scholarly journals Multi-omics analysis of xylem sap uncovers dynamic modulation of poplar defenses by ammonium and nitrate

2021 ◽  
Author(s):  
Karl H. Kasper ◽  
Ilka N Abreu ◽  
Kirstin Feussner ◽  
Krzysztof Zienkiewicz ◽  
Cornelia Herrfurth ◽  
...  
Keyword(s):  
Xylem Sap ◽  
Pipecolic Acid ◽  
Functional Categories ◽  
N Nutrition ◽  
Dynamic Modulation ◽  
N Supply ◽  
Low Concentrations ◽  
Biotrophic Fungi ◽  
Ammonium Nutrition ◽  
Transcriptional Landscape

Xylem sap is the major transport route for nutrients from roots to shoots. Here, we investigated how variations in nitrogen (N) nutrition affected the metabolome and proteome of xylem sap, growth of the xylem endophyte Brennaria salicis and report transcriptional re-wiring of leaf defenses in poplar (Populus x canescens). We supplied poplars with high, intermediate or low concentrations of ammonium or nitrate. We identified 288 unique proteins in xylem sap. About 85% of the xylem sap proteins were shared among ammonium- and nitrate-supplied plants. The number of proteins increased with increasing N supply but the major functional categories (catabolic processes, cell wall-related enzymes, defense) were unaffected. Ammonium nutrition caused higher abundances of amino acids and carbohydrates, while nitrate caused higher malate levels in xylem sap. Pipecolic acid and N-hydroxy-pipecolic acid increased whereas salicylic acid and jasmonoyl-isoleucine decreased with increasing N nutrition. Untargeted metabolome analyses revealed 2179 features in xylem sap, of which 863 were differentially affected by N treatments. We identified 122 metabolites, mainly from specialized metabolism of the groups of salicinoids, phenylpropanoids, phenolics, flavonoids, and benzoates. Their abundances increased with decreasing N. Endophyte growth was stimulated in xylem sap of high N- and suppressed in that of low N-fed plants. The drastic changes in xylem sap composition caused massive changes in the transcriptional landscape of leaves and recruited defense pathways against leaf feeding insects and biotrophic fungi, mainly under low nitrate. Our study uncovers unexpected complexity and variability of xylem composition with consequences for plant defenses.

scholarly journals Nitrogen Supply Influences Carbohydrate Partitioning of Pepper Seedlings and Transplant Development

1991 ◽  
Vol 116 (6) ◽  
pp. 995-999 ◽  
Author(s):  
Beny Aloni ◽  
Tamara Pashkar ◽  
Lea Karni ◽  
Jaleh Daie
Keyword(s):  
Soluble Sugar ◽  
Leaf Age ◽  
Carbohydrate Partitioning ◽  
N Nutrition ◽  
Post Transplant ◽  
Nitrogen Levels ◽  
Unit Leaf ◽  
Leaf Chlorophyll ◽  
N Supply ◽  
Root Shoot Ratio

We investigated the effects of N nutrition on growth and carbohydrate partitioning of pepper (Capsicum annuum L., cv. Maor) seedlings in the greenhouse and on their subsequent recovery and development after transplanting. Seedlings received 0, 30, 100, or 200 mg N/liter for 14 days, after which they were transplanted and received 100 mg N/liter. Nitrogen levels below 100 mg·liter−1 inhibited shoot growth and leaf chlorophyll content; both were severely inhibited in the absence of supplemental N. Root growth had a negative relation with N supply; an enhanced root: shoot ratio was observed under low-N regimes. On a unit-leaf-area basis, CO2 fixation was not affected when N was present; however, it was greatly inhibited in the absence of N. Changes in the leaf starch and soluble sugar concentrations occurred as a function of N supply and leaf age. In the roots, low N led to lower sucrose and higher levels of hexose and starch. More sucrose was transported and accumulated into leaf veins of low-N tissue. Exogenously supplied 14C-labeled sucrose was rapidly converted into starch in the low-N tissue. Seedlings that received 100 mg N/liter had the highest post-transplant growth rate and flowered earlier. Carbohydrate status of young pepper seedlings influenced their post-transplant recovery. Optimal N supply is essential for full recovery and development of transplants.

The plant immunity inducer pipecolic acid accumulates in the xylem sap and leaves of soybean seedlings following Fusarium virguliforme infection

Plant Science ◽  
2016 ◽  
Vol 243 ◽  
pp. 105-114 ◽  
Author(s):  
Nilwala S. Abeysekara ◽  
Sivakumar Swaminathan ◽  
Nalini Desai ◽  
Lining Guo ◽  
Madan K. Bhattacharyya
Keyword(s):  
Plant Immunity ◽  
Xylem Sap ◽  
Pipecolic Acid ◽  
Fusarium Virguliforme ◽  
Soybean Seedlings

scholarly journals Polar lipids are linked to nanoparticles in xylem sap of temperate angiosperm species

2021 ◽  
Author(s):  
Xinyi Guan ◽  
H Jochen Schenk ◽  
Mary R. Roth ◽  
Ruth Welti ◽  
Julia Werner ◽  
...  
Keyword(s):  
Lipid Composition ◽  
Xylem Sap ◽  
Seasonal Difference ◽  
Polar Lipids ◽  
Contamination Control ◽  
Low Concentrations ◽  
Angiosperm Species ◽  
Liquid And Solid Phases ◽  
Control Samples ◽  
Xylem Conduits

Xylem sap of angiosperm species has been found to include low concentrations of polar lipids and nanoparticles, including surfactant-coated nanobubbles. Although the nanoparticles have been suggested to consist of polar lipids, no attempt has been made to determine if nanoparticle and lipid concentrations are related. Here, we examined concentrations of nanoparticles and lipids in xylem sap and contamination control samples of six temperate angiosperm species with a NanoSight device and based on mass spectrometry. We found (1) that the concentration of nanoparticles and lipids were both diluted when an increasing amount of sap was extracted, (2) that their concentrations were significantly correlated in three species, (3) that their concentrations were affected by vessel anatomy, and (4) that concentrations of nanoparticles and lipids were very low in contamination-control samples. Moreover, there was little seasonal difference, no freezing-thawing effect on nanoparticles, and little seasonal variation in lipid composition. These findings indicate that lipids and nanoparticles are related to each other, and largely do not pass interconduit pit membranes. Further research is needed to examine the formation and stability of nanoparticles in xylem sap in relation to lipid composition, and the complicated interactions among the gas, liquid, and solid phases in xylem conduits.

scholarly journals Transcriptional Landscape of Ectomycorrhizal Fungi and Their Host Provides Insight into N Uptake from Forest Soil

mSystems ◽  
2022 ◽  
Author(s):  
Carmen Alicia Rivera Pérez ◽  
Dennis Janz ◽  
Dominik Schneider ◽  
Rolf Daniel ◽  
Andrea Polle
Keyword(s):  
Soil Solution ◽  
Molecular Mechanisms ◽  
N Uptake ◽  
Dynamic Environment ◽  
Tree Roots ◽  
N Nutrition ◽  
Nitrate Availability ◽  
N Acquisition ◽  
Insight Into ◽  
Transcriptional Landscape

Although EMF are well known for their role in supporting tree N nutrition, the molecular mechanisms underlying N flux from the soil solution into the host through the ectomycorrhizal pathway remain widely unknown. Furthermore, ammonium and nitrate availability in the soil solution is subject to frequent oscillations that create a dynamic environment for the tree roots and associated microbes during N acquisition.

Effects of temperature and nitrogen nutrition on the accumulation of gliadins analysed by RP-HPLC

2001 ◽  
Vol 28 (12) ◽  
pp. 1197 ◽  
Author(s):  
Catherine Daniel ◽  
Eugen Triboï
Keyword(s):  
Field Experiments ◽  
Nitrogen Nutrition ◽  
Critical Role ◽  
Dynamic Allocation ◽  
N Nutrition ◽  
N Supply ◽  
Rp Hplc ◽  
Sequential Extraction Method ◽  
Effects Of Temperature ◽  
Final Composition

The gliadin content and composition at harvest play a critical role in governing wheat flour properties and uses. The effects of two major environmental factors, temperature and nitrogen (N) supply, on gliadin accumulation were studied using a sequential extraction method coupled with RP–HPLC separation, in order to understand the variations observed at harvest. The thermal effects after anthesis were studied at canopy level in transparent climate tunnels in 1997 and 1998 under natural light. The N effects were studied in field experiments in 1997. An increase in temperature after anthesis induced an increase in the rate of gliadin accumulation per day, and a decrease in the duration of accumulation in days. The effects of the temperature were greater on the α, β-gliadins than on the ω- and γ-gliadins. Increased N nutrition increased the rate and duration of accumulation both in days and degree-days (˚Cd). The level of N nutrition before anthesis governed the effects of N supply at anthesis. The accumulation of ω-gliadins was relatively more affected by the N supply than the α-, β- and γ-gliadins. The final composition of gliadins was a function of the rate of accumulation and of the duration of synthesis, determined by the dates of onset and cessation of synthesis. We concluded that the dynamic allocation of N between different gliadin fractions, described in terms of thermal time, could be useful for modelling gliadin content and composition of wheat.

scholarly journals Ethylene Evolution by Tomatoes Stressed by Ammonium Nutrition

1994 ◽  
Vol 119 (4) ◽  
pp. 706-710 ◽  
Author(s):  
Allen V. Barker ◽  
Kathleen M. Ready
Keyword(s):  
Lycopersicon Esculentum ◽  
Concomitant Increase ◽  
Ethylene Evolution ◽  
N Accumulation ◽  
Causal Factors ◽  
N Nutrition ◽  
Ammonium Accumulation ◽  
Naturally Occurring ◽  
Blossom End Rot ◽  
Ammonium Nutrition

Studies of ethylene evolution by tomato (Lycopersicon esculentum Mill.) fruit were conducted with plants receiving NH4-N or NO3-N nutrition. Fruit of plants grown with NH4-N had a higher occurrence of blossom-end rot (BER), higher NH4-N concentrations, and higher ethylene evolution rates than fruit from plants grown with NO3-N. Fruit of plants grown with NO3-N showed no enhancement in ethylene evolution with BER development. Fertilizing these plants with Ca(NO3)2 doubled the average Ca concentration of fruit and restricted BER development. Ammonium suppressed Ca accumulation in fruit relative to those grown with NO3-N. Ethylene evolution increased as fruit from plants receiving NO3-N ripened, but without a concomitant increase in NH4-N concentrations in the fruit. Ammonium accumulation in fruit induced BER and enhanced ethylene evolution. These relationships were unique, for NH4-N accumulation did not seem to be a naturally occurring phenomenon in ripening fruit or in fruit that have BER arising from other causal factors.

A STUDY OF ONIONS GROWN IN MICROPLOTS ON THREE ORGANIC SOILS EACH CONTAINING FOUR LEVELS OF COPPER

1983 ◽  
Vol 63 (2) ◽  
pp. 221-228 ◽  
Author(s):  
S. P. MATHUR ◽  
R. B. SANDERSON ◽  
A. BELANGER ◽  
M. VALK ◽  
E. KNIBBE ◽  
...  
Keyword(s):  
Key Words ◽  
Crop Yield ◽  
Crop Yields ◽  
Background Level ◽  
Organic Soils ◽  
Treatment Level ◽  
Surface Layers ◽  
N Nutrition ◽  
N Supply ◽  
Four Levels

To assess effects of soil Cu on the yield and nutrition of a crop, onions (Allium cepa ’Autumn Spice’) were grown in field microplots at sites A (peat), B (muck) and C (mucky peat). The surface layers (0–20 cm) of the plots contained four levels of residual fertilizer Cu up to 1200 ppm (wt/wt) at sites A and B and up to 600 ppm at site C. The highest Cu treatment at sites A and B contained about 4–6 times the Cu required for mitigating the excessive decomposition and subsidence of such organic soils. Neither the Cu treatment level nor the total soil Cu concentration influenced crop yields at sites B or C. Crop yield responded positively to the two highest Cu treatment levels at site A where the background level of soil Cu was the lowest among the three sites. The Cu concentrations in the crop at all sites were below the level considered to be phytotoxic (20 ppm). Fe and Zn contents in plants were also not depressed by higher Cu concentrations except for foliar Fe on the highest Cu treatment plots at site A. These plots were intrinsically poorer in Fe than those treated with lesser Cu. Foliar Fe:Cu and Zn:Cu ratios were also lowest, but not below adverse levels, for the highest Cu treatment levels at sites A and B, respectively. Even the highest levels of soil Cu did not reduce N supply for, or N nutrition of, the onion crop, or alter the crop concentrations or uptakes of P, K, Ca, Mg and Mn. Key words: Copper, onions, subsidence, histosol, muck, peat

On-farm soil N supply and N nutrition in the rice–wheat system of Nepal and Bangladesh

1999 ◽  
Vol 64 (3) ◽  
pp. 273-286 ◽  
Author(s):  
C Adhikari ◽  
K.F Bronson ◽  
G.M Panuallah ◽  
A.P Regmi ◽  
P.K Saha ◽  
...  
Keyword(s):  
Soil N ◽  
N Nutrition ◽  
N Supply ◽  
On Farm

Plant—atmosphere exchange of ammonia

1995 ◽  
Vol 351 (1696) ◽  
pp. 261-278 ◽  
Keyword(s):  
Compensation Point ◽  
Controlled Environment ◽  
Single Model ◽  
Model Concept ◽  
N Nutrition ◽  
N Supply ◽  
Resistance Approach ◽  
Leaf Tissues ◽  
Small X

The results of recent controlled environment and micrometeorological measurements of NH 3 fluxes are presented to highlight the processes controlling NH 3 plant-atmosphere exchange. The presence of NH +4 in leaf tissues results in the existence of an NH 3 ‘compensation point’ concentration for substomatal tissues (x s ), so that both emission and deposition are possible from stomata. In addition, NH 3 may deposit efficiently on to leaf cuticles, short-circuiting any stomatal emission, so that a ‘canopy compensation point’ (X c ) may be defined that is smaller than X s . Ammonia is generally deposited to nitrogen limited ecosystems, indicating a small X s and small leaf cuticle resistance ( R w ). In contrast, fluxes over croplands are typically bidirectional and may reflect a larger X s as a consequence of greater N supply. The paper discusses the processes defining (humidity, acidic pollutants) and X s (plant phenology, species, N nutrition) and proposes a new resistance approach, which integrates X s and R w into one model. Estimating long term bidirectional NH 3 fluxes is still uncertain, though it is now possible to apply a single model concept to a range of ecosystem types and satisfactorily infer NH 3 fluxes over diurnal time scales.

scholarly journals Interaction Effects of Nitrogen Rates and Forms Combined With and Without Zinc Supply on Plant Growth and Nutrient Uptake in Maize Seedlings

2021 ◽  
Vol 12 ◽  
Author(s):  
Yanfang Xue ◽  
Wei Yan ◽  
Yingbo Gao ◽  
Hui Zhang ◽  
Liping Jiang ◽  
...  
Keyword(s):  
Plant Growth ◽  
Nutrient Uptake ◽  
Sufficient Conditions ◽  
Molar Ratio ◽  
Shoot Biomass ◽  
Root Surface Area ◽  
Maize Seedlings ◽  
N Nutrition ◽  
N Supply ◽  
Zn Accumulation

Previous studies have shown that zinc (Zn) accumulation in shoot and grain increased as applied nitrogen (N) rate increased only when Zn supply was not limiting, suggesting a synergistic effect of N on plant Zn accumulation. However, little information is available about the effects of different mineral N sources combined with the presence or absence of Zn on the growth of both shoot and root and nutrient uptake. Maize plants were grown under sand-cultured conditions at three N forms as follows: NO3– nutrition alone, mixture of NO3–/NH4+ with molar ratio of 1:1 (recorded as mixed-N), and NH4+ nutrition alone including zero N supply as the control. These treatments were applied together without or with Zn supply. Results showed that N forms, Zn supply, and their interactions exerted a significant effect on the growth of maize seedlings. Under Zn-sufficient conditions, the dry weight (DW) of shoot, root, and whole plant tended to increase in the order of NH4+ < NO3– < mixed-N nutrition. Compared with NH4+ nutrition alone, mixed-N supply resulted in a 27.4 and 28.1% increase in leaf photosynthetic rate and stomatal conductance, which further resulted in 35.7 and 33.5% of increase in shoot carbon (C) accumulation and shoot DW, respectively. Furthermore, mixed-N supply resulted in a 19.7% of higher shoot C/N ratio vs. NH4+ nutrition alone, which means a higher shoot biomass accumulation, because of a significant positive correlation between shoot C/N ratio and shoot DW (R2 = 0.682***). Additionally, mixed-N supply promoted the greatest root DW, total root length, and total root surface area and synchronously improved the root absorption capacity of N, iron, copper, manganese, magnesium, and calcium. However, the above nutrient uptake and the growth of maize seedlings supplied with NH4+ were superior to either NO3– or mixed-N nutrition under Zn-deficient conditions. These results suggested that combined applications of mixed-N nutrition and Zn fertilizer can maximize plant growth. This information may be useful for enabling integrated N management of Zn-deficient and Zn-sufficient soils and increasing plant and grain production in the future.

Sign in / Sign up

Export Citation Format

Share Document