Estimativa da área foliar do pepino em ambiente protegido por medidas lineares sob salinidade e enxertia

The measurement of leaf area by linear parameters is a useful tool when plants cannot be destroyed for direct measurement. The objectives of this study were to establish equations to estimate the leaf area of greenhouse-cucumber and to evaluate the effects of salinity and grafting on this estimative. Non-grafted cucumber seedlings, cv. 'Hokushin', were transplanted in a greenhouse and were irrigated with water of different salinities (1.0, 3.2 and 5.0 dS m-1). In the second growing period, the same cultivar was grafted on Cucurbita spp. and the plants were irrigated with water of 1.4, 3.0 and 5.3 dS m-1. Leaves of different sizes were collected from both experiments and leaf area was determined by an integrating area meter. Leaf length (L) and width (W) were also recorded. An equation for estimating the leaf area from L and W was developed for a given salinity level or grafting condition and estimated well the area of leaves collected in the other treatments. The leaf area (LA) of cucumber 'Hokushin' could be estimated using the equation LA = 0.88LW - 4.27, for any grafting and salinity conditions.A determinação da área foliar por medidas lineares é uma ferramenta útil quando as plantas não podem ser destruídas para que a medição direta seja realizada. Os objetivos desse trabalho foram definir equações para a estimativa da área foliar do pepino em ambiente protegido e avaliar os efeitos da salinidade e da a enxertia nessa estimativa. Mudas de pepino, cv. 'Hokushin', não enxertadas, foram transplantadas em um ambiente protegido e irrigadas com água de diferentes salinidades (1,0, 3,2 e 5,0 dS m-1). No segundo período de cultivo, a mesma cultivar foi enxertada sobre Cucurbita spp., sendo as plantas irrigadas com água de 1,4, 3,0 e 5,3 dS m-1. Foram coletadas folhas de diferentes tamanhos dos dois cultivos e dos três tratamentos e a área foliar foi determinada por um medidor de área foliar. O comprimento (C) e a largura (L) da folha também foram registrados. Desenvolveram-se equações pelas quais a área foliar pôde ser estimada a partir de medidas de C e L. A equação desenvolvida para um dado nível de salinidade ou condição de enxertia estimou bem a área das folhas coletadas nos demais tratamentos. A área foliar (AF) do pepino 'Hokushin' pode ser estimada pela função AF = 0,88CL - 4,27, para qualquer condição de enxertia e salinidade

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