Ana I. De Castro

• Ph. D. Forestry Engineer
• Researcher at Centro Nacional Instituto de Investigación y Tecnología Agraria y Alimentaria CSIC

Water stress is a critical factor affecting the health and productivity of ornamental plants, yet early detection remains challenging. This study aims to investigate the spectral responses of four ornamental plant taxa—Rosa hybrid (rose), Itea virginica (itea), Spiraea nipponica (spirea), and Weigela florida (weigela)—under varying levels of water...

Identifying weed species at early-growth stages is critical for precision agriculture. Accurate classification at the species-level enables targeted control measures, significantly reducing pesticide use. This paper presents a dataset of RGB images captured with a Sony ILCE-6300L camera mounted on an unmanned aerial vehicle (UAV) flying at an altit...

Purpose High resolution imagery from unmanned aerial vehicles (UAVs) has been established as an important source of information to perform precise irrigation practices, notably relevant for high value crops often present in semi-arid regions such as vineyards. Many studies have shown the utility of thermal infrared (TIR) sensors to estimate canopy...

Early detection of weeds is crucial to manage weeds effectively, support decision-making and prevent potential crop losses. This research presents an innovative approach to develop a specialized cognitive system for classifying and detecting early-stage weeds at the species level. The primary objective was to create an automated multiclass discrimi...

Accurate weed species identification is crucial for effective site-specific weed management (SSWM), enabling targeted and timely control measures for each weed in crop field. This study advanced the current approach to species-level weed identification during the early growth stage by integrating unmanned aerial vehicles (UAVs) imagery with standar...

Precise irrigation management requires accurate knowledge of crop water demand to adequately optimize water use efficiency, especially relevant in arid and semi-arid regions. While unoccupied aerial vehicles (UAV) have shown great promise to improve the water management for crops such as vineyards, there still remains large uncertainties to accurat...

Sorghum halepense (Johnsongrass) is a weed that tends to spatially distribute in an aggregated manner in maize crops. In a two-year study conducted at La Poveda (CSIC, Madrid), the effectiveness of Precision Agriculture (PA) in controlling this weed was investigated by: 1) monitoring the spatio-temporal dynamics of Johnsongrass patches in a maize f...

Accurate detection and identification of weeds are essential in the implementation of Precision Agriculture (PA). In this study, we addressed the detection and classification of weeds in maize and tomato in their early growth stages by integrating images acquired from UAVs and analysis based on advanced convolutional neural networks. Subsequently,...

Currently, there is technology available to develop treatments at variable rates on crops. The difficulty is to properly identify the weed species and thus be able to adjust the doses of herbicide to the species present at each point of the plot. For this reason, the objective of this work is to carry out a field trial to study the potential of the...

Efficient invasive weed management is critical to maintain the balance between biodiversity, production and agricultural sustainability. Invasive plants may cause significant yield losses in crops and their control entails a high cost in pesticide products, in addition to the ecological damage they generate. Advances in robotics, digital agricultur...

This work presents the results of an outdoor intercomparison experiment where the reflectance factors from five full-range field spectroradiometers (400-2500 nm) were compared using repeatability, reproducibility, and compatibility metrics. We confronted four Analytical Spectral Devices (ASD) and one Spectravista Corporation (SVC) sensor. Ancillary...

Characterizing crop canopies is especially important in the management of woody crops. In this article, two systems were compared to characterise a 50 m long vineyard row section. One of the systems was a mobile terrestrial laser scanner based on a light detection and ranging (LiDAR) sensor (MTLS-LiDAR). The other was an uncrewed aerial vehicle (UA...

The measurement of geometric canopy parameters in woody crops is an important task in Precision Agriculture because of their correlation with crop condition and productivity. In recent years, several technological approaches have been developed as an alternative to manual measurements, which are time-and labour-consuming. Two of the most commonly u...

Crop protection is a key activity for the sustainability and feasibility of agriculture in a current context of climate change, which is causing the destabilization of agricultural practices and an increase in the incidence of current or invasive pests, and a growing world population that requires guaranteeing the food supply chain and ensuring foo...

Los recientes avances en digitalización y algoritmos de análisis de imágenes ofrecen la oportunidad de identificar especies arvenses en imágenes aéreas de alta resolución espacial adquiridas desde drones, aunque para ello es necesario nutrir al sistema con una completa base de datos de entrenamiento y determinar sus características óptimas. En este...

Many endeavours in precision agriculture use some kind of sensor to gain relatively inexpensive information on the spatial and temporal variation in crops, soil, weeds, diseases, and so on. However, information about sensors is scattered throughout the literature. This text fills an important niche by bringing together information on a wide range o...

The potential loss of world crop production from the effect of pests, including weeds, animal pests, pathogens and viruses has been quantified as around 40%. In addition to the economic threat, plant diseases could have disastrous consequences for the environment. Accurate and timely disease detection requires the use of rapid and reliable techniqu...

Global plant production faces the major challenge of sustainability under the constraint of a rapidly growing world population and the gradual depletion of natural resources. Remote sensing can play a fundamental role in changing the production model through the development and implementation of new technologies for vegetation monitoring (e.g., adv...

The purpose of this research is to examine and monitor factors affecting peach cultivation as a part of an overall research program for developing Integrated Pest Management strategies. Potassium fertilization and the practice of root-collar excavation have proven effective in increasing yield and fruit quality and in extending orchard longevity on...

This paper reviewed a set of twenty-one original and innovative papers included in a special issue on UAVs for vegetation monitoring, which proposed new methods and techniques applied to diverse agricultural and forestry scenarios. Three general categories were considered: (1) sensors and vegetation indices used, (2) technological goals pursued, an...

Significant advances in weed mapping from unmanned aerial platforms have been achieved in recent years. The detection of weed location has made possible the generation of site specific weed treatments to reduce the use of herbicides according to weed cover maps. However, the characterization of weed infestations should not be limited to the locatio...

Airborne methodologies based on unmanned aerial vehicles (UAV) are becoming an extraordinary tool for implementing fast, accurate and affordable phenotyping strategies within plant breeding programs. The aim of this paper was to study the potential use of a previously developed UAV-OBIA platform, to fasten and support decision making for olive bree...

Canopy management operations, such as shoot thinning, leaf removal, and shoot trimming, are among the most relevant agricultural practices in viticulture. However, the supervision of these tasks demands a visual inspection of the whole vineyard, which is time-consuming and laborious. The application of photogrammetric techniques to images acquired...

Remote sensing applied in the digital transformation of agriculture and, more particularly, in precision viticulture offers methods to map field spatial variability to support site-specific management strategies; these can be based on crop canopy characteristics such as the row height or vegetation cover fraction, requiring accurate three-dimension...

Background: Almond is an emerging crop due to the health benefits of almond consumption including nutritional, anti-inflammatory, and hypocholesterolaemia properties. Traditional almond producers were concentrated in California, Australia, and Mediterranean countries. However, almond is currently present in more than 50 countries due to breeding p...

The establishment and management of cover crops are common practices widely used in irrigated viticulture around the world, as they bring great benefits not only to protect and improve the soil, but also to control vine vigor and improve the yield quality, among others. However, these benefits are often reduced when cover crops are infested by Cyno...

The need for the olive farm modernization have encouraged the research of more efficient crop management strategies through cross-breeding programs to release new olive cultivars more suitable for mechanization and use in intensive orchards, with high quality production and resistance to biotic and abiotic stresses. The advancement of breeding prog...

As demand for freshwater increases while supply remains stagnant, the critical need for sustainable water use in agriculture has led the EPA Strategic Plan to call for new technologies that can optimize water allocation in real-time. This work assesses the use of cloud-based artificial intelligence to detect early indicators of water stress across...

Accurately mapping the spatial distribution of weeds within a field is a first step towards effective Site-specific Weed Management. The main objective of this study was to investigate if the multivariate geostatistical method of cokriging (COK) can be used to improve the accuracy of Papaver rhoeas L. infestations maps in winter wheat fields using...

Los avances tecnológicos tienen la capacidad de cambiar substancialmente los procesos de producción agraria, permitiendo la realización de las tareas agrícolas con mayor eficacia, precisión y de manera más sostenible. Conceptos como digitalización, tecnologías de la información y la comunicación (TICs), internet de las cosas (IoT), análisis masivo...

Bioethanol production obtained from cereal straw has aroused great interest in recent years, which has led to the development of breeding programs to improve the quality of lignocellulosic material in terms of the biomass and sugar content. This process requires the analysis of genotype–phenotype relationships, and although genotyping tools are ver...

The perennial and stoloniferous weed, Cynodon dactylon (L.) Pers. (bermudagrass), is a serious problem in vineyards. The spectral similarity between bermudagrass and grapevines makes discrimination of the two species, based solely on spectral information from multi-band imaging sensor, unfeasible. However, that challenge can be overcome by use of 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...

This paper aims to evaluate the spatial persistence of wild oat patches in four wheat fields over time to determine the economic feasibility of using late-season wild oat maps for early site-specific weed management (SSWM) next season. The spatial persistence of wild oat patches was analyzed by three tests: land use change detection between years,...

The geometric features, such as canopy area, tree height and crown volume, of agricultural trees provide useful information to elucidate plantation status and to design input prescription maps adjusted to real crop needs. This work presents an innovative procedure for computing the 3-dimensional (3D) geometric features of almond trees by applying t...

Remote sensing technology allows monitoring the progress of vegetation and crop phenology in large regions. Seasonal vegetation trends are commonly estimated from high temporal resolution but coarse spatial resolution satellite imagery, e.g., from MODIS-NDVI (Moderate Resolution Imaging Spectroradiometer—Normalized Difference Vegetation Index) time...

Laurel wilt (Lw) disease is an exotic and lethal disease that can kill laurel family trees very fast. It is vectored by the redbay ambrosia beetle that prefers to live and lay eggs inside avocado trees (among other plants). Lw disease continues to expand in Florida posing a major threat to the avocado industry. Early and accurate disease detection...

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...

Revista Tierras - Agricultura

Efficiency in irrigation management is crucial to optimize water use in agriculture. A good irrigation strategy requires accurate and reliable measurements of crop water status that provide dynamic data and timely spatial information. However, this is not feasible with time-consuming manual measurements, which are also prone to cumulative errors du...

Precision viticulture has arisen in recent years as a new approach in grape production. It is based on assessing field spatial variability and implementing site-specific management strategies, which can require georeferenced information of the three dimensional (3D) grapevine canopy structure as one of the input data. The 3D structure of vineyard f...

Accurate and timely detection of weeds between and within crop rows in the early growth stage is considered one of the main challenges in site-specific weed management (SSWM). In this context, a robust and innovative automatic object-based image analysis (OBIA) algorithm was developed on Unmanned Aerial Vehicle (UAV) images to design early post-eme...

Several diseases have threatened tomato production in Florida, resulting in large losses, especially in fresh markets. In this study, a high-resolution portable spectral sensor was used to investigate the feasibility of detecting multi-diseased tomato leaves in different stages, including early or asymptomatic stages. One healthy leaf and three dis...

Se ha desarrollado una metodología automática para la detección temprana de malas hierbas dentro y fuera de la línea de cultivo en fase temprana usando como variable discriminante la altura de las plantas (cultivo y malas hierbas), calculada mediante técnicas fotogramétricas. Se utilizó un UAV equipado con una cámara modificada para captar informac...

Abstract Background Tree pruning is a costly practice with important implications for crop harvest and nutrition, pest and disease control, soil protection and irrigation strategies. Investigations on tree pruning usually involve tedious on-ground measurements of the primary tree crown dimensions, which also might generate inconsistent results due...

In Spain, the use of annual cover crops is a crop management practice for irrigated vineyards that allows controlling vineyard vigor and yield, which also leads to improve the crop quality. Recently, Cynodon dactylon (bermudagrass) has been reported to infest those cover crops and colonize the grapevine rows, resulting in significant yield and econ...

The availability of very high density cloud points is of increasing interest for scientists and other users involved in obtaining precise information for environmental, forestry or agronomical processes, among others. In the context of precision viticulture, UAV images are a potential way to map crop structure parameters, such as height row or vege...

Anthracnose crown rot (ACR) is one of the major diseases affecting strawberry crops grown in warm climates and causes huge yield losses each year. ACR is caused by the fungus Colletotrichum. Since this airborne disease spreads rapidly, detection at the early stage of infection is critical. The objective of this study was to investigate the feasibil...

El manejo adecuado de las cubiertas vegetales en viñedos permite equilibrar el vigor y rendimiento de la viña, resultando en una mejora de la calidad de la cosecha. Estas ventajas quedan mermadas con las infestaciones de grama (Cynodon dactylon), una mala hierba perenne difícilmente controlable. Por ello se analizaron imágenes obtenidas en viñedos...

Sorghum halepense (johnsongrass) is a perennial weed with a vegetative reproductive system and one of the most competitive weeds in maize showing a spatial distribution in compact patches. When maize is irrigated, successive weed emergences occur in the early phenological phases of the crop, which require several herbicide applications. Our aim was...

El manejo localizado de cultivos tiene como objetivo reducir la cantidad de insumos aplicados al campo, racionalizando los tratamientos según las necesidades reales derivadas de un análisis pormenorizado del cultivo. Este tipo de manejo implica un ahorro de costes para el agricultor e importantes beneficios medioambientales al reducirse el uso exce...

Laurel wilt (Lw) is a fatal disease. It is a vascular pathogen and is considered a major threat to the avocado industry in Florida. Many of the symptoms of Lw resemble those that are caused by other diseases or stress factors. In this study, the best wavelengths with which to discriminate plants affected by Lw from stress factors were determined an...

The multiple benefits of pruning in the olive trees are widely recognized, although not all techniques are equally favorable for all plantations and conditions. Thus, assessing pruning intensity (i.e., removed vegetation) and its effects on tree architecture (i.e., geometric features such as canopy area, tree height and crown volume) is essential t...

Site-specific weed management is defined as the application of customised control treatments only where weeds are located within the crop-field by using adequate herbicide according to weed emergence. The aim of the study was to generate georeferenced weed seedling infestation maps in two sunflower fields by analysing overlapping aerial images of t...

The Florida avocado industry is the state’s second-largest fruit industry (behind citrus) with 30,700 tons of avocado harvested in 2013 and a value of the production of $35 million at the wholesale level. Laurel wilt (LW) is a vascular disease that has recently spread rapidly along the southeastern seaboard of the United States. LW disease has the...

Laurel wilt (Lw) disease is a fatal disease caused by the fungus Raffaelea lauricola. It is a vascular pathogen which clogs the xylem, blocking the flow of water and nutrients in infected plants, and it is considered as a major threat to the commercial avocado production in Florida. Many of these symptoms are similar to those that are caused by oth...

Laurel wilt is a lethal disease of plants in the Lauraceae plant family, including avocado (Persea americana). This devastating disease has spread rapidly along the southeastern seaboard of the United States and has begun to affect commercial avocado production in Florida. The main objective of this study was to evaluate the potential to discrimina...

In order to optimize the application of herbicides in weed-crop systems, accurate and timely weed maps of the crop-field are required. In this context, this investigation quantified the efficacy and limitations of remote images collected with an unmanned aerial vehicle (UAV) for early detection of weed seedlings. The ability to discriminate weeds w...

Weed management is an important part of the investments in crop production. Cost of herbicides accounts for approximately 40% of the cost of all the chemicals applied to agricultural land in Europe. Although weeds are distributed in patches, herbicide treatments are usually broadcast over the entire field and there is potential for overapplication....

Site-specific weed management refers to the application of customised control treatments, mainly herbicide, only where weeds are located within the crop-field. In this context, the TOAS project is being developed under the financial support of the European Commission with the main objective of generating georeferenced weed infestation maps of certa...

A method to generate crop calendar and phenology-related maps at a parcel level of four major irrigated crops (rice, maize, sunflower and tomato) is shown. The method combines images from the ASTER and MODIS sensors in an object-based image analysis framework, as well as testing of three different fitting curves by using the TIMESAT software. Avera...

Obtaining weed patch maps for herbaceous crops in early season for site-specific weed control using remote sensing techniques has been a major challenge due to their spectral and appearance similarities. This is particularly problematic in the case of narrow row crops as wheat, where the weed discrimination has to be undertaken in a short time wind...

This investigation quantified the efficacy of visible and color-infrared images for weed mapping in a maize field by using remote images captured with an unmanned aerial vehicle at several flight altitudes (from 40 to 100 m). Results on weed discrimination were significantly affected by type of image and by type of weed (broad-leaved or grass weeds...

Laurel wilt is a lethal disease of avocado (Persea americana) caused by the fungus Raffaelea lauricola and vectored by ambrosia beetles. This devastating disease has the potential to destroy avocado production in Florida. The objective of this investigation was to evaluate the potential to discriminate laurel wilt-infested trees from healthy trees...

Mapping vegetation in crop fields is an important step in remote sensing applications for precision agriculture. Traditional aerial platforms such as planes and satellites are not suitable for these applications due to their low spatial and temporal resolutions. In this article, a UAV equipped with a commercial camera (visible spectrum) was used fo...

A procedure to achieve the semi-automatic relative image normalization of multitemporal remote images of an agricultural scene called ARIN was developed using the following procedures: 1) defining the same parcel of selected vegetative pseudo-invariant features (VPIFs) in each multitemporal image; 2) extracting data concerning the VPIF spectral ban...

La detección de malas hierbas en fase temprana requiere imágenes de muy elevada resolución espacial (píxeles < 5cm). Actualmente, sólo los vehículos aéreos no tripulados (UAV) pueden generar este tipo de imágenes. El objetivo de este trabajo fue la puesta a punto de un UAV con el fin de obtener imágenes de alta resolución espacial que permita una p...

Se presenta una innovación tecnológica consistente en la adquisición de imágenes multiespectrales de muy alta resolución espacial con un vehículo aéreo no tripulado (UAV) y el análisis automático de dichas imágenes mediante técnicas basadas en objetos, con el objetivo de detectar malas hierbas y cuantificar su porcentaje de infestación en una parce...

The use of remote imagery captured by unmanned aerial vehicles (UAV) has tremendous potential for designing detailed site-specific weed control treatments in early post-emergence, which have not possible previously with conventional airborne or satellite images. A robust and entirely automatic object-based image analysis (OBIA) procedure was develo...

A new aerial platform has become available in recent years for image acquisition, the Unmanned Aerial Vehicle (UAV). This article defines and evaluates the technical specifications of an UAV and the spatial and spectral properties of the images captured by two different sensors, a still visible camera and a six-band multispectral camera, for early...

This article explores the potential use of multi-spectral high-spatial resolution QuickBird imagery to detect cruciferous weed patches in winter wheat fields. In the present study, research was conducted on six individual naturally infested fields (field-scale study: field area ranging between 3 and 52 ha) and on a QuickBird-segmented winter wheat...

A new aerial platform has risen recently for image acquisition, the Unmanned Aerial Vehicle (UAV). This article describes the technical specifications and configuration of a UAV used to capture remote images for early season site- specific weed management (ESSWM). Image spatial and spectral properties required for weed seedling discrimination were...

High spatial resolution images taken by unmanned aerial vehicles (UAVs) have been shown to have the potential for monitoring agronomic and environmental variables. However, it is necessary to capture a large number of overlapped images that must be mosaicked together to produce a single and accurate ortho-image (also called an orthomosaicked image)...

In the context of weed detection in crop-fields for site-specific weed control, the first step is to identify and count crop rows for a further successful discrimination of weeds. In this work, an accurate object-based image analysis (OBIA) methodology based on a looping procedure has been developed for the classification of crop rows in a maize fi...