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41.
42.
ABSTRACT

A socio-economic survey of production systems was carried out in four out of the eight states that make up the southwest agricultural zone of Nigeria. A total of 157 minor grain legume farmers selected by multi-stage sampling were interviewed using structured questionnaires. The study shows that lima bean, pigeon pea, African yam bean, and bambara groundnut are the prominent minor grain legumes grown on less than 10% of the total cultivated land area. The minor grain legumes are grown on an average land size ranging from 0.2 to 0.4ha and predominantly in mixture with crops like cassava, maize, yam, sorghum, cocoyam, etc. The use of modern inputs like herbicides, pesticides, fertilizers, and improved varieties is uncommon in minor legume production systems. The cultivation of these legumes is more popular among the older members of the farming communities, about 78% of which are above 40 years of age. The average yield of the legumes on farms is considerably low, estimated at 271kg/ha, 265kg/ha, 174kg/ha, and 275kg/ha for lima bean, pigeon pea, African yambean, and bambara groundnut, respectively. Major constraints identified by the farmers include low market demand, inadequate seed supply, high cost of labour, and low yield. Research work is therefore needed in agronomy and breeding for improved yield and utilization for expanded market and, consequently, increased production.  相似文献   
43.
Five plant-based weaning foods (WF) (Dietrend, Jot-M, Soy, Ang and Vic-T) locallyprepared in Jos, Nigeria were analyzed by gas-liquid chromatography,reverse-phase high performance liquid chromatography, and atomicemission spectrometry with inductively coupled plasma to determine theirfatty acid (FA), amino acid, and trace mineral contents, respectively.Results of these direct analyses were compared to expected values derivedfrom food composition tables prepared by the United States Department of Agriculture (USDA). Additionally, results were compared against recommendednutrient values, using breast milk as the standard for FA content andrecommended dietary allowances (RDA) for amino acid and mineral contents.The overall nutritional value of the five WF varied considerably and thequantities of particular nutrients determined by direct analysis differedmarkedly from those estimated using USDA food tables. Comparison of WFfatty acid composition relative to the RDA recommendations and a humanmilk standard revealed a much higher proportion of both linoleic (35–55wt%) and -linolenic acids (1%–7 wt%) relative to human milklipids (11%–12% and 0.8%–0.9% wt, respectively); however, the WFwere devoid of arachidonic acid and docosahexaenoic acid. Soy containedthe highest amounts of linoleic acid (59.7 mg/g) and -linolenicacid (7.46 mg/g) compared to the other four WF (10.2–41.0 and 0.35–3.18 mg/g, respectively). The linoleic acid/-linolenic acid ratio was within the recommended range (5:1 to 10:1) in only Jot-M (10:1)and Soy (8:1). Dietrend, Vic-T and Ang, containedlinoleic/-linolenic ratios of 12:1, 29:1, and 82:1, respectively.The Soy weaning food would provide the most protein (24.3 g/day), basedon an estimated daily intake of 65 g of weaning food by a normalsix-month-old infant, compared to Jot-M (11.9 g/day), Dietrend (11.7g/day), Ang (8.07 g/day) and Vic-T (7.26 g/day). The protein RDA forchildren up to 1 year of age is 13–14 g/day. Comparison of the mineralcontents of the WF to the RDAs for various minerals indicated that all fivewould provide suboptimal amounts of calcium (16 to 250 mg/day) andzinc (1.42 to 3.56 mg/day) compared to respective RDAs of400 mg/day and 5 mg/day.These data show that the Soy weaning food is an excellent source of linoleicacid and -linolenic acid, as well as being a good source of highquality protein. Jot-M and Dietrend provide useful amounts of the essentialFA; however, it is advisable to reevaluate the composition of Ang andVic-T to find ways to improve the linoleic/-linolenic ratio of eachand increase their total protein content. These results document theshortcomings of using published food composition tables based on foods inAmerica when devising weaning foods based on ingredients in another partof the world.  相似文献   
44.

Background

A survey was conducted to determine the prevalence of campylobacteriosis and trichomonosis, and their concurrence with brucellosis, in cattle in three states of northern Nigeria.

Methods

A total of 602 preputial samples was collected from bulls in 250 herds and tested using culture and identification. Various indigenous and exotic breeds were studied and four major management systems were encountered. Age of the cattle was estimated using dentition, farm records or cornual rings.

Results

The estimated true animal-level prevalence of Campylobacter fetus infection was 16.4% (95% CI: 13.0-20.7), of which 18.5% was C. f. fetus and 81.5% was C. f. venerealis. Of the latter, 92% were C. f. venerealis biovar intermedius strains. Animal-level prevalences in Adamawa, Kano and Kaduna states were 31.8%, 11.6% and 8.3% respectively, and were highest in bulls >7 years old (33.4%) and in the Gudali breed (28.8%). Of the 250 herds, 78 (25.5%, 95% CI: 19.4-32.7) had at least one infected bull, and herd prevalence was highest in the pastoral management system (43.5%). After adjustment for confounding using multivariable analysis, the odds of C. fetus infection were highest in Adamawa state (P < 0.01), in the pastoral management system (P < 0.01), and in bulls >7 years old (P = 0.01), and tended to be higher in Bos taurus breeds (P = 0.06). There was a strong positive association between the presence of campylobacteriosis and brucellosis (P < 0.01), both within bulls (OR = 8.3) and within herds (OR = 16.0). Trichomonosis was not detected in any herds.

Conclusion

Bovine genital campylobacteriosis is prevalent particularly in the pastoral management system in northern Nigeria, with C. f. venerealis biovar intermedius as the major aetiology. There was a strong positive correlation between the occurrence of campylobacteriosis and brucellosis. No evidence of trichomonosis was found in herds in this study.  相似文献   
45.
Field studies on the nature of competition and the effects of various planting patterns on maize/cowpea intercrop yields were conducted in Southwestern Nigeria. Relative Crowding Coefficient values indicated that maize dominated cowpea. The magnitude of competition between maize and cowpea is related to season and nitrogen fertilizer. Based on grain yields, maize and cowpea compete for N only when it was applied but tended to derive it from different sources in the absence of applied N.
Spatial arrangements designed to increase light reaching intercropped cowpea included alternate and double rows of cowpeas between maize rows. These did not, however, increase grain yields of cowpeas over those intercropped with maize in the same row.  相似文献   
46.
Abstract

Village weaverbirds (Ploceus cucullatus Muller) normally feed on early maize in the morning (0800 to 1100 h) and evening (1600 to 1800 h) in southwestern Nigeria. However, when disturbed the birds feed during all the hours of daylight, and to be effective bird scaring would have to persist throughout the day. Developing grains are eaten, but rarely dry grains. The period of active bird scaring can therefore be reduced to about two weeks. In 1977 the mean percentage damage varied from 2.2 ± 0.3% in plots with dry ears to 34.1 ± 12.7% in plots with fresh ears, but in 1978 the situation was reversed with 17.7 ± 3.1% damage in plots with dry ears to 1.1 ± 0.2% in plots with fresh ears. The pattern of damage to early maize is associated with the annual rainfall, which determines the occurrence of lepidopterous larvae and wild sorghum (Sorghum arundicearum Stapf) which form alternative food items for the birds. Less than 2% of late maize ears was damaged since alternative food resources were abundant. Only early maize may need protecting from bird damage, but there was no definite relationship between time of planting and amount of damage caused.  相似文献   
47.
The yields of two intercropped cocoa/kola plots at the Cocoa Research Institute of Nigeria, Ibadan, (W8/1 and C3/1), were compared with the yields of monoculture plots (N4/A and W1/2). It was found that 1.75 ha of monoculture plot gave the same crop yield (kg/ha) as 1.00 ha of mixed crop. The cocoa component started fruiting earlier than kola and also continued to yield annuall so there was no crop failure in any year.  相似文献   
48.
In view of the recurrent drought and human population pressures which have drastically reduced the density of pasture species within the Nigerian savannas, the nomadic herdsmen rely mostly on silvipastoralism, grazing their herds in Eucalyptus plantations. In this study, the population of understorey forage and non-forage speicies and the relative light intensities on the forest floors of two Eucalyptus species, viz: E. citridodora, and E. camaldlensis were compared with those of open savanna lands at Kabama, Samaru and Guga, all within the Northern Guinea savanna zone.At normal 3 m by 3 m spacing between trees, the herbages were fewer in the plantations and the E. citridora plantation had only about half the number of species observed under E. camaldlensis in the same and other sites despite similarities in light intensity levels in all the plantations. This information forms a guideline in using eucalyptus silvo-pastoral farms.  相似文献   
49.
Clinical signs of severe bronchopneumonia, including anorexia, coughing, nasal discharge, dyspnoea, diarrhoea, distension of the neck, lethargy, recumbency, lameness preceding collapse, and death were observed among a herd of Holstein–Friesian dairy cattle. The outbreak occurred over a 30-day period, and attack and case-fatality rates were 0.4% and 50%, respectively. At necropsy, extensive consolidation in the cranioventral parts of the lungs was observed. Histologically, a severe acute bronchopneumonia with slight pleuritis was present. Both pathological and bacteriological evaluation of the lungs incriminated Histophilus somni (heavy growth). Supplementary laboratory investigations also isolated Clostridium and Klebsiella species (scanty growth) from the lungs. Histophilosis in cattle was confirmed for the first time in Nigeria.  相似文献   
50.
Experiments were conducted in 1995 and 1996 to determine the effects of different sources of nutrients on the infestation of fruits of five pepper varieties by Atherigona orientalis (Schiner). Different sources of nutrients — chicken droppings, plant residues (compost manure), wood ash and NPK (chemical fertilizer) — were used in the planting of each of the five pepper varieties [Nsukka yellow, Atarugu, and Sweet pepper, all of Capsicum annum; Bird's eye chilli and Local medium red (Ogoni pepper) both of C. frutescens ]. In 1995 plantings, pepper plots of Nsukka yellow and Atarugu varieties that received chicken droppings as source of nutrients suffered the highest percentage fruit damage of 90.7 % and 80.8 %, respectively. Pepper plots of Nsukka yellow, Atarugu, Sweet pepper and Local medium red grown in 1996 and treated with chicken droppings suffered the highest percentage fruit damage of 93.7 %, 56.6 % and 52.2 %, respectively. Plots of the Bird's eye chilli variety received minimal or no fruit damage in all. Pepper fruits in the control plots also did not undergo A. orientalis attack. Chicken droppings offered the lowest Relative Protection (RP) values to most pepper varieties in 1995 and 1996. NPK chemical fertilizer offered the highest percentage RP values in 1995 and wood ash offered the highest RP in 1996 to most pepper varieties. Also, wood ash in both 1995 and 1996 offered a relatively high percentage RP to most pepper varieties. Compost manure offered a moderate percentage RP in both years.  相似文献   
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