With the dramatic increase in nanotechnologies, it has become increasingly likely that food crops will be exposed to excess engineered nanoparticles (NPs). In this study, cucumber plants were grown to full maturity in soil amended with either CeO2 or ZnO NPs at concentrations of 0, 400, and 800 mg/kg. Chlorophyll and gas exchange were monitored, and physiological markers were recorded. Results showed that, at the concentrations tested, neither CeO2 nor ZnO NPs impacted cucumber plant growth, gas exchange, and chlorophyll content. However, at 800 mg/kg treatment, CeO2 NPs reduced the yield by 31.6% compared to the control (p ≤ 0.07). ICP-MS results showed that the high concentration treatments resulted in the bioaccumulation of Ce and Zn in the fruit (1.27 mg of Ce and 110 mg Zn per kg dry weight). μ-XRF images exhibited Ce in the leaf vein vasculature, suggesting that Ce moves between tissues with water flow during transpiration. To the authors’ knowledge, this is the first holistic study focusing on the ...

Influence of CeO2 and ZnO nanoparticles on cucumber physiological markers and bioaccumulation of Ce and Zn: a life cycle study.

The standard FAO methodology for the determination of crop water requirements uses the product of reference evapotranspiration (ETo) and crop coefficient values. This methodology can be also applied to soil-grown plastic greenhouse crops, which occupy extended areas in the Mediterranean basin, but there are few data assessing methodologies for estimating ETo in plastic greenhouses. Free-drainage lysimeters were used between 1993 and 2004 to measure ETo inside a plastic greenhouse with a perennial grass in Almeria, south-eastern Spain. Mean daily measured greenhouse ETo ranged from values slightly less than 1 mm day−1 during winter to values of approximately 4 mm day−1 during summer in July. When the greenhouse surface was whitened from March to September (a common practice to control temperature), measured ETo was reduced by an average of 21.4%. Different methodologies to calculate ETo were checked against the measurements in the greenhouse without and with whitening. The methods that performed best in terms of accuracy and statistics were: FAO56 Penman–Monteith with a fixed aerodynamic resistance of 150 s m−1, FAO24 Pan Evaporation with a constant Kp of 0.79, a locally-calibrated radiation method and Hargreaves. Given the data requirements of the different methods, the Hargreaves and the radiation methods are recommended for the calculation of greenhouse ETo because of their simplicity.

https://link.springer.com/content/pdf/10.1007%2Fs00271-010-0233-5.pdf

Measurement and estimation of plastic greenhouse reference evapotranspiration in a Mediterranean climate

How does a shelter of solar panels influence water flows in a soil–crop system?

Minimal heating and cooling in a modern rose greenhouse

The sustainability of irrigated agriculture is threatening due to adverse climate change, given future projections that every one in four people on Earth might be suffering from extreme water scarcity by the year 2025. Pressurized irrigation systems and appropriate irrigation schedules can increase water productivity (i.e., product yield per unit volume of water consumed by the crop) and reduce the evaporative or system loss of water as opposed to traditional surface irrigation methods. However, in water-scarce countries, irrigation management frequently becomes a complex task. Deficit irrigation and the use of non-conventional water resources (e.g., wastewater, brackish groundwater) has been adopted in many cases as part of a climate change mitigation measures to tackle the water poverty issue. Protected cultivation systems such as greenhouses or screenhouses equipped with artificial intelligence systems present another sustainable option for improving water productivity and may help to alleviate water scarcity in these countries. This article presents a comprehensive review of the literature, which deals with sustainable irrigation for open-field and protected cultivation systems under the impact of climatic change in vulnerable areas, including the Mediterranean region.

Pilar Lorenzo

Papers

Evaluation and modelling of greenhouse cucumber-crop transpiration under high and low radiation conditions