Projects from Horticulture and Product Physiology
Search for    
Low temperature and low light intensity storage to increase shelf life of butterhead lettuce
We have found before that quality deterioration of lettuce during postharvest storage is delayed by low temperature in combination with very low light levels (about 5 µmol m2s1). This is likely caused by ongoing photosynthesis and greatly reduced respiration rates. Think of using of LED lighting in  ...
Supervisor: Dr. Rob Schouten, Dr. Elias Kaiser, Prof. Ernst Woltering
Using seedlings to predict photosynthetic induction in mature plants?
Plants in nature or greenhouses are often exposed to rapidly changing light intensities, which has major impacts on these plants’ photosynthesis rate. The rapidity with which a plant can respond to a change in light intensity is often measured using photosynthetic induction: a plant initially expose ...
Supervisor: Dr. Elias Kaiser
Investigating light spectrum effects of LED inter-canopy lighting in greenhouse cucumber
Vine crops, specifically tomatoes and cucumbers, represent one of the largest segments for electric lighting in horticultural applications. Furthermore, cultivators are constrained by inadequate lighting conditions during winter months and high operating costs for traditional lighting systems. LED l ...
Supervisor: ir. Tijmen Kerstens, Dr. Ep Heuvelink
Does a diel cycle shorter than 24h or continuous light positively affect lettuce growth and light use efficiency; is this response genotype dependent?
Vertical Farming is a new model in food production with high water, fertilizer and land use efficiency compared to traditional cultivation. No pesticides are applied and since this novel system allows worldwide cultivation, it reduces food mileage promoting local production (even within urban areas! ...
Supervisor: Diego Nunez, Ep Heuvelink
Measuring the diurnal rhythms of photosynthesis
Like most organisms, plants have an internal clock that regulates processes on a 24 hour schedule. This includes processes connected to photosynthesis, such as diurnal CO2 uptake, stomatal conductance, chlorophyll fluorescence, protein turnover, and many more. When a plant that has been growing unde ...
Supervisor: Dr. Elias Kaiser, Dr. Silvere Vialet-Chabrand
The light response of photosynthetic induction
Plants in nature or greenhouses are often exposed to rapidly changing light intensities, which has major impacts on these plants’ photosynthesis rate. The rapidity with which a plant can respond to a change in light intensity is often measured using photosynthetic induction: a plant initially expose ...
Supervisor: Dr. Ningyi Zhang, Dr. Elias Kaiser
Vertical farming versus conventional farming: A comparative study
Vertical farming is an emerging practice consisting in cultivating crops under full LED conditions on vertically stacked layers which provides numerous advantages compared to conventional farming (i.e. greenhouses). Firstly, vertical farms can be implemented in existing empty buildings or warehouses ...
Supervisor: Dr. Sarah Courbier (daily supervisor) and Prof. dr. Leo F. M. Marcelis
Influence of mitochondrial respiration on diurnal stomatal behaviour
Photosynthesis, the primary determinant of plant biomass depends on light intensity and CO2 availability at the sites of carboxylation. Stomatal conductance (gs), a measure of the ease at which gas diffuses through stomata over the leaf surface is closely correlated with the rate of carbon assimilat ...
Supervisor: Dr. Silvere Vialet-Chabrand
About time: How light influences anthocyanin biosynthesis and stability in lettuce
Global food demand is increasing due to the growing human population and pushes breeding towards highly productive cultivars. As production increases, the nutritional quality (minerals and phytochemicals) of these crops usually decreases. However, minerals and phytochemicals contained in food are es ...
Supervisor: Dr. Sarah Courbier (daily supervisor) and Prof. dr. Leo F. M. Marcelis
Desk study: Meta-analysis of photosynthesis dynamics – would you like to crunch data?
In nature, leaves are often exposed to fluctuations in light intensities, causing photosynthesis to respond at various time scales. While we are only starting to realize how important these fluctuations are for plant productivity, most photosynthesis research is still done under conditions in which  ...
Supervisor: Dr. Elias Kaiser
Photosynthetic induction at high [CO2]: quantifying the “dip”
Irradiance frequently fluctuates under natural conditions and in greenhouses. When light intensity suddenly increases, leaf photosynthesis progressively increases rather than instantaneously increasing to the steady-state level (a process termed photosynthetic induction). The main limiting processes ...
Supervisor: Dr. Ningyi Zhang, Dr. Elias Kaiser
Does light spectrum influence fruit set in sweet pepper?
Fruit set indicates the initiation of fruit growth derived from flowers, and the cessation of this process is termed as abortion. Fruit set is a crucial development process in the plant life cycle, and it is also a main determinant of crop yield. In sweet pepper, up to 80% of all flowers can abort.  ...
Supervisor: Sijia Chen (PhD candidate) and Dr. Ep Heuvelink
Diural gas exchange: Interaction between foliar and non-foliar tissues
Fruit growth results from the balance between influx of water, nutrients and assimilates and losses due to fruit transpiration and respiration (Windt et al., 2009). Water influx in the fruits occurs in part through the xylem in competition with the rest of the plant, and for that reason fruit growth ...
Supervisor: Dr. Silvere Vialet-Chabrand, Dr. Rob Schouten
Leaf boundary layer conductance: the final frontier for diffusion
Leaf-boundary-layer conductance (gb) represents the ease of diffusion through the air layer formed along the leaf surface due to reduced velocity and is mainly influenced by air speed. Under low air speed (e.g. within a plant canopy), gb is an important limiting factor on energy budgets, transpirati ...
Supervisor: Dr. Silvere Vialet-Chabrand
Desk study: Is the use of interlighting in greenhouse production beneficial or wasteful?
In modern greenhouse production, plants are often grown in relatively tall, optically dense canopies –think of tomato, cucumber and bell pepper. Often, supplementary lighting installed above the plants (toplighting) is used to stimulate growth. The introduction of LEDs, which emit much less heat tha ...
Supervisor: Dr. Elias Kaiser
Developing a functional structural plant model of Artemisia annua
Artemisia annua is an important medicinal species. Its secondary metabolite, artemisinin, has been used in the treatment of malaria, as well as several cancers and viral diseases. In many developing and underdeveloped regions, artemisia plants are growing by local farmers. In most cases, plant growt ...
Supervisor: Dr. Ningyi Zhang, Prof. dr. Leo F.M. Marcelis
Can a low-cost chlorophyll fluorescence imager be used to monitor plant performance?
Monitoring plant performance in the greenhouse is essential to achieve an optimal and automatic control of the climate that can respond to changes in plant performance. In research studies, leaf chlorophyll fluorescence is often monitored in greenhouses, as it provides a proxy for photosynthesis and ...
Supervisor: Dr. Silvere Vialet-Chabrand, Dr. Elias Kaiser
Internships at Ter Laak Orchids (location: Wateringen)
Ter Laak Orchids is one of the leading nurseries of Phaleanopsis potplant in Europe. We are located in Wateringen, in the west of Holland in the Westland area. With our 140 employees, we grow yearly more than 6 million Phalaenopsis plants. We have 125,000 m2 production area spread over two modern, s ...
Supervisor: External supervisor: Ewald de Koning (Ter Laak Orchids)
Contact HPP: Dr. Ep Heuvelink
Internship: Monitoring growth and development of a variety of chrysanthemum cultivars during different seasons
The AGROS project “Towards an autonomous greenhouse”, works on the realization of the 'autonomous greenhouse' in which cultivation is controlled remotely via intelligent algorithms, based on measurements of crop properties with the help of intelligent sensors and advanced crop growth models. Model c ...
Supervisor: Wageningen UR Greenhouse Horticulture/Dekker Chrysanthemum: Dr. Anne Elings (
HPP supervisor: to be determined
Internships: Viscon Group/ViVi, Varied topics on plant cultivation in a controlled environment
The Viscon Group is passionate about creating innovative, solid and smart logistic solutions for all handling processes in Food and Agro businesses. The Viscon DNA consists of asking many questions, learning every day and developing new business in new sectors and markets: constantly generating idea ...
Supervisor: External supervisor(s): Su Zhang, Damian Lopez, Femke Gouweleeuw
Contact HPP: Ep Heuvelink
Internship in vertical farming at INFARM (Berlin, Germany)
Possible topics: 1. How low can we go? Understanding light harvesting abilities of herbs and leafy greens. In order to optimize light use for photosynthesis in vertical farming we would like to explore the maximum light use of various herb and lettuce cultivars. Our objective is to determine th ...
Supervisor: External supervisor(s) INFARM: Dr. Viviana Correa-Galvis, Pavlos Kalaitzoglou
Supervisor HPP: Dr. Elias Kaiser (1st contact)