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1.
Water scarcity is a major factor limiting food production. Improving Livestock Water Productivity (LWP) is one of the approaches to address those problems. LWP is defined as the ratio of livestock’s beneficial outputs and services to water depleted in their production. Increasing LWP can help achieve more production per unit of water depleted. In this study we assess the spatial variability of LWP in three farming systems (rice-based, millet-based and barley-based) of the Gumera watershed in the highlands of the Blue Nile basin, Ethiopia. We collected data on land use, livestock management and climatic variables using focused group discussions, field observation and secondary data. We estimated the water depleted by evapotranspiration (ET) and beneficial animal products and services and then calculated LWP. Our results suggest that LWP is comparable with crop water productivity at watershed scales. Variability of LWP across farming systems of the Gumera watershed was apparent and this can be explained by farmers’ livelihood strategies and prevailing biophysical conditions. In view of the results there are opportunities to improve LWP: improved feed sourcing, enhancing livestock productivity and multiple livestock use strategies can help make animal production more water productive. Attempts to improve agricultural water productivity, at system scale, must recognize differences among systems and optimize resources use by system components.  相似文献   
2.
Journal of Crop Science and Biotechnology - Fusarium head blight (FHB) is one of the destructive diseases in wheat-producing areas of the world. Field experiments were conducted during the 2019...  相似文献   
3.
In this review, the genetic potential and efforts made on different aspects of potato breeding for nitrogen-use efficiency (NUE) and the possible physiological and genetic mechanisms determining NUE in potato in relation to other model crops are presented. Strategies to utilize the diverse gene pool of potato and improve the NUE in contrasting N environments are currently evaluated under field conditions using different selection approaches. So far, focused efforts have been made on the identification of potato genotypic differences which will allow for the analysis of specific components of nitrogen-use efficiency and the effect of nitrogen fertilizer on a range of physiological processes and morphological traits of potato. To my knowledge, despite the availability of genome sequence and QTLs identified for NUE and related agronomic and physiological traits in potato, and genomic information from other model crops, candidate genes on NUE have not yet been identified in potato. To maximize the success rate of potato breeding for NUE, basic knowledge how plants respond to different N regimes and other environmental conditions and use of DNA marker technology are vital.  相似文献   
4.
This study evaluated the direct antifungal activity of tiadinil [N-(3-chloro-4-methylphenyl)-4-methyl-1,2,3-thiadiazole-5-carboxamide], a systemic acquired resistance (SAR) inducer and two formulations of thymol (thymol I and thymol II) against Stagonosporopsis citrulli, the causal agent of gummy stem blight (GSB) disease of watermelon. Tiadinil, thymol I and thymol II completely inhibited the mycelial growth of S. citrulli in vitro at ≥?100 ppm. Conidial germination and germ tube elongation were completely inhibited by tiadinil at ≥?2000 ppm and by thymol-based formulations at ≥?100 ppm. A single foliar application of tiadinil at ≥?10 ppm or a single application of thymol I and II at ≥?1 ppm, 48 h before or after pathogen inoculation, significantly reduced disease severity of watermelon seedlings inoculated with 105/ml conidial suspension of S. citrulli, compared to respective nontreated controls. Plants treated with foliar application of tiadinil at ≥?1000 ppm before pathogen inoculation had significantly lower disease severity than plants that received an equivalent drench application. The efficacy of foliar application of tiadinil was affected by concentration and frequency of application. The study suggests direct antifungal activity of tiadinil, indicating a new mode of action of tiadinil against GSB disease of watermelon. The study also demonstrated direct antifungal action of thymol, a formulated active compound of essential oils, against S. citrulli and GSB disease of watermelon.  相似文献   
5.
Abstract

Two sets of field experiments under seedling transplanting and drill row seed planting methods were conducted side by side for two years during the main cropping seasons of 2017 and 2018 in Fogera Plain of northwest Ethiopia to study the effect of different sources, application methods and time of nitrogen fertilizer on growth and yield of rain-fed lowland rice. Three N sources of fertilizers (conventional Urea, Urea super-granule, and slow-release Urea) with six, one, and three application methods and times, respectively were laid out in a randomized complete block design (RCBD) in three replicates. These treatments and design were equally applied for two sets of experiments under both planting methods. Results revealed that soil-plant analysis development (SPAD) value, LAI, and biomass and grain yields of rain-fed lowland rice were highest with Urea supergranule N fertilizer sources followed by slow-release Urea and conventional Urea applications in both planting methods. Average grain yields of 3.7 and 3.8 tons ha?1 of rain-fed lowland rice were recorded with the application of Urea supergranule N source fertilizer under seedling transplanting and drill row seed planting methods, respectively. Hence, using Urea supergranule tablet is recommendable for getting better grain yield of rain-fed lowland rice without yield penalty in both planting methods.  相似文献   
6.
Sanitation from harvest to storage is a key factor in eliminating sources of infection and reducing levels of mycotoxigenic fungal invasion, and thereby mycotoxin contamination. This study was conducted at Haramaya University, Eastern Ethiopia to investigate the effects of threshing methods on fungal invasion and mycotoxin contamination of sorghum grain. The methods included threshing on bare ground, cow-dung-painted ground, concrete asphalt and canvas. The threshed grain was kept separately in bags in three replications in a completely randomized design and stored for five months. The results revealed that all the sorghum grain samples taken from different threshing methods were contaminated with both Aspergillus and Fusarium species. There were variations in fungal invasion between samples taken immediately after threshing and stored samples. The level of Aspergillus spp. invasion was much higher in the latter in sorghum grain threshed on bare ground. The concentration of aflatoxin B1 was gradually increased, whereas the total fumonisin concentration was decreased with the storage duration both in 2013 and 2014. On stored sorghum grain, the highest (1.97 µg kg?1) and the lowest (0.70 µg kg?1) mean aflatoxin B1 concentrations were recorded from sorghum grains threshed on bare ground and on canvas, respectively. Sorghum grain obtained from canvas threshing method had significantly lower mean total fumonisin content (142.5, 54.9 µg kg?1) than grain from the other methods at threshing. The current work clearly demonstrated the effect that threshing might have on fungal invasion and mycotoxin contamination of sorghum grains. .  相似文献   
7.
Tropical Animal Health and Production - A cross-sectional study with simple random sampling approach was conducted from November 2017 to May 2018 with the objectives of estimating the prevalence of...  相似文献   
8.
9.
Ethiopia is basically an agricultural and pastoral country. Agriculture dominates the Ethiopian life to the extent that little progress can be made unless agriculture is attacked directly. Ethiopia is a country of peasants with primitive agriculture. The physical potential for sharply increased agriculture is high but the obstacles for development are immense still, despite recent government attempts.The two dominant agricultural systems in Ethiopia are the mixed agriculture of the highlands, where both crops and livestock production are integrated, and pastoralism in the lowlands. The mixed agriculture exhibits several subsystems. Commercial agriculture using the river basins, such as the Awash Basin, is a recent phenomenon.Agricultural research as a formal activity and national programme is less than twenty-five years old and has undergone three formative stages reflecting the level of government commitment to agricultural development. The agricultural research system has now entered a new period where policy and infrastructures are being well laid down with emphasis on rural development. But these developments must be matched by greatly improved human and financial resource allocations.  相似文献   
10.
Tuberculosis (TB) is an important zoonosis affecting a wide range of hosts. An abattoir study was conducted on 1,536 randomly selected male goats slaughtered at Modjo Modern Export Abattoir to determine the prevalence of tuberculosis in slaughtered goats. Carcasses and organs of all the study animals were first examined by routine meat inspection followed by detailed meat inspection. Samples from tuberculous lesions were cultured for mycobacterial isolation and identification. Histopathology was done on 31 samples with tuberculous lesions. Detailed meat inspection detected 65 (4.2%; 95% confidence interval (CI) = 3.3–5.4%) tuberculous lesions. From these, 20 (30.8%) samples were confirmed mycobacterium positive on culture, out of which 18 were Mycobacterium bovis and two were Mycobacterium tuberculosis. Routine meat inspection failed to detect tuberculous lesions in 23% of carcasses with TB lesions detected by detailed examination. However, no statistically significant difference was observed between both methods in detecting tuberculous lesions (Kappa = 0.87). Origin and age of the goats did not statistically affect the disease prevalence (P > 0.05). Histopathologic lesions were observed in 21 samples (68%; 95% CI = 50.1–81.4%) out of the 31 carcasses with gross tuberculous lesions examined by histopathology. Eighteen (58%) tuberculous samples positive for histopathology were also culture positive. The sensitivity and specificity of histopathology were 90% (95% CI = 76.9–100%) and 72.7% (95% CI = 46.4–99%), respectively, using culture as a reference test. To the best of our knowledge, this is the first report of caprine tuberculosis from Ethiopia. Further studies are required at the farm level to determine the prevalence of tuberculosis in the general goat population.  相似文献   
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