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1.
用8%胺鲜酯水剂在大白菜上进行田间药效试验,试验表明,在大白菜的大田返青期、生长期喷施,能有效地促进大白菜的生长,提高大白菜的产量。对大白菜中的维生素C和可溶性固形物含量等品质指标未发现有不良影响,且对品质有所提升。  相似文献   
2.
[目的]研究1.6%胺鲜酯对水稻生长和增产作用。[方法]在田间小区试验条件下,研究试验药剂不同使用剂量对水稻生长、增产效果和田间应用安全性。[结果]1.6%胺鲜酯水剂制剂稀释1000—1500倍,连续用药2次,水稻增产率达6.51%以上,与对照药剂相当,对环境和作物安全。[结论]1.6%胺鲜酯水剂是调节水稻生长性状和增产增效较为理想的药剂。  相似文献   
3.
本文介绍了农药中间体5-乙基吡啶-2,3-二甲酸二乙酯合成路线,通过试验分析,将生产过程中产生的废水进行回收,选择出适合工业化的清洁合成工艺,无三废,实现清洁合成。2步反应得到产品,总收率为70%(以乙氧基乙酸乙酯计),含量为85%。  相似文献   
4.
The interactions between six insecticides (indoxacarb, cypermethrin, chlorpyrifos, azinphosmethyl, tebufenozide and chlorfenapyr) and three potential synergists, (piperonyl butoxide (PBO), S,S,S-tributyl phosphorotrithioate (DEF) and diethyl maleate (DEM)) were studied by dietary exposure in a multi-resistant and a susceptible strain of the obliquebanded leafroller, Choristoneura rosaceana (Harris). The synergists did not produce appreciable synergism with most of the insecticides in the susceptible strain. Except for tebufenozide, PBO synergized all the insecticides to varying degrees in the resistant strain. A very high level of synergism by PBO was found with indoxacarb, which reduced the resistance level from 705- to 20-fold when PBO was administered alone and to around 10-fold when used in combination with DEF. DEF also synergized indoxacarb, cypermethrin, chlorpyrifos, azinphosmethyl and tebufenozide in the resistant strain. DEM produced synergism of indoxacarb, chlorpyrifos, azinphos-methyl and chlorfenapyr in the resistant strain. DEM was highly synergistic to cypermethrin, and to some extent to tebufenozide in both the susceptible and resistant strains equally, implying that detoxification by glutathione S-transferases was not a mechanism of resistance for these insecticides. The high level of synergism seen with DEM in the case of cypermethrin may be due to an increase in oxidative stress resulting from the removal of the antioxidant, glutathione. These studies indicate that enhanced detoxification, often mediated by cytochrome P-450 monooxygenases, but with probable esterase and glutathione S-transferase contributions in some cases, is the major mechanism imparting resistance to different insecticides in C. rosaceana.  相似文献   
5.
Peng F  Tao Q  Wu X  Dou H  Spencer S  Mang C  Xu L  Sun L  Zhao Y  Li H  Zeng S  Liu G  Hao X 《Fitoterapia》2012,83(3):568-585
Twenty-nine phenolic compounds were isolated from the root bark of fresh (Yunnan) ginger and their structures fully characterized. Selected compounds were divided into structural categories and twelve compounds subjected to in-vitro assays including DPPH radical scavenging, xanthine-oxidase inhibition, monoamine oxidase inhibition, rat-brain homogenate lipid peroxidation, and rat pheochromocytoma PC12 cell and primary liver cell viability to determine their antioxidant and cytoprotective properties. Isolated compounds were also tested against nine human tumor cell lines to characterize anticancer potency. Several diarylheptanoids and epoxidic diarylheptanoids were effective DPPH radical scavengers and moderately effective at inhibiting xanthine oxidase. An enone–dione analog of 6-shogaol (compound 2) was isolated and identified to be most effective at protecting PC12 cells from H2O2-induced damage. Almost all tested compounds inhibited lipid peroxidation. Three compounds, 6-shogaol, 10-gingerol and an enone-diarylheptanoid analog of curcumin (compound 6) were identified to be cytotoxic in cell lines tested, with KB and HL60 cells most susceptible to 6-shogaol and the curcumin analog with IC50 < 10 μM. QSAR analysis revealed cytotoxicity was related to compound lipophilicity and chemical reactivity. In conclusion, we observed distinct compounds in fresh ginger to have biological activities relevant in diseases associated with reactive oxygen species.  相似文献   
6.
文章以枸杞蚜虫为试虫,采用玻璃管药膜法研究了藿香精油的触杀剂量效应、藿香精油+马来酸二乙酯的触杀剂量效应、马来酸二乙酯对藿香精油的触杀毒力增效作用。结果表明,藿香精油在处理4 h后,精油最高剂量表现出的校正死亡率最高,是最低剂量校正死亡率的19.6倍。藿香精油对枸杞蚜虫的剂量效应为正比例关系。藿香精油+马来酸乙酯触杀枸杞蚜虫的触杀剂量在1 mL·L^-1下,最长处理时间的枸杞蚜虫死亡数是最低处理时间的10.4倍。马来酸二乙酯(增效剂)+藿香精油对枸杞蚜虫的剂量效应为正比例关系。藿香精油对枸杞蚜虫触杀4 h后,枸杞蚜虫的LC50为3.17 mL·L^-1,含有马来酸二乙酯的藿香精油对枸杞蚜虫的LC50为1.09 mL·L^-1。枸杞蚜虫对含有增效剂的藿香精油的触杀处理更敏感。两者的95%置信限覆盖率为0,表明两者对枸杞蚜虫的触杀毒力存在极显著差异。0.02%马来酸二乙酯的增效比为2.90,证明其对藿香精油具有增效作用。  相似文献   
7.
Intrinsic activities of monodisperse ethoxylated dodecanols (MEDs), diethyl suberate (DESU) and tributyl phosphate (TBP) were investigated using Stephanotis floribunda leaf cuticular membranes (CMs) and [14C]2,4‐dichlorophenoxy butyric acid (2,4‐DB) as a model solute. When sorbed in cuticular membranes, MEDs, DESU and TBP increase solute mobility and are called accelerators for this reason. With MEDs, dose‐effect curves (log mobility vs accelerator concentration) were linear but, with DESU and TBP, curves convex to the x axes were obtained that approached a maximum at 90 and 150 g kg−1, respectively. Accelerators increased the mobility of 2,4‐DB in the CMs by 9‐ to 48‐fold, and effects were larger at lower temperatures (range 15–30 °C). Activation energy for diffusion of 2,4‐DB was 105 kJ mol−1, decreasing with increasing accelerator concentrations to 26 kJ mol−1 with DESU at 90 g kg−1 and 64 kJ mol−1 with TBP at 150 g kg−1. Thus, the intrinsic activity of DESU was much higher than that of TBP, which implies that, for a given effect, less DESU than TBP would be needed. MEDs were also very effective accelerators, lowering activation energies to 36 kJ mol−1. Data are discussed in relation to increasing rates of foliar penetration of active ingredients at low temperatures. © 2001 Society of Chemical Industry  相似文献   
8.
以云烟87为材料,研究8%胺鲜酯(DA–6)(质量浓度15.0、10.0、5.0μg/L)与10.0 mmol/L氯化钙配施对烤烟育苗的影响。结果表明:与清水对照相比,播种7d和15d后配施处理的烤烟出苗率分别提高4.50%~10.40%、2.74%~8.33%,成苗率提高3.19%~8.81%;成苗期的苗高、茎基宽、最大叶叶面积分别提高了5.99%~17.66%、1.29%~5.47%、21.1%~73.6%;根、茎、叶、全苗干物质积累量分别提高了25.0%~55.0%、16.7%~33.3%、14.1%~33.8%、16.5%~36.9%,根冠比提高了9.1%~17.0%;配施处理的叶片叶绿素(叶绿素a+叶绿素b)含量增加26.0%~64.9%;配施处理硝酸还原酶活性提高了52.1%~95.9%;过氧化氢酶(CAT)活性、过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量分别降低了41.5%~59.3%、27.9%~62.9%、30.3%~81.1%和34.0%~63.7%,表明用10μg/L DA–6+10 mmol/L氯化钙配施浸种效果最佳。  相似文献   
9.
采前喷施胺鲜酯对采后龙眼果实品质和耐贮性的影响   总被引:3,自引:0,他引:3  
研究采前喷施胺鲜酯对采后龙眼果实品质和耐贮性的影响,为龙眼果实贮藏保鲜提供科学依据和生产指导。以‘福眼’龙眼为材料,在龙眼盛花期后70、90、110 d用浓度为10 mg/kg的胺鲜酯喷施龙眼果实3次,以蒸馏水喷施为对照。龙眼果实在盛花期后120 d采收,采后龙眼果实经过挑选、清洗和晾干后用0.015 mm厚的聚乙烯薄膜袋密封包装,在(28±1)℃、相对湿度85%下贮藏。贮藏期间取样测定果实呼吸强度、果皮色素含量、果肉营养物质含量和果实耐贮性指标。结果表明:与对照龙眼果实对比,采前喷施胺鲜酯可有效降低采后贮藏期间龙眼果实呼吸强度,保持较高的果皮叶绿素、类胡萝卜素、花色素苷和类黄酮含量,及较高的果肉TSS、可溶性总糖、蔗糖和维生素C含量,延缓果皮褐变和果肉自溶的发生,降低果实失重率,保持较高的好果率。因此认为,采前喷施浓度为10 mg/kg的胺鲜酯能有效延缓采后龙眼果实的品质下降、较好维持龙眼果实品质,提高龙眼果实耐贮性和保鲜效果。  相似文献   
10.
不同生根剂对含笑扦插繁殖的生根效果分析   总被引:3,自引:0,他引:3  
将根太阳生根剂、ABT1号生根粉、NAA、IBA、丰叶宝5种生根剂应用于含笑扦插育苗,对比试验结果表明,根太阳生根剂较其他常用生根剂能促进插穗提早9~21d生根,比清水对照早30d;插穗平均生根率高达91.67%,比其他生根剂提高了12.67~45.67个百分点,比对照提高67.7个百分点;每插穗平均生根量为11.8条,比其他生根剂和对照提高3.7~8.5条,植株整体表现优良。  相似文献   
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