under low nitrogen and phosphorus stresses [5].…”