Montserrat Jurado-Expósito

Spanish National Research Council | CSIC · Institute for Sustainable Agriculture (IAS)

Assessing the spatial distribution of weeds within a field is a key step to the success of site-specific weed management strategies. Centaurea diluta (knapweed) is an emerging weed that is causing a major agronomic problem in southern and central Spain because of its large size, the difficulty of controlling it, and its high competitive ability. Th...

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...

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,...

This paper compares of pixel- and object-based techniques for mapping wild oat weed patches in wheatfields using multi-spectral QuickBird satellite imagery for site-specific weed management. The researchwas conducted at two levels: (1) at the field level, on 11 and 15 individual infested wheat fields in 2006 and2008, respectively, and (2) on a broa...

A method was developed to normalize multitemporal remote images based in vegetative pseudo-invariant features (VPIFs), as following: 1) defining the same parcel for each selected VPIF in each multitemporal image; 2) extracting the VIPF spectral bands data for each image; 3) calculating the correction factor (CF) for each image band to fit it to the...

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...

Georeferencing of remote imagery with high spatial resolution can be achieved using the semiAUtomatic GEOreferencing (AUGEO) system which is based on artificial terrestrial targets (ATTs) and software AUGEO-2.0 for location and georeferencing. The aim of this letter is to describe the system and validate it. The ATTs consist of colored hexagonal ta...

Cruciferous weeds are competitive broad-leaved species that cause losses in winter crops. In the present study, research on remote sensing was conducted on seven naturally infested fields located in Córdoba and Seville, southern Spain. Multi-spectral aerial images (four bands, including blue (B), green (G), red (R) and near-infrared bands) taken in...

Avena sterilis weed pressure categories can be discriminated in wheat through remote images taken at late stages of wheat senescence. Site-specific image processing was achieved with SARI ® , an add-on software program for ENVI ® developed to implement precision agriculture. Using the SARI software and crop-weed competition and economic models, the...

In the context of detection of weeds in crops for site-specific weed control, on-ground spectral reflectance measurements are the first step to determine the potential of remote spectral data to classify weeds and crops. Field studies were conducted for four years at different locations in Spain. We aimed to distinguish cruciferous weeds in wheat a...

Software was developed to spatially assess key crop characteristics from remotely sensed imagery. Sectioning and Assessment of Remote Images (SARI®), written in IDL® works as an add-on to ENVI®, has been developed to implement precision agriculture strategies. SARI® splits field plot images into grids of rectangular “micro-images” or “micro-plots”....

One important issue in agriculture is related to the automatization of tasks for reducing control measurements. Optical sensors provide images that must be conveniently processed. The most relevant image processing procedures require the identification of textures belonging to crops and weeds, so that some types of strategies must be carried out, i...

In precision agriculture, especially in weed control, it is essential to have accurate information about the weed distribution, i.e. a weed map. So a crucial task is the generation of accurate weed maps. This paper proposes a new automatic approach for identification of agricultural textures (crop and weed) in remote images using a non -...

The aim of this paper is to assess co-registration errors in remote imagery through the AUGEO system, which consists of geo-referenced coloured tarps acting as terrestrial targets (TT), captured in the imagery and semi-automatically recognised by AUGEO2.0® software. This works as an add-on of ENVI® for image co-registration. To validate AUGEO, TT w...

Cruciferous weeds are very competitive broadleaf species and frequently infest cereal and legume crops. These weeds seriously impair crop development and cause high yield losses. Herbicides are commonly applied over an entire agricultural field although weeds are spatially distributed in patches. To reduce the herbicide use by applying them only wh...

Olive (Olea europaea L.) is the main perennial Spanish crop. Soil management in olive orchards is mainly based on intensive and tillage operations, which have a great relevancy in terms of negative environmental impacts. Due to this reason, the European Union (EU) only subsidizes cropping systems which require the implementation of conservation agr...

In Spain, water for agricultural use represents about 85% of the total water demand, and irrigated crop production constitutes a major contribution to the country's economy. Field studies were conducted to evaluate the potential of multispectral reflectance and seven vegetation indices in the visible and near-infrared spectral range for discriminat...

Wheat, Triticum durum L, is a major cereal crop in Spain with over five million ha grown annually. Wild oat, Avena sterilis L., and canary grass, Phalaris spp., are distributed only in patches in wheat fields but herbicides are applied over entire fields, thus leading to overapplication and unnecessary pollution. To reduce herbicide application, si...

Isoproturon, propyzamide and alachlor were incubated in a sandy clay loam soil either with constant conditions (10°C or 20°C with soil moisture at 10% or 20% by weigh) or with variable temperature at constant soil moisture, variable soil moisture at constant temperature, or with both temperature and soil moisture varying over time. Rates of degrada...

Rates of degradation of isoproturon, diuron and metsulfuron-methyl were measured in two soils incubated at two temperatures (5 and 25 °C) with soil moisture at a matric potential of −5 kPa. Rates of change in soil solution concentration were also measured after extraction of water from the soil using a centrifugation technique. The data, in general...

This study investigated the relationships between sunflower yield and crop multi-temporal spectral data obtained from aerial photographs, land elevation and the presence of Ridolfia segetum weed. Conventional-color and color-infrared airborne photographs were taken at three dates corresponding to the vegetative, flowering and senescent crop stages....

Logistic Regression (LR) has become a widely used and accepted method to analyze binary or multiclass outcome variables, since it is a flexible tool that can predict the probability for the state of a dichotomous variable. A recently proposed LR method is based on the hybridization of a linear model and Evolutionary Product-Unit Neural Network (EPU...

Currently, monitoring of agrarian policy actions usually requires ground visits to sample targeted farms, a time-consuming and very expensive procedure. To improve this, we have undertaken a study of the accuracy of five supervised classification methods (Parallelepiped, Minimum Distance, Mahalanobis Classifier Distance, Spectral Angle Mapper and M...

Field and laboratory studies were conducted from 1993 to 1997 to determine the feasibility of controlling nodding broomrape in sunflower by treating crop seeds with pronamide. Soaking sunflower seeds for 5 min in 50% pronamide solution or coating at the equivalent of 2 kg/ha with pronamide did not impair seed germination or seedling growth, and con...

A major concern in landscape management and precision agriculture is the variable-rate application of herbicides in order to reduce herbicide treatment load. These applications require a correct assessment and knowledge of the density and potential spatial variability of weed species within fields. This article addresses the issue of incorporating...

Geostatistical techniques were used to describe and map weed spatial distribution in two sunflower fields in Cabello and Monclova, southern Spain. Data from the study were used to design intermittent spraying strategies. Weed species, overall infestation severity (IS) index, and spatial distribution varied considerably between the two sites. Weed s...

Soil management in crops is mainly based on intensive tillage operations, which have a great relevancy in terms of increase of atmospheric CO2, desertification, erosion and land degradation. Due to these negative environmental impacts, the European Union only subsidizes cropping systems which require the implementation of certain no-tillage systems...

(EN)The invention relates to a method for automatically splitting/dividing remote images into smaller rectangular images (micro-images/micro-parcels) and obtaining agronomic and environmental indicators in each image and in the entire parcel. The invention is based on processing high-spatial-resolution remote images using the SARI® computer program...

Remote sensing (RS), geographic information systems (GIS), and global positioning systems (GPS) may provide the technologies needed for farmers to maximize the economic and environmental benefits of precision farming. Site-specific weed management (SSWM) is able to minimize the impact of herbicide on environmental quality and arises the necessity o...

Logistic regression (LR) has become a widely used and accepted method to analyse binary or multiclass outcome variables, since it is a flexible tool that can predict the probability for the state of a dichotomous variable. A recently proposed LR method is based on the hybridisation of a linear model and evolutionary product-unit neural network (EPU...

The agrarian policy of the European Union tends to support sustainable agriculture, subsidising only cropping systems that are implemented with specific agro-environmental measures. These actions require a precise follow-up of the crops and of the agricultural practices over a large surface. To that end, remote-sensing techniques are unique and cos...

Key agronomic and environmental characteristics of tree orchards can be automatically assessed from remote sensing images by a computer program named Clustering Assessment® (CLUAS). The aim of this paper is to describe the CLUAS software development and the information generated by CLUAS for selected olive orchards and its validation with ground-tr...

Recent advances in remote sensing technology have triggered the need for highly flexible modelling methods to estimate several crop parameters in precision farming. The aim of this work was to determine the potential of evolutionary product unit neural networks (EPUNNs) for mapping in-season yield and forecasting systems of sunflower crop in a natu...

Field studies were conducted to determine the potential of multispectral classification of late-season grass weeds in wheat. Several classification techniques have been used to discriminate differences in reflectance between wheat and Avena sterilis, Phalaris brachystachys, Lolium rigidum and Polypogon monspeliensis in the 4002013900�nm spectrum, a...

(EN)This method quantitatively characterises tree plantations using high resolution spatial remote detection and processing of the related images, wherein information is provided on each tree and on the plantation as a whole. Thus, the method provides individualised information including the geographical baricentric coordinates, surface and potenti...

Hyperspectral reflectance curves of olive (Olea europaea L.) trees under different N or K treatments, and the best wavelengths or vegetation indices to discriminate between different N or K applications using discriminant analysis were investigated. Field hyperspectral studies were carried out in two olive orchards located at Cabra and Lucena (sout...

Ridolfia segetum is a frequent umbelliferous weed in sunflower crops in the Mediterranean basin. Field and remote sensing research was conducted in 2003 and 2004 over two naturally infested fields to determine the potential of multispectral imagery for discrimination and mapping of R. segetum patches in sunflower crops. The efficiency of the four w...

Sunflower is an important crop which is frequently infested by the umbeliferous weed Ridolfia segetum in the Mediterranean area. The objective of this study was to establish preliminary information on the relationship between crop yield, weed infestation and remote-sensed imagery. The study was conducted on a 42 ha farm named Matabueyes located in...

This article describes an application of nonparametric regression to study the spatial structure and identify persistent spatial patterns of the perennial weed Convolvulus arvensis L. in 4 years of wheat-sunflower crop rotation in Southern Spain. The annual spatial distributions of weed patches over the study field are estimated using local linear...

Field research was conducted to determine the potential of hyperspectral and multispectral imagery for late-season discrimination and mapping of grass weed infestations in wheat. Differences in reflectance between weed-free wheat and wild oat, canarygrass, and ryegrass were statistically significant in most 25-nm-wide wavebands in the 400- and 900-...

Field research was conducted to determine the potential of hyperspectral and multispectral imagery for late-season discrimination and mapping of grass weed infestations in wheat. Differences in reflectance between weed-free wheat and wild oat, canarygrass, and ryegrass were statistically significant in most 25-nm-wide wavebands in the 400- and 900-...

Ridolfia segetum is an umbelliferous weed frequent and abundant in sunflower crops in the Mediterranean basin. Field research was conducted to evaluate the potential of hyperspectral and multispectral reflectance and five vegetation indices in the visible to near infrared spectral range, for discriminating bare soil, sunflower and R. segetum at dif...

(EN)The invention relates to a method of differentiating and quantifying an olive grove with vegetative covers by means of remote sensing with high-resolution space sensors. The invention is suitable for use in agriculture and, more specifically, by enterprises providing technical assistance in the field of agriculture or the environment or in rela...

This paper attempts to compare various prediction methods for mapping soil properties (texture, organic matter (OM), pH, phosphorus and potassium) for precision farming approaches by incorporating secondary spatial information into the mapping. The primary information (or primary attribute) was obtained from an intensive grid soil sampling and the...

Convolvulus arvensis L. is an important perennial weed that infests wheat (Triticum aestivum L.) and sunflower (Helianthus annuus L.) in Spain. Many fields of this rotation have been converted to no-tillage or reduced tillage, so perennial weeds such as C. arvensis have become more troublesome since they cannot be reduced in abundance by repeated t...

Ridolfia segetum Moris is an umbelliferous weed, which is very frequent and persistent in most sunflower crops in Spain. The hyperspectral signatures of bare soil and sunflower and Ridolfia segetum at different phenological stages (from emergency to senescence) were collected at three dates (mid-May, mid-June and mid-July 2003) using a handheld fie...

This research addresses the issue of incorporating a digital elevation model (DEM) as secondary spatial information into the mapping of dominant weed species present in two sunflower crops in Andalusia (Spain). Two prediction methods were used and compared for mapping weed density for precision agriculture approaches: ordinary point kriging (OK), a...

(EN)The invention relates to a method of differentiating uses of soil and quantifying vegetative cover by means of remote sensing with aerial photography. The invention is suitable for use in agriculture and, more specifically, by enterprises providing technical assistance in the field of agriculture or the environment or in relation to public or p...

Intensive field surveys of Convolvulus arvensis were conducted over the course of four growing seasons (1999–2002) in a 1.6 ha section of a field located in Andalusia, southern Spain, cropped with wheat in 1999 and 2001 and with sunflower in 2000 and 2002. In order to characterise the spatial and temporal variability of C. arvensis density, geostat...

Spatial variability of leaf nutrients (N, P, K, B and Fe) in a 30 ha olive orchard located in southern Spain was examined in two consecutive years for determining their spatial distribution for the implementation of a site-specific fertilization programme. A regular 75 m×75 m sampling grid was established and intersection points (nodes) were georef...

This work aims to determine variations in cover crop, bare soil and tree areas in olive (Olea europaea L.) groves as affected by the season based on aerial photographs and estimated vegetation indexes. Conventional-colour and colour-infrared aerial photographs were taken in spring and summer on three olive farms of 75-100 ha, from a plane at 1525 m...

Intensive field surveys of Convolvulus arvensis were conducted over the course of four growing seasons (1999–2002) in a 1.6 ha section of a field located in Andalusia, southern Spain, cropped with wheat in 1999 and 2001 and with sunflower in 2000 and 2002. In order to characterise the spatial and temporal variability of C. arvensis density, geostat...

The potential of using near-infrared reflectance spectroscopy (NIRS) to discriminate between seven broadleaf weed species, sunflower and wheat stubble was evaluated. Our results showed that the spectral window between 750 and 950nm, which corresponds to near-infrared wavelength, was able to discriminate among wheat stubble, sunflower and the most p...

Spatial patterns for seven soil chemical properties and textures were examined in two fields in southern Spain (Monclova and Caracol, province of Seville, Andalusia) in order to identify their spatial distribution for the implementation of a site-specific fertilization practice. Two sampling grids of 3520 and 3535 m were established in Caracol and...

Thirty samples of soil were taken at 50-m intersections on a grid pattern over an area of 250 x 200 m within a single field with nominally uniform soil characteristics. Incubations of isoproturon (3-(4-isopropylphenyl)-1,1-dimethylurea) under standard conditions (15 degrees C; -33 kPa soil water potential) indicated considerable variation in degrad...

[14C]-Imazethapyr was applied as a seed treatment and at plant pre-emergence and post-emergence to peas (Pisum sativum L.) parasitized by Orobanche crenata Forsk. Herbicide uptake increased with time regardless of the application method. Uptake reached about 98%, 89%, 81% and 94% of the total herbicide applied for the seed coating, seed soaking, pr...

Studies were conducted from 1993 to 1995 in Southern Spain to determine the feasibility of controlling broomrape (Orobanchecrenata Forsk.) in broad bean (Viciafaba L.) and lentil (Lensculinaris L.) by treating seeds with imazethapyr and imazapyr. In the broad bean, soaking for 5 min in 0·0140 g ha1) with imazethapyr (Pursuit-10) did not affect seed...

Studies were conducted from 1993 through 1995 to determine broomrape control from imazethapyr applied to pea seeds. Soaking seeds for 1 to 10 min in 0.0001% to 1% imazethapyr (Pursuit-10) solutions or coating seeds with imazethapyr at 0.025 to 0.30 mg/g (herbicide/seed, equivalent to 5 to 60 g/ha for a seeding rate of 200 kg/ha) did not affect seed...

Field studies were conducted at nine locations in southern Spain during 2 yr to develop models of nodding broomrape competition with sunflower and to establish economic thresholds. At each location, 30 to 35 small plots, each consisting of three sunflower plants, were chosen at random. The infection severity (BIS, no. of emerged broomrapes per sunf...

Referencia OEPM: P9402152.-- Fecha de solicitud: 14/10/1994.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC). Peer reviewed

Field studies were conducted from 1991 through 1994 in several locations of Southern Spain to determine the efficacy of imazapyr as late postemergence application in sunflower for broomrape control and the crop response to this herbicide under weed-free conditions. Single applications of imazapyr at 10 to 15 g/ha on sunflower plants at about the V1...

Satellite and airborne remote sensed images cover large areas, which normally include dozens of agricultural plots. Agricultural operations such as sowing, fertilization, and pesticide applications are designed for the whole plot area, i.e. 10 to 30 ha, or through precision agriculture. This takes into account the spatial variability of biotic and...

The software SARI® has been developed to implement precision agriculture strategies through remote sensing imagery. It is written in IDL® and works as an add-on of ENVI®. It has been designed to divide remotely sensed imagery into "micro-images", each corresponding to a small area ("micro-plot"), and to determine the quantitative agronomic and/or e...

RESUMEN La clasificación de los diferentes cultivos de regadío según su desarrollo fenológico con técnicas de Teledetección es importante para estimar el área que ocupan, sus requerimientos hídricos, y realizar un seguimiento exhaustivo de las prácticas de regadío en grandes superficies de terrero. En el Valle del Guadalquivir, dichos cultivos pres...

RESUMEN En prospecciones de campo se constató que las malas hierbas crucíferas infestan los cultivos de invierno produciendo elevadas pérdidas en producción. Este trabajo consistió en la clasificación supervisada de rodales de crucíferas en cultivos de trigo, habas y guisantes utilizando imágenes aéreas y técnicas de teledetección para su aplicació...

Referencia OEPM: P200401438.-- Fecha de solicitud: 11/06/2004.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC). El presente procedimiento tiene aplicación en Agricultura, y más concretamente en Empresas de Asistencia Técnica Agraria o Medioambiental o bien en Auditorias Agroambientales Públicas o Privadas. Principalmente consiste...

Referencia OEPM: P9402328.-- Fecha de solicitud: 11/11/1994.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC). El procedimiento consiste en aplicar el herbicida en postemergencia del cultivo, mediante un aplicador convencional de herbicida, en unas fases definidas del ciclo de desarrollo del cultivo y a unas dosis de herbicida por...

Referencia OEPM: P9802354.-- Fecha de solicitud: 11/11/1998.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC). El objeto del presente certificado de adición es una mejora introducida en la patente nº 9402328, de título "Procedimiento de utilización selectiva del herbicida imazapir en el cultivo de girasol para el control de la male...

Referencia OEPM: P9402150.-- Fecha de solicitud: 14/10/1994.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC). Peer reviewed

Referencia OEPM: P9402149.-- Fecha de solicitud: 14/10/1994.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC). Peer reviewed

Referencia OEPM: P9402151.-- Fecha de solicitud: 14/10/1994.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC). Peer reviewed