At the Center for Virtual Plant Imaging in the Netherlands, plants are now viewed from all sides using cameras, sensors, robots and automated systems in intermediates, climate cells, greenhouses, and in the field.
When tomato plants are taken out of their greenhouses, they are placed on conveyor belts and briefly disappear into a detection box where camera systems record them from all sides. After that, each receives pre-programmed amounts of water and nutrients. In another greenhouse, cyclamen stand at fixed distances but are regularly checked by a flying camera robot that records information about their plant geometry and floral development from all angles.
“Building these unique facilities has been a long journey and at times has taken us as scientists outside our comfort zone. But it opens up a whole new world: we get access to root and canopy development, from very small to very large. It allows us to answer very interesting agricultural and ecological questions, Wageningen plant geneticist Mark Arts, head of the NPEC management team as well as the lead applicant for a grant of over €11 million, says Wageningen & Research University and the University of Utrecht jointly invest the amount in the centre, whose facilities are also available for experiments by researchers from universities other,
“This is Botany 2.0, because it offers completely new possibilities,” explains Arts. We already have a good understanding of genetics. An entire genome of Arabidopsis you can sequence for a few dollars these days. But it takes a long time to determine exactly what these differences in DNA mean for a plant’s phenotype. We have all the technologies from genomics to metabolism, but the most important in the end are the changes that occur in the phenotype of the plant. This phenotype also changes over time and is the end result of gene expression. What is the effect of environmental factors such as light, humidity, and temperature on plant growth, and what role does pathogens or the microbiome play in this? We are entering a new era with automated phenotype. “Now the researcher is really full of having a good data set sometime after the experiment, but with NPEC facilities, this can be done for a few moments,” says Arts.
Artes conducted genetic research years ago into the adaptation of plants to unfavorable environmental conditions in typical species of cress (Arabidopsis thaliana) and zinc burdock (Noccaea caerulescens). In particular, to look at the effects of the environment on photosynthesis, he has already developed the first high-throughput automated phenotyping platform: the Phenovator. At the time, it already had an unprecedented ability and could screen 1,440 Arabidopsis plants several times a day for photosynthesis, growth and spectral reflectance at eight wavelengths (Plant Methods, 2016).
The new NPEC modules enable us to almost continuously monitor the impact of various stressors on plant development, both underground and above ground, from seedlings to potted plants and even crops in the field. Plus, thanks to inversion and fluorescence techniques, we can make observations down to the level of components and physiological responses of plants, says Arts. In the greenhouse, tomatoes enter the unit through a conveyor belt system, in contrast to units where plants are stationary, and metering systems move. “We know that movement affects the development of plants, so this at least gives us the opportunity to address this,” explains Arts.
“This is really the cream of the crop for botanists,” says Utrecht biologist Roeland Berendsen, a researcher in the Plant-Microbe Interactions group and director of the Institute for Environmental Biology. Almost all environmental conditions can be adjusted in smaller climate rooms. From frost to temperatures above 40 degrees and from light intensity to full sunlight, it reaches ten times higher than normal in climatic rooms. It has nine colors of LED light. Perfect for researching the effect of shade on plants. It can accommodate all kinds of plants: especially Arabidopsis and tomatoes, but preferably no corn, Berendsen smiles.
Also impressive are the 36 Mediterranean models or ecotrons already in the NPEC building under construction. These are the units in which half a cubic meter of soil can be introduced and planted with the desired vegetable plants. When the valve is closed, the soil temperature, lighting and indoor air composition can be fully controlled. According to Berendsen, this is an ideal setup for testing, for example, under rigorous conditions the interactions discovered in the large-scale, long-term BioCliVE experiment—the Biodiversity and Climate Change Experiment—with outdoor vegetation.