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11.
Tomatoes are consumed and cultivated all over the world for not only their pleasant taste but also their curative properties. Therefore, the challenge for growers is to obtain high-quality crop productions by developing new varieties of tomatoes or new ecofriendly fertilizers. This study was to test a bone glue-based foliar fertilizer on the tomato crop. The experiment was organized in a vegetation house under an original treatment scheme. Four types of foliar fertilizers were tested: macroelements, microelements and glue; macroelements and glue; microeleements and glue; and macroelements and microelements without glue. The fertilizers were applied as diluted solutions (0.5% and 1%) across three treatments applied on nine variants. The treatments with bone glue-based foliar fertilizer led to a high-quality production of healthy tomatoes, a good absorption of nutrients together with a reduced nitrites level in tomatoes and an increase of agricultural productivity. The applied foliar fertilizers tested on the hybrid tomatoes used in the experiment had a significant positive influence on vegetative growth. The nitrate concentration in the fruit did not exceed the maximum accepted level. The agronomic analysis of the mineral composition of the fruit revealed that foliar fertilizers with glue significantly influenced nutrient assimilation during the treatments. The level of nitrogen (N), phosphorus (P), and potassium (K) recovery following the application of bone glue foliar fertilizers was higher as compared to the control and the variant without bone glue. Biometric measurements had shown significant differences favorable to tomatoes treated with this bone glue foliar fertilizer.  相似文献   
12.
The paper deals with the spatial distribution of root density in highbush blueberry plantations of various ages for a proper planting distance recommendation and a better irrigation and fertilization management. The environmental conditions consist of sandy-loamy soils and a continental temperate climate. Two highbush blueberry cultivars were studied, ‘Bluecrop’ and ‘Blueray’. Root density (RD) and density of root cross-sectional area (RCSA) were investigated for various root diameters. It was found that the prevalent type of roots in highbush blueberry crops is the hair type, with root diameters less than 0.1?mm. Both RD and RCSA decreased with distance from plant and with soil depth; the 38-year-old crop showed a more developed root system versus the 8?year-old crop. In both cases the roots did not grow more than 0.6?m laterally and more than 0.7?m deep. According to these results, the planting distances in highbush blueberry could be reduced to substantially increase the number of plants/ha and fruit yield. Irrigation application should be carried out to wet a proper soil volume, about 0.6–0.7?m deep for older crops, and about 0.5?m deep for younger crops.  相似文献   
13.
14.
Recent plant diversity changes on Europe's mountain summits   总被引:2,自引:0,他引:2  
In mountainous regions, climate warming is expected to shift species' ranges to higher altitudes. Evidence for such shifts is still mostly from revisitations of historical sites. We present recent (2001 to 2008) changes in vascular plant species richness observed in a standardized monitoring network across Europe's major mountain ranges. Species have moved upslope on average. However, these shifts had opposite effects on the summit floras' species richness in boreal-temperate mountain regions (+3.9 species on average) and Mediterranean mountain regions (-1.4 species), probably because recent climatic trends have decreased the availability of water in the European south. Because Mediterranean mountains are particularly rich in endemic species, a continuation of these trends might shrink the European mountain flora, despite an average increase in summit species richness across the region.  相似文献   
15.
In this study, we have analyzed 23 PCV2 ORF2 sequences recovered from wild boar population in Romania. The PCV2 sequences were originated from different geographical regions in Romania, and collected between 2008 and 2009 during the classical swine fever virus (CSFV) surveillance campaign. Complete open reading frame 2 (ORF2) nucleotide sequences were obtained and compared with sequences mainly from European and Asian isolates. The Romanian sequences were identified as belonging to previously described clusters 2a and 2b, with high degree of heterogeneity (PCV2 ORF2 nucleotide homology ranged between 90.1% and 100%). Interestingly, for cluster 2a, the majority of the sequences (8 from a total number of 9) clustered mainly with the Asian isolates (especially China, but also India and South Korea), with three exceptions from Europe previously reported in Germany, Belgium and The Netherlands.  相似文献   
16.

• Introduction  

The study of phenotypic and genetic differentiation between incipient species or species that have recently diverged provides insights into the evolutionary history of species complexes and may contribute to our understanding of how species will evolve in contrasting environmental conditions.  相似文献   
17.
A 10‐wk feeding experiment was conducted to evaluate the potential use of fermented soybean curd residues (FSCR) as an energy source in diets for juvenile olive flounder, Paralichthys olivaceus. Five isonitrogenous and isoenergetic diets were formulated to contain dry soybean curd residues to replace wheat meal (WM) at the levels of 0, 25, 50, 75, and 100% (FSCR0, FSCR25, FSCR50, FSCR75, and FSCR100, respectively). Fish averaging 6.00 ± 0.07 g (mean ± SD) were randomly distributed into 15 aquaria as groups of 15 fish and fed the experimental diets in triplicate at a rate of 4–5% of wet body weight per day twice daily on dry matter basis. At the conclusion of the feeding trial, weight gain (WG) and specific growth rate (SGR) of fish fed diet FSCR25 were significantly higher than those of fish fed diets FSCR50, FSCR75, and FSCR100 (P < 0.05); however, there were no significant differences in WG and SGR among fish fed diets FSCR0 and FSCR25 and among those fed diets FSCR0 and FSCR50. Feed efficiency and protein efficiency ratio of olive flounder fed diet FSCR25 were significantly higher than those of fish fed diets FSCR50, FSCR75, and FSCR100 (P < 0.05); however, there were no significant differences in these parameters among fish fed diets FSCR0 and FSCR25 and among those fed diets FSCR0, FSCR50, FSCR75, and FSCR100. Hematological characteristics, condition factor, hepatosomatic index, and survival rate of fish fed FSCR0 were not significantly different from those of fish fed the other diets. These results indicated that FSCR could replace up to 50% WM as an energy source in juvenile olive flounder diets based on ANOVA test.  相似文献   
18.
The profile of glucosinolates in relation to the antioxidant capacity of five Brassica vegetables (Broccoli, Cauliflower, Kohlrabi, White and Red Cabbage) grown by organic and conventional agricultural practices in Transylvania region-Romania, were determined and compared. The qualitative and quantitative compositions of glucosinolates were determined by HPLC-PDA technique. The antioxidant capacity was comparatively determined by ABTS, DPPH, FRAP and Folin-Ciocalteu assays. The highest glucosinolates levels were found in the Broccoli samples grown under conventional practices (14.24 μmol/g dry weight), glucoraphanin, glucobrassicin and neo-glucobrassicin being the major components. The total glucosinolates content was similar in Kohlrabi and Cauliflower (4.89 and 4.84 μmol/g dry weight, respectively), the indolyl glucosinolates were predominant in Kohlrabi, while the aliphatic derivatives (sinigrin and glucoiberin) were major in Cauliflower. In Cabbage samples, the aliphatic glucosinolates were predominat against indolyl derivatives, glucoraphanin and glucoiberin being the main ones in Red Cabbage. The principal component analysis was applied to discriminate among conventional and organic samples and demonstrated non-overlaps between these two agricultural practices. Meanwhile it was shown that glucosinolates may represent appropriate molecular markers of Brassica vegetables, their antioxidant capacity being higher in organic crops, without significant differences among different Brassica varieties.  相似文献   
19.
Initial adherence to host cells is the first step of the infection of enteropathogenic Escherichia coli (EPEC), enterohaemorrhagic Escherichia coli (EHEC) and verotoxigenic Escherichia coli (VTEC) strains. The importance of this step in the infection resides in the fact that (1) adherence is the first contact between bacteria and intestinal cells without which the other steps cannot occur and (2) adherence is the basis of host specificity for a lot of pathogens. This review describes the initial adhesins of the EPEC, EHEC and VTEC strains. During the last few years, several new adhesins and putative colonisation factors have been described, especially in EHEC strains. Only a few adhesins (BfpA, AF/R1, AF/R2, Ral, F18 adhesins) appear to be host and pathotype specific. The others are found in more than one species and/or pathotype (EPEC, EHEC, VTEC). Initial adherence of EPEC, EHEC and VTEC strains to host cells is probably mediated by multiple mechanisms.  相似文献   
20.
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