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Alberto Tellaeche Xavier P. BurgosArtizzu Gonzalo Pajares Angela Ribeiro Csar Fernndez-Quintanilla 《Computers and Electronics in Agriculture》2008,60(2):144-155
One of the objectives of precision agriculture is to minimize the volume of herbicides by using site-specific weed management systems. To reach this goal, two major factors need to be considered: (1) the similarity of spectral signatures, shapes, and textures between weeds and crops and (2) irregular distribution of weeds within the crop. This paper outlines an automatic computer vision method for detecting Avena sterilis, a noxious weed growing in cereal crops, and differential spraying to control the weed. The proposed method determines the quantity and distribution of weeds in the crop fields and applies a decision-making strategy for selective spraying, which forms the main focus of the paper. The method consists of two stages: image segmentation and decision-making. The image segmentation process extracts cells from the image as the low-level units. The quantity and distribution of weeds in the cell are mapped as area and structural based attributes, respectively. From these attributes, a multicriteria decision-making approach under a fuzzy context allows us to decide whether any given cell needs to be sprayed. The method was compared with other existing strategies. 相似文献
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164.
Jaime Puértolas Marta Pardos María Dolores Jiménez Ismael Aranda José Alberto Pardos 《Annals of Forest Science》2008,65(6):611-611
165.
Julio C. Barbosa Sarah S. Barreto Alice K. Inoue-Nagata Marcelo S. Reis Ana Carolina Firmino Armando Bergamin Filho Jorge Alberto Marques Rezende 《Journal of General Plant Pathology》2009,75(6):440-443
Nicandra physaloides, a common weed in South America, was found to be infected by an isolate of Tomato severe rugose virus (ToSRV), a bipartite begomovirus. The plants developed severe yellow rugose mosaic and were collected in São Paulo State, Brazil. This isolate of ToSRV was transmitted by Bemisia tabaci B biotype from infected plants of N. physaloides to healthy plants of N. physaloides and tomato in a glasshouse. This is the first report of natural infection of N. physaloides by ToSRV in Brazil. 相似文献
166.
Alberto Falco Mikolaj Adamek Patricia Pereiro David Hoole Jos Antonio Encinar Beatriz Novoa Ricardo Mallavia 《Marine drugs》2022,20(6)
The high proliferation of microorganisms in aquatic environments has allowed their coevolution for billions of years with other living beings that also inhabit these niches. Among the different existing types of interaction, the eternal competition for supremacy between the susceptible species and their pathogens has selected, as part of the effector division of the immune system of the former ones, a vast and varied arsenal of efficient antimicrobial molecules, which is highly amplified by the broad biodiversity radiated, above any others, at the marine habitats. At present, the great recent scientific and technological advances already allow the massive discovery and exploitation of these defense compounds for therapeutic purposes against infectious diseases of our interest. Among them, antimicrobial peptides and antimicrobial metabolites stand out because of the wide dimensions of their structural diversities, mechanisms of action, and target pathogen ranges. This revision work contextualizes the research in this field and serves as a presentation and scope identification of the Special Issue from Marine Drugs journal “The Immune System of Marine Organisms as Source for Drugs against Infectious Diseases”. 相似文献
167.
Since its detection in the Mediterranean basin at the end of 2006 and later in other European countries, the South American tomato pinworm, Tuta absoluta (Meyrick), has become a serious threat to tomato crops. In newly infested areas, it is especially problematic during the first years of its presence. Nevertheless, after 2–3 years, the incidence of T. absoluta has become less severe in certain areas. There are several factors contributing to this decline, such as the increase in growers' knowledge of pest behaviour and biology and the correct application of integrated pest control strategies. The impact of opportunistic native natural enemies (fortuitous biological control) should be considered as one of the key factors in this decline. In this review, available information on indigenous natural enemies is updated, and the current pest management approaches used against T. absoluta are addressed. Finally, future scenarios for biological control of this pest are discussed. Copyright © 2012 Society of Chemical Industry 相似文献
168.
Alberto Mosca Zohil DVM M. Cecilia Castellano DVM 《Veterinary radiology & ultrasound》1995,36(5):393-396
A comparative study was conducted in ten dogs with signs of prostatic disease in order to evaluate the usefulness of the prepubic and transrectal ultrasonography for the examination of the prostate gland and for prostate biopsy guidance. Both techniques were adequate to identify the prostate gland and prostatic urethra. Transrectal ultrasound found 5 occurrencies of parenchymal echogenicity changes whereas the prepubic technique found only 2. Lesions in the cranial prostatic margin (two dogs) were detected only by prepubic ultrasound. Lesions of the caudal prostatic margin (six dogs), prostatic urethra disruption (two dogs) and prostatic capsule abnormalities (five dogs) were only recognized by the transrectal approach. Prepubic ultrasonography was useful for biopsy guidance of cranial prostatic lesions and transrectal ultrasonography was a good means for biopsy guidance of caudal lesions. 相似文献
169.
170.
de Almeida Daniel Mageste Marcondes Marcos Inácio Rennó Luciana Navajas Pereira Silva Luiz Henrique Martins Leandro Soares Marquez David Esteban Contreras Castaño Villadiego Faider Alberto Velez Saldarriaga Felipe Franco Julian David Castaño Moreno Deilen Paff Sotelo de Moura Felipe Henrique Paulino Mário Fonseca 《Tropical animal health and production》2019,51(1):79-87
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of strategic supplementation in the dry period and dry/rainy transition period on the performance and... 相似文献