Soil and vegetation water content identify the main terrestrial ecosystem changes.

Environmental change is a consequence of many interrelated factors. How vegetation responds to natural and human activity still needs to be well established, quantified and understood. Recent satellite missions providing hydrologic and ecological indicators enable better monitoring of Earth system changes, yet there is no automatic way to address this issue directly from observations.

Experimental evidence for heritable reproductive time in 2 allochronic populations of pine processionary moth.

Phenology allows organisms to overcome seasonally variable conditions through life-cycle adjustment. Changes in phenology can drastically modify the evolutionary trajectory of a population, while a shift in the reproductive time may cause allochronic differentiation. The hypothesis of heritable reproductive time was experimentally tested, by studying a unique population of the pine processionary moth Thaumetopoea pityocampa (Den.

Why is plant-growth response to elevated CO amplified when water is limiting, but reduced when nitrogen is limiting? A growth-optimisation hypothesis.

Experimental evidence indicates that the stomatal conductance and nitrogen concentration ([N]) of foliage decline under CO enrichment, and that the percentage growth response to elevated CO is amplified under water limitation, but reduced under nitrogen limitation. We advance simple explanations for these responses based on an optimisation hypothesis applied to a simple model of the annual carbon-nitrogen-water economy of trees growing at a CO-enrichment experiment at Oak Ridge, Tennessee, USA. The model is shown to have an optimum for leaf [N], stomatal conductance and leaf area index (LAI), where annual plant productivity is maximised.

Statistical mechanics unifies different ecological patterns.

Recently there has been growing interest in the use of maximum relative entropy (MaxREnt) as a tool for statistical inference in ecology. In contrast, here we propose MaxREnt as a tool for applying statistical mechanics to ecology. We use MaxREnt to explain and predict species abundance patterns in ecological communities in terms of the most probable behaviour under given environmental constraints, in the same way that statistical mechanics explains and predicts the behaviour of thermodynamic systems.

Exogenous H(2)O(2) and catalase treatments interfere with Tri genes expression in liquid cultures of Fusarium graminearum.

Effect of exogenous H(2)O(2) and catalase was tested in liquid cultures of the deoxynivalenol and 15-acetyldeoxynivalenol-producing fungus Fusarium graminearum. Accordingly to previous results, H(2)O(2) supplementation of the culture medium leads to increased toxin production. This study indicates that this event seems to be linked to a general up regulation of genes involved in the deoxynivalenol and 15-acetyldeoxynivalenol biosynthesis pathway, commonly named Tri genes.

Accumulation of deoxynivalenol and its 15-acetylated form is significantly modulated by oxidative stress in liquid cultures of Fusarium graminearum.

Liquid cultures of Fusarium graminearum were supplemented with H2O2 or other oxidative compounds. The accumulation kinetics of the resulting trichothecenes were monitored. At non-lethal concentrations, the H2O2 treatments modulated toxin accumulation, dependent on the method of supplementation.

1H NMR and chemometrics to characterize mature grape berries in four wine-growing areas in Bordeaux, France.

The biochemical composition of grape berries depends on the cultivar genome and is influenced by environmental conditions and growing practices, which vary according to origin and "terroir" (French word accounting for the factors of climate, soil, and cultural practices on grape and wine quality). The components currently measured to determine the potential quality of grapes for wine-making at harvest are sugars, acidity, pH, and total phenolics, referred to as "classic analysis". The aim of this work was to establish metabolic profiles using both conventional physicochemical analyses and 1H NMR spectrometry of the skin and pulp of mature berry extracts in order in four appellations situated in different locations in southern-western France (Bordeaux).

Application of GFP-tagged Plum pox virus to study Prunus-PPV interactions at the whole plant and cellular levels.

The Sharka disease caused by the potyvirus Plum pox virus (PPV) is one of the most serious viral diseases affecting stone fruit trees. The study of PPV/Prunus interaction under greenhouse controlled conditions is space, time, labor consuming. While the PPV/Prunus interactions are now quite well known at the whole plant level, few data however are available on the interactions between the virus and the Prunus host plants at the cellular level.

Analogues of virus resistance genes map to QTLs for resistance to sharka disease in Prunus davidiana.

Plum pox virus (PPV), the causative agent of sharka disease in Prunoideae, is one of the most serious problems affecting stone fruit production in Europe and America. Resistance to PPV was previously described in a Prunus davidiana clone, P1908, and introduced into peach (Prunus persica) genotypes. Genetic resistance to PPV displays a complex pattern of quantitative inheritance.

Development and transferability of apricot and grape EST microsatellite markers across taxa.

EST microsatellite markers were developed in apricot (Prunus armeniaca L.) and grape (Vitis vinifera L.).

Transpiration of a 64-year-old maritime pine stand in Portugal : 1. Seasonal course of water flux through maritime pine.

The transpiration, sap flow, stomatal conductance and water relations ofPinus pinaster were determined during spring and summer in a 64-year-old stand in Ribatejo (Portugal). The transpiration of the pine canopy was determined from sap flow or eddy covariance techniques. Canopy conductance values (g ) were estimated from inversion methods using eddy covariance or sap flow data, respectively, and from scaling-up methods using stomatal conductance values measured in the field and leaf area index (LAI) values.