The effect of water stress and rootstock on the development of leaf injuries in grapevines irrigated with saline effluent

Deficit irrigation is increasingly being practiced in water-limited areas to overcome water scarcities. Although, this practice reduces yield losses, there is limited information currently available on how this practice can affect crops when the irrigation water contains elevated levels of salts. An experiment was set up to investigate salt uptake and distribution and salt tolerance of potted Soultanina vines grafted on different rootstocks (41B, 1103P, 110R) and irrigated with effluent containing relatively high concentrations of salts and fresh water at different fractions of evapotranspiration (0.50, 0.75 and 1.00ET). Irrigation with recycled water induced the development of leaf burns, which were more intense in 1998 despite the lower leaf-Na and -Cl content. This may have been due to the more severe water deficit and/or to the more adverse climatic conditions which prevailed during that season. Decreasing the irrigation level induced the development of leaf burns causing only minor changes to leaf-Na or -Cl content. Differences in salt uptake, accumulation and distribution were observed among the rootstocks investigated in this work, suggesting that differences exist in the mechanisms regulating salt uptake and distribution in the shoot. Despite these differences, a distinct superiority in terms of salinity tolerance among rootstocks was only observed at the 0.50ET irrigation level, where vines grafted on 41B developed earlier and more acute leaf burns than the other rootstocks. These findings suggest that leaf salt content alone it is not to classify genotypes according to their tolerance to salinity and that salinity-induced damage is linked with prevailing environmental conditions. Furthermore, it can be inferred that grapevines have additional mechanisms to cope with salt stress which may counteract differences in salt uptake and accumulation in the shoot.

Water reuse in EU states: Necessity for uniform criteria to mitigate human and environmental risks

10.1080/10643389.2014.955629Critical Reviews in Environmental Science and Technology45131409-146

Modeling the impact of carbon amendments on soil ecosystem functions using the 1D-ICZ model

In the next four decades, humanity needs to double food and energy production and increase the supply of clean water by over 50% while mitigating and adapting to climate change. A central element in the strategy of addressing these major environmental challenges is to maintain the central role of Earth's essential soil functions and related ecosystem services. Many soil functions are affected by soil structure in terms of particle aggregation and porosity. The objective of this work is to model soil structure and biomass dynamics, nutrients uptake, and yields using the 1D Integrated Critical Zone (1D-ICZ) model which is a mechanistic mathematical description of soil processes and functions. The 1D-ICZ model simulates the coupled processes that underpin major soil functions including water flow and storage, biomass production, carbon and nutrient sequestration, pollutant transformation, and supporting biological processes, and thus is capable of quantifying essential soil ecosystem services. The model was validated using data derived from a field experiment where tomato plants were grown using different treatments of commercial mineral fertilizers, compost, manure, and a 30% manure–70% compost amendment. Detailed data have been collected over four growing seasons on soil and soil solution chemistry, aggregate formation, and plant production. The model has been able to capture the biomass production, the temporal dynamics of the water-stable aggregate formation and the dynamics of carbon and nutrient sequestration in the different sizes aggregates as well as the variability of water filtration and transformation efficiency in the different amendment treatments. The model results demonstrate the value of applying computational simulation tools such as the 1D-ICZ model to test options for improved land management measures and to support sustainable land care practices

Integrated critical zone model (1D-ICZ): a tool for dynamic simulation of soil functions and soil structure

Food security should be addressed in relation to soil sustainability and sustainable land care, and examined within the science framework of Earth's critical zone as an integrated system that includes Earth surface interactions, connected to soil functions, and ecosystem services. There is a great need to develop critical zone mathematical models that will simulate and quantify soil functions and that can be used as management tools to address soil sustainability and land care practices. The integrated critical zone model, 1D-ICZ, couples computational modules for soil organic matter dynamics, soil aggregation and structure dynamics, bioturbation, plant productivity and nutrient uptake, water flow, solute speciation and transport, and mineral weathering kinetics. The 1D-ICZ model, coupled with new pedotransfer functions to predict bulk soil properties, introduces for the first time a model that dynamically links soil structure characteristics and hydraulic soil properties by simulating their changes under varying meteorological conditions and plant growth. Field data from a Mediterranean olive grove at the Koiliaris Critical Zone Observatory (CZO) were used to simulate carbon addition to soil and agricultural management scenarios, in order to illustrate the model's ability to quantify soil management impact on soil functions and biogeochemical transformations and fluxes. The 1D-ICZ model can be used to assess, understand, and quantify the complex interactions between the different processes in the soil-plant-water system and can be applied as a tool to design sustainable agricultural management practices, taking into consideration synergy and trade-offs among soil functions

Physiological and molecular responses of grapevine to salinity/drought

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: Congress on Aquaporin

Influência de porta-enxertos na resistência de mudas de cajueiro ao estresse salino Influence of rootstocks on the resistance of cashew plantlets to salt stress

O objetivo deste trabalho foi avaliar a influência de porta-enxertos na resistência de mudas de cajueiro (Anacardium occidentale L.) à salinidade. As mudas foram obtidas pela enxertia do clone BRS 226 sobre os porta-enxertos CAPI 4, CCP 09 e BRS 226. Foram expostas a meio hidropônico sem NaCl (controle) ou com NaCl 200 mM (tratamento salino), sob condições controladas de temperatura, umidade e luminosidade, durante 12 dias. O delineamento foi o inteiramente casualizado, em esquema fatorial 3x2 (três combinações de enxerto/porta-enxerto e duas concentrações de NaCl), com quatro repetições. Foram determinados a concentração de Na+, Cl-, K+ e solutos orgânicos e os sintomas visuais de toxicidade nas folhas. Os conteúdos de Na+ e Cl-, a relação K+/Na+ e as concentrações de aminoácidos e de prolina livres nas folhas tiveram relação direta com os sintomas visuais de toxicidade. Os porta-enxertos CAPI 4, CCP 09 e BRS 226 foram classificados como sensível, intermediário e resistente à salinidade elevada, respectivamente. Essa variação foi decorrente da influência do porta-enxerto na partição do Na+ e do Cl-.<br>The aim of this work was to evaluate the influence of cashew (Anacardium occidentale L.) rootstocks on salt resistance in grafted plantlets. The plantlets were obtained by grafting the BRS 226 scion on CAPI 4, CCP 09 and BRS 226 rootstocks, and were exposed to nutrient solution without NaCl (control) or with 200 mM NaCl (salt treatment) in hydroponics under controlled temperature, humidity, and luminosity conditions during 12 days. The experimental design was a completely randomized in factorial arrangement 3x2 (three scion/rootstock combinations, two NaCl concentrations) with four replicates. Na+, Cl-, K+ and organic solute concentrations and toxicity symptoms on leaves were determined. Na+ and Cl- contents, the K+/Na+ ratio and the free amino acid and proline concentrations in leaves were directly related to the visual toxicity symptoms. The rootstocks were classified as sensitive (CAPI 4), intermediate (CCP 09), and resistant (BRS 226) to high salinity. This variation was a consequence of the rootstock influence on Na+ and Cl- partitioning