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11.
印楝杀虫剂防治蝗虫的应用前景 总被引:3,自引:0,他引:3
印楝杀虫剂是公认的最优秀的生物农药之一,在环境中无残留,对非靶标生物安全,对中华稻蝗(Oxyachinensis)、东亚飞蝗(Locusta migratoria manilensis)、黄脊竹蝗(Ceraoris kiangsu)、青脊竹蝗(Ceraoris nigricornis)、沙漠蝗(Schistocerca gregaria)、血黑蝗(Melanoplus sanguinipes)和泣黑背蝗(Eyprepocnermis plorclnS)等多种蝗虫具有优异的杀虫活性,并具有独特的杀虫作用机理,是防治蝗虫的理想药剂。 相似文献
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Qionglin Chen Xinlei Yu Shixia Liu Suya Luo Xiaojiao Chen Nianjun Xu Xue Sun 《Marine drugs》2022,20(7)
Agar is widely applied across the food, pharmaceutical and biotechnology industries, owing to its various bioactive functions. To better understand the agar biosynthesis in commercial seaweed Gracilariopsis lemaneiformis, the activities of four enzymes participating in the agar biosynthesis were detected, and phosphoglucomutase (PGM) was confirmed as highly correlated with agar accumulation. Three genes of PGM (GlPGM1, GlPGM2 and GlPGM3) were identified from the G. lemaneiformis genome. The subcellular localization analysis validated that GlPGM1 was located in the chloroplast and GlPGM3 was not significantly distributed in the organelles. Both the GlPGM1 and GlPGM3 protein levels showed a remarkable consistency with the agar variations, and GlPGM3 may participate in the carbon flux between (iso)floridoside, floridean starch and agar synthesis. After treatment with the PGM inhibitor, the agar and floridean starch contents and the activities of floridean starch synthase were significantly decreased; products identified in the Calvin cycle, the pentose phosphate pathway, the Embden-Meyerhof-Parnas pathway and the tricarboxylic acid cycle were depressed; however, lipids, phenolic acids and the intermediate metabolites, fructose-1,6-phosphate were upregulated. These findings reveal the essential role of PGM in regulating the carbon flux between agar and other carbohydrates in G. lemaneiformis, providing a guide for the artificial regulation of agar accumulation. 相似文献
14.
犬是人类的朋友,除了当作宠物,在现代社会,犬还是不可缺少的重要工作伙伴.2008年是英国首头警犬上路巡逻1 00周年,因此被英国指定为"2008援助犬年".英国邮政专为此于2008年2月5日发行<工作犬>邮票一套6枚,邮票图案选取现实生活中"有名有姓"的六种犬从事不同工作的场面,生动有趣.同时,这套邮票竟也是作为英国的2008年"欧罗巴(EUROPA)"邮票. 相似文献
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用带有鸡溶菌酶基因增强子(E)和启动子(P)的编码细菌氯霉素乙酰基转移酶(CAT)的融合基因(EPC),在其上游区、下游区或在上游和下游区同时插入鸡溶菌酶基因3'端核基质附着区(MAR)的不同表达载体MEPC、EPCM和MEPCM,稳定转染鸡HD11Promacrophage同源细胞系,筛选不同表达载体稳定整合后的细胞株,检测CAT表达水平,确定其表达基因拷贝数,从而分析鸡溶菌酶基因3'端MAR对基因表达的影响。稳定整合表达和瞬时表达实验结果表明,鸡溶菌酶基因3'端MAR在同源细胞系对基因表达没有激活作用,与该基因5'端MAR在同源或异源细胞系中能激活基因表达形成鲜明对照,说明5'瑞MAR和3'端MAR在调节鸡溶菌酶基因表达上存在一种协调关系。 相似文献
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采用基质栽培试验,研究对羟基苯甲酸、肉桂酸对3月生巨尾桉9号苗木生长及叶片抗氧化酶活性的影响,结果表明:对羟基苯甲酸各处理浓度(10、50、100、500 mg/L)下的苗高增长量、地径增长量均显著高于对照,且在10 mg/L时,苗高增长量最大,为52.33 cm;肉桂酸10 mg/L时巨尾桉苗木苗高增长量较对照高,且随着其浓度的增加,苗高增长量和地径增长量均逐渐降低。对羟基苯甲酸、肉桂酸各浓度下巨尾桉9号苗木叶片叶绿素总含量均极显著低于对照,丙二醛含量略高于对照;对羟基苯甲酸、肉桂酸各浓度对巨尾桉9号叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、多酚氧化酶(PPO)活性均具有一定的影响。对羟基苯甲酸10、50、100 mg/L及肉桂酸10 mg/L处理下的综合化感效应指数为正,对羟基苯甲酸500 mg/L及肉桂酸50、100、500 mg/L处理下的综合化感效应指数为负。可见,对羟基苯甲酸、肉桂酸对巨尾桉9号苗木的生长具有“低浓度促进、高浓度抑制”的规律,拐点浓度分别为100、10 mg/L;且在处理浓度相同时,肉桂酸的化感作用较对羟基苯甲酸强。 相似文献
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The role of ectomycorrhizal fungi in alleviating pine decline in semiarid sandy soil of northern China: an experimental approach 总被引:1,自引:0,他引:1
Jiao-jun Zhu Feng-qin Li Mei-ling Xu Hong-zhang Kang Xiang-yun Wu 《Annals of Forest Science》2008,65(3):304-304
The decline of Mongolian pine (Pinus sylvestris var. mongolica) trees on sandy land in northern China has caused serious ecological concerns. Mongolian pine is an ectomycorrhizal fungus (ECM)-dependent species. Three ECM species (Boletus sp., Lactarius deliciosus and L.sp.) were collected from Mongolian pine plantation stands to test their beneficial effects on Mongolian pine seedlings and their responses to environmental factors such as pH, drought stress and temperature. The results indicated that ECM inoculation significantly increased the rate of ECM colonization and the length of seedling shoots. The three ECM could grow in a pH range from 4 to 7, but did not grow under heavy drought stress (?1.53 MPa). High temperatures (over 37 °C) caused death of ECM. When related to soil pH, soil water content and temperature in the Mongolian pine plantations, water conditions and temperature were unfavorable for ECM growth in surface soil, but suitable in deeper soil. Therefore, it was concluded that the failure of natural regeneration in Mongolian pine plantations might be influenced by the lack of ECM in the surface soil because of high temperatures causing ECM death. Moreover, the majority of the root area is distributed in deeper soil, which alleviates the stresses on ECM development and arrests pine decline; this is beneficial for tree growth. 相似文献
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Cristina E. Almeida-Naranjo Patricio J. Espinoza-Montero Marcelo I. Muñoz-Rodríguez Cristina A. Villamar-Ayala 《Water, air, and soil pollution》2017,228(7):253
Hydraulic retention time (HRT) influence improving sludge flocculation with adding the polyelectrolytes (non-ionic, anionic, and cationic) was studied on an activated sludge (AS) system fed with synthetic domestic wastewater (SDW), dairy industry wastewater (DIW), and caramel industry wastewater (CIW). The sludge volumetric index, food/microorganism ratio (F/M), and mixed liquor volatile suspended solids at different HRTs (6, 8 and 10 h) were monitored on an experimental model. Results showed that both SDW and IW had the best sludge flocculation conditions at 8 h and 100 mL of non-ionic polyelectrolyte (0.2 mg L?1). In addition, this phenomenon reached the organic matter removal efficiencies of 95.9, 95.7, and 94.2% for SDW, DIW, and CIW, respectively. Therefore, optimum HRT increased the organic matter removal efficiencies by 10%, sludge concentration by 37% (22–55%), and F/M ratio by 70%. Moreover, the polyelectrolytes used in AS improved the sludge flocculation by 2.9 times. 相似文献