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101.
A RAPD analysis was conducted to clearify the mode of evolution of barley in the western Mediterranean basin. Twenty-nine barley accessions (Hordeum vulgare) and 13 populations of the wild progenitor (H. v. subsp. spontaneum) together with two outgroup species were analysed with seven RAPD primers, resulting in 101 polymorphic amplified fragments. Phenetic and cladistic analyses of the RAPD data resulted in trees indicating a monophyletic origin of cultivated barley, thus making a secondary domestication in Morocco unlikely. In Morocco spontaneous back mutation to wild type and crossing between wild barley (introduced from the E Mediterranean) and cultivated lines occurred, which gave rise to the local weedy forms of barley.  相似文献   
102.
Fieldwork was carried out in the north of Iran in April/May 2004. Four zones according to altitude including 20 villages and especially surrounding forests were visited. Data on uses and ethnobotany was collected through interviews that were one-on-one with respondents carefully selected to represent both male and female. Additionally a general survey of the area including other places of Savadkouh has been performed. The fruit trees and shrubs include Berberis sp., Crataegus sp., Cydonia oblonga, Diospyros lotus, Ficus carica, Malus orientalis, Mespilus germanica, Prunus cerasifera ssp. macrocarpa, Prunus spinosa, Punica granatum, and Rubus sp. Most of these are gathered from the wild, or occasionally cultivated in homegardens. The results of this study show that all of these species are used as sources of local foods and medicines. The area should be considered as an important evolutionary centre for fruit trees and shrubs and should be taken into serious consideration for discussions about fruit tree and shrub evolution. Germplasm collection activities, in situ conservation programs and interdisciplinary analysis of socioeconomic aspects of rural communications will be necessary in future studies.  相似文献   
103.
荷叶离褶伞分离驯化研究   总被引:4,自引:0,他引:4       下载免费PDF全文
试验表明,PDA培养基和金露梅葡萄糖琼脂培养基适宜对荷叶离褶伞进行组织分离和孢子分离;孢子分离获得的菌种之生长速度显著快于组织分离获得的菌种;在10~25℃的温度范围内两种分离方法都可获得成功,最适温度25℃;适宜原种与栽培种生长的配方为小麦89%、麦麸10%、葡萄糖0.5%、过磷酸钙0.5%;用棉籽壳75%、高粱12%、麦麸12%、白糖0.5%、过磷酸钙0.5%这一配方进行瓶栽,生物学效率为47.5%,显著高于其他配方和袋栽.  相似文献   
104.
With the objective of planning diversification of on-farm tree species composition, a survey was conducted in western Kenya involving a complete tree census (trees were defined as all woody or ligneous plants, including shrubs and lianas) and collection of ethnobotanical information on 201 farms. Differences between farms in diversity of the 12 most frequent use-groups were analysed by species richness, Shannon, Simpson and Berger-Parker diversity indices, and Shannon evenness and equitability. A large range of values was detected among farms and use-groups. Multiple linear regression of diversity statistics on household characteristics indicated significant relationships. However, these relationships generally explained low percentages of variation (ranging 2-44%). The connection between household characteristics and use-group diversity allows targeting specific household types with lower diversity. Farm size had a positive relationship with diversity of most use-groups. However, accumulation curves revealed that the same area carried a larger abundance and diversity when it was composed of a greater number of smaller farms. If the pattern of further subdivision of farmland in the survey area continues and the same differences between smaller and larger farms prevail, then larger diversity per unit area can be expected. Because smaller farms contain smaller diversity, however, diversification with the aim of enhancing or stabilising productivity of individual farms may become an important priority in the survey area. The results presented allow for the identification of individual farms, use-groups, and household types for which diversification is more relevant, and at the same time allow for impact monitoring.  相似文献   
105.
This study documents wild food species in a locally managed forest by the inhabitants of nine villages in the Dolakha district, Nepal. It presents data on their diversity, and traditional knowledge on plant use, propagation and local domestication collected through household and key informant interviews, forest transects inventories and herbaria verifications. Sixty-two wild food plants belonging to 36 families were recorded; most of them (80%) have multiple uses. Many of the food plants are herbaceous (24 species) and produce fruits for consumption (46%). Most of the food plants are consumed by the local communities as snacks, and are supplementary and nutritionally important especially prior to the harvest of staple foods. Elder women (>35 years) are the most knowledgeable group, being able to describe the use of 65% of all edibles as compared to only 23% described by young men (<35 years). Many villagers also possess knowledge on the modes of propagation for the food plants that may be used in the process of domestication. The local communities expressed a strong desire for the establishment of community enterprises based on the wild food resources for long-term income generation sources. To accomplish this, development of collective co-operative strategies based on assessments of the biology, size of harvestable population, sustainable harvesting techniques, and marketing value and demand of promising species would be required. Moreover domestication potential based on species identified in this paper and other species that local communities have knowledge on ought to be encouraged through incentive and policy interventions.  相似文献   
106.
Concerns exist about the limited diversity of tree species in agricultural landscapes. Complete tree inventories were carried out on 201 farms from four villages in western Kenya to establish whether significant differences in tree species composition existed between farms, and if so their magnitude and implications for new introductions and plantings. Novel types of ordination using the Hellinger ecological distance and polynomial Redundancy Analysis indicated wide heterogeneity between farms with respect to tree species composition of five niches, including homestead, cropland, fallow, woodlot, and external boundary (p ≤ 0.05). Multiple regression analysis confirmed the ordination results using the abundance of dominant species as the response variable. The relationship between location and species composition differed with those of two previous surveys. Methodological differences in sampling intensity, locations and time of sampling between these surveys could have caused the difference. The maps of spatial distribution of compositional types provided in the previous surveys were not confirmed, whereas villages were found to contain several farms with a species composition that was not typical of their village. Meaningful results about the species composition of a landscape should include several farms per village and use a sampling grid finer than 5×5 km2.  相似文献   
107.
An understanding of the inter-relationships between the traits characterising tree-to-tree variation in fruits and kernels is fundamental to the development of selected cultivars based on multiple trait selection. Using data from previously characterised marula (Sclerocarya birrea) trees in Bushbuckridge, South Africa and North Central Region of Namibia, this study examines the relationships between the different traits (fruit pulp, flesh/juice mass, and nut shell and kernel mass) as a means to determine the opportunities to develop cultivars. Strong and highly significant relationships were found between fruit mass and pulp mass in trees from South Africa and Namibia, indicating that size is a good predictor of fruit pulp production. However, fruit size is not a good predictor of nut or kernel production, as there were weak relationships between fruit and nut and/or kernel mass, which varied between sites and landuses. Generally, the relationships between fruit mass and kernel mass were weaker than between fruit mass and nut mass. Relationships between kernel mass and shell mass were generally weak. The lack of strong relationships between fruit and kernel mass does, however, imply that there are opportunities to identify trees with either big fruits/small nuts for pulp production, or trees with large kernels in relatively small fruits for kernel oil production. However, within fruits from the same tree, nuts could contain 0–4 kernels, indicating that even in trees with an inherent propensity for large kernels, improved pollination may be required to maximise kernel mass through an increase in kernel number. Finally, the relationships between percentage kernel oil content and the measured morphological traits were also very weak. The conclusions of these results are that there is merit in identifying different combinations of traits for the selection of trees producing either pulp or kernels. Consequently, fruit and kernel ‘ideotypes’ are presented as guides to the selection of elite trees for cultivar development. These results have important implications for the domestication of the species as a producer of fruits or kernels for food/beverages or cosmetic oils.  相似文献   
108.
综述了食用菌的各种育种方法和它们在育种实践应用中的部分成果,供食用菌研究人员参考。  相似文献   
109.
The commercial harvest of herbal medicine to meet the growing urban demand has become an environmentally destructive activity in many countries. Non-sustainable harvesting not only threatens the survival of medicinal plant species, but also the people that depend on them. In Suriname, the urbanization of Maroons has created a lively trade in medicinal plants, but little is known on the ecological effects of this trade. To find out whether this commercial harvest was a destructive activity, we carried out a market survey and followed commercial extractors into the forest to look for signs of overharvesting. We analyzed our results from three perspectives: the market, the harvesters and the post-harvest survival of the particular plants. Of the 249 commercial species, less than half was harvested exclusively from the wild. Most extraction took place in secondary forest or man-made vegetation close to the capital. Leaves were the main product. Apart from a few primary forest-based species (e.g., Begonia glabra), we found little evidence for declining resources. Maroons were actively cultivating and managing wild plants. Our three-way analysis enabled us to distinguish between species without sustainability problems (abundant, domesticated, cultivated, limited market value, disturbance species or surviving harvest) and species with conservation priorities. This study illustrates that the increased commercialization of medicinal plants due to urbanization does not invariably lead to declining resources and species loss. With its low population density and market dominated by disturbance species, Suriname offers good possibilities for sustainable medicinal plant extraction.  相似文献   
110.
Through the process of domestication, cultivated crops have been selected from their wild ancestors for various anthropocentrically important characteristics. Tetragonolobus palaestinus Bioss is a wild grain legume species which grows naturally on the plains and hilly areas of north Jordan and neighbouring countries. In a study of agronomic and morphological traits of wild populations of T. palaestinus at two locations, the following variables were evaluated: number and dry weight of nodules per plant, plant height, number of branches and pods per plant, pod length, number of seeds per pod, 100-seed weight, and seed weight per plant. Positive and significant correlations between 14 pairs of variables were noted, including number and dry weight of nodules per plant, plant height, number of branches and pods per plant, pod length, and seed weight per plant. The wild populations of T. palaestinus studied here appeared to be homogenous, although some of the observed variation could have arisen from variation of the environmental conditions among locations.  相似文献   
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