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1.
Market-oriented production of gardening crops and cassava (Manihot utilissima) in the dry season is an increasingly frequent practice in Ségou, Mali. Traditionally, these crops are protected from roaming livestock with the help of dead fences. In order to provide a sustainable alternative to dead fences, the International Centre for Research in Agroforestry (ICRAF) began promoting the use of live fences, living trees planted closely together around a field plot. This study was conducted with the first farmers to use these live fences. These farmers expressed satisfaction with the protection offered by the trees and their ability to provide a variety of medicinal, economic, and food products. The form of land tenure, the social status of farmers within their families, and the availability of labour seem to be important factors in the decision to test the live fence. This raises questions about the accessibility of this technique and its possible contribution to the social and economic differentiation of its users. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
2.
Pasteuria penetrans, a bacterial parasite of plant-parasitic nematodes, is used to control root-knot nematode Meloidogyne spp. populations in vegetable crops. But its efficiency is variable, mostly because of the patchy distribution of the bacteria in arable fields. As the infective P. penetrans are non-motile bacteria in soil, abiotic soil factors can affect the bacteria–nematode relationships. An epidemiological study, conducted in a vegetable field, showed that abiotic factors such as irrigation, soil water holding capacity and texture, affected the efficiency of P. penetrans. A correspondence analysis between these abiotic factors and the density of P. penetrans spores in the soil, and the proportion of Meloidogyne javanica juveniles infected by the bacteria, revealed that irrigation affected directly the distribution of the spores in soil pores related to their passive transport by water flow. Laboratory experiments conducted on the passive transport of spores confirmed that intensive irrigation leached the spores down the soil profile and decreased the percentage of infected Meloidogyne juveniles.  相似文献   
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Irrigation plays a fundamental role in world food provision but, to date, it has performed below expectations in Sub-Saharan Africa. The present study assesses and diagnoses the performance of 22 small and medium size community-managed irrigation schemes, mainly devoted to rice production, in different locations along the Mauritanian banks of the Lower Senegal River. The evaluations followed the Rapid Appraisal Process in which semi-structured interviews were held with representatives of the Cooperatives’ Boards in charge of each scheme to obtain information about the organisation of the cooperative, land tenure, irrigation system and organization, cropping pattern and soils. Additionally, for each irrigation scheme, the water-delivery service was characterized by making qualitative and comparative observations during field inspections; the pumping station's performance was diagnosed by a local specialist; the discharge at the head of the system was measured; daily irrigation time was recorded; and crop yields were determined by plot sampling. Then a set of performance indicators was computed. Water delivery capacity referred to irrigated areas was insufficient in a third of the schemes, and this insufficiency was exacerbated by poor maintenance. Irrigation intensity in habilitated areas was rather low being less than 0.66 in 50% of the schemes. The average productivity of land, irrigation water, and fuel (3.38 t ha−1, 0.30 kg m−3 and 2.37 kg kWh−1, respectively) were well below potential.  相似文献   
5.
The screening of 50 sorghum varieties showed that, on average, germination did not affect the content in total phenolic compounds but decreased the content of proanthocyanidins, 3-deoxyanthocyanidins, and flavan-4-ols. Independent of germination, there are intervarietal differences in antioxidant activities among sorghum varieties. Phenolic compounds and antioxidant activities were more positively correlated in ungerminated varieties than in germinated ones. Sorghum grains with pigmented testa layer, chestnut color glumes, and red plants had higher contents, larger diversity of phenolic compounds, and higher antioxidant activities than other sorghums. Some red sorghum varieties had higher antioxidant activities (30-80 mumol of Trolox equiv/g) than several sources of natural antioxidants from plant foods. Among varieties used for "to", "dolo", couscous, and porridge preparation, the "dolo"(local beer) varieties had the highest average content and diversity in phenolic compounds as well as the highest antioxidant activities. The biochemical markers determined are useful indicators for the selection of sorghum varieties for food and agronomic properties.  相似文献   
6.
Analysis of fifty sorghum [Sorghum bicolor (L.) Moench] varieties used in Burkina Faso showed that they have different contents of phenolic compounds, peroxidase (POX), and polyphenol oxidase (PPO). Most of the varieties (82%) had a tannin content less than 0.25% (w/w). POX specific activity was higher than the monophenolase and o-diphenolase specific activities of PPO. For POX, there was a diversity of isoforms among varieties. No clear correlation could be made between the quantitative composition of the grain in phenolics, PPO, and POX, and resistance of plant to pathogens. In general, varieties good for a thick porridge preparation ("t?") had low phenolic compounds content and a medium POX activity. From the red varieties, those used for local beer ("dolo") had a high content in phenolic compounds and PPO, and a low POX activity. The variety considered good for couscous had a low POX content. The characteristics might be useful as selection markers for breeding for specific applications.  相似文献   
7.
Summary A survey of small-scale poultry production in an urban and two agro-pastoral systems covered 381 households. Less detailed information was also obtained from a small sample in a transhumant pastoral system. More households owned poultry in the rice (89·5%) than in the millet (81·1%) or urban (57·1%) systems. Domestic fowl were commonest in all systems followed by pigeons, Guinea fowl and then ducks, although the last were absent from the millet zone. Most families kept only one species but there was more diversification in the rice system. Flock sizes were largest in the rice system for fowls, Guinea fowl and pigeons while duck flocks averaged more birds in the urban area. Females predominated in all species except pigeons where sex ratios were about equal. Management practices in relation to housing, feeding, health care and consumption and marketing are described. Productivity figures relating to egg production, egg size, hatchability, growth and mortality are provided.
Resumen Se efectuó una inspección a corta escala, de la producción de aves en un sistema urbano y dos rurales, cubriendo 381 explotaciones. Se obtuvo tambien información no muy detallada, de una muestra peque?a en un sistema pastoral transhumante. La mayoría de empresarios se encontraron en los niveles productores de arroz (89,5%), que en los de millo (81,1%) o urbanos (57,1%). La crianza de gallinas y pollos domésticos predominó sobre la de palomos, gallinetas y patos. Estos últimos no se encontraron entre los cultivadores de millo. La mayoría de familias criaba una sola especie, pero hubo más diversificación entre los cultivadores de arroz. El tama?o de las parvadas fue mayor entre los cultivadores de arroz, en lo relacionado con gallinas, gallinetas y palomos, mientras que las parvadas de patos fueron más numerosas en áreas urbanas. Las hembras predominaron en todas las especies, con la excepción de los palomos, en donde los sexos fueron iguales. Se describen las prácticas de manejo y comercialización. Tambien se dan datos de productividad en cuanto a producción de huevos, tama?o de los mismos, eclosión y mortalidad.

Résumé Une étude de la production avicole à petite échelle dans un système urbain et dans deux systèmes agro-pastoraux a couvert 381 foyers. On a obtenu moins d’informations détaillées dans un petit échantillon d’un système pastoral transhumant. Il y a plus de foyers possèdant des volailles dans les systèmes à base de riz (89,5%) que dans ceux à base de mil (81,1%) ou urbains (57,1%). Les poules domestiques sont les plus communes dans tous les systèmes, suivies par les pigeons, les pintades et enfin les canards, bien que ces derniers soient absents dans la zone du mil. La plupart des femelles n’ont qu’une seule espèce mais il y a un peu plus de disersification dans la zone du riz. La taille des bandes est plus importante dans la zone du riz concernant les poulets, les pintades et les pigeons, tandis que les troupes de canards ont en moyenne plus d’oiseaux en zone urbaine. Dans toutes les espèces il y a prédominance des femelles, sauf pour les pigeons ou le sex-ratio est égal. Les conditions d’élevage concernant l’habitation, la nourriture, les soins de santé, la consommation et la commercialisation sont décrites. Les chiffres de productivité concernant la production d’oeufs, la taille des oeufs, la fertilité, la croissance et la mortalité sont fournis.
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8.
Sera obtained from dairy cattle in communal corral herds located near the city of Bamako in Mali, West Africa were sceeened using the microscopic agglutination test against 26 serovars representing 15 serogroups of Leptospira interrogans. Forty five percent (44.8%; 288/642) were positive to one or more serovars. This seroprevalence rate likely reflects infection since vaccination against leptospiral infection has not been practiced i Mali. The rate was higher among females. The most common titers were against antigens of serovars cynopteri (14.7%), hardjo (13.3%), pomona (9.2%), nona (8.1%), kambale (6.5%), grippotypyosa (6.4%), hebdomadis (6.2%), and pyrogenes (5.2%).  相似文献   
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Six hundred and ninety two cattle, slaughtered in various abattoirs in Mali between August 1983 and November 1984 were examined for evidence of Fasciola gigantica and Dicrocoelium hospes infections. A great variation in geographic prevalence was observed. Sufficient knowledge was acquired to demonstrate both the importance of fascioliasis in some areas and also the high prevalence of D. hospes in other areas. We suggest that the difference in prevalence from one geographic area to another is influenced by local climatic conditions, presence or absence of rivers and lakes, and differences in livestock management practices by various ethnic groups.  相似文献   
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