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1.
Studies were performed on 25 egg batches ofThaumetopoea pityocampa (Den. & Schiff.) collected onPinus pinaster Ait. on 29. XI. 1995, in the Atlas Mountains of Morocco near Marrakech at 1400-1800 m above sea level. All the egg masses had been deposited in the autumn of 1995 and were exposed to the parasitoids throughout the developmental period of the host. In 1996, the egg batches, kept singly in test tubes, were observed almost daily. Emerged parasitoids were recorded and separated. The final analyses were made in November 1996 based on the meconia and remains of the emerged or the dead parasitoids in the eggs. In all cases, oviposition occurred from the base to the tip of the needles, distances varying up to 62 mm from the base. The mean number of eggs per batch was 175 (range 34-245), the number of egg-rows varied between 6 and 11, and a 1-cm egg-row contained a mean of 9 eggs. Caterpillars hatched from 72. 7% of the eggs; total mortality of the eggs was thus 27. 3%. The impact of egg parasitoids was 21. 4%. Most of the parasitized eggs were attacked byBaryscapus servadeii (Dom.) followed byOoencyrtus pityocampae (Mercet). Males (1. 5%) were found only in B. servadeii. The emergence rate ofO. pityocampae was much higher in the year of host oviposition than in the following year. B. servadeii emerged in equal numbers before and after hibernation, and in the subsequent year in equal numbers in spring and autumn. The high rate of emergence ofB. servadeii in April-May is discussed in relation to the embryonic development ofThaumetopoea bonjeani (Powel) until the end of winter, as an alternative host ofB. servadeii in the Atlas region.  相似文献   
2.
Increasing emergence of salmonellosis presents a threat to the effective control of foodborne disease in humans. The purpose of this study was to evaluate the prevalence of drug susceptibility and molecular characteristics of non-typhoidal Salmonella (NTS) isolated from laying hens (LH) in 3 Moroccan regions, Rabat-Salé-Zemmour-Zaër (RSZZ), Souss-Massa-Drâa (SMD), and the grand Casablanca (GC). A total of 351 samples were collected from 30 consumer egg laying houses at the end of the egg laying period from April to July 2011. Sixty-four out of these 351 examined samples were contaminated by Salmonella. The Salmonella isolated strains were then serotyped and tested for drug susceptibility and analyzed by polymerase chain reaction (PCR) for the presence of the invasion-associated genes invA and spvC and nalidixic acid resistance-associated qnr gene. The prevalence of NTS infection in LH was estimated to be 73.3%. Seven Salmonella enterica serovars were identified: Enteritidis (37.5%), Kentucky (31.2%), Infantis (10.9%), Typhimurium (6.2%), Thompson (6.2%), Agona (4.6%), and Amsterdam (3.1%). Drug susceptibility testing showed that 65.6% of Salmonella were resistant to at least one antibiotic and 25% were resistant to ciprofloxacin. All isolates were positive for the invasion gene invA and 28% of them were positive for the virulence gene spvC. All nalidixic acid-resistant S. Enteritidis isolates were negative for qnr plasmid genes. Our findings clearly suggest the necessity to establish an NTS monitoring and control program for LH in Morocco.  相似文献   
3.
This paper accepts that assessing the performance of irrigated agriculture is difficult because being multi-dimensional it requires a multi-disciplinary approach. Public irrigation schemes may have a number of often competing objectives and are assessed by interest groups with differing values and perspectives. A wide range of performance indicators are thus required. Some of these and the complex inter-relationships that may exist in the system are illustrated.  相似文献   
4.
中国茶叶在摩洛哥市场的价格及需求弹性分析   总被引:2,自引:0,他引:2  
许咏梅  苏祝成 《茶叶》2006,32(4):212-214
摩洛哥是中国茶叶的第一大进口国,本文分析了中国茶叶出口摩洛哥市场的价格状况,在此基础上对需求弹性进行了测算,结果表明,中国茶叶垄断了摩洛哥市场,主导着摩洛哥茶叶市场价格。  相似文献   
5.
In the Eastern Rif of N Morocco, soil conservation is seriously threatened by water erosion. Large areas of soil have reached an irreversible state of degradation. In this study, the 137Cs technique was used to quantify erosion rates and identify the main factors involved in the erosion process based on a representative catchment of the Eastern Rif. To estimate erosion rates in terms of the main factors affecting soil losses, samples were collected taking into account the lithology, slope and land use along six selected transects within the Boussouab catchment. The transects were representative of the main land uses and physiographic characteristics of that Rif sector. The reference inventory for the area was established at a stable, well preserved, matorral site (value of 4250 Bq m− 2). All the sampling sites were eroded and 137Cs inventories varied widely (between 245 and 3670 Bq m− 2). The effective soil losses were also highly variable (between 5.1 and 48.8 t ha− 1 yr− 1). Soil losses varied with land use. The lowest average values were on matorral and fallow land (10.5 and 15.2 t ha− 1 yr− 1, respectively) but much higher with alfa vegetation or cereal crops (31.6 and 27.3, respectively). The highest erosion rate was on a badland transect at the more eroded part of the catchment, with rates exceeding 40 t ha− 1 yr− 1 and reaching a maximum of 48.8 t ha− 1 yr− 1.The average soil losses increased by more than 100% when the slope increased from 10° (17.7 t ha− 1 yr− 1) to 25° (40. 8 t ha− 1 yr− 1). Similar results were obtained when comparing erosion rates in soils that were covered by matorral with respect to those under cultivation. Lithology was also a key factor affecting soil loss. Soils on marls were more erodible and the average erosion rates reached 29.36 t ha− 1 yr− 1, which was twice as high as soils on the glacis and old fluvial terraces (average rates of 14.98 t ha− 1 yr− 1). The radiometric approach was very useful to quantify erosion rates and to examine the pattern of soil movement. The analysis of main erosion factors can help to promote rational soil use and establish conservation strategies in the study area.  相似文献   
6.
7.
Over two consecutive years, weekly examinations for the presence of nematodes were conducted on 185 stomachs from donkeys originating mainly from the Rabat, Casablanca and Settat regions of Morocco. All the animals, except one, were infected by at least one of four helminth species.Trichostrongylus axei was found in 93.5%,Habronema muscae in 89.7%,H. majus in 85.4% andDraschia megastoma in 1.1% of donkeys. Most animals were infected by two (23.8%) or three (71.9%) species. High burdens ofT. axei were observed in the winter of both years and in the mid-summer of the second year. Peak burdens ofHabronema were found at various times throughout both years. There were more adultH. majus thanH. muscae. The periods of peak levels of infection by these parasites were related to environmental conditions suitable for the development and survival of infective larvae ofT. axei and for the build-up of muscid fly vectors ofHabronema andDraschia spp.  相似文献   
8.
The identification of burnt forests and their monitoring provide essential information for the suitable management and conservation of these ecosystems. This research focuses on the use of remote sensing with MODIS sensor data in a Mediterranean environment, precisely in the Rif region known for its high occurrence of forest fires and the largest burnt areas in Morocco. It mapped the burnt areas during the summer of 2016 using spectral indices from MODIS images, namely the Normalized Burn Ratio (NBR) and the Burnt Area Index for MODIS (BAIM). Two field surveys were used to calibrate spectral indices and validate the maps. First, a monotemporal analysis using a single pre-fire image determined the appropriate threshold of the spectral indices (BAIM and NBR) for burn detecting. Secondly, a multitemporal method was applied based on dBAIM and dNBR images which represented pre-fire and postfire differences of the BAIM and NBR images, respectively. The results show that separate use of monotemporal postfire and multitemporal methods produced an overestimation of the burnt areas. Finally, we propose a new algorithm combining both methods for burnt area mapping that we name Burnt Area Algorithm. MCD45A1 and MCD64A1 MODIS burnt area products were compared to the proposed algorithm. Validation of the estimated burnt areas using reference data of the Moroccan High Commission for Water, Forests and Fight against Desertification showed satisfactory results using the proposed algorithm, with a determination coefficient of 0.68 and a root mean square error of 44.0 ha.  相似文献   
9.
The assessment of rangeland productivity in semi-extensively grazed arid rangelands is a prerequisite for livestock management in relation to sustainable use of pastoral resources. The objective of this study was to assess rangeland productivity based on normalised difference vegetation index (NDVI) images. Data on phytomass were measured on 61 field samples in arid rangelands of Morocco, covering various rangeland categories during autumn (November) and spring (April), i.e. when phytomass is at low and high levels, respectively, for two consecutive years (2008 and 2009). Dekadal EROS Moderate Resolution Imaging Spectroradiometer (eMODIS) NDVI data were linearly regressed to field measurements for these four periods. Results show that phytomass values were correlated with NDVI during spring, with R2 and RMSE values of 0.82 and 0.3 t ha?1, respectively. This study indicates there is a high potential for operational use of remotely sensed data to estimate rangeland phytomass of semi-extensively grazed rangelands.  相似文献   
10.
For many years, large-scale irrigation around the world was based on state-driven water management and on a planned innovation process and diffusionist extension services. The purpose of this study is to show that formal extension services are not the only intermediaries of innovation and that local innovations take place at the initiative of farmers even in state-driven irrigation schemes. The study addressed changes in farming systems in a large-scale irrigation scheme in Morocco from two angles: a review of planned innovations and analysis of the actual innovation process at the village level. We show that the implementation of the large-scale irrigation scheme contributed to agricultural development, but often indirectly, and that it was not the only source of innovation. We also show how these results support recent thinking on innovation systems. Today, informal labour, neighbour and marketing networks are the main innovation intermediaries. New practices in agricultural extension are required to facilitate local innovations and to link farmers to more global innovation networks.  相似文献   
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