Vermeulen K.,Ghent University |
Aerts J.-M.,Catholic University of Leuven |
Dekock J.,Catholic University of Leuven |
Bleyaert P.,Inagro |
And 2 more authors.
Computers and Electronics in Agriculture | Year: 2012
In order to detect biotic and abiotic stress at leaf level thermal indices based on leaf temperature measurements have been commonly used. The application of these indices within glasshouse crops is, however, restricted due to the specific humid conditions and the large spatial variability of irradiance and air temperature inside a glasshouse. In this study, a novel diagnostic algorithm is proposed as an alternative method to automatically monitor the leaf temperature of a glasshouse tomato crop based on the ecophysiological interactions between a leaf and its surrounding microclimate. Given that this algorithm is intended to be implemented as a software tool in glasshouse climate control systems, a critical overview of all relevant equations found in literature was first given. Next, the most appropriate equations were selected by using two objective criteria, i.e. the commonly used R 2 and the less conventional Young Information Criterion, which also takes into account the complexity of an algorithm, so that the most feasible algorithm for automated monitoring purposes was built. Our results also showed that an in situ calibration of the selected algorithm was needed, for which a novel procedure was proposed. Once calibrated, this algorithm successfully simulated the leaf temperature of a well-watered tomato plant during several days given that the environmental conditions in its microclimate were accurately measured. Finally, the 95% confidence limits on the leaf temperature simulations provided the requested dynamic thresholds necessary for an effective automated monitoring tool. It was demonstrated that by using this novel diagnostic algorithm unexpected and likely harmful stomatal closure can be detected before visual signs of turgidity loss are observed. © 2012 Elsevier B.V.
Bleyaert P.,Inagro |
Vermeulen K.,Inagro |
Steppe K.,Ghent University |
Dekock J.,Catholic University of Leuven
Acta Horticulturae | Year: 2012
Continuous monitoring of leafy vegetables in greenhouses could be of great assistance to growers to obtain optimal plant growth with little or no basal rotting and no marginal necrosis or tipburn. However, continuous measurements of plant responses have remained mainly restricted to leaf temperature for monitoring purposes for leafy vegetables. Leaf temperature measurements can give some information about the plant transpiration rate, but direct information about the plant water status remains fairly limited, and no information at all is provided about the plant growth rate. The present contribution evaluated the use of a device which allowed online measurements of the diameter (SD) of the very short and hidden stem of butterhead lettuce (Lactuca sativa L. var. capitata). We were able to measure SD variations during the whole growing cycle in an automated way, with the exception of a short period just after transplantation. No significant sensor pressure effect on growth was observed, and the recorded SD variations showed a good correlation with manual measurements on the control plants. Moreover, we found a strong correlation between SD and plant fresh weight. However, the relationship SD versus fresh weight was season-dependent. Additionally, the sensor was able to reveal stem shrinkage due to drought stress, which means these measurements can provide instantaneous information on the actual plant water status.
Agency: Cordis | Branch: FP7 | Program: CP | Phase: ENV.2013.WATER INNO&DEMO-1 | Award Amount: 9.23M | Year: 2014
The objective of INAPRO is to mobilise industry, member states and stakeholders to promote a new and innovative technical and technological approach right up to an Aquaponic system which allows a nearly emission free sustainable production and contributes remarkably to global food security for the 21st century. Considering that traditional Aquaponic systems, combining aquaculture and hydroponics, have a great potential in saving water and energy and recovering nutrients from wastewater by value chains, the project aims at a real breakthrough for these systems towards commercialization. This will be achieved by a) the model based optimisation of the system concept in respect to water consumption and quality, environmental impact, waste avoidance, CO2 release and nutrient recycling, energy efficiency, management efforts and finally costs and b) the integration of new technologies containing cutting edge approaches such as: 1) innovative one-way water supply for horticulture and water retrieval by condensation, 2) alternative water and energy sources, 3) optimized filter systems, 4) intelligent sensor and management network for an optimized system construction and operation. The viability of INAPRO systems will be proved in concept-based demonstration projects both in rural and in urban areas that offer a potential economic advantage while simultaneously reducing water and carbon footprint. The dissemination activities (to policy, public and end-users) will open new market opportunities and improve market access inside and outside Europe for producers and technology suppliers. These ambitions meet perfectly with the EU strategies under Europe 2020 to face the challenges of dramatic water resource developments in Europe and worldwide. The project supports particularly the Innovation Union with the EIP Water as one key initiative and further the Common Agricultural Policy and will consequently be closely connected to an EIP Action Group in agricultural water management.
Agency: Cordis | Branch: FP7 | Program: CP-IP-SICA | Phase: KBBE-2009-2-5-01 | Award Amount: 7.58M | Year: 2010
VEG-i-TRADE provides platforms to identify impacts of anticipated climate change and globalisation on food safety, microbiological and chemical hazards, of fresh produce and derived food products. Control measures of managerial and technological nature will be developed in the supply chain of crop production, post-harvest processing and logistics to minimize food safety risks. The assessment of the performance of horticultural safety management systems by a novel diagnostic instrument at EU level exemplified by several countries in Europe and tailored on a global level including major EU trade partners from various climate zones will lead to recommendations on European and global level on quality assurance and the setting of science-based performance objectives. VEG-i-TRADE will pro-actively invest in problem solving technologies for safe produce investigating aspects of water quality and water treatment, horticultural production practices, disinfection treatment and packaging technologies. These control measures will be exploited in collaboration with SMEs and industrial partners. Baseline studies on the hazards, intervention technologies and best practices in the fresh produce chain will provide input for both microbial and chemical risk assessment to elaborate support to risk-based sampling plans, evaluate the risks of newly identified threats as affected by the global trade system and anticipated climate change. The project output will craft a discussion forum for stakeholders in the global food chain reflecting on issues of acceptable risk, sustainability of fresh produce production and long term strategy of international food trade, while making no compromise in food safety for European consumers and in respectation of food sovereignty. Risk communication to increase awareness of trade partners production systems and the uneven consumer behaviour will provide key conditions for prioritisation of risk management strategies.
Beck B.,Belgium Institute for Agricultural and Fisheries Research |
Brusselman E.,Belgium Institute for Agricultural and Fisheries Research |
Nuyttens D.,Belgium Institute for Agricultural and Fisheries Research |
Moens M.,Belgium Institute for Agricultural and Fisheries Research |
And 5 more authors.
Pest Management Science | Year: 2014
BACKGROUND: Steinernema carpocapsae Weiser, an entomopathogenic nematode (EPN), is a potential biological control agent for the cabbage moth (Mamestra brassicae L.). This research aimed to identify a suitable spray application technique, and to determine whether yeast extract added to an EPN spray has an attracting and/or a feeding stimulant effect on M. brassicae. The biological control capabilities of EPN against this pest were examined in the field. RESULTS: Good coverage of the underside of cauliflower leaves, the habitat of young instar larvae (L1-L4) of M. brassicae was obtained using different spray boom configurations with vertical extensions that carried underleaf spraying nozzles. One of the configurations was selected for field testing with an EPN spray. Brewer's yeast extract stimulated larval feeding on leaves, and increased the mortality of these larvae when exposed to EPN. The field trial showed that a spray application with S. carpocapsae, Addit and xanthan gum can effectively lower the numbers of cabbage heads damaged by M. brassicae. Brewer's yeast extract did not significantly increase this field performance of EPN. CONCLUSION: Steinernema carpocapsae, applied with an appropriate spray technique, can be used within biological control schemes as part of a resistance management programme for Bt.© 2013 Society of Chemical Industry.