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41.
Legesse Negash 《Agroforestry Systems》2002,56(1):39-46
Erythrina brucei Schweinf. emend. Gillett (Papilionaceae),a tree species that is endemic to Ethiopia, is known to possess useful agroforestry attributes, but these attributes have not been quantified. To achieve this, propagation of the species, growth rate of young trees and their impact on barley (Hordeum vulgare L.), and leaf-nutrient concentrations were examined. Germination of seeds planted in plastic pots varied from 73 to 93%, and direct seeding in the field yielded 83%germination. Branch cuttings obtained from 2 to 3-year-old stock plants (n =150) resulted in 70 to 80% rooting within 8 to 12 weeks after setting cuttings into the rooting medium. Considerable nodulation occurred on leaves one year after planting out seedlings and stecklings. Leaf concentrations of Mg, N,P, and S were significantly lower in nodulated than in the non-nodulated leaves. On the other hand, leaf Fe concentration was higher in nodulated than in the non-nodulated leaves. There was no significant difference in Ca and K contentsbetween the nodulated and non-nodulated leaves. E. brucei-treatment significantly increased tiller and seed numbers, as well as seed weight. However, thousand-grain weight and grain size were similar in harvests from E. brucei-treated and the control plots. The results indicate that the species is easy to propagate by seed and vegetative means, grows fast, is desirable for intercropping, and has relatively high leaf-nutrient concentration.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
42.
HPLC-PDAD法检测3种中兽药散剂中违规添加4种喹诺酮类药物的研究 总被引:1,自引:1,他引:0
为了建立检测中兽药散剂中违规添加氧氟沙星、诺氟沙星、环丙沙星、恩诺沙星4种喹诺酮类药物的反相高效液相色谱法(HPLC-PDAD),采用Atlantis T3(十八烷基硅烷键合硅胶.4.6min×250mm,5μm)色谱柱,流动相为磷酸溶液:乙腈:甲醇(85.5:7.0:7.5),流速为1.0mL/min。检测波长为283nm。4种喹诺酮类药物检查方法的线性关系良好,r〉0.9999;回收率均在98.4%~104.6%范围内,RSD均在0.9%~2.3%之间;4种喹诺酮类药物在肥猪散、健胃散、银翘散3种中兽药散剂中的检出限均为200mg/kg。该方法可用于中兽药散剂中违规添加喹诺酮类药物的检测。 相似文献
43.
文章分析传统岭南庭园的造园艺术在当代热带庭园设计中的运用和发展,重点对空间渗透交流、视线与空间序列、花木营造等方面进行分析,找寻其中的历史情结,以期为中国当代热带庭园的传承与创新提供一些参考。 相似文献
44.
Imorou Toko Emile D. Fiogbe Patrick Kestemont 《Aquaculture (Amsterdam, Netherlands)》2007,262(1):65-72
African catfish (Clarias gariepinus) (initial body weight: 34.8 ± 4.8 g) and vundu catfish (Heterobranchus longifilis) (initial body weight: 39.1 ± 8.2 g) fingerlings were stocked at densities of 4, 6 or 8 fish m− 3 in traditional fish ponds (whedos) constructed in the floodplain of the Oueme River (South Benin, West Africa), for 70 days from March to June 2005. Fish were fed twice a day with 34% crude protein feed formulated with locally available ingredients. The effects of stocking density were evaluated in growth responses, gross production and body composition. Water quality variables were similar (p > 0.05) in all compartments. Temperature and pH were at the optimum level for fish. Dissolved oxygen ranged from 0.9 to 1.2 mg l− 1 during the experiment and secchi disc transparency was low (< 14 cm). In both species, growth responses increased with the increasing density, significantly in African catfish stocked at density of 8 fish m− 3 compared to the other densities (4 and 6 fish m− 3) but not significantly in vundu catfish. Production data ranged from 3.1 ± 0.5 to 22.8 ± 4.5 t ha− 1 year− 1 in African catfish and from 6.1 ± 1.2 to 15.1 ± 3.1 t ha− 1 year− 1 in vundu catfish. Production increased with increasing stocking densities but only significantly (p < 0.05) between the density of 8 fish m− 3 and the other densities. In both species, carcass fat increased with increasing density (p < 0.05) while carcass protein and moisture decreased (p > 0.05). These results are important because they indicate that, as far as growth rate and production are concerned, African catfish is more profitable than vundu catfish for culture at high density in whedo. 相似文献
45.
46.
对传统中国农业发展研究中的“人口论”和“制度论”进行了分析,认为有其合理性,但也存在一定不足。尽管有人口压力,传统中国的农业技术一直保持在一个较高的水平。在没有农业以外部门的科学技术的突破与发展的背景下,传统中国农业技术的发展长期陷在“高水平的陷阱”中。因此,笔者认为,在解释传统中国农业技术发展滞后的社会原因时,应注意“传统”与“现代”农业技术的分野。 相似文献
47.
6,7-Dimethylesculetin (D), geniposide (G) and rhein (R) are the three major active ingredients of Yin-Chen-Hao-Tang (YCHT), a famous Chinese herbal formula, which has been shown to be clinically effective for treating hepatic injury (HI) syndrome. The present study was conducted to investigate the therapeutic and synergistic effects of COC (combination of D, G and R) on HI rats by combining pharmacokinetic with biochemical analysis strategy. Plasma was analyzed by using reversed-phase high performance liquid chromatography (RP-HPLC). Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) models were built to evaluate the therapeutic and synergistic effects of COC at the biochemical level. Here, we report that the COC combination could increase the plasma level, slow elimination rate, exert a more robust therapeutic effect than any one or two of the three individual compounds by hitting multiple targets in a rat model of HI. Overall, this beneficially accounts for the popular view that traditional Chinese medicine (TCM) formula usually takes multi-component to exert their therapeutic effects. We suggest that dissecting the mode of action of clinically effective formula to be capable of producing a sufficient effect at low doses. 相似文献
48.
I. S. Bisht K. S. Rao D. C. Bhandari Sunil Nautiyal R. K. Maikhuri B. S. Dhillon 《Genetic Resources and Crop Evolution》2006,53(7):1333-1350
There is a growing realisation world over that the introduction of modern agriculture has to be supplemented with measures
to conserve biodiversity in situ if yield gains are to be stabilized. Hence, there is a growing interest from agricultural development specialists and conservation
biologists for understanding the socioeconomic factors determining the conservation of biodiversity in situ. The present study was conducted with the objective of understanding the in situ (on-farm) conservation of agrobiodiversity in traditional agroecosystems taking the Urgam valley in north-western Himalaya
of India, as a case study. An inventory was made of traditional crops and wild economic species for subsistence, and the structure
of forest resource base, traditional knowledge related to resource management and use. Institutional and scientific challenges
for in situ (on-farm) management of crop diversity were studied and are discussed in this paper. Complementarity of in situ (on-farm) conservation with ex situ conservation together with crop improvement in such marginal areas are suggested. 相似文献
49.
介绍了研究型图书馆的特点和比较传统型图书馆和研究型图书馆,分析了我国科研院所图书馆向研究型图书馆发展的必要性,提出科研院所图书馆由传统服务向研究型发展的对策。
相似文献50.