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21.
Journal of Crop Science and Biotechnology - Flower formation is one of the main developmental stages in the life cycle of flowering plants that can be used as a model system to elucidate the...  相似文献   
22.
Synergism of an oil of Azadirachta indica, a powdered extract of Allium sativum bulbs and an oleoresin of Zingiber officinale rhizomes by piperonyl butoxide and MGK-264 was studied against the snails Lymnaea acuminata and Indoplanorbis exustus. The active components of these plant-derived molluscicides, respectively azadirachtin, allicin and [6]gingerol, were also combined with these synergists. Both piperonyl butoxide and MGK-264 enhanced the toxicity of all of the test compounds. The response of snails to the synergised mixtures was both time- and dose-dependent. © 1998 Society of Chemical Industry  相似文献   
23.
Rosa damascena Mill is the most important scented rose species cultivated for rose oil production. Rosa bourboniana L. (Edward rose), a related species, is popular on account of its longer blooming period and ease of propagation. With an aim to combine the oil quality of R. damascena and recurrent flowering habit of R. bourboniana, two cultivars (Jwala and Himroz) of R. damascena were crossed with R. bourboniana. The F1 hybrids obtained were evaluated using morphological, random amplified polymorphic DNA (RAPD) and microsatellite (SSR) markers. Twenty-two selected RAPD and three SSR primer pairs were utilized for hybrid identification. According to presence or absence of bands RAPD and SSR markers were classified into seven types of markers. The bands specific for the pollen parent and occurring in the hybrids were good markers to confirm the hybridity. The non-parental bands expressing uniquely in hybrids were effective in distinguishing the hybrids from each other. Cluster analysis, based on Jaccard's similarity coefficient using unweighted pair group method based on arithmetic mean (UPGMA), reliably discriminated the hybrids into two main clusters. These results indicate the practical usefulness of RAPD and SSR markers in hybrid identification in scented roses. The approach is advantageous for its rapidity and simplicity, for identification of hybrids at the juvenile stage. One of the studied morphological traits – prickle density, can also complement in the identification of interspecific hybrids between R. damscena (♀) and R. bourboniana (♂).  相似文献   
24.
Sood  Renuka  Prabha  Kiran  Govil  Suman  Gupta  Shrish C. 《Euphytica》1982,31(2):333-339
Summary Ipomoea cairica Sweet (Convolvulaceae) exhibits sporophytic self-incompatibility. This has partially been overcome under in vitro conditions, by treating the pollen and/or stigma with 10-5–10-1M indole-3-acetic acid (IAA), the optimum being 10-2M. The self-pollen. which otherwise does not even stick to stigma. germinates after self-pollination provided only one or both the partners are treated. The pollen tubes not only penetrate stigmatic papillae but also traverse the whole length of the style, at least in optimum experimental combinations.  相似文献   
25.
Genetic Resources and Crop Evolution - Garcinia L. is a pantropically distributed genus with high species richness in South East Asia. It is a tropical evergreen plant with distinct morphological...  相似文献   
26.
We present a dry deposition modeling approach that includesvegetation-atmosphere interactions through photosynthesis/carbonassimilation relationships. Gas deposition velocity (V d) is calculated using an electrical resistance-analogapproach in a coupled soil-vegetation-atmosphere transfer (SVAT)model. For this, a photosynthesis-based surface evapotranspirationand gas exchange model is dynamically coupled to an atmospheric model with prognostic soil hydrology andsurface energy balance. The effective surface resistance(composed of aerodynamic, boundary layer, and canopy-basedresistances) is calculated for a realistic and fully interactiveestimation of gaseous deposition velocity over natural surfaces.Based on this coupled framework, the photosynthesis-based gasdeposition approach is evaluated using observed depositionvelocity estimates for ozone over a soybean field (C3photosynthesis pathway) and a corn field (C4 photosynthesispathway). Overall, observed V d and modeled V d show good qualitative and quantitative agreement.Results suggest that photosynthesis-based physiologicalapproaches can be adopted to efficiently develop depositionvelocity estimates over natural surfaces. Such a physiologicalapproach can also be used for generalizing results from fieldmeasurements and for investigating the controlling relationshipsamong various atmospheric and surface variables in estimatingdeposition velocity.  相似文献   
27.
Summary

The roles of sucrose synthase and invertases were explored in relation to petal senescence in rose (Rosa hybrida L.). A developmental shift in the activities of these enzymes was observed. Higher sucrose synthase activity (0.52 – 0.95 µmol sucrose min–1 mg–1 protein) was observed during the initial stages (S1 and S2) of flower bud development, in contrast to invertases. However, the lower activity (0.56 µmol sucrose min–1 mg–1 protein) of sucrose synthase at a later stage (S6) of senescence could help the mobilisation of vacuolar sucrose. The different isoforms of invertase exhibited variable levels of activity. Insoluble acid invertases (IAI) were the most active (11.01 µmol glucose min–1 mg–1 protein), followed by soluble acid invertases (SAI; 8.02 µmol glucose min–1 mg–1 protein), and soluble neutral invertases (SNI; 0.74 µmol glucose min–1 mg–1 protein) at Stage-4. A significant decline in invertase activities (IAI, 0.98; SAI, 1.25; SNI, 0.32 µmol glucose min–1 mg–1 protein) coincided with higher levels of ethylene production at the later stages (S5 and S6) of flower bud development and senescence. We propose that developmental as well as ethylene-mediated pathways account for petal senescence in rose.  相似文献   
28.
Rice is one of the most important crops in the world. The wild species of rice are expected to have novel beneficial alleles that have been lost from cultivated rice during the process of domestication. Therefore, wild species could be the potential source to induce lost genetic diversity in cultivated rice. Serving as an important reservoir of novel genes/QTLs, wild species, in general, are better adapted to different ecologies and can tolerate many biotic and abiotic stresses. Despite that, only a few wild species are studied and extensive characterization both at the molecular and morphological level is yet to be achieved. Several agronomically important genes/QTLs for improving biotic and abiotic stresses, resistance, productivity and grain quality traits were identified from AA genome donor wild species and were tagged with breeder friendly molecular markers for their transfer to elite genetic backgrounds. The present review provides information on the important wild rice species harbouring genes/QTLs for agriculturally important traits and their successful utilization in rice breeding programmes.  相似文献   
29.
30.
In the recent past, biochar and crop residues have attracted lots of attention as a viable strategy for maintaining soil health. This paper evaluates the comparative effect of two different doses (equivalent to 2 and 5 t C ha?1) of each of pine needle and Lantana biochar (PBC and LBC), wheat residue and lentil residue (WR and LR) on soil biological properties, nutrient availability and yield of rice and wheat in pot culture. Energy-dispersive X-ray spectroscopy (EDS) revealed higher C content of biochar than crop residues. Evaluation of biochemical quality reflected high recalcitrance indices of C and N for both PBC and LBC. Application of LBC and PBC increased the wheat grain yield significantly by 6.2%–24.2% over control. Both PBC and LBC significantly increased N and P uptakes in grain over the control and crop residues. Both biochars recorded a significant decrease of 33.9 and 71,7% in β-glucosidase activity in comparison to control at termination of study. PBC and LBC also resulted in more soil available N, P and K in soil at different intervals. The geometric mean of enzyme activities (GMea) reflected improved soil quality by PBC and LR and reduction by LBC application.  相似文献   
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