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Leaf P Concentration (leaf + p_concentration)

Distribution by Scientific Domains

Life Sciences	100%

Distribution within Life Sciences

Plant Science	57%
Ecology & Organismal Biology	28%

Selected Abstracts

A global study of relationships between leaf traits, climate and soil measures of nutrient fertility

GLOBAL ECOLOGY, Issue 2 2009
Jenny C. Ordoñez
ABSTRACT Aim This first global quantification of the relationship between leaf traits and soil nutrient fertility reflects the trade-off between growth and nutrient conservation. The power of soils versus climate in predicting leaf trait values is assessed in bivariate and multivariate analyses and is compared with the distribution of growth forms (as a discrete classification of vegetation) across gradients of soil fertility and climate. Location All continents except for Antarctica. Methods Data on specific leaf area (SLA), leaf N concentration (LNC), leaf P concentration (LPC) and leaf N:P were collected for 474 species distributed across 99 sites (809 records), together with abiotic information from each study site. Individual and combined effects of soils and climate on leaf traits were quantified using maximum likelihood methods. Differences in occurrence of growth form across soil fertility and climate were determined by one-way ANOVA. Results There was a consistent increase in SLA, LNC and LPC with increasing soil fertility. SLA was related to proxies of N supply, LNC to both soil total N and P and LPC was only related to proxies of P supply. Soil nutrient measures explained more variance in leaf traits among sites than climate in bivariate analysis. Multivariate analysis showed that climate interacted with soil nutrients for SLA and area-based LNC. Mass-based LNC and LPC were determined mostly by soil fertility, but soil P was highly correlated to precipitation. Relationships of leaf traits to soil nutrients were stronger than those of growth form versus soil nutrients. In contrast, climate determined distribution of growth form more strongly than it did leaf traits. Main conclusions We provide the first global quantification of the trade-off between traits associated with growth and resource conservation ,strategies' in relation to soil fertility. Precipitation but not temperature affected this trade-off. Continuous leaf traits might be better predictors of plant responses to nutrient supply than growth form, but growth forms reflect important aspects of plant species distribution with climate. [source]

Mycorrhizal infection and high soil phosphorus improve vegetative growth and the female and male functions in tomato

NEW PHYTOLOGIST, Issue 1 2002
Jennifer L. Poulton
Summary ,,To further characterize the effects of mycorrhizal infection and soil phosphorus (P) availability on plant fitness, this study examined their effects on the female and male functions, as well as vegetative growth of tomato (Lycopersicon esculentum). ,,Two cultivars of tomato were grown in a glasshouse under three treatment combinations: nonmycorrhizal, low P (NMPO); nonmycorrhizal, high P (NMP3); and mycorrhizal, low P (MPO). ,,Mycorrhizal infection and high soil P conditions improved several vegetative (leaf area, days until first flower and leaf P concentration) and reproductive traits (total flower production, fruit mass, seed number and pollen production per plant, and mean pollen production per flower). In general, mycorrhizal and P responses were greater for reproductive traits than vegetative traits. In one cultivar, these responses were greater for the male function than the female function. ,,Thus, mycorrhizal infection and high soil P conditions enhanced fitness through both the female and male functions. Similar trends were usually observed in the NMP3 and MPO treatments, suggesting that mycorrhizal effects were largely the result of improved P acquisition. [source]

Physiological changes in white lupin associated with variation in root-zone CO2 concentration and cluster-root P mobilization

PLANT CELL & ENVIRONMENT, Issue 10 2005
M. D. CRAMER
ABSTRACT White lupin (Lupinus albus L.) mobilizes insoluble soil phosphorus through exudation of organic acids from ,cluster' roots. Organic acid synthesis requires anaplerotic carbon derived from dark CO2 fixation involving PEP-carboxylase. We tested the hypothesis that variation in root-zone CO2 concentration would influence organic acid synthesis and thus P mobilization. Root-zone CO2 concentrations and soil FePO4 concentrations supplied to sand-grown white lupin (cv. Kiev Mutant) were varied. More biomass accumulated in plants supplied with 360 µL L,1 CO2 to the root-zone, compared with those aerated with either 100 or 6000 µL L,1 CO2. Increased FePO4 in the sand resulted in greater leaf P concentrations, but root-zone [CO2] did not influence leaf P concentration. Suppression of cluster-root development in plants supplied with 100 µL L,1 root-zone CO2 was correlated with increased leaf [P]. However, at both 360 and 6000 µL L,1 CO2, cluster-root development was suppressed only at the highest leaf P concentration. Phloem sap [P] was significantly increased by greater [FePO4] in the sand, but was reduced with increased root-zone [CO2], and this may have triggered increased cluster-root initiation. Succinate was the major organic acid (carboxylate) in the phloem sap (minor components included malate, citrate, fumarate) and was increased at greater [FePO4], suggesting that this shoot-derived carboxylate might provide an important source of organic acids for root metabolism. Since cluster root development was inhibited by increasing concentrations of FePO4 in the sand, it is possible that succinate was utilized for the functioning of the root-nodules. [source]

Shifts in leaf N : P ratio during resorption reflect soil P in temperate rainforest

FUNCTIONAL ECOLOGY, Issue 4 2008
Sarah J. Richardson
Summary 1Large-scale syntheses of leaf and litter N and P concentrations have demonstrated that leaf and litter N : P ratios both decline with latitude, that litter N : P ratios are generally greater than those of fresh leaves, and that the difference between these two ratios increases towards the tropics. These patterns have been ascribed to either a direct effect of temperature on plant growth rates and leaf-level physiology, or a decline in soil P towards the tropics. We test the hypothesis that global patterns of leaf and litter N : P ratios reflect a soil-P gradient by examining leaf and litter N : P in all species from a temperate rainforest along a soil-P gradient. 2The soil P gradient followed a toposequence of 20 plots. There was > 50-fold variation in soil total P from ridges (23,136 mg kg,1), through faces and terraces (32,744 mg kg,1), to gullies (440,1214 mg kg,1). 3The N : P ratios of leaves and litter both declined as soil total P increased, and the N : P ratio of litter was greater than that of fresh leaves. The difference between litter N : P and fresh leaf N : P declined with increasing soil total P supporting the hypothesis that global patterns of N : P ratios reflect gradients of soil P. 4Compositional turnover with soil P partly contributed to the total plant community leaf and litter nutrient concentration responses. However, consistent within-species responses pointed to a soil-based mechanism for determining responses by the total plant community. 5Comparisons of our litter data to global data sets suggest that the vegetation was well adapted to low soil nutrient concentrations with 37% of litter N and 24% of litter P samples being below published thresholds for highly proficient nutrient resorption. 6The range of leaf N and leaf P concentrations at our site captured a large portion of the range reported in global leaf trait data sets. 7Highly proficient P resorption was responsible for the divergence in leaf and litter N : P ratios on P-poor soils. These results emphasize the significance of proficient nutrient resorption as an advantageous plant trait for nutrient conservation on P-poor soils. [source]

Physiological changes in white lupin associated with variation in root-zone CO2 concentration and cluster-root P mobilization

Restoration of a Mediterranean Postfire Shrubland: Plant Functional Responses to Organic Soil Amendment

RESTORATION ECOLOGY, Issue 5 2010
Marie Larchevêque
We investigated the potential of plant functional responses to speed up restoration in a postfire ecosystem. The patterns of change in plant nutrient uptake and water potential after compost amendment were monitored for 2 years in a 7-year-old postfire shrubland in southeastern France. We studied four different stress-tolerant species with contrasting life traits: three shrub species and a perennial herb. Three treatments were applied: control, 50 and 100 Mg/ha of fresh cocomposted sewage sludge and green waste. In both compost treatments, concentrations of all the macronutrients increased. The amendment improved N and cation nutrition, but the positive effect of compost on plant nutrient status was most apparent on leaf P concentrations, indicating that P was a limiting nutrient in this shrubland. Compost had no significant short-term effect on trace metal concentrations in plants. The plant nutrition response of different species to the compost varied; the nutritional status of Brachypodium retusum and Cistus albidus improved the most, whereas that of Quercus coccifera and Ulex parviflorus improved the least. Woody species exhibited no increase in N stocks. Phosphorus accumulation was also about three times higher in plots amended at 50 Mg/ha than in control plots for B. retusum and C. albidus. The severe summer drought of 2003 altered the compost effect. Contrary to our expectations, plants on amended plots did not exhibit a better water status in summer: the effect of the summer drought had a greater effect on water status than did the compost treatment. [source]