Gerrit Polder

• PhD
• Researcher at Wageningen University & Research

Downy mildew ( Plasmopara ), apple scab ( Venturia inaequalis ), and Alternaria leaf blight are endemic diseases that affect crops worldwide. The diseases can cause severe losses in grapes, apples and carrots when not detected and treated in an early stage. The European Union Horizon 2020 OPTIMA project aimed to improve disease detection in the ope...

Fusarium head blight (FHB) is a plant disease caused by various species of the Fusarium fungus. One of the major concerns associated with Fusarium spp. is their ability to produce mycotoxins. Mycotoxin contamination in small grain cereals is a risk to human and animal health and leads to major economic losses. A reliable site-specific precise Fusar...

Background The study of plant photosynthesis is essential for productivity and yield. Thanks to the development of high-throughput phenotyping (HTP) facilities, based on chlorophyll fluorescence imaging, photosynthetic traits can be measured in a reliable, reproducible and efficient manner. In most state-of-the-art HTP platforms, these traits are a...

The increasing complexity of greenhouse production systems requires the step to a more data-driven approach that is based on robust, intelligent sensors. Whereas climate sensors are widely available in greenhouse systems, control based on crop data is still in its infancy. There is a clear need among growers to monitor the status of the crop in the...

Flower color is one of the most important traits in horticulture, and is one of the characteristics recorded to describe new varieties. In this paper, we examine four large real-world databases of roses and gerberas containing both images and color descriptions, and use state-of-the-art methods to automatically extract color descriptions from the i...

A phenotyping pipeline utilising DeepLab was developed for precisely estimating the height, volume, coverage and vegetation indices of European and Japanese varieties. Using this pipeline, the effect of varying UAV height on the precise estimation of potato crop growth properties was evaluated. A UAV fitted with a multispectral camera was flown at...

Apple scab is a fungal disease caused by Venturia inaequalis. Disease is of particular concern for growers, as it causes significant damage to fruit and leaves, leading to loss of fruit and yield. This article examines the ability of deep learning and hyperspectral imaging to accurately identify an apple symptom infection in apple trees. In total,...

Soil composition and herbivory are two environmental factors that can affect plant traits including flower traits, thus potentially affecting plant‐pollinator interactions. Importantly, soil composition and herbivory may interact in these effects, with consequences for plant fitness. We assessed the main effects of aboveground insect herbivory and...

A typical problem when using deep neural networks in the domain of agriculture is the limited availability of labelled training data. Generative adversarial networks (GAN) hold the potential that they can learn to create realistic fake images, which might be used to enrich the training set. In this research, the added value of image augmentation us...

Forcing tulips is a process that mimics the conditions of winter and early spring in a controlled environment to make the tulips bloom months earlier than they would if grown in the open field. In this process, it is essential that the relative humidity in the growing environment is kept sufficiently low. Otherwise, there is an increased risk of th...

Tomato is an important food product for which the development of non-destructive quality assessment methods is of great interest. Using visible and near-infrared (NIR) spectroscopy, the sugar content, acidity and even taste can be estimated through the use of chemometric methods (e.g., partial least squares regression). In the case of reflection sp...

Spectral imaging (SI) in analytical chemistry is widely used for the assessment of spatially distributed physicochemical properties of samples. Although massive development in instrument and chemometrics modelling has taken place in the recent years, the main challenge with SI is that available sensors require extensive system integration and calib...

This study aims to utilize non-destructive sensing based on Vis-NIR spectroscopy and acoustic to predict firmness of avocado fruit. The study has three aims, the first aim was to find the best reference firmness measurement technique for calibrating Vis-NIR spectroscopy data related to avocado ripening i.e., acoustic firmness (AF), limited compress...

High-throughput phenotyping is playing an increasingly important role in many areas of agriculture. Breeders will use it to obtain values for the traits of interest so that they can estimate genetic value and select promising varieties; growers may be interested in having predictions of yield well in advance of the actual harvest. In most phenotypi...

Close-range spectral imaging (SI) of agricultural plants is widely performed for digital plant phenotyping. A key task in digital plant phenotyping is the non-destructive and rapid identification of drought stress in plants so as to allow plant breeders to select potential genotypes for breeding drought-resistant plant varieties. Visible and nearin...

Close range spectra imaging of agricultural plants is widely performed to support digital plant phenotyping, a task where physicochemical changes in plants are monitored in a non-destructive way. A major step before analyzing the spectral images of plants is to distinguish the plant from the background. Usually, this is an easy task and can be perf...

p>Timely detection of water stress in agricultural crops is important. In this paper, a smart classification algorithm was developed to detect water stress in tomato plants that were grown in the greenhouse. During the growth period, thermal and visible light images were acquired from the canopy tops in two states: (1) plants in normal conditions;...

Accurately detecting and counting fruits during plant growth using imaging and computer vision is of importance not only from the point of view of reducing labor intensive manual measurements of phenotypic information, but also because it is a critical step toward automating processes such as harvesting. Deep learning based methods have emerged as...

p>In greenhouse horticulture, efficiency of climate control and plant protection can be improved by having an accurate impression of plant status, such as photosynthesis or chemical composition. Recent advances in remote sensing technologies have brought about a range of innovations in precision agriculture, with the potential for adaptation to gre...

Spectroscopy Non-destructive Visible and near-infrared spectral imaging is a key non-destructive technique for rapid assessment of biophysical traits of plants. A major challenge with close-range spectral imaging of plants is spectral variation arising from illumination effects, which may mask the signals due to physiochemical differences. In the p...

In this paper we propose an image analysis method for detecting and counting tomato flowers from images taken in a greenhouse. Detecting and locating flowers is useful information for tomato growers and breeders, for phenotyping, yield prediction, and for automating procedures such as pollination and spraying. Since the tomato flowers are yellow, w...

Purpose of Review A short introduction to the spectral imaging (SI) of plants along with a comprehensive overview of the recent research works related to disease detection in plants using autonomous phenotyping platforms is provided. Key benefits and challenges of SI for plant disease detection on robotic platforms are highlighted. Recent Findings...

Hyperspectral imaging is currently a very well-known and much used technology for measuring features in different fields, such as chemistry, geology, medicine, food and agriculture, either spaceborne (satellites), airborne (drones) or at close proximity (e.g. field scanning, industrial sorting lines or microscopy). Its background is two-fold, and i...

OPTIMA-Optimised Pest Integrated Management to precisely detect and control plant diseases in perennial crops and open-field vegetables (http://optima-h2020.eu/). An EU project financed under H2020 (ID: 773718) program, which is composed of a consortium of 17 partners led by the Agricultural University of Athens, Greece. The objective of this proje...

In this paper we propose an image analysis method for detecting and counting tomato flowers from images taken in a greenhouse. Detecting and locating flowers is useful information for tomato growers and breeders, for phenotyping, yield prediction, and for automating procedures such as pollination and spraying. Since the tomato flowers are yellow, w...

OPTIMA is an H2020 research project that will develop an environmentally friendly IPM framework for vineyards, apple orchards and carrots by providing a holistic integrated approach which includes all critical aspects related to integrated disease management, such as i) use of novel biological Plant Protection Products, ii) disease prediction model...

Virus diseases are of high concern in the cultivation of seed potatoes. Once found in the field, virus diseased plants lead to declassification or even rejection of the seed lots resulting in a financial loss. Farmers put in a lot of effort to detect diseased plants and remove virus-diseased plants from the field. Nevertheless, dependent on the cul...

Plant phenotypic plasticity in response to antagonists can affect other community members such as mutualists, conferring potential ecological costs associated with inducible plant defence. For flowering plants, induction of defences to deal with herbivores can lead to disruption of plant‐pollinator interactions. Current knowledge on the full extent...

Potato blackleg is a tuber-borne bacterial disease caused by species within the genera Dickeya and Pectobacterium that can cause decay of plant tissue and wilting through the action of cell wall degrading enzymes released by the pathogen. In case of serious infections, tubers may rot before emergence. Management is largely based on the use of patho...

Tulip crop production in the Netherlands suffers from severe economic losses caused by virus diseases such as the Tulip Breaking Virus (TBV). Infected plants which can spread the disease by aphids must be removed from the field as soon as possible. As the availability of human experts for visual inspection in the field is limited, there is an urgen...

Plant disease detection represents a tremendous challenge for research and practical applications. Visual assessment by human raters is time-consuming, expensive, and error prone. Disease rating and plant protection need new and innovative techniques to address forthcoming challenges and trends in agricultural production that require more precision...

Nondestructive methods are of utmost importance for honey characterization. This study investigates the potential application of VIS-NIR hyperspectral imaging for detection of honey flower origin using machine learning techniques. Hyperspectral images of 52 honey samples were taken in transmittance mode in the visible/near infrared (VIS-NIR) range...

In this paper we present a novel method for automated detection of Mycosphaerella melonis infected cucumber fruits. The two-step method consists of machine learning approach using: shape based features extracted from cucumber color images and light transmission spectra based features. The automated detection rate was compared to the manual detectio...

This study investigates the application of hyperspectral imaging system and data mining based classifiers for honey adulteration detection. Hyperspectral images from pure and adulterated samples were captured in using a VIS-NIR hyperspectral camera (400 – 1000 nm). After preprocessing the images, five different data mining based techniques, includi...

Introduction: Metabolomics has become a valuable tool in many research areas. However, generating metabolomics-based biochemical profiles without any related bioactivity is only of indirect value in understanding a biological process. Therefore, metabolomics research could greatly benefit from tools that directly determine the bioactivity of the d...

Image-based plant phenotyping is a growing application area of computer vision in agriculture. A key task is the segmentation of all individual leaves in images. Here we focus on the most common rosette model plants, Arabidopsis and young tobacco. Although leaves do share appearance and shape characteristics, the presence of occlusions and variabil...

Een machine-vision-setup en bijbehorende analyse software zijn in ontwikkeling voor het meten van tripsschade in chrysantenbladeren.

High throughput plant phenotyping facilities are rapidly becoming essential for significant advancements in plant breeding. Wageningen ur combines all of the necessary expertises in Phenomics nl and is involved in several (inter) national phenotyping initiatives to lead and explore the field of plant phenomics.

In this chapter, an overview of different plant features is given, from (sub) cellular to canopy level. A myriad of methods is available to measure these features using image analysis, and often, multiple methods can be used to measure the same feature. Several criteria are listed for choosing a certain (set of) image descriptor(s) to measure a pla...

Leaf area measurements are commonly obtained by destructive and laborious practice. This study shows how stereo and time-of-flight (ToF) images can be combined for non-destructive automatic leaf area measurements. The authors focus on some challenging plant images captured in a greenhouse environment, and show that even the state-of-the-art stereo...

High-throughput automated plant phenotyping has recently received a lot of attention. Leaf area is an important characteristic in understanding plant performance, but time-consuming and destructive to measure accurately. In this research, we describe a method to use a histogram of image intensities to automatically measure plant leaf area of tall p...

In our post-genomic world, where we are deluged with genetic information, the bottleneck to scientific progress is often phenotyping, i.e. measuring the observable characteristics of living organisms, such as counting the number of fruits on a plant. Image analysis is one route to automation. In this paper we present a method for recognising and co...

Tulip breaking virus (TBV) causes severe economic losses in flower bulbs in the Netherlands. To prevent further spread by aphids, the vector of the disease, infected plants must be removed from the field as soon as possible. Until now screening has been carried out by visual inspection in the field. As the availability of human experts is limited t...

Tulpenmozaїekvirus (TBV) in tulp veroorzaakt veel schade in de teelt. Om virusverspreiding door bladluizen te voorkomen moet de teler in een korte periode deze bronnen van infectie verwijderen. Een tijdrovende bezigheid, die ook specifieke deskundigheid vergt. Verder bespaart dit verwijderen ook het gebruik van gewasbeschermingsmiddelen om de luize...

Plant phenotyping is an emerging science that links genomics with functional plant characteristics. The recent availability of extremely fast high-throughput genotyping technologies has invoked high-throughput phenotyping to become a major bottleneck in the plant breeding programs. As a consequence new camera-based technologies to relieve the pheno...

Tulip breaking virus (TBV) causes severe economic losses in flower bulbs in the Netherlands. To prevent further spread by aphids, infected plants must be removed from the field as soon as possible. Until now screening is done by visual inspection in the field. As the availability of human experts is limited there is an urgent need for a rapid, auto...

In the Interreg IV, EU project 'The healthy greenhouse' a new integral crop protection system is developed. Part of the project is the development of autonomous robots for monitoring individual plants. One of the sensors for monitoring is an application- specific multispectral camera for detection of fungal diseases. In this paper the development o...

Tulpenmozaїekvirus (TBV) in tulp veroorzaakt veel schade in de teelt. Om virusverspreiding door bladluizen te voorkomen moet de teler in een korte periode deze bronnen van infectie verwijderen. Een tijdrovende bezigheid, die ook specifieke deskundigheid vergt. Verder bespaart dit verwijderen ook het gebruik van gewasbeschermingsmiddelen om de luize...

Tulip breaking virus (TBV) causes severe economic losses for the Netherlands. Infected plants must be removed from the field as soon as possible to prevent further spread by aphids. Until now screening is done by visual inspection in the field. As the availability of human experts is limited there is an urgent need for a rapid, automated and object...

Most high-throughput systems for automated plant phenotyping involve a fixed recording cabinet to which plants are transported. However, important greenhouse plants like pepper are too tall to be transported. In this research we developed a system to automatically measure plant characteristics of tall pepper plants in the greenhouse. With a device...

Een vroege detectie van zieke planten met moderne vision technieken kan de kosten voor selectie in de pootaardappelteelt flink drukken. De nadruk ligt hierbij op de detectie van Erwinia, gezien de grote financiële schade. In 2010 zijn een eerste serie metingen in pootaardappelen uitgevoerd met een bestaande opstelling voor detectie van viruszieke t...

Dit onderzoek was gericht op het vinden van de meest geschikte opnametechniek voor het ziekzoeken, waarmee een eenduidig onderscheid te maken is tussen zieke en niet-zieke planten. Een belangrijk accent lag op het vroegtijdig herkennen van zieke planten. De nieuwe technologieën hebben vooral meerwaarde als het herkennen mogelijk wordt voordat de sy...

Ziekzoeken (het door experts in het veld laten zoeken naar symptomen in het gewas) wordt toegepast bij verschillende (bol-) gewassen om vroegtijdig besmettingen op te sporen en door vernietiging in te perken. Dit betreft naast virus in tulp onder andere ook geelziek in hyacint. Dit is een makkelijk verspreidbare bacterieziekte, veroorzaakt door Xan...

Er wordt al een paar jaar onderzoek gedaan naar het automatiseren van het ziekzoeken in de tulp: met camera's en software zoeken naar symptomen van de ziekte. Hyacintentelers hebben ook belangstelling voor geautomatiseerd ziekzoeken naar geelzieksymtomen ("spetters"). Met twee studenten van TU Eindhoven is een beknopte studie uitgevoerd om spetters...

For plant variety testing many plant characteristics need to be measured to assess distinctness between varieties and uniformity and stability of a variety. The characteristics are described in guidelines and protocols for each crop. These guidelines are established by international organizations. Several characteristics, related to shape and form...

This paper shows how stereo and Time-of-Flight (ToF) images can be combined to estimate dense depth maps in order to automate plant phenotyping. We focus on some challenging plant images captured in a glasshouse environment, and show that even the state-of-the-art stereo methods produce unsatisfactory results. By developing a geometric approach whi...

Broad-leaved dock is a common and troublesome grassland weed with a wide geographic distribution. In conventional farming the weed is normally controlled by using a selective herbicide, but in organic farming manual removal is the best option to control this weed. The objective of our work was to develop a robot that can navigate a pasture, detect...

Tulpenmozaïekvirus (TBV) veroorzaakt jaarlijks veel schade in tulpen. Vooral in de witte en gele cultivars is de afkeur groot. Om de virusdruk te verminderen worden in de praktijk door ziekzoekers viruszieke tulpen uit het veld verwijderd. Het is moeilijk ervaren ziekzoekers te vinden. Daarom is onderzoek gedaan naar een oplossing waarbij virusziek...

In 2008 is het project Ziekzoeken in tulp gestart na een succesvol laboratoriumexperiment. In 2009 bleek de overgang van laboratorium naar een handmatig bediend prototype in het veld een te grote stap. In 2010 zijn de camera's, belichting en uitvoering van de ziekzoekrobot aangepast. Uit de resultaten in 2010 bleek dat een verdere verbetering van d...

Ripening of tomatoes is a combination of processes including the breakdown of chlorophyll and build-up of carotenes. Chlorophyll and carotenes have specific, well-known reflection spectra. Using knowledge of the known spectral properties of the main constituent compounds, it may be possible to calculate their concentrations using spectral measureme...

Experiments are described for detection of Tulip Breaking Virus in tulip plants. Four optical techniques were investigated and compared with visual assessment by crop experts as well as with Elisa (Enzyme ImmunoAssay) analysis of the same plants. The optical sensor techniques used were: an RGB Color camera, a spectrophotometer ranging from 400-2400...

Ridderzuring (Rumex obtusifolius L.) is een veelvoorkomend en lastig te bestrijden onkruid dat vooral biologische melkveehouders grote problemen bezorgt. Op initiatief van de sector wordt daarom een robot ontwikkeld die geheel zelfstandig ridderzuring opspoort en vernietigt.

De teelt van tulpen kampt met aantasting door verschillende virussen, die de opbrengst en de kwaliteit verlagen en een belemmering zijn voor de export. Bij een hoge besmetting worden hele partijen afgekeurd. In 2009 is vervolgens een uitgebreid veldonderzoek uitgevoerd. Hierbij is met een eerste prototype ziekzoekrobot door een aantal proefveldplot...

Tulpenmozaïekvirus (tulip breaking virus - TBV) veroorzaakt jaarlijks veel economische schade in tulpen. Vooral in witte en gele tulpencultivars is de afkeur groot, daar hier de symptomen moeilijk zichtbaar zijn en de benodigde visuele expertise om de subtiele virusbeelden te zien nog maar beperkt aanwezig is bij de tulpentelers. In een laboratoriu...

The objective of plant phenotyping studies is to understand the relationship between a plant’s genotype and phenotype. In our study we focus on the leaf morphology of Arabidopsis seedlings. Our experimental setup consists of a table of 0.9 m × 3.8 m with a matrix of about 1500 small cubes of rockwool, each containing an Arabidopsis seedling with a...

Volunteer potato is a perennial weed that is difficult to control in crop rotations. It was our objective to build a small, low-cost robot capable of detecting volunteer potato plants in a cornfield and thus demonstrate the potential for automatic control of this weed. We used an electric toy truck as the basis for our robot. We developed a fast ro...

van E vert FK, P older G, van der H eijden GWAM, K empenaar C & L otz LAP (2009). Real‐time vision‐based detection of Rumex obtusifolius in grassland. Weed Research 49 , 164–174. Summary Rumex obtusifolius is a common grassland weed that is hard to control in a non‐chemical way. The objective of our research was to automate the detection of R. obt...

This paper presents the development of a mathematical model to predict the perception of naturalness for a range of materials, based on an understanding of the relationship between the physical attributes of the material and the human sensory inputs. The work is being carried out under an European Union project called 'Measurement of Naturalness' (...

Experiments are described for detection of Tulip Breaking Virus in tulip plants. Four optical techniques were investigated and compared with visual assessment by crop experts as well as with Elisa (Enzyme ImmunoAssay) analysis of the same plants. The optical sensor techniques used were: an RGB Color camera, a spectrophotometer ranging from 400-2400...

Broad-leaved dock (Rumex obtusifolius L.) is a common and troublesome grassland weed with a wide geographic distribution. In organic farming, the best option to control the weed is manual removal of the plants. In this report we describe the development and first tests of a robot to detect and control broad-leaved dock. An analysis of requirements...

Introduction The EU project SPICY (Smart tools for Prediction and Improvement of Crop Yield) aims to develop a suite of tools for molecular breeding of crop plants for sustainable and competitive agriculture. The tools help the breeder in predicting phenotypic response of genotypes for complex traits under a range of environmental conditions. Peppe...

Het vinden van viruszieke tulpen in het veld is een moeilijke klus, zelfs geroutineerde ziekzoeker heeft moeite met vooral de gele en witte cultivars. Met gevoelige cameratechnieken lijkt het mogelijk te zijn om het ziekzoeken te automatiseren. Op initiatief van tulpenteler Piet Apeldoorn zijn PPO en PRI aan de slag gegaan

Driven by the success of the previous events in Wageningen in 2003, 2004 and 2005 and the Field Robot Event hosted by Hohenheim University in Stuttgart, Germany in 2006, Wageningen University organized the 5th Field Robot Event on June 14-16, 2007. This event was accompanied by a workshop and a fair where the teams were able to present their robots...

Stress in plants can be measured using chlorophyll fluorescence imaging. The development of patterns in time can give an indication of the type of stress. Since leaves grow and show leaf movements, there is no pixel to pixel correspondence in time laps imaging data. In this article, Penalized Likelihood Warping and Robust Point Matching methods for...

The objective of the work described here was to detect broad-leaved weeds in grassland. We used textural image analysis to detect weeds in grass. In the textural analysis, images were divided in square tiles, which were subjected to a 2-D FFT. The power of the resulting spectrum was found to be a measure of the presence of coarse elements (weeds)....

Fusarium head blight (FHB) is a harmful fungal disease that occurs in small grains. Non-destructive detection of this disease is traditionally done using spectroscopy or image processing. In this paper the combination of these two in the form of spectral imaging is evaluated. Transmission spectral images are recorded, both in the visible and near-i...

Tomatoes (Lycopersicum esculentum, Mill. cv. Capita F1) were harvested at different ripening stages. Spectral images from 400 to 700 nm with a resolution of 1 nm were recorded. After recording, samples were taken from the fruit wall and the lycopene, lutein, -carotene, chlorophyll-a and chlorophyll-b concentrations were measured using HPLC. The rel...