- Farm Technology (5)
- Farm Technology Group (5)
- GTB Algemeen (5)
- WUR GTB Algemeen (5)
- GTB Tuinbouw Technologie (4)
- WUR GTB Tuinbouw Technologie (4)
- Biobased Chemistry and Technology (3)
- PE&RC (3)
- EPS (2)
- Bioint Entomology & Disease Management (1)
- GTB Gewasgez. Bodem en Water (1)
- GTB Teelt & Gewasfysiologie (1)
- Horticulture & Product Physiology (1)
- Horticulture and Product Physiology Group (1)
- Laboratory for Organic Chemistry (1)
- Laboratory of Entomology (1)
- Laboratory of Nematology (1)
- Organic Chemistry (1)
- PBR Breeding for Resistance in Solanaceae (1)
- PRI Bioint Entomology & Disease Management (1)
- WUR GTB Gewasgezondheid Bodem en Water (1)
- WUR GTB Teelt & Gewasfysiologie (1)
- WUR PB Resistance in Solanaceae (1)
- Paolo Banzato (1)
- Peter Beveren van (3)
- P. Beveren van (1)
- Peter Beveren Van (1)
- F. Bronchart (1)
- J.B. Campen (1)
- H. Che Man (3)
- Hasfalin Che Man (1)
- E. Cheret (1)
- M.L. Chiotta (1)
- S.N. Chulze (1)
- M. Combina (1)
- P. Demeyer (1)
- W. Gauchel (1)
- Somayyeh Ghasemzadeh (1)
- Wim H. Putten van der (1)
- Jack H. Vossen (1)
- J. Hemming (1)
- S. Hemming (1)
- E.J. Henten Van (1)
- Wan Ishak Wan Ismail (1)
- Gerben J. Messelink (1)
- Joop J.A. Loon van (1)
- Peter J.M. Beveren van (2)
- Abd Jamil Zakaria (1)
- F.L.K. Kempkes (1)
- Athanasios Koukounaras (1)
- J. Köhl (1)
- Jenny Lazebnik (1)
- Ada Leman (1)
- P. Linden van der (1)
- Katrin M. Meyer (1)
- Els M. Zande van de (1)
- P. Malschaert (1)
- H. Miedema (1)
- Stefania Moliterni (1)
- M.C. Nally (1)
- Nikolaos Ntagkas (1)
- Theoharis Ouzounis (1)
- M. Paepe De (1)
- Erik Pekkeriet (1)
- M.L. Ponsone (1)
- Z. Qian (1)
- Janina Radny (1)
- Kalliopi Radoglou (1)
- Ido Seginer (3)
- R. Shamshiri (3)
- Ramin Shamshiri (1)
- L.C.P.M. Smet de (1)
- Sonia Smirnakou (1)
- Gerrit Straten van (3)
- E.J.R. Sudhȍlter (1)
- G.L.A.M. Swinkels (1)
- S. Tassens (1)
- Katja Tielbörger (1)
- B.A.J. Tuijl van (1)
- R. Vis De (1)
- Ehud Wais (1)
- W.I. Wan Ismail (2)
- P.A. Weel Van (1)
- L. Wittemans (1)
- Muhammad Yamin (1)
- A.J. Zakaria (3)
Influence of seed size on performance of non-native annual plant species in a novel community at two planting densities
Radny, Janina ; Putten, Wim H. van der; Tielbörger, Katja ; Meyer, Katrin M. - \ 2018
Acta Oecologica-International Journal of Ecology (2018). - ISSN 1146-609X
Biotic interactions - Competition - Exotic species - Greenhouse - Plant size - Range expansion
Climate warming enables plant species to migrate to higher latitudes and altitudes. Within Europe, the Mediterranean harbours many species that might expand their ranges towards Western Europe. Small seed size may facilitate dispersal, however, it may impair establishment of the range-expanding plant species in the novel vegetation. In a greenhouse experiment, we examined effects of average seed size of Mediterranean plant species on their establishment in a mixed community of Western European plant species. Applying two levels of densities of the natives and a herbivory treatment, we tested how seed size is linked to response in plant growth and fitness in novel vegetation. While all non-native plant species showed a negative response to increased planting density, species with small seeds showed a less negative response. This effect persisted under herbivory. Our data suggest that small-seeded non-native plant species may tolerate competitive pressure from novel plant communities better than large-seeded species, so that small seed size may confer a higher probability of establishment of non-native species in novel communities.
Modelling the selective removal of sodium ions from greenhouse irrigation water using membrane technology
Qian, Z. ; Miedema, H. ; Smet, L.C.P.M. de; Sudhȍlter, E.J.R. - \ 2018
Chemical Engineering Research & Design 134 (2018). - ISSN 0263-8762 - p. 154 - 161.
Greenhouse - Irrigation water - Mass balance - Modelling - Na over K membrane selectivity - Sodium removal
A model is presented for the Na+ and K+ levels in the irrigation water of greenhouses, specifically those for the cultivation of tomato. The model, essentially based on mass balances, not only describes the accumulation of Na+ but includes a membrane unit for the selective removal of Na+ as well. As determined by the membrane properties, some of the K+ is removed as well. Based on real-life process parameters, the model calculates the Na+ and K+ concentration at three reference points. These process parameters include the evapotranspiration rate, the K+ uptake by the plants, the Na+ and K+ content of the fertilizer, the Na+ leaching out from the hydroponic substrate material, and the Na+ and K+ removal efficiency of the membrane unit. Using these parameters and given a constant K+ concentration of the irrigation water entering the greenhouse of 6.6 mM (resulting in the optimal K+ concentration for tomato cultivation), the composition of the solution is completely defined at all three reference points per irrigation cycle. Prime aim of this investigation is to explore the requirements for the selective membrane that currently is developed in our lab. It is found that even for a limited Na+ over K+ selectivity of 6, after a number of cycles the Na+ level reaches steady state at a level below the upper (toxic) threshold for tomato cultivation (20 mM). Economic aspects and ways of implementation of such a system are briefly discussed.
Current status and recent achievements in the field of horticulture with the use of light-emitting diodes (LEDs)
Bantis, Filippos ; Smirnakou, Sonia ; Ouzounis, Theoharis ; Koukounaras, Athanasios ; Ntagkas, Nikolaos ; Radoglou, Kalliopi - \ 2018
Scientia Horticulturae 235 (2018). - ISSN 0304-4238 - p. 437 - 451.
Greenhouse - Growth chamber - Light quality - Photomorphogenesis - Plant metabolism - Vertical farming
Light-emitting diode (LED) technology has rapidly advanced the past years and it is nowadays irrevocably linked with controlled-environment agriculture (CEA). We provide here an amalgamation of the recent research achievements in the horticulture and floriculture industry, ranging from greenhouse applications to climate rooms and vertical farming. We hope this overview bestows ample examples for researchers and growers in the selection of the appropriate LED light solution for amending crop yield, phytochemical content, nutritional value, flowering control, transplant success, pre-harvest and postharvest product quality, and production of regeneration material. We leave the reader with some future prospects and directions that need to be taken into account in this ever-growing field.
Biological control of Echinothrips americanus by phytoseiid predatory mites and the effect of pollen as supplemental food
Ghasemzadeh, Somayyeh ; Leman, Ada ; Messelink, Gerben J. - \ 2017
Experimental and Applied Acarology 73 (2017)2. - ISSN 0168-8162 - p. 209 - 221.
Amblydromalus limonicus - Amblyseius swirskii - Euseius gallicus - Euseius ovalis - Greenhouse
The poinsettia thrips, Echinothrips americanus Morgan, is an upcoming pest in greenhouse crops, causing serious damage in various vegetable and ornamental crops through extensive foliage feeding. We assessed which stages of E. americanus are attacked and killed by the phytoseiid predatory mites Amblyseius swirskii (Athias-Henriot), Amblydromalus limonicus (Garman and McGregor), Euseius gallicus Kreiter and Tixier and Euseius ovalis (Evans). Both the predation and oviposition rates were assessed in the laboratory to evaluate which mite species is potentially the most effective predator of E. americanus. In two greenhouse trials with non-flowering sweet pepper plants, we compared the efficacy of the predators E. gallicus and E. ovalis with A. swirskii and we assessed how this was affected by the application of cattail pollen. All stages of E. americanus, except adults, were consumed by all species of predatory mites. The highest predation and oviposition rates were recorded for A. limonicus followed by A. swirskii and E. ovalis when first and second larval stages were provided as prey, but E. ovalis appeared to be the best predator of thrips pupae. Euseius gallicus displayed very low predation and oviposition rates compared to the other species of predatory mites. Cattail pollen did not support the population growth of poinsettia thrips, but it strongly increased the predatory mite population densities, particularly those of E. ovalis. Both A. swirskii and E. ovalis significantly reduced thrips densities on plants. The application of pollen significantly enhanced the control of E. americanus by A. swirskii; this was not the case for E. ovalis. Euseius gallicus did not reduce densities of E. americanus on sweet pepper plants, not even at high densities in the presence of pollen.
The development of the EXE-kas
Bronchart, F. ; Demeyer, P. ; Linden, P. van der; Paepe, M. De; Vis, R. De; Wittemans, L. ; Weel, P.A. Van; Cheret, E. ; Malschaert, P. ; Tassens, S. - \ 2017
In: International Symposium on New Technologies and Management for Greenhouses - GreenSys2015 International Society for Horticultural Science (Acta Horticulturae ) - ISBN 9789462611665 - p. 453 - 460.
Dehumidification - Greenhouse - Primary energy saving - Screens - Vapour heat pump
Different primary energy saving techniques for greenhouses have been tested in the past. Those systems were designed by using the first law. However, no attention was paid to the exergy destruction in the processes (second law). This exergy destruction is related to the driving potential of the processes and the mass/energy transfer quantity, and it determines the efficiency of the system. In this paper, different energy saving techniques for greenhouses are studied based on exergy analyses at the process level. Many of the studied techniques could be labelled as "less promising". Based on this assessment, our research team select an efficient dehumidification device (vapour heat pump) and EB (Energy Balancing)-screens as most promising. A greenhouse equipped with those techniques is named "EXE-kas" (Exergy Efficient greenhouse). The prospected dehumidification efficiency of an optimal designed vapour heat pump is around 10. The use of the EB-screens results in a near neutral energy balance of the greenhouse without heating.
Day-to-night heat storage in greenhouses : 2 Sub-optimal solution for realistic weather
Seginer, Ido ; Straten, Gerrit van; Beveren, Peter J.M. van - \ 2017
Biosystems Engineering 161 (2017). - ISSN 1537-5110 - p. 188 - 199.
CO enrichment - Greenhouse - Heat buffer - Optimal control - Self-adjusting co-state
Day-to-night heat storage in water tanks (buffers) is common practice in cold-climate greenhouses, where gas is burned during the day for carbon dioxide enrichment. In Part 1 of this study, an optimal control approach was outlined for such a system, the basic idea being that the virtual value (shadow price) of the stored heat (its 'co-state') could be used to guide the instantaneous control decisions. The results for daily-periodic weather showed: (1) The optimal co-state is constant in time. (2) The optimal solution is associated with minimum time on the storage bounds (buffer empty or full). With these conclusions as guidelines, a semi-heuristic procedure of optimisation for realistic (i.e. not strictly periodic) weather is developed. The co-state remains constant while the storage trajectory is between the heat storage bounds. It is gradually increased while the buffer is empty, and decreased when the buffer is full, attempting to push the trajectory away from the bounds, thus minimising the time that the buffer is idle. The main outcomes are: (1) No information about the future is required. (2) The algorithm changes the co-state automatically, producing the correct annual variation (high in winter and low in summer). (3) The predictions of yield and heat requirement compare favourably with practice. (4) The gain in performance achievable with the suggested method is probably 75% or more of the true optimum. (5) The procedure can be used in the design stage to determine the optimal buffer size and the usefulness of other modifications of the system.
Day-to-night heat storage in greenhouses : 1 Optimisation for periodic weather
Seginer, Ido ; Straten, Gerrit van; Beveren, Peter J.M. van - \ 2017
Biosystems Engineering 161 (2017). - ISSN 1537-5110 - p. 174 - 187.
CO enrichment - Constant co-state - Greenhouse - Heat buffer - Optimal control - Periodic weather
Day-to-night heat storage using water tanks (buffers) is common practice in cold-climate greenhouses, where gas is burned during the day for carbon dioxide enrichment. In this study an optimal control approach is outlined for such a system, based on the idea that the virtual value (shadow price) of the stored heat, its 'co-state', could be used to guide the instantaneous control decisions. If this value is high, the system has an incentive to fill the heat storage (buffer), and vice versa if the co-state is low. The optimal co-state trajectory maximises the net income (performance criterion). To illustrate the method, a system description and a parameter-set roughly representative of tomato greenhouses in The Netherlands is used. The results, for daily-periodic weather, show: (1) The optimal co-state is constant (same value night and day), in contrast to the varying set-points and control fluxes. (2) The optimal solution is associated with minimum time on the storage bounds (minimum time of full or empty buffer). (3) The optimal virtual value (co-state) of stored heat is about the same as the actual cost of boiler heat during winter and about zero in summer. (4) The gain from installing a buffer is highest during spring and minimal in winter. (5) The intensive utilisation of the heat buffer in summer and its low utilisation in winter indicate that the justification of the heat storage practice, under the assumed conditions, is more the need for CO2 enrichment in summer than the need for heating in winter.
Digital growth response maps for assessment of cooling requirement in greenhouse production of tomato
Shamshiri, R. ; Che Man, H. ; Zakaria, A.J. ; Beveren, Peter van; Wan Ismail, W.I. ; Ahmad, D. - \ 2017
Acta Horticulturae 1152 (2017). - ISSN 0567-7572 - p. 117 - 124.
Computer simulation - Cooling requirement - Greenhouse - Growth response map - Temperature - Tomato - Tropical lowland
The objective of this work was to generate a series of digital growth response maps that address specific times of cooling requirement for tomato production in a tropical lowland greenhouse. Collected data from a net-screen covered greenhouse were processed by a computer model that utilized a mathematical approach to simulate tomato's growth responses (GR) to air temperature at early growth and development growth stages. Orthogonal projection was applied on three-dimensional GR plots to create top-view sketch to demonstrate variations with respect to changes in hours and days. Results indicated that air temperature inside the greenhouse was 65% optimal at the early growth stage and 72% optimal at the development growth stage of tomato.
Membership function model for defining optimality of vapor pressure deficit in closed-field cultivation of tomato
Shamshiri, R. ; Che Man, H. ; Zakaria, A.J. ; Beveren, Peter van; Wan Ismail, W.I. ; Ahmad, D. - \ 2017
Acta Horticulturae 1152 (2017). - ISSN 0567-7572 - p. 281 - 290.
Greenhouse - Growth response - Membership functions - Optimal value - Tomato - Vapor pressure deficit
Estimation of plant's evapotranspiration (ET) or water loss to the atmosphere depends on the vapor pressure deficit (VPD) of the closed-field environment (greenhouse). The objective of this work was to develop a membership function model for defining optimal VPD of greenhouse air for tomato cultivation (Lycopersicon esculentum) at different growth stages (GS) and light conditions (sun, cloud, night). Mathematical descriptions of a peer-reviewed published growth response (GR) model for optimal greenhouse air temperature (T) and relative humidity (rH) were derived and implemented in a computer program. An incremental algorithm was written in MATLAB© based on definitive concepts in VPD equations and the GR model. Nonlinear regression was applied to describe mathematical relationship between the incremented outputs of the model and the calculated VPD values (R2=0.999 to 1). Results were validated with three published literatures and were shown to be capable of exploring optimal levels of VPD by means of real numbers between 0 and 1. This study can contribute to knowledge-based information and decision support systems in greenhouse climate control and management by quantifying comfort level of microclimate.
Using a ray-tracing model to design a greenhouse with maximized transmission during winter
Swinkels, G.L.A.M. ; Kempkes, F.L.K. ; Hemming, S. - \ 2017
Acta Horticulturae 1154 (2017). - ISSN 0567-7572 - p. 179 - 183.
Greenhouse - Model - Ray tracing - Transmission - Winter
During winter, natural light limits crop growth, and it is therefore important to use all the available sunlight for crop production. Important factors that influence light transmission are the structure of the greenhouse (construction elements, orientation, roof slope, symmetrical or asymmetrical design) and the greenhouse roof material (base material, coating(s), diffuse or clear). A project was started to maximize light transmission during winter by optimizing these factors. In the first phase of the project, a simulation model was used to analyze a number of promising new concepts. To validate the simulation model, a practical experiment with scale models in the open field was carried out. During winter, the transmission of these scale models was measured. Despite a number of factors that could not be controlled or modelled, such as rain and condensation, in general there was a good match between measured and calculated values. As an overall conclusion, the simulation model showed no consistent differences from the measurements. An asymmetric cover (saw tooth) in combination with diffuse glass did not contribute significantly to light transmission in comparison with a Venlo type cover. This supported the decisions made during the design of the final full-scale demonstration greenhouse in the follow-up project.
Effects of a genetically modified potato on a non-target aphid are outweighed by cultivar differences
Lazebnik, Jenny ; Arpaia, Salvatore ; Baldacchino, Ferdinando ; Banzato, Paolo ; Moliterni, Stefania ; Vossen, Jack H. ; Zande, Els M. van de; Loon, Joop J.A. van - \ 2017
Journal of pest science 90 (2017)3. - ISSN 1612-4758 - p. 855 - 864.
Environmental risk assessment - Genetic modification - Greenhouse - Myzus persicae - Non-target testing - Phytophthora infestans - Solanum tuberosum
Insect–plant interactions may be unintentionally affected when introducing genetically modified (GM) crops into an agro-ecosystem. Our aim was to test the non-target effects of a late blight-resistant GM potato on Myzus persicae in greenhouse and climate room experiments and understand how position and number of R gene insertions can affect non-targets in GM events. We also aimed to compare results to baseline differences among three conventional potato varieties varying in resistance to late blight. Aphid development and survival were affected by some GM events in the first generation, though effects disappeared in the second generation. Effects were not dependent on the presence of a marker gene or the insertion of a second resistance gene. Positional effects of gene insertion influenced aphid performance on certain GM events. However, aphid fitness varied considerably more between conventional potato varieties than between Désirée and the GM events. Comparing different GM events to the non-transformed variety is relevant, since unintended effects of insertion can occur. Our protocols can be recommended for in planta risk assessments with aphids. Ecological perspective is gained by selecting several measured endpoints and by comparing the results with a baseline of conventional cultivars.
|Dynamic assessment of air temperature for tomato (Lycopersicon esculentum mill) cultivation in a naturally ventilated net-screen greenhouse under tropical lowlands climate
Shamshiri, R. ; Beveren, P. van; Che Man, H. ; Zakaria, A.J. - \ 2017
Journal of Agricultural Science and Technology (JAST) 19 (2017)1. - ISSN 1680-7073 - p. 59 - 72.
Greenhouse - Growth response - Natural ventilation - Optimal Temperature - Tomato
Net-screen covered greenhouses operating on natural ventilation are used as a sustainable approach for closed-field cultivation of fruits and vegetables and to eliminate insect passage and the subsequent production damage. The objective of this work was to develop a real-time assessment framework for evaluating air-temperature inside an insect-proof net-screen greenhouse in tropical lowlands of Malaysia prior to cultivation of tomato. Mathematical description of a growth response model was implemented and used in a computer application. A custom-designed data acquisition system was built for collecting 6 months of air-temperature data, during July to December 2014. For each measured air-Temperature (T), an optimality degree, denoted by Opt(T), was calculated with respect to different light conditions (sun, cloud, night) and different growth stages. Interactive three-dimensional plots were generated to demonstrate variations in Opt(T) values due to different hours and days in a growth season. Results showed that air temperature was never less than 25% optimal for early growth, and 51% for vegetative to mature fruiting stages. The average Opt(T) in the entire 6 months was between 65 and 75%. The presented framework allows tomato growers to automatically collect and process raw air temperature data and to simulate growth responses at different growth stages and light conditions. The software database can be used to track and recor Opt(T)d values from any greenhouse with different structure design, covering materials, cooling system, and growing seasons and to contribute to knowledge-based decision support systems and energy balance models.
Field test of different end-effectors for robotic harvesting of sweet-pepper
Hemming, J. ; Tuijl, B.A.J. van; Gauchel, W. ; Wais, Ehud - \ 2016
Acta Horticulturae 1130 (2016). - ISSN 0567-7572 - p. 567 - 574.
Adaptive jaws - Fin Ray effect - Grasping - Greenhouse - Gripper - Lip-type
This paper focusses on field experiments with two different types of endeffectors for robotic harvesting of sweet-pepper fruits. One of the major issues is to reach, grasp and detach the fruit efficiently, without damaging it, while avoiding obstacles in the environment. End-effectors for harvesting fruit must be able to adapt to different fruit sizes and geometries. Two types of end-effectors were designed and realized. The first one had four fingers which utilized the "Fin Ray" effect to grip the fruit. A scissor-like cut mechanism on top of the fingers was used to cut through the fruit peduncle. The second, a lip-type end-effector first stabilized the fruit using a suction cup after which two rings enclosed and cut the peduncle with a circular blade integrated in the upper lip. Both end-effectors had integrated miniature cameras with a LED illumination system: one Time of Flight camera and the other a colour camera. To study the performance of the end-effectors a number of harvesting experiments were performed in commercial sweet-pepper greenhouses. Special attention was paid to the following aspects: positioning at the target fruit, separation of the fruit from the plant, fruit damage, leaf damage and plant stem damage. Both end-effector designs had their strengths and weaknesses. The Fin ray type end-effector harvested a maximum of 80% of the fruits on the plant, the lip-type end-effector a maximum of 76% of the fruits. In none of the experiments more than 64% of the fruit could be harvested without fruit damage.
Comparative evaluation of naturally ventilated screenhouse and evaporative cooled greenhouse based on optimal vapor pressure deficit
Shamshiri, Ramin ; Ahmad, Desa ; Wan Ismail, Wan Ishak ; Man, Hasfalin Che ; Zakaria, Abd Jamil ; Beveren, Peter Van; Yamin, Muhammad - \ 2016
In: 2016 American Society of Agricultural and Biological Engineers Annual International Meeting, ASABE 2016. - American Society of Agricultural and Biological Engineers - ISBN 9781510828759 - 10 p.
Evaporative cooling - Greenhouse - Natural ventilation - Optimal - Screenhouse - Tomato - Vapor pressure deficit
The objective of this study was to compare two closed-field plant production environments for tomato cultivation based on optimal vapor pressure deficit (VPD). Experiment was carried out in tropical lowlands of Malaysia by collecting 11 days of sample data during March (2014), from an evaporative cooled Polycarbonate Panel (PP) covered greenhouse and a naturally ventilated Screenhouse (SH). A computer application was designed and used for VPD calculation and data processing with respect to three light conditions (night, sun and cloud). The average and maximum VPD were respectively equal to 0.97 and 3.81 kPa for SH and 1.19 and 5.1 kPa for PP. The largest differences in the VPD of the two environments were between 2.9 and 3.1 kPa and were observed between hours of 12:30 and 17:30 at sun conditions. Results did not show significant differences in the two environments between hours of 00:00 and 8:00, when inside air temperature was between 24 to 26°C, and relative humidity was near 90%. The hypothesis that the PP, compared to SH, provides VPD closer to the optimal range was rejected. Further analysis of the results showed that linear correlations with R2>0.9 exist between daily averaged VPD of each greenhouses. It was concluded that VPD in the SH was closer to the optimal range in the entire days of experiment. The outcome of this study contributes to knowledge-based information for greenhouse growers by addressing questions about trends in VPD data, peak-hours and light conditions associated with maximum and minimum values.
Optimal Day-to-Night Greenhouse Heat Storage : Square-Wave Weather
Seginer, Ido ; Straten, Gerrit van; Beveren, Peter van - \ 2016
IFAC-PapersOnLine 49 (2016)16. - ISSN 2405-8963 - p. 375 - 380.
Co-state - Constrained optimum - Greenhouse - Heat storage - Optimal control - Time on bounds
Day-to-night heat storage is often practiced in cold-climate greenhouses. It is suggested to manage the heat storage by considering the co-state (virtual value) of the stored heat in the on-line optimization of the greenhouse environment. Examples worked out for a periodic square-wave weather show that a properly selected constant co-state can produce an optimal solution to the control problem. The optimal co-state is shown to change with time over the year. Maximizing the performance criterion can also be achieved by minimizing the time that the heat buffer is either completely empty or completely full.
Evaluation of the effectiveness of potential biocontrol yeasts against black sur rot and ochratoxin A occurring under greenhouse and field grape production conditions
Ponsone, M.L. ; Nally, M.C. ; Chiotta, M.L. ; Combina, M. ; Köhl, J. ; Chulze, S.N. - \ 2016
Biological Control 103 (2016). - ISSN 1049-9644 - p. 78 - 85.
Aspergillus carbonarius - Biocontrol - Field - Grapes - Greenhouse - Ochratoxin A
The efficacy of two strains of Lanchancea thermotolerans in preventing the growth and ochratoxin A (OTA) accumulation of ochratoxigenic fungi under greenhouse and field conditions were evaluated during three consecutive year trials. The data from this study showed that both yeast strains were able to control Aspergillus section Nigri species ochratoxin A accumulation in wine grapes at harvest stage. The inhibitory effects were dependent on the ochratoxigenic species, yeast strains, and year analyzed. Over all conditions assayed, ochratoxin A accumulation was reduced from 27% to 100%, depending on the conditions evaluated. These results are promising for future development of a bio-pesticide.
Contribution of innovative technologies to new developments in horticulture
Pekkeriet, Erik ; Henten, E.J. Van; Campen, J.B. - \ 2015
In: Acta Horticulturae International Society for Horticultural Science (Acta Horticulturae ) - ISBN 9789462610965 - p. 45 - 54.
Automation - Dehumidification - Energy solutions - Greenhouse - Greenhouse cover materials - Mechanization - Robotics - Sensors
This paper reviews new developments in high-tech greenhouse horticulture. It will focus on sensors, energy solutions, covering materials, production technology and robotics. Driving forces for new technologies are identified and Dutch greenhouse crop production is used as an example. Sensors are introduced in horticulture using the latest techniques from medical and industrial research. A 3D volumetric intersection technique is used to sort tomato seedlings at a speed of 40.000 pieces per hour and measures the full 3D geometric features, which is clearly an impossible challenge when done manually. Other 3D techniques like stereo vision, time of flight and laser triangulation are introduced in greenhouse horticulture to control robots, measure the geometric quality features as flower diameter and bulb orientation or to separate target features from its agricultural surroundings (e.g., Anthurium, chicory, lily bulbs). But also the interest to measure internal quality features as ripeness, food compounds, internal defects and the ability of photosynthesis capacity can be measured by spectral cameras, fluorescence techniques and X-ray. First applications in research and production are being introduced (e.g., rose, Alstroemeria, tulip, tomato or cucumber). To apply integrated management on pests and diseases in the greenhouse, sensors are needed to determine pests and diseases and its magnitude automatically at an early stage (e.g., long horn beetle, botrytis, sticky plates). More future sensor applications are expected in this field. New developments in energy solutions in greenhouses will lead to more profitable options in crop production. Energy saving in horticulture has been the subject of research for more than 20 years in a special program "greenhouse as energy source" financed by the Dutch ministry of agriculture and growers. The result is that Horticultural industry in The Netherlands consumes now 50% less energy compared to 1990 due to all energy saving measures. Various technologies developed are now common practice in greenhouses like the application of thermal screens and temperature integration. More recent developments in humidity control have been adopted further decreasing energy consumption and thereby even increasing production quality and quantity. Alternative energy sources like geothermal heat are being used by some growers allowing fossil-fuel free vegetable production. More futuristic concepts where electricity and heat are produced in combination with greenhouse production are still in the experimental phase. When all new developments lead to products with excellent quality in the right amount, price and ready just in time, products need to be harvested with a predictable capacity and reliability. Progress is made on robotic harvesting of fruits, flowers and vegetables. First robots that are tested in practice on a 24/7 base (cutrose, strawberry, kiwi) have shown to be very close to market introduction. Progress is made and big efforts by several consortia are put in actual developments to harvest tomato leaves, cucumbers and sweet peppers. Self-learning algorithms, open source robotic software and generic mechatronic solutions are available and adaptive to new tasks and products and will enable fast future robot solutions after first successful introductions.