Irrigation of Mediterranean crops with saline water: from physiology to management practices

Summarization: Salinity is currently one of the most severe abiotic factors limiting agricultural production. The high rates of population growth and global warming are expected to further exacerbate the threat of salinity, especially in areas with a semi-arid climate as in the Mediterranean region. Salinity affects plant performance through the development of osmotic stress and disruption of ion homeostasis, which in turn cause metabolic dysfunctions. Particular emphasis is given on the impacts of salinity on photosynthesis because of its potential restrictions on plant growth and yield. The inhibition of photosynthesis under low to moderate salinity stress appear to be mainly attributed to diffusional limitations (stomatal and mesophyll conductance), even for salt-sensitive fruit trees such as citrus trees. In contrast, biochemical limitations to photosynthesis appear to occur only when stress becomes heavy. A thorough understanding of the mechanisms conferring salt tolerance is therefore essential under the expected climatic change, as it will enable the selection of salt-tolerant genotypes and the adoption of appropriate practices to alleviate salinity impacts on agricultural production. In fruit trees, salt tolerance is mainly associated with their ability to restrict salt accumulation in the leaves. Cell features of specific tissues, morphological factors and water-use efficiency regulate salt accumulation in the shoot. Furthermore, most fruit trees display a rapid osmotic adjustment in response to salinity, which is mainly attributed to the accumulation of inorganic ions and carbohydrates. Little information is available about the ability of horticultural crops to detoxify reactive oxygen species and to synthesize compatible solutes and hence on the potential contribution of these mechanism to induce salt tolerance in horticultural crops.Presented on: Agriculture, Ecosystems and Environmen

Irrigation with saline water in the Mediterranean Region and its consequences on photosynthesis of fruits and vegetables

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: Photosynthesis in a Changing Worl

Genotypic responses of Soultanina grapevines in water relations and gas exchange under different irrigation regimes and water qualities

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: 13th Congress of FESP

Growth and gas exchange of Soultanina vines as affected by irrigation level, water quality and rootstock

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: 6th International Symposium on Grapevine Physiology and Biotechnolog

Grapevine growth and nutrition as affected by irrigation with secondary treated effluent

Μη διαθέσιμη περίληψηNot available summarizationΠαρουσιάστηκε στο: Regional Symposium on Water Recycling in Mediterranean Regio

Alternative technologies for olive mill wastewater management with emphasis on soil application

Summarization: The disposal of olive mill wastewater (OMW) produced during oil extraction in Mediterranean countries creates a significant environmental problem because of the great volumes of effluent produced (10-12 Mm3 year-1), heavy pollution load (40-80 g L-1 biological oxygen demand (BOD), 50-150 g L-1 chemical oxygen demand (COD)) and phytotoxic properties (because of phenolic compounds). During the last 30 years, many OMW treatment methods have been proposed and tested, but their application at the olive mill level is limited because of the high investment and/or running costs and technical expertise required. Existing technologies for OMW management have been identified and evaluated with the LIFE+ OLEICO+ project following certain criteria that are currently being used in Portugal, Spain, Italy and Greece. The results show that several viable technologies for OMW treatment do exist (composting, electro-coagulation, hydrolysis-oxidation, phyto-remediation, co-digestion, energy production); however, they require capital investment and maintenance costs that cannot be afforded by a small or medium olive mill plants. On the other hand, application of OMW to olive orchards can be a low-cost alternative method for OMW treatment in regions with small olive oil mill enterprises. Annual rates up to 1500 L tree-1 were applied in five equal doses, at 20-day intervals between November and February. Soil analyses were performed before the onset and after the end of the OMW application period. The response of olive trees to OMW application was monitored by measuring plant nutritional status, photosynthesis and yield. Furthermore, the possibility of groundwater pollution by the application of fresh OMW was investigated with lysimeters. OMW-treated soil had higher K content throughout the experiment. Phenols were decomposed rapidly, and therefore the phenolic content before the onset of a new OMW application period was negligible. The nutritional status, physiology and yield of olive trees were not affected by the application of OMW. The total olive orchard area required for the annual OMW production was 3.6 ha (280 trees ha-1), which is easily available around an olive mill. The cost of application is €0.007 L-1 OMW, which seems reasonable compared with more sophisticated methods. Detailed study for each case is required in order to determine the application dose according to soil and climatic conditions of the area. The results show that several viable technologies do exist; however, the implementation cost is not negligible.Παρουσιάστηκε στο: Acta Horticultura