Glasshouse experiments were conducted in winter and spring growing seasons in order to evaluate the effects of shading on production and nutritional quality of lettuce (Lactuca sativa L. cv. Parris Island), under Mediterranean climate conditions. In both seasons, plants were cultivated hydroponically under four different levels of photosynthetically active radiation intensities (26, 47, 73 and 100 % of incident light intensity). The results showed that stomatal conductance and photosynthetic rate significantly decreased in shaded plants. This strong negative correlation of leaf physiological parameters with light deficiency resulted in lower biomass yield production in both growing seasons. Moreover, the nutritional value (ascorbic acid concentration) was also significantly decreased in relation to incident light intensity decrease. In contrary, a strong positive correlation of leaf total chlorophyll content and nitrate content with light deficiency was detected. However, nitrate concentration in all treatments remained within the European Union's permissible levels being significantly lower in plants produced in spring compared to winter.

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Soil quality is a complex functional concept, which cannot be measured directly but only be inferred from both soil characteristics and cultivation practices. Among different approaches used, Soil Quality Index (SQI) is considered to be the most appropriate for quantitative assessment of soil quality. Since, there is no standard method for SQI estimation, the aim of this study is to identify soil quality parameters that could be used for the development of reliable SQI which could be effectively applied in Mediterranean ecosystems. Three different methods resulting in different SQIs were evaluated regarding their ability to monitor changes in agricultural soil properties over time. Overall, a set of soil’s parameters was used as soil health indicators (pH, CaCO3, EC, NO3-N, P, K, Mg, Cu, B, Zn, Fe, Mn, Silt, Clay, Sand and SOC) derived from 605 soil samples used to calculate the above SQIs. The most reliable SQI to distinguish the effect of the examined parameters was the weighted additive approach. These 16 soil indicators can be used as decision support tool for soil management practices, as well as indirect measures of soil function, serving to assess soil health for a sustainable Mediterranean agro-environment.

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The cultivation of cotton and in particular the quality characteristics of the fiber are mainly influenced by the growing conditions, the cultivation techniques as well as the climatic changes of the environment. The current study aimed to quantify the impact of environment, season, and their interactions on cotton fiber quality of different areas where cotton is grown in Greece. A large-scale database was created, consisting of more than 20,000 fiber samples from cotton fields of the four major cotton-producing regions of Greece (Thrace, Macedonia, Central Greece, and Thessaly) during 2016–2020, in order to evaluate thirteen fiber quality traits that were divided into four groups (fiber maturity, fiber length, color, and trash traits). The results of this work demonstrated that the effect of the environment and the interaction of the environment with year (season), were the important source of variance for almost all the qualitative characteristics studied. Regional climatic characteristics such as temperature, humidity and rainfall also significantly affected to a greater or lesser extent all quality characteristics. In conclusion, the different cultivation regions, in the broader sense of an environment that incorporates both climatic and management parameters, show stability in terms of the studied groups of quality parameters. This stability is independent of the high or low performance of the group features.