Dionisio Andújar

• PostDoc Position at Spanish National Research Council

Weed competition in inter- and intra-row zones presents a substantial challenge to crop productivity, with intra-row weeds posing a particularly severe threat. Their proximity to crops and higher occlusion rates increase their negative impact on yields. This study examines the efficacy of advanced deep learning architectures—namely, Faster R-CNN, R...

Accurate assessment of forage quality is essential for ensuring optimal animal nutrition. Key parameters, such as Leaf Area Index (LAI) and grass coverage, are indicators that provide valuable insights into forage health and productivity. Accurate measurement is essential to ensure that livestock obtain the proper nutrition during various phases of...

Olive groves are one of the main agroecosystems in the Mediterranean region, but water erosion, aggravated by inappropriate soil management, is compromising the environmental sustainability of these crops. National and international public organisations, including the European Union via its Common Agricultural Policy, have acknowledged the problem...

Weeds negatively affect crop yield and quality by competing with the crop for resources. Detecting them in time allows us to optimize control through the precise application of herbicides and reduce their environmental impact. However, its detection and classification are challenging due to the great diversity of species and similarities with crops...

A system for automatically adjusting the angle of incidence of the tines of a harrow by processing nearby images allows the intensity of the treatment to be adapted in real time. In this study, precision agriculture technologies were implemented in a commercial implement to increase the selectivity of a mechanical treatment of weeds in cereal. The...

Weeds challenge crops by competing for resources and spreading diseases, impacting crop yield and quality. Effective weed detection can enhance herbicide application, thus reducing environmental and health risks. A major challenge in Site-Specific Weed Management (SSWM) is developing a reliable weed identification system, especially given the diver...

The Industrial Revolution changed the way of cropping with new machinery [...]

The olive groves’ relevance has historically been ingrained in Mediterranean cultures. Spain stands out as a leading producer worldwide, where olive trees are extensively grown in the Andalusian region. However, despite the importance of this strategic agricultural sector, cultivation through the years has given rise to various crop management prac...

As the tomato (Solanum lycopersicum L.) is one of the most important crops worldwide, and the conventional approach for weed control compromises its potential productivity. Thus, the automatic detection of the most aggressive weed species is necessary to carry out selective control of them. Precision agriculture associated with computer vision is a...

Agriculture is a field of activity characterized by physical labor, which is why many efforts are being made to introduce robotics on farms. In the specific case of vineyards, and harvesting, the difficulty lies in approximating the harvesting times of the grape harvester without damaging the product and consequently offering a cost-effective solut...

La agricultura es un ámbito de actividad caracterizado por el trabajo físico y por ello son muchos los esfuerzos para introducir la robótica en explotaciones agrícolas. En el caso específico de la recolección manual de frutas y hortalizas, y en particular en la vendimia, la dificultad radica en aproximarse a los tiempos de recolección del vendimiad...

Precision Agriculture face the challenge of feeding an increasing population, maximizing yield while optimizing inputs [...]

In the field of computer vision, 3D reconstruction of crops plays a crucially important role in agriculture. On-ground assessment of geometrical features of vineyards is of vital importance to generate valuable information that enables producers to take the optimum actions in terms of agricultural management. A training system of vines (Vitis vinif...

This chapter discusses advanced detection technologies for weed scouting. It starts by highlighting the current techniques that can be used to make optimizing herbicide treatments more efficient, such as on-ground and remotely sensed weed detection. The chapter then goes on to discuss the replacement of herbicide treatments for other control tactic...

El concepto de Gestión Integrada de Plagas (GIP) ha surgido en los últimos años con el fin de lograr un manejo sostenible de los cultivos reduciendo, entre otras cosas, la cantidad de agroquímicos empleados y con ello el impacto medioambiental. Un elemento clave es la monitorización o inspección continua de los cultivos para asegurar la detección t...

The adoption of site‐specific weed management (SSWM) technologies by farmers is not aligned with the scientific achievements in this field. While scientists have demonstrated significant success in real‐time weed identification, phenotyping and accurate weed mapping by using various sensors and platforms, the integration by farmers of SSWM and weed...

The increasing public concern about food security and the stricter rules applied worldwide concerning herbicide use in the agri-food chain, reduce consumer acceptance of chemical plant protection. Site-Specific Weed Management can be achieved by applying a treatment only on the weed patches. Crop plants and weeds identification is a necessary compo...

A non-destructive measuring technique was applied to test major vine geometric traits on measurements collected by a contactless sensor. Three-dimensional optical sensors have evolved over the past decade, and these advancements may be useful in improving phenomics technologies for other crops, such as woody perennials. Red, green and blue-depth (R...

Mechanical weed control in agriculture has advanced in terms of precision and working rate over the past years. The real-time communication of implements with sensor systems further increased the potential of mechanical weeding. There is a wide array of available sensors including image analysis by camera, GNSS, laser and ultrasonic systems that ca...

This chapter reviews the major conceptual approaches and specifications for the design of site-specific weed management decision support systems (SSWM-DSS), recent advances in the use of remote and ground platforms and sensors for information gathering and processing, and initial experiences translating this information into chemical and physical w...

In this study, aqueous extracts of Calliandra haematocephala Hassk. leaves and inflorescences were tested on seeds of quinoa (Chenopodium album L.) and rice (Oryza sativa L.), and on some of the most noxious-associated weeds, Chenopodium album L. and Holcus lanatus L. in quinoa, and Echinochloa crus-galli (L.) P. Beauv., Echinochloa colona L., Ecli...

Crop 3D modeling allows site-specific management at different crop stages. In recent years, light detection and ranging (LiDAR) sensors have been widely used for gathering information about plant architecture to extract biophysical parameters for decision-making programs. The study reconstructed vineyard crops using light detection and ranging (LiD...

This paper presents a novel approach for crop monitoring and 3D reconstruction. A mobile platform, based on a commercial electric vehicle, was developed and equipped with different on-board sensors for crop monitoring. Acceleration, braking and steering systems of the vehicle were automatized. Fuzzy control systems were implemented to achieve auton...

SPARKLE - Entrepreneurship for Sustainable Precision Agriculture (SPA) is a course aiming to increase 'agripreneurship' among students, entrepreneurs and academics, enhancing knowledge and skills on technologies, innovations, entrepreneurial thinking and problem-solving skills into the farming sector. It also aims to transform the agricultural sect...

SPARKLE - Entrepreneurship for Sustainable Precision Agriculture (SPA) is a course aiming to increase 'agripreneurship' among students, entrepreneurs and academics, enhancing knowledge and skills on technologies, innovations, entrepreneurial thinking and problem-solving skills into the farming sector. It also aims to transform the agricultural sect...

SPARKLE - Entrepreneurship for Sustainable Precision Agriculture (SPA) is a course aiming to increase 'agripreneurship' among students, entrepreneurs and academics, enhancing knowledge and skills on technologies, innovations, entrepreneurial thinking and problem-solving skills into the farming sector. It also aims to transform the agricultural sect...

SPARKLE - Entrepreneurship for Sustainable Precision Agriculture (SPA) is a course aiming to increase 'agripreneurship' among students, entrepreneurs and academics, enhancing knowledge and skills on technologies, innovations, entrepreneurial thinking and problem-solving skills into the farming sector. It also aims to transform the agricultural sect...

Plant modeling can provide a more detailed overview regarding the basis of plant development throughout the life cycle. Three-dimensional processing algorithms are rapidly expanding in plant phenotyping programmes and in decision-making for agronomic management. Several methods have already been tested, but for practical implementations the trade-o...

Aerial and on-ground vegetation characterization technologies are continuously evolving. An experiment was conducted in a vineyard field in order to test the economic feasibility of applying fertilizers site specifically based on different mapping systems. The capacity of UAV missions and on-ground systems has been compared using depth cameras or L...

Pastures are botanically diverse and difficult to characterize. Digital modeling of pasture biomass and quality by non-destructive methods can provide highly valuable support for decision-making. This study aimed to evaluate aerial and on-ground methods to characterize grass ley fields, estimating plant height, biomass and volume, using digital gra...

Poplar is considered one of the forest crops with greatest potential for lignocellulose production, so rapid and non-destructive measurements of tree growth (in terms of height and biomass) is essential to estimate productivity of poplar plantations. As an alternative to tedious and costly manual sampling of poplar trees, this study evaluated the a...

Sensing advances in plant phenotyping are of vital importance in basic and applied plant research. Plant phenotyping enables the modeling of complex shapes, which is useful, for example, in decision-making for agronomic management. In this sense, 3D processing algorithms for plant modeling is expanding rapidly with the emergence of new sensors and...

Weed monitoring is the first step in any site-specific weed management program. A relatively large variety of platforms, cameras, sensors and image analysis procedures are available to detect and map weed presence/abundance at various times and spatial scales. Remote sensing from satellites or aircrafts can provide accurate weed maps when the image...

Modern photographic imaging of agricultural crops can pin-point individual weeds, the patterns of which can be analyzed statistically to reveal how they are affected by variation in soil, by competition from other species and by agricultural operations. This contrasts with previous research on the patchiness of weeds that has generally used grid sa...

In this work, a crop inspection system is presented. A mobile platform, based on a commercial electric vehicle, is equipped with different on-board sensors to inspection annual crops (maize, cereal, etc.) and multi-annual crops (orchards, vineyards, etc.). The use of a low-cost RGB-D sensor, the Microsoft Kinect v2 sensor, for the inspection of woo...

Crop monitoring is an essential practice within the field of precision agriculture since it is based on observing, measuring and properly responding to inter- and intra-field variability. In particular, "on ground crop inspection" potentially allows early detection of certain crop problems or precision treatment to be carried out simultaneously wit...

This paper presents an inspection system integrated into an on-ground autonomous platform with range of approximately 80 km. The vehicle is prepared to autonomously cover a field following a predefined route plan. Two types of cameras were integrated in the platform. An RGB-D sensor and a reflex camera were placed in a fixture and connected to a hi...

New technologies, such as Differential Global Positioning Systems (DGPS) and Geographic Information Systems (GIS), may be useful in order to create models to predict the spatio-temporal behaviour of weeds. The aim of this study was to generate a geometric model able to predict the patch expansion of S. halepense, a problematic perennial weed in mai...

Weather conditions can affect sensors’ readings when sampling outdoors. Although sensors are usually set up covering a wide range of conditions, their operational range must be established. In recent years, depth cameras have been shown as a promising tool for plant phenotyping and other related uses. However, the use of these devices is still chal...

Weeds are one of the most important factors reducing productivity in poplar short-rotation coppices. Sorghum halepense is a very harmful perennial weed affecting irrigated crops preceding poplar plantations. The main goal of this study is to assess the potential hazards of residual S. halepense patches in newly established poplar crops and the effe...

This study evaluated the capabilities of a LiDAR-based system to characterize poplar trees for biomass production. The precision of the system was assessed by analyzing the relationship between the distance records and biophysical parameters. The terrestrial laser scanner (TLS) system consisted of a 2D time-of-flight LiDAR sensor, a gimbal to dynam...

Route planning in agricultural fields is a major challenge closely related to the amount of inputs consumed and the associated soil compaction. Current approaches primarily focus on reducing the travelled distances (i.e., the trajectories that vehicles have to cover to carry out the task) and generally do not consider other optimization criteria su...

The objective of this research was to explore the influence that weed decision threshold (DT; expressed as plants m⁻²), weed spatial distribution patterns, and spatial resolution of sampling have on potential reduction in herbicide use under site-specific weed management. As a case study, a small plot located in a typical corn field in central Spai...

The use of depth cameras in precision agriculture is increasing day by day. This type of sensor has been used for the plant structure characterization of several crops. However, the discrimination of small plants, such as weeds, is still a challenge within agricultural fields. Improvements in the new Microsoft Kinect v2 sensor can capture the detai...

In spatially heterogeneous weed infestations, variable dose technologies could be used to minimise herbicide use; high doses could be applied to reduce high-density patches and low doses to maintain weed populations in low-density portions of a field. To assess the potential short- and long-term effects of variable herbicide dose and site-specific...

The use of robotic systems for horticultural crops is widely known. However, the use of these systems in cruciferous vegetables remains a challenge. The case of cauliflower crops is of special relevance because it is a hand-harvested crop for which the cutting time is visually chosen. This methodology leads to a yield reduction, as some inflorescen...

The concept of precision agriculture, which proposes farming management adapted to crop variability, has emerged in recent years. To effectively implement precision agriculture, data must be gathered from the field in an automated manner at minimal cost. In this study, a small autonomous field inspection vehicle was developed to minimise the impact...

The challenge of weed harrowing is to obtain a high degree of weed control without producing considerable crop damage as a result of harrowing. Non-chemical weed control methods need to be directed towards a site-speciic weeding approach, in order to compete with conventional herbicide applications. In this study, an online automatic harrowing syst...

The overall objective of this study was to identify common patterns in the spatial distribution of the major weed species present in the corn-growing region of central Spain, exploring the scale dependence of these patterns and the possible associations or dissociations between individual species. Weed density was assessed in 16 commercial fields u...

The multi-angle plant reconstruction obtained from sensors such as Microsoft Kinect creates realistic models. However, a full 3D reconstruction from every angle is not possible at present under field conditions. When an on-the-go measurement is taken, the sensor must be fixed to a vehicle and its best position needs to be determined. The objective...

Crops intended for biomass production to be used as fuel in energy facilities, have gained importance in recent years due to its potential as a renewable energy source. Poplar (Populus spp.) is one of the most commonly used species as an energy crop in southern Europe due to its high production in high density plantations and short rotation. Weed c...

The sustained growth of the world's population in the coming years will require an even greater role for agriculture to meet the food needs of humankind. To improve the productivity and competitiveness of the agricultural industry, it is necessary to develop new and affordable sensing technologies for agricultural operations. This kind of innovatio...

In energy crops for biomass production a proper plant structure is important to optimize wood yields. A precise crop characterization in early stages may contribute to the choice of proper cropping techniques. This study assesses the potential of the Microsoft Kinect for Windows v.1 sensor to determine the best viewing angle of the sensor to estima...

Determining the best path planning for an agricultural task is a very important issue in crop management because it directly affects the distances travelled by the agricultural machines and, accordingly, directly affects the soil compaction that occurs and the inputs that are consumed (time and fuel). However, determining the optimal path is a diff...

Non-chemical weed control methods need to be directed towards a site-specific weeding approach, in order to be able to compete the conventional herbicide equivalents. A system for online weed control was developed. It automatically adjusts the tine angle of a harrow and creates different levels of intensity: from gentle to aggressive. Two experimen...

Non-destructive assessment of herbicide effects may be able to support integrated weed management. To test whether effects of herbicides on canopy variables could be detected by sensors, two crops were used as models and treated with herbicides at BBCH 20 using a logarithmic sprayer. Twelve days after spraying at BBCH 25 and 42 days after sowing, n...

Sorghum halepense (L.) Pers. is one of the most troublesome weeds in warm climates. Its control is difficult, and understanding the factors affecting its spreading is crucial. A study was conducted in 47 commercial maize fields, which account for more than 400 ha in the Spanish provinces of Albacete, Badajoz and Madrid, to analyse the distribution...

Site specific weed management (SSWM) is the part of Precision Agriculture (PA) that tries to effectively control weed infestations with the least economical and environmental burdens. This can be achieved with the aid of ground based or near range sensors in combination with decision rules and precise application technologies. Near range sensor tec...

In this study, the evaluation of the accuracy and performance of a light detection and ranging (LIDAR) sensor for vegetation using distance and reflection measurements aiming to detect and discriminate maize plants and weeds from soil surface was done. The study continues a previous work carried out in a maize field in Spain with a LIDAR sensor usi...

In this study, the evaluation of the accuracy and performance of a light detection and ranging (LIDAR) sensor for vegetation using distance and reflection measurements aiming to detect and discriminate maize plants and weeds from soil surface was done. The study continues a previous work carried out in a maize field in Spain with a LIDAR sensor usi...

A series of scenarios were assessed by simulating various weed decision thresholds (WDT) and different weed detection and herbicide application resolutions. Variable responses were obtained depending on the spatial distribution pattern of the weed. In the case of a patchy distributed species (Sorghum halepense), errors in spraying decision increase...

Spatial distribution of Sorghum halepense (L.) Pers. populations was assessed in tomato cropping fields in a total of 11 commercial fields (93 ha). Weed infestation was visually assessed from the cabin of a tractor after harvesting, using a three category ranking, ‘high’, ‘low’, and ‘no presence’, through infestation maps. Crop management factors a...

This study was conducted to assess the herbicide savings and the cost efficiency of site-specific herbicide application strategies in comparison with other strategies based on uniform application of herbicides throughout the whole field. The specific situation considered was Sorghum halepense infested maize fields in Spain. The results from a theor...

In this paper, we propose a new approach for discriminating maize and weed plants from soil surface, evaluating the accuracy and performance of a LiDAR sensor for vegetation detection using distance and reflection values. Field measurements were conducted in a maize field at growth stage BBCH 12-14. Static measurements were taken at different sampl...

The main idea of Site Specific Weed Management (SSWM) consists of adjusting herbicide treatments depending on the infested area and the type of weed. In this context, the discrimination between grasses (monocots) and broad-leaved weeds (dicots) is an important objective mainly because the two weed groups can be controlled by different specific herb...

This study describes the spatial distribution patterns of seven species considered among the major weeds in maize crops in Central Spain. In addition, spatial association among weed species was also analysed. Visual assessments of the density of Abutilon theophrasti, Amaranthus spp., Cyperus rotundus, Datura ferox, Solanum nigrum, Sorghum halepense...

Harrowing is often used to reduce weed competition, generally using a constant intensity across a whole field. The efficacy of weed harrowing in wheat and barley can be optimized, if site-specific conditions of soil, weed infestation and crop growth stage are taken into account. This study aimed to develop and test an algorithm to automatically adj...

LiDAR (Light Detection And Ranging) is a remote-sensing technique for the measurement of the distance between the sensor and a target. A LiDAR-based detection procedure was tested for characterisation of the weed vegetation present in the inter-row area of a maize field. This procedure was based on the hypothesis that weed species with different he...

In this work, we evaluate the role of agronomic factors in the selection for herbicide resistance in Apera spica-venti L. Beauv. (silky windgrass). During a period of three years, populations were collected in more than 250 conventional fields across Europe and tested for resistance in the greenhouse. After recording the field history of locations,...

Many different sensors have been proposed to estimate plant status parameters like nutrition status, coverage or plant size. Such parameters are key factors for precise management. This study combined four different sensors in a field trial with spring barley and oil seed rape. The following commercial sensors were used: LiDAR, spectrometer, ultras...

La idea principal de control específico de mala hierba consiste en ajustar los tratamientos de herbicidas en función de la zona infestada y el tipo de mala hierba. En este contexto, la discriminación entre las gramíneas (monocotiledóneas) y malas hierbas de hoja ancha (dicotiledóneas) es un objetivo importante sobre todo porque los dos grupos de ma...

Site-specific weed management requires sensing of the actual weed infestation levels in agricultural fields to adapt the management accordingly. However, sophisticated sensor systems are not yet in wider practical use, since they are not easily available for the farmers and their handling as well as the management practice requires additional effor...