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Journal of Pest Science - Conservation biological control involves manipulation of the environment to enhance the effectiveness of natural enemies in controlling crop pests. In this study, we...  相似文献   
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Media monitoring for emerging risks has become an essential tool in public health. This approach also has the potential to deliver early warning of emerging risks to plant health. The European Food Safety Authority (EFSA) has launched a project in collaboration with the Joint Research Centre (JRC) of the European Commission to make use of the Medical Information System (MedISys) media monitoring tool for monitoring plant health threats. This paper provides a summary of the project, which is taking place in partnership with the University of Lleida and the Institut de Recerca I Tecnologia Agroalimentàries. The four specific objectives of the project are: (1) to collate new and appropriate media and information sources, (2) to develop a multilingual ontology for the global identification of emerging new plant health threats, (3) to develop strategies to monitor (re‐)emerging plant health threats at global and regional scales, and (4) to test approaches for reporting the identified warnings to the relevant EFSA units and experts through the MedISys interface, including mapping and georeferencing. The plan and structure of the project are presented with examples of preliminary results.  相似文献   
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We assess the effects of changing land use and crop management on alfalfa insect abundance by comparing it in 50 alfalfa fields when they were inserted in landscapes with different proportions of arable crops and orchards. Land use in a buffer of 500 m was assessed, and alfalfa insect abundance was estimated with sticky yellow traps. The number of catches of several herbivores and predators was related to the proportion of landscape components and several field variables. Results indicated that the proportion of orchards in the buffer negatively affected the abundance of predators on alfalfa, likely because orchards treated with pesticides are a sink for predators moving in the landscape, among other possible causes. Other landscape variables such as noncrop habitats, winter cereals, and landscape diversity analysed by the Shannon index had a minor influence. Among field variables, field size influenced positively the abundance of insects on alfalfa, whereas alfalfa growth stage and age affected positively or negatively the different herbivores and predators. Of course, abundance of predators and prey was affected by the abundance of prey and predators, respectively. These findings suggest that a high proportion of intensively managed crops (orchards) in the landscape interferes with the role of alfalfa as a reservoir of predatory insects for adjacent crops and that the responses to local and landscape structures are temporal and species-specific as previously concluded for maize. Consequently, landscape and field management strategies to improve pest control must consider both types of variables as well as their changing influence when we modify them.

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Near infrared reflectance spectroscopy (NIRS) was used to predict the nutritional value of dog foods sold in Chile. Fifty-nine dry foods for adult and growing dogs were collected, ground and scanned across the visible/NIR range and subsequently analysed for dry matter (DM), crude protein (CP), crude fibre (CF), total fat, linoleic acid, gross energy (GE), estimated metabolizable energy (ME) and several amino acids and minerals. Calibration equations were developed by modified partial least squares regression, and tested by cross-validation. Standard error of cross validation (SE(CV)) and coefficient of determination of cross validation (SE(CV)) were used to select best equations. Equations with good predicting accuracy were obtained for DM, CF, CP, GE and fat. Corresponding values for and SE(CV) were 0.96 and 1.7 g/kg, 0.91 and 3.1 g/kg, 0.99 and 5.0 g/kg, 0.93 and 0.26 MJ/kg, 0.89 and 12.4 g/kg. Several amino acids were also well predicted, such as arginine, leucine, isoleucine, phenylalanine-tyrosine (combined), threonine and valine, with values for and SE(CV) (g/kg) of 0.89 and 0.9, 0.94 and 1.3, 0.91 and 0.5, 0.95 and 0.9, 0.91 and 0.5, 0.93 and 0.5. Intermediate values, appropriate for ranking purposes, were obtained for ME, histidine, lysine and methionine-cysteine. Tryptophan, minerals or linoleic acid were not acceptably predicted, irrespective of the mathematical treatment applied. It is concluded that NIR can be successfully used to predict important nutritional characteristics of commercial dog foods.  相似文献   
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