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51.
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53.
LING Yun-biao XU Rui-yun QIU Wan-shou CHU Zhong-hua YANG Hong-zhi TAN Zhi OU Qing-jia 《园艺学报》2003,19(12):1649-1652
AIM: To investigate the effect of Chinese herbs, Ganxianfang(GXF), on rat hepatic stellate cells (HSC) proliferation and collagen synthesis. METHODS: Two types of herb serum, portal venous serum and circumferential venous serum, were prepared from rats infused intragastrically with 16, 8, 4 times adult dose of GXF decoction. HSC isolated from rat liver were processed with the above sera in vitro. Then we mensurated the radioactivity of HSC admixed with [[3H]H]proline and [[3H]H]thymine to judge the effect on proliferation and collagen synthesis of HSC. RESULTS: Both two types of serum collected 0.5, 1, 2 h after intragastrical infusion inhibited HSC proliferation (P<0.05), and the serum collected 1 h after intragastrical infusion had the strongest effect (P<0.05). Portal serum decreasea collagen synthesis (P<0.05), but circumferential serum had no effect (P>0.05). CONCLUSION: Inhibition of HSC proliferation and decrease of collagen synthesis may contribute to the GXF antifibrotic action. 相似文献
54.
Effects of aqueous extracts and decomposition of Mikania micrantha H.B.K.
debris on selected agronomic crops 总被引:2,自引:0,他引:2
Laboratory and greenhouse experiments were conducted to determine the effects of aqueous extract and the debris of Mile-a-Minute ( Mikania micrantha H.B.K.) on the germination and growth of four test species, viz. tomato ( Lycopersicon esculentum Mill.), Chinese cabbage ( Brassica chinensis L.), corn ( Zea mays L.) and long bean ( Vigna sesquipedalis L.). Germination percentage, radicle length and fresh weight of two crops, Chinese cabbage and tomato, decreased progressively when plants were exposed to increasing concentrations (12.5, 25, 37.5 and 50 g L−1 ) of aqueous extract of Mikania , but did not affect those of corn and long bean seedlings. The emergence of tomato and Chinese cabbage was greatly reduced when Mikania debris was incorporated into the soil, irrespective of the amount of debris and the decomposition period. In contrast, the emergence of corn and long bean seedlings was not affected. The application of fertilizer (NPK 15 : 15 : 15) enhanced the fresh weight of all seedlings tested as compared with those not supplied with the fertilizer. Four compounds were identified in the leaf extract of Mikania , viz. caffeic acid, p -hydroxybenzaldehyde, resorcinol and vanillic acid. 相似文献
55.
荔枝、龙眼园使用机油乳剂的安全性及其对荔枝蒂蛀虫的防治研究 总被引:8,自引:0,他引:8
利用机油乳剂对果树进行安全性和防治荔枝蒂蛀虫Conopomorpha sinensis Bradley研究试验,结果表明,喷施机油乳剂后荔枝和龙眼的落果率与对照树4无差异,喷清水的对照树其蒂蛀虫蛀果率比喷机油乳剂的处理树高,分别为150、200和250倍机油乳剂处理的2.8、3.0和2.7倍。在荔枝、龙眼园应用机油乳剂防治害虫不会导致落叶、落果、畸形叶和畸形果,也不会延缓果实的生长和成熟及降低单果重,而有利于控制介壳虫、螨类、蛀果类等害虫。机油乳剂可替代广谱性化学农药的使用,减少化学农药的污染,有利于果园天敌的生存、繁殖,提高生物多样性,改善果园生态环境。 相似文献
56.
甜菜夜蛾性信息素组分的鉴定及其田间试验 总被引:8,自引:0,他引:8
采用气相色谱仪(GC)及气质联用仪(GC-MS)等技术对我国甜菜夜蛾性信息素组分的鉴定结果表明,雌蛾性信息素腺体中含有4种组分,分别为Z9,E12-14:Ac(A)、Z9-14:OH(B)、Z9-14:Ac(C)和Z9,E12-14:OH(D);田间和室内种群各组分的比例(A:B:C:D)分别为47:18:18:17和43:18:23:16,比例及滴度在两种群间未有显著差异;雄蛾田间引诱测定表明,组分A、B显示性信息素活性。几种不同配比的硅橡胶塞诱芯在田间均显示极高的诱蛾活性,以9:1的AB二元诱芯(剂量100μg)最高,其诱蛾量与黑光灯相当,两者呈显著的正相关性,表明该诱芯可替代黑光灯用于甜菜夜蛾的种群测报。利用性诱捕器进行田间种群监测显示,1999年浙江省慈溪市的甜菜夜蛾共发生6代,以第4、5代发生量最高。 相似文献
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59.
Pest Management in Traditional Tropical Agroecosystems: Lessons for Pest Prevention Research and Extension 总被引:1,自引:0,他引:1
Helda Morales 《Integrated Pest Management Reviews》2002,7(3):145-163
Based on current agroecological theory and IPM practices, this review explores the role of traditional practices, involving
site selection, soil management, timing of planting and harvesting, crop resistance, intercropping, weed management, harvest
residue management, post-harvest management, natural enemies management, mechanical control, repellents and traps in the natural
regulation of potential pests. In synthesis, the literature suggests that although pest management professionals focus their
efforts on pest control, the preventative approach taken by traditional farmers is more effective. Potential constraints to
the implementation of this preventive pest management approach include:(1) lack of integration of ecological theory and pest
management, (2) lack of cooperation among social and biological scientists, and (3) lack of real efforts to work with farmers
as equals and support mechanisms that protect their knowledge.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
60.
Denis J. Sonwa Ousmane Coulibaly A. Akinwumi Adesina Stephan F. Weise Mathurin Tchatat 《Integrated Pest Management Reviews》2002,7(3):191-199
Imports of pesticides have long been subsidised for use in the cocoa agroforests of the humid forest zone of southern Cameroon.
With the liberalisation of the cocoa and pesticides sectors and the devaluation of the local currency (CFA franc), farmers
are facing fluctuations in the price paid for cocoa and the high cost of farm inputs. Without the support of the extension
services, they themselves have developed traditional integrated control methods based on the use of plant extracts mixed with
conventional pesticides. From a survey of 300 cocoa farmers, the study assesses the farmers' command of these methods, the
pests controlled, the problems encountered and the institutional constraints in the definition and dissemination of integrated
control methods. The study concludes with recommendations for research and development towards the better definition and dissemination
of integrated control methods.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献