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1.
Protoporphyrinogen oxidase inhibitor has become the focus research field as herbicides.Seven novel N-benzoxazolonyluracils were obtained by cyclization of 6-aminobenzoxazolone derivatives with ethyl 3-dimethylcarbamoylamido-4,4,4-trifluorocrotonate and then methylation or amination, and the reaction yields were between 59%-86%. The chemical structures of the compounds were identified by Elemental Analysis, MS and ^1H NMR. Biological results indicate that some compounds exhibit excellent control of broadleaf weeds at post-emergence by low dosage 18.75 ga.i/ha, but are not effective for grass weeds below dosage 37.5 ga. i/ha. In addition, these compounds show no damage at high-dosage 150 ga. i/ha to wheat and corn, but are unsafe to dicotyledonous plants such as cole, soybean and sorghum even at lower dosage 18.75 ga. i/ha.  相似文献   

2.
A newly isolated strain EL31410, producing elastase (E.C3.4.4.7) with high elastolytic activity was identified as Bacillus sp. In the medium optimization, it was found that wheat bran and soybean flour hydrosate were the best crude carbon and nitrogen source for enzyme production, respectively. Addition of corn steep flour can affect the bacterium growth and elastase production. A fractional factorial design was applied to study the main factors that affect the enzyme production, and central composite experimental design and response surface methodology were adopted to derive a statistical model for the effect of wheat bran and soybean flour hydrosate on elastase production. The experimental results showed that wheat bran had positive effect but soybean flour hydrosate had negative effect, on enzyme production. An initial concentration of 3.4%(w/v) wheat bran and 9.4%(v/v) soybean flour hydrosate were found to be optimal for enzyme production in batch culture. The time course of elastase production in the optimized medium composition was also described.  相似文献   

3.
A newly isolated strain EL31410, producing elastase (E. C3. 4. 4. 7) with high elastolytic activity was identified asBacillus sp. In the medium optimization, it was found that wheat bran and soybean flour hydrosate were the best crude carbon and nitrogen source for enzyme production, respectively. Addition of corn steep flour can affect the bacterium growth and elastase production. A fractional factorial design was applied to study the main factors that affect the enzyme production, and central composite experimental design and response surface methodology were adopted to derive a statistical model for the effect of wheat bran and soybean flour hydrosate on elastase production. The experimental results showed that wheat bran had positive effect but soybean flour hydrosate had negative effect, on enzyme production. An initial concentration of 3.4% (w/v) wheat bran and 9.4% (v/v) soybean flour hydrosate were found to be optimal for enzyme production in batch culture. The time course of elastase production in the optimized medium composition was also described. Project (No. 300024) supported by the Zhejiang Provincial Natural Science Foundation of China  相似文献   

4.
ＩＮＴＲＯＤＵＣＴＩＯＮＡｎｉｎｃｒｅａｓｉｎｇｄｅｍａｎｄｆｒｏｍｃｏｎｓｕｍｅｒｓｆｏｒｈｅａｌｔｈｙａｎｄｌｏｗｃｏｓｔｍｅｄｉｃａｌｓｈａｓｌｅｄｔｏｔｈｅｄｅ ｖｅｌｏｐｍｅｎｔｏｆａｌｔｅｒｎａｔｉｖｅｍｅｄｉｃａｌｔｈｅｒａｐｙａｇｅｎｔｓｕ  相似文献   

5.
目的:分析CYP81A6基因在苯达松及甲磺隆处理下的诱导表达模式,解释该基因与两种除草剂代谢相关的可能原因。创新点:从两种除草剂降解途径中产生的小分子物质的结构相似性出发,通过基因诱导表达的特点分析,解释CYP81A6和两种除草剂降解相关的原因。方法:通过实时定量聚合酶链反应(PCR)来分析基因表达的特点;利用CYP81A6启动子与GUS报告基因构建的载体来分析组织特异性表达;通过亚细胞定位来确定CYP81A6发挥功能的场所。结论:CYP81A6基因受苯达松及甲磺隆诱导,在不同的时间点开始上调,说明了甲磺隆的降解中间产物可以诱导这个基因的表达;CYP81A6是组成型表达,在根、茎、叶中均有表达;亚细胞定位结果证明CYP81A6是一个内质网上的蛋白。  相似文献   

6.
Pleurotus sajor-caju (Fr.) Singer was cultivated on selected agro wastes viz. cotton stalks, groundnut haulms, soybean straw, pigeon pea stalks and leaves and wheat straw, alone or in combinations. Cotton stalks, pigeon pea stalks and wheat straw alone or in combination were found to be more suitable than groundnut haulms and soybean straw for the cultivation. Organic supplements such as groundnut oilseed cake, gram powder and rice bran not only affected growth parameters but also increased yields. Thus bioconversion of lignocellulosic biomass by P. sajor-caju offers a promising way to convert low quality biomass into an improved human food.  相似文献   

7.
A pot culture experiment was carried out to investigate the accumulation properties of mercury (Hg) in rice grain and cabbage grown in seven soil types (Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols) spiked with different concentrations of Hg (CK, 0.25, 0.50, 1.00, 2.00, and 4.00 mg/kg). The results of this study showed that Hg accumulation of plants was significantly affected by soil types. Hg concentration in both rice grain and cabbage increased with soil Hg concentrations, but this increase differed among the seven soils. The stepwise multiple regression analysis showed that pH, Mn(II), particle size distribution, and cation exchange capacity have a close relationship with Hg accumulation in plants, which suggested that physicochemical characteristics of soils can affect the Hg accumulation in rice grain and cabbage. Critical Hg concentrations in seven soils were identified for rice grain and cabbage based on the maximum safe level for daily intake of Hg, dietary habits of the population, and Hg accumulation in plants grown in different soil types. Soil Hg limits for rice grain in Udic Ferrisols, Mollisol, Periudic Argosols, Latosol, Ustic Cambosols, Calcaric Regosols, and Stagnic Anthrosols were 1.10, 2.00, 2.60, 2.78, 1.53, 0.63, and 2.17 mg/kg, respectively, and critical soil Hg levels for cabbage are 0.27, 1.35, 1.80, 1.70, 0.69, 1.68, and 2.60 mg/kg, respectively.  相似文献   

8.
用粉渣代替部分粮食喂肥育猪。试验用 30千克左右的长白杂交猪 2 0头 ,分成试验和对照组 ,每组 1 0头 ,公母各半 ,试验组饲喂用粉渣代替部分粮食的自配饲料 ,而对照组饲喂常规配合饲料。结果表明试验组与对照组净增重、日增重和日耗料无显著差异 ,而试验组的日支出低于对照组的 ,日增收高于对照组的。暗示粉渣可代替部分粮食喂猪  相似文献   

9.
INTRODUCTION Pencycuron [1-(4-chlorobenzyl)-1-cyclopentyl- 3-phenylurea], a relatively new non-systemic protec-tive fungicide for controlling sheath blight (Rhizoc-tonia solani) of rice (Sylvanie and Cornis, 1989; Tomlin, 1997), is expected to be used widely in ag-ricultural production particularly in Asia. However, information on the dissipation pattern of pencycuron in rice plant is lacking. Little information on the en-vironmental fate of pencycuron has been published although there …  相似文献   

10.
叶绿体结构与功能以及相应叶片光合作用能力会都会受到除草剂的影响.植物叶绿体光系统II（PSII）被认为是光诱导延迟荧光（DF）的最主要的产生位点.以京黄3号大豆品种为测试植物,利用自行研制的便携式延迟荧光检测系统,研究了三种功能已知除草剂对DF衰减动力学曲线的影响.结果表明,通过解析延迟荧光衰减动力学曲线,发现延迟荧光衰减双指数数理解析式的变化能准确、真实的反应不同除草剂光合电子传递链的作用机制和作用位点.因此,延迟荧光衰减动力学可为除草剂药理分析、作物光合代谢损伤诊断以及新一代除草剂开发提供一实用、无损的新方法.  相似文献   

11.
The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels （0.97 and 18.2 dS/m） and four levels of plant residues （control, alfalfa, wheat and corn） with three replications was performed. A first order kinetic model was used to describe the C mineralization and to calculate the potentially mineralizable C. The CO2-C evolved under non-saline condition, ranged from 814.6 to 4842.4 mg CO2-C/kg in control and alfalfa residue-amended soils, respectively. Salinization reduced the rates of CO2 evolution by 18.7%, 6.2% and 5.2% in alfalfa, wheat and corn residue-amended soils, respectively. Potentially mineralizable C （Co） was reduced significantly in salinized alfalfa residue-treated soils whereas, no significant difference was observed for control treatments as well as wheat and corn residue-treated soils. We concluded that the response pattern of C mineralization to salinity stress depended on the plant residue quality and duration of incubation.  相似文献   

12.
进行了春雷霉素防治水稻稻瘟病试验,试验结果表明,2％春雷霉素WP对水稻稻穗瘟有较好的防效,防效达91．0％-94．2％,试验剂量下对水稻安全无害,可以大面积推广应用,生产上推荐用量为112．45—181．25g／hm^2。  相似文献   

13.
本文对甲乙酮的市场、技术及发展前景等方面进行了较为全面的分析，认为甲乙酮在我国是有市场的，从我国甲乙酮生产和消费的现状来看建设该项目也是可行的。  相似文献   

14.
通过盆栽试验,研究了不同土壤条件对4个蕹菜Cd积累典型品种的种子萌发和生长特性的影响．结果显示品种和土壤对发芽率、株高和生物量的效应均极显著（P〈0．01）．各品种种子平均发芽率依次为T308〉QLB〉GDB〉QLQ,各土壤上依次为F〉A〉E〉C〉D〉B．各品种第一茬平均株高依次为T308〉QLB〉GDB〉QLQ;第二茬依次为T308〉GDB〉QLB〉QLQ．各土壤第一茬平均株高依次为D〉A〉E〉B〉C〉F,第二茬依次为A〉B〉C〉E〉D〉F．各品种平均生物量依次为GDB〉T308〉QLB〉QLQ．各土壤上平均生物量依次为A〉C〉E〉B〉D〉F．结果表明蕹菜Cd积累典型品种的发芽和生长在不同土壤上呈现一定的稳定性,相关分析表明其生长特性与土壤EC、速效P、有效Pb含量等土壤因子相关．  相似文献   

15.
从水稻叶片中分离出两种天然脲类化合物:4-（邻硝基苯基）-3-硫代脲酸乙酯和4-（邻硝基苯基）-3-脲酸乙酯。两者的波谱分析数据已测得。它们具有特殊的生物活性。  相似文献   

16.
综述了当前作物转基因技术的三大主流方法农杆菌介导法、基因枪法、花粉管通道法等在农作物遗传改良中的研究进展,并阐述了这些转基因技术在水稻、小麦、棉花、玉米、大豆、苜蓿等主要农作物遗传转化现状.着重论述了作物转基因技术在抗病虫、抗逆、品质改良、雄性不育等方面对作物进行遗传改良的最新研究进展.  相似文献   

17.
INTRODUCTION Aluminum (Al) toxicity is one of the mostimportant yield-limiting factors for crop grown onacid upland and lowland acid sulphate soils (IRRI,1978). Al toxicity results in a reduced and damagedroot system, which in turn causes the affectedplants to be susceptible to drought stress and min-eral nutrient deficiencies (Foy, 1988). The physio-logical and biochemical mechanisms of the toxiceffect of Al on root elongation had been extensivelyinvestigated (Matsumoto, 2000). T…  相似文献   

18.
This study was designed to deepen insights on whether word-problem (WP) solving is a form of text comprehension (TC) and on the role of language in WPs. A sample of 325 second graders, representing high, average, and low reading and math performance, was assessed on (a) start-of-year TC, WP skill, language, nonlinguistic reasoning, working memory, and foundational skill (word identification, arithmetic) and (b) year-end WP solving, WP-language processing (understanding WP statements, without calculation demands), and calculations. Multivariate, multilevel path analysis, accounting for classroom and school effects, indicated that TC was a significant and comparably strong predictor of all outcomes. Start-of-year language was a significantly stronger predictor of both year-end WP outcomes than of calculations, whereas start-of-year arithmetic was a significantly stronger predictor of calculations than of either WP measure. Implications are discussed in terms of WP solving as a form of TC and a theoretically coordinated approach, focused on language, for addressing TC and WP-solving instruction.  相似文献   

19.
Aluminum (Al) toxicity is the major factor limiting crop productivity in acid soils. In this study, a recombinant inbreed line (RIL) population derived from a cross between an A1 sensitive lowland indica rice variety IR1552 and an Al tolerant upland japonica rice variety Azucena, was used for mapping quantitative trait loci (QTLs) for A1 tolerance. Three QTLs for relative root length (RRL) were detected on chromosome 1, 9, 12, respectively, and I QTL for root length under Al stress is identical on chromosome I after one week and two weeks stress. Comparison of QTLs on chromosome 1 from different studies indicated an identical interval between C86 and RZ801 with gene(s) for Al tolerance. This interval provides an important start point for isolating genes responsible for A1 tolerance and understanding the genetic nature of Al tolerance in rice. Four Al induced ESTs located in this interval were screened by reverse Northern analysis and confirmed by Northern analysis. They would be candidate genes for the QTL.  相似文献   

20.
粮食种植结构和布局的变化是粮食生产及农业生产发展状况的重要反映。清末,东北地区粮食种植结构的状况是高粱、大豆、谷子、小麦四大作物并举,并形成"南豆北麦"的商品粮基本格局。民国时期,东北粮食种植结构进一步变化,由于大豆生产商品化的发展,东北的粮食种植结构呈现出以大豆为主体的、单一化的形态。同时,随着农业商品经济的发展与繁荣,粮食生产布局发生变化,商品粮产地逐渐北移,东北地区的粮食生产走向专业化和区域化。  相似文献   

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