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61.
62.
为今后利用青藏高原野牦牛资源,在青海省大通种牛场对1头野牦公牛和6头1/2野血牦公牛采取人牛固定管理、长期相处、诱训亲善等系列措施,达到能够采精,完成驯化平均时间为165天,完成采精训练平均时间为28.4天,采精训练次数平均11.06次。 相似文献
63.
M. Essadki N. Ouazzani R. Lumaret M. Moumni 《Genetic Resources and Crop Evolution》2006,53(3):475-482
In olive tree (Olea europaea L.), 12 varieties (or cultivars) representing the main domesticated material used in Morocco and 19 olive cultivars used
extensively in five countries of the western Mediterranean Basin, were analysed using inter-simple sequences repeat (ISSR)
markers which had never been used previously for extensive discrimination of cultivars. Four selected primers produced a total
of 26 polymorphic reproducible amplification fragments. Combinations of these ISSR markers allowed to identify 25 of the 31
cultivars. Two additional combinations were distinguished, each corresponding to three Moroccan cultivars or local varieties.
Evidence of a multiclonal composition in the widely cultivated variety ‘Picholine marocaine’ was obtained by the identification
of three genotypes within the four morphologically distinct clones analysed in the variety. In the UPGMA phenogram based on
the proportion of shared ISSR fragments, five groups of cultivars were distinguished at the 40% critical value of similarity.
Four of the groups contained varieties from various geographic origins, as the consequence of successive human migrations
which favoured olive dispersion throughout the Mediterranean Basin. However, the fifth group gathered together 9 of the 12
Moroccan cultivars and very few cultivated clones from Greece and Spain. The results suggest that most of the Moroccan cultivars
are closely related and likely originated from local domestication. 相似文献
64.
B.?KhadariEmail author C.?Grout S.?Santoni F.?Kjellberg 《Genetic Resources and Crop Evolution》2005,52(1):97-109
Patterns of mitochondrial DNA (mtDNA) variation revealed by RFLP were investigated for 63 individuals of the common fig, Ficus carica L., in 15 supposedly natural populations throughout the Mediterranean basin. Fifteen haplotypes were detected using one restriction enzyme (HindIII) and four probes (atp, coxIII, nad3rpsl2 and rps12). Mitochondrial diversity within populations varied from monomorphic to entirely polymorphic and population differentiation was high (FST = 0.323, P < 10–5). Seven groups of populations were defined on the basis of genetic and geographic proximity and lead to significant pairwise FST estimates except for the Corsican group which was similar to the Moroccan one. Fig populations were structured into three clusters: Balearic, West and East Mediterranean gene pools. The low diversity and strong differentiation of the Balearic populations strongly supports an ancient origin and the presence of natural populations in this area before domestication. Significant genetic differentiation between the West and East Mediterranean probably also reflects a diversification of the common fig over the Mediterranean basin preceding domestication. In contrast, Italian island populations seem to result from introduced cultivated fig since they present continental haplotypes. Our study represents a first mtDNA polymorphism survey and these indications should be confirmed by analysing local cultivated forms from the Baleares and from Italian islands and further natural populations from the East Mediterranean. 相似文献
65.
Alma?Tinoco Alejandro?CasasEmail author Rosaura?Luna Ken?Oyama 《Genetic Resources and Crop Evolution》2005,52(5):525-538
Escontria chiotilla is a columnar cactus that grows in the arid and semiarid lands of Central Mexico and produces edible fruit with economic.
In the wild, this plant species is distributed as part of thorn-scrub and tropical deciduous forests, but in the Tehuacán
Valley also occurs in silvicultural managed in situ populations, in which people practise artificial selection enhancing phenotypes with larger fruits. The population genetics
of wild and managed populations was studied to analyse the effects of management on genetic structure of E. chiotilla. A total of 150 individuals from six populations were studied, analysing 13 loci for eight enzymes by starch gel electrophoresis.
The genetic variation in wild populations was significantly higher than in managed populations (Ho = 0.079, He = 0.134, HT = 0.370, and Ho = 0.052, He = 0.110, HT = 0.298, respectively), indicating that silvicultural management has caused a reduction of the genetic variation in populations.
Most of the genetic variation in both wild and managed populations occurs within populations (DST = 0.027 in the wild and 0.018 in managed populations). The genetic distance coefficients were slightly different for silvicultural
managed populations than in wild ones, illustrating an incipient effect of management on the genetic structure of populations.
However, values of NmGST = 3.845 and NmFST = 3.848 indicate that a high gene flow counteracts the effects of human selection on the differentiation of populations. 相似文献
66.
J. Gebauer K. El-Siddig B. A. El Tahir A. A. Salih G. Ebert K. Hammer 《Genetic Resources and Crop Evolution》2007,54(8):1701-1708
The small leaved white cross berry (Grewia tenax [Forssk.] Fiori) is a fruit-producing deciduous shrub or small tree of widespread occurrence in semi-arid and sub-humid tropical
climates. Despite its well-recognized potential and high prices on local markets, there are no commercial plantations in Sudan.
Wild plants have continuously been used to meet the growing commercial demand for their fruits. Recently, there has been an
increased interest in finding alternative, potentially high-value cash crops to improve the income of small farmers who are
currently depending upon growing and selling millet (Pennisetum glaucum [L.] R. Br.), sorghum (Sorghum bicolor [L.] Moench), sesame (Sesamum indicum L.), and groundnut (Arachis hypogaea L.). G. tenax has often been cited as a prime candidate for domestication as a useful horticultural plant. One major factor hampering this
development is the limited and scattered knowledge available on this species. The purpose of this paper is to highlight the
importance of G. tenax by providing information on its botanical and horticultural characteristics in the effort to promote its domestication and
commercialization for regional and global markets. 相似文献
67.
Karl?HammerEmail author Gaetano?Laghetti Klaus?Pistrick 《Genetic Resources and Crop Evolution》2005,52(2):215-219
Calamintha nepeta and Micromeria thymifolia have been traditionally used in the Mediterranean area as condiments and medicinal plants for a long time. Whereas in parts of Italy C. nepeta (special recipes have been developed in Lazio and Tuscany) is also an established garden plant showing different evolutionary products and their interaction among each other and the wild progenitor, M. thymifolia is being developed into a new crop plant. Both plants and their uses are described with regard to Italy. There is a marked tendency to broaden the use of condiments and spices which results in new crop plants which have to be documented and elaborated in further studies. Many species of Labiatae are predisposed to use by man and new items can be found even in areas which have to be considered as well studied. 相似文献
68.
Gabriella Sonnante Anna Vittoria Carluccio Roser Vilatersana Domenico Pignone 《Genetic Resources and Crop Evolution》2007,54(3):483-495
The evolutionary history of artichoke and cultivated cardoon and their relationships to wild allies of the genus Cynara are not fully understood yet. To try resolve the evolutionary patterns leading to the domestication of these two crops, a
study of molecular evolution was undertaken. The species C. cardunculus, including artichoke, cultivated and wild cardoon, together with four wild Cynara species were taken into consideration. Internal (ITS) and external (ETS) rDNA transcribed spacers were used as markers of
nuclear genome, the psbA-trnH spacer as a marker of chloroplast genome. Sequences were analysed using phylogenetic analysis packages. Molecular data indicate
that the whole genus is quite recent and that the domestication of artichoke and cultivated cardoon, crops diverging for reproduction
system and use, are independent events which diverge in time and space. As for wild Cynara species, an evolutionary pattern consistent with their present geographical distribution was hypothesized in relation to
the climatic changes occurring in the Mediterranean during the last 20 millennia: C. humilis and C. cornigera appeared to have differentiated first, C. syriaca and C. baetica were differentiated in a second period, while C. cardunculus showed to be the most recent and plastic species. The high plasticity of C. cardunculus has not only allowed its nowadays wide distribution, but has also given the potential for domestication.
Dedicated to the memory of Richard Neville Lester (1937–2006) who greatly contributed to the understanding of the evolution,
domestication, and genetic resources of eggplants as well as to the biosystematics and taxonomy of allied species.
IGV Publication N. 78 of the Institute of Plant Genetics, CNR 相似文献
69.
The present study, using RAPD analysis, was undertaken to characterize genetic variation in domesticated cowpea and its wild progenitor, as well as their relationships. The materials used consisted of 26 domesticated accessions, including accessions from each of the five cultivar-group, and 30 wild/weedy accessions, including accessions from West, East and southern Africa. A total of 28 primers generated 202 RAPD bands. One hundred and eight bands were polymorphic among the domesticated compared to 181 among wild/weedy cowpea accessions. Wild accessions were more diverse in East Africa, which is the likely area of origin of V. unguiculata var. spontanea. Var. spontanea is supposed to have spread westward and southward, with a loss of variability, loss counterbalanceed in southern Africa by introgressions with local perennial subspecies. Although the variabilty of domesticated cowpea was the highest ever recorded, cultivar-groups were poorly resolved, and several results obtained with isozyme data were not confirmed here. However primitive cultivars were more diverse than evolved cultivars, which still suggests two consecutive bottlenecks within domesticated cowpea evolution. As isozymes and AFLP markers, although with a larger number of markers, RAPD data confirmed the single domestication hypothesis, the gap between wild and domesticated cowpea, and the widespread introgression phenomena between wild and domesticated cowpea. 相似文献
70.