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Control Effects of Combination of Plant Induced Resistant Agents against Tobacco Mosaic Virus (TMV)
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作者 徐兴阳 董家红 +2 位作者 端永明 张廷金 杨龙祥 《Plant Diseases and Pests》 CAS 2011年第4期60-64,共5页
[ Objective] The paper was explore the control effects of combination of plant induced resistant agents against tobacco mosaic vires (TMV). [ Method ] The control effects of 6 different combinations of plant induced... [ Objective] The paper was explore the control effects of combination of plant induced resistant agents against tobacco mosaic vires (TMV). [ Method ] The control effects of 6 different combinations of plant induced resistant agents against TMV of flue-cured tobacco cultivar HangDa were studied under the environ- ment of simulated disease nursery. [ Result] The combination of 2 induced agents polypeptide-agent and 3-acetonyl-3-hydroxyoxindole (AHO) had good control effect against TMV, which could obviously delay the incidence time of TMV in infected tobacco plants. With water and Duxiao as control, their average control effects against TMV of tobacco plants during field period reached 69.64% and 43.25% after transplanting for 70 d. They also showed significant superiority accord- ing to Duncan's test (p = 0.05 ) in the aspects of plant height and leaf number, and the growth and development condition of leaves was good. Tobacco seedlings carrying TMV virus had no direct correlation with whether the symptoms performed, the seedlings carrying virus would perform symptom only when the incidence condition was suitable. The peak period for the incidence of TMV in seedlings carrying virus was during 19 d after transplanting. Spraying effective agents during nursery stage and field period, as well as promoting quick growth at the initial stage of tobacco seedlings after transplanting were the key measures to control its inci- dence. [ Conclusion] The study provided theoretical basis for preparing the control measures against TMV. 展开更多
关键词 tobacco mosaic virns(TMV) Induced disease-resistance Polypeptide-agent 3-acetonyl-3-hydroxyoxindole (AHO) Prevention and control China
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Effects of Early Infection of Tobacco Mosaic Virus on Photosynthetic Proteins and Its Control
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作者 Xiaojing XU Kunfeng SONG +3 位作者 Fengsheng HAO Jiajia ZHAO Hongxiang GUO Weiqun LIU 《Agricultural Biotechnology》 CAS 2019年第2期5-9,共5页
[Objectives] This study was conducted to explore the optimal period of TMV control and the physiological sites that interfere with TMV infection. [Methods] Proteome analysis was performed on the host tissues(tobacco p... [Objectives] This study was conducted to explore the optimal period of TMV control and the physiological sites that interfere with TMV infection. [Methods] Proteome analysis was performed on the host tissues(tobacco plants) at different time periods of viral infection, to verify the changes in the expression of differential protein genes and N and PR1-a in the photosynthetic pathway and porphyrin metabolism and chlorophyll metabolism pathways in proteome; and the tobacco plants were treated with different preparations. [Results] The expression levels of N and PR1-a in the tobacco leaves treated with preparation B reached the highest level, and the effects on the expression levels of the differential protein genes were also the most significant. The control effects of the preparations were tested by the half-leaf method, and the results showed that preparation B had a significant control effect against the early infection of the virus.[Conclusions] This study lays a foundation for the prevention and control of tobacco mosaic virus on crops. 展开更多
关键词 tobacco mosaic virus PROTEOME PHOTOSYNTHETIC system control effect
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Occurrence Regularity and Control of Tobacco Mosaic Virus (TMV) in Wuxi Tobacco Area of China in 2011
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作者 Li Zheng Xie Changsheng +6 位作者 Xiang Yongguang Cao Anquan Zhang Dengrong Chen Mingfu Shuai Hong Zhu Lingyan Jing Haixia 《Plant Diseases and Pests》 CAS 2013年第1期23-27,共5页
On the basis of general situation and new characteristics of tobacco mosaic virus (TMV) in Wuxi tobacco area in 2011, the paper expounded the objec-tive reasons of TMV via systemic investigation, field experiment an... On the basis of general situation and new characteristics of tobacco mosaic virus (TMV) in Wuxi tobacco area in 2011, the paper expounded the objec-tive reasons of TMV via systemic investigation, field experiment and date sorting. Meanwhile, combined with mcteorological conditions and results of systemic inves-tigation, the study especially analyzed meteorological conditions, outbreak and prevalence regularity of TMV and control efficacy of chemical reagents against TMV. The results showed that climatic conditions were the main conditions affecting TMV. There were three occurrence peaks of TMV in 2011, as a result of meteorologi-cal conditions of the months from April to June. The peaks were concerned with a wide range of rainfall about half a month before, low temperature, high humidity and scant sunshine and temperature jump after rain. The results of control effects showed that the chemical reagents could obviously prevent TMV, but once tobacco plants were infected, spraying chemical reagents would not have effective control effect against TMV. 展开更多
关键词 tobacco mosaic virus (TMV) Hue-cured tobacco Occurrence regularity -chemical control
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Control Effects of Different Agents on Tobacco Mosaic Virus Disease
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作者 Weiwei OUYANG Zhengyang ZHANG +9 位作者 Qiuzan ZHONG Changyou SHEN Runsheng LIU Xianyi XIAO Qinggen YANG Wenping RAO Yi LIU Chenggen FAN Hai LIAN Lifang XIE 《Agricultural Biotechnology》 CAS 2019年第6期27-29,63,共4页
[Objectives] This study was conducted to screen out suitable agents for controlling tobacco mosaic virus disease and the best control period in Zhangzhou tobacco area, providing a theoretical basis for the control of ... [Objectives] This study was conducted to screen out suitable agents for controlling tobacco mosaic virus disease and the best control period in Zhangzhou tobacco area, providing a theoretical basis for the control of virus diseases, thereby improving the quality of flue-cured tobacco and the income of tobacco farmers. [Methods] The effects on tobacco mosaic virus disease under the interaction between different agents and different application periods were investigated. The incidence of tobacco mosaic virus disease was investigated, and its control effect was analyzed. [Results] Different agents and different application periods had different control effects on tobacco mosaic virus disease. The incidence of tobacco mosaic virus disease: At 30 and 45 d after transplanting, the incidences of A2B1 treatment were the lowest, at 0.85%, 1.71%, respectively;and at 60 d after transplanting, the incidence of A3B1 treatment was the lowest, only 10.68%. The control effect: At 30 and 45 d after transplanting, A2B1 treatment had better control effects, reaching 79.39% and 73.06%, respectively. [Conclusions] 3% hypersensitive protein sprayed at 1 d before transplanting and 7 and 15 d after transplanting achieved the best effect, followed by 10% ningnanmycin sprayed at 1 d before transplanting and 7 and 15 d after transplanting. In tobacco production, it is recommended to apply 1 000 times dilution of 3% supersensitive protein microgranules for three times(at 1 d before transplanting and 7 and 15 d after transplanting), which can effectively prevent tobacco mosaic virus disease. 展开更多
关键词 tobacco mosaic virus disease control effect Hypersensitive protein Oligosaccharins-plant activation protein
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Distributed model predictive control based on adaptive sampling mechanism
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作者 Zhen Wang Aimin An Qianrong Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第11期193-204,共12页
In this work,an adaptive sampling control strategy for distributed predictive control is proposed.According to the proposed method,the sampling rate of each subsystem of the accused object is determined based on the p... In this work,an adaptive sampling control strategy for distributed predictive control is proposed.According to the proposed method,the sampling rate of each subsystem of the accused object is determined based on the periodic detection of its dynamic behavior and calculations made using a correlation function.Then,the optimal sampling interval within the period is obtained and sent to the corresponding sub-prediction controller,and the sampling interval of the controller is changed accordingly before the next sampling period begins.In the next control period,the adaptive sampling mechanism recalculates the sampling rate of each subsystem’s measurable output variable according to both the abovementioned method and the change in the dynamic behavior of the entire system,and this process is repeated.Such an adaptive sampling interval selection based on an autocorrelation function that measures dynamic behavior can dynamically optimize the selection of sampling rate according to the real-time change in the dynamic behavior of the controlled object.It can also accurately capture dynamic changes,meaning that each sub-prediction controller can more accurately calculate the optimal control quantity at the next moment,significantly improving the performance of distributed model predictive control(DMPC).A comparison demonstrates that the proposed adaptive sampling DMPC algorithm has better tracking performance than the traditional DMPC algorithm. 展开更多
关键词 chemical process Distributed model predictive control Adaptive sampling mechanism Optimal sampling interval System dynamic behavior
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Effect of Controlled Atmosphere Storage(CAS)Technology of Flue-cured Tobacco Laminas on the Alcoholization Quality of Tobacco
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作者 杨欣玲 《Agricultural Science & Technology》 CAS 2017年第12期2547-2553,共7页
To achieve the continuous maintainence of optimum quality state of flue- cured tobacco laminas and the effective regulation and control on alcoholization time for controlled atmosphere storage (CAS) method in the pr... To achieve the continuous maintainence of optimum quality state of flue- cured tobacco laminas and the effective regulation and control on alcoholization time for controlled atmosphere storage (CAS) method in the process of storage, the lam- ina samples of natural alcoholization for 1 year were selected. Comparable analysis on the appearance quality, chemical components and sensory quality of flue-cured tobacco laminas in the process of alcoholization was carried out by using the meth- ods of CAS and natural alcoholization. The results showed that appearance and color through the treatment of natural alcoholization were deep, browning and ac- companied by the phenomenon of oil, while color scale of flue-cured tobacco lami- nas through the treatment of CAS was uniform, fullness was better, and these two methods were close or identical after opening for 3 months. The contents of total sugar and reducing sugar during the process of alcoholization were also gradually decreased, but the ratio of reducing sugar to total sugar of laminas via CAS was higher than that of the natural alcoholization treatment. Compared with the natural alcoholization,the descending trends of total nitrogen and nicotine contents during CAS were gentler, the ratio via CAS was closer to 1, and the coordination of chemical components was more superior. During the period of alcoholization for 6 to 12 months, sensory quality of laminas via the natural alcoholization treatment was more superior than that of CAS treatment. However, after 18 months of alcoholiza- tion, sensory quality of laminas via the CAS treatment was more superior than that of the natural alcoholization treatment, and the CAS treatment could improve opti- mum sensory quality by 0.5 to 1.5 scores. Additionally, the CAS treatment could prolong the time of optimum alcoholization quality for 6 months, compared with the treatment of natural alcoholization. The CAS method could influence the alcohoJiza- tion quality of flue-cured tobacco laminas and prolong the retention period of opti- mum quality status for flue-cured tobacco laminas by regulating the environmental aas composition, thereby realizin.q quality control of flue-cured tobacco laminas. 展开更多
关键词 Flue-cured tobacco laminas controlled atmosphere storage (CAS) To-bacco alcoholization chemical components Sensory quality Alcoholization peak
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Test Bench for the Mechanical Distribution of Predators to Control Insect Pests 被引量:4
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作者 M. Khelifi F. Pare M. Aider 《Journal of Environmental Science and Engineering》 2011年第11期1445-1453,共9页
In agriculture, chemical insecticides are widely used to protect crops from insect pests. Over a period of years, some insects such as Colorado potato beetle (CPB) succeed in developing resistance to most of the reg... In agriculture, chemical insecticides are widely used to protect crops from insect pests. Over a period of years, some insects such as Colorado potato beetle (CPB) succeed in developing resistance to most of the registered chemical insecticides. Consequently, heavy applications of chemical insecticides to control this pest become ineffective on a long-term basis and can lead to serious health and environmental problems. The use of natural enemies to control CPB is an interesting alternative to chemical means However, hand release of predators is not feasible on a large scale in the field. The main objective of this research study was to design and build a test bench to investigate the technical feasibility of mechanically releasing predators. The test bench consisted of a vertical chain conveyor mounted on two vertical shafts driven by an electric motor. Since the predators are small and fragile, they were placed in a specially designed container to preserve their physical integrity. Trials using this test bench showed that a carrier material was required, because most of the predators remained inside the container. The success of this mass predator release system will be highly valuable for the biological control of insect pests in many crops. 展开更多
关键词 Insect pests chemical insecticides biological control natural enemies mass release mechanical distributor
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Design of a Mechanical Release System of Predator Insects to Control the Colorado Potato Beetle, Leptinotarsa Decemlineata (Say) 被引量:1
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作者 Sylvain de Ladurantaye Mohamed Khelifi 《Journal of Environmental Science and Engineering(B)》 2012年第6期756-762,共7页
The CPB (Colorado potato beetle), Leptinotarsa decemlineata (Say), is the major insect pest of potato crops in North America, Europe and Asia. Large amounts of chemical insecticides are used to control this insect... The CPB (Colorado potato beetle), Leptinotarsa decemlineata (Say), is the major insect pest of potato crops in North America, Europe and Asia. Large amounts of chemical insecticides are used to control this insect pest. Also, the CPB has developed over the years a resistance to most of the registered chemical insecticides, including those that were effective at one time. One of the most promising alternatives to chemical insecticides consists of taking advantage of natural enemies. The use of the stinkbug predator Perillus bioculatus to control the CPB has been successful at small scale. However, this natural enemy is not abundant in the nature and its hand release at large scale is not realistic. To remedy to this problem, predators must be massively released in potato fields using a mechanical distributor. Such a machine has been successfully designed and built at the Department of Soils and Agri-Food Engineering of University Lavak In this distributor, masses of predators are placed in small containers and mixed with a carrier material. In the field, the containers are mechanically opened at different locations, based on a source-point mass release option. These locations are determined in advance following a field monitoring of the populations of CPBs. Field trials proved that the mechanical distributor is reliable and ease of use. Its efficiency in releasing insect predators is high and comparable to that obtained in previous laboratory tests. 展开更多
关键词 POTATO Colorado potato beetle chemical insecticides biological control natural enemies source-point mass release mechanical distributor.
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Control of the Colorado Potato Beetle, Leptinotarsa decemlineata (Say), Using Predator Insects Released by a Mechanical Prototype
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作者 Saad Almady Mohamed Khelifi Marie-Pascale Beaudoin 《Journal of Environmental Science and Engineering(A)》 2012年第11期1279-1287,共9页
The CPB (Colorado potato beetle) is unquestionably the major insect pest of potato crops in North America, Europe, and Asia. The use of chemical insecticides to control this insect pest started in the 1860s. To date... The CPB (Colorado potato beetle) is unquestionably the major insect pest of potato crops in North America, Europe, and Asia. The use of chemical insecticides to control this insect pest started in the 1860s. To date, no registered chemical has been capable of effectively managing this agricultural pest. Moreover, the CPB has developed over the years a resistance to most of the registered chemical insecticides. The biological control through manual release of natural enemies of the CPB has been successful at small scale. However, hand release of these predators at large scale is not realistic. The objective of this study was to investigate the effectiveness of controlling the CPB through mechanical release of predator insects under real conditions in a potato field. Obtained results indicate that the mechanical release of predator insects resulted in a better control of the CPB populations and egg masses than the manual release. The success of this mechanical release of predator insects in potato fields will be highly valuable for the biological control of insect pests in many other row crops such as strawberry, lettuce, etc.. 展开更多
关键词 Colorado potato beetle chemical insecticides biological control mechanical release natural enemies Perillusbioculatus Podisus maculiventris.
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The chemical composition, quality control and pharmacological effects of Gualou-Xiebai-Banxia Decoction: a review
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作者 Yan-Tao Wang Yin-Yan Lai +4 位作者 Li Wang Xiao-Li Zheng Hong-Ju Li Su-Hong Chen Zheng Xiang 《Traditional Medicine Research》 2025年第4期72-82,共11页
Gualou-Xiebai-Banxia Decoction(GXBD)is a traditional Chinese herbal formula including four traditional Chinese medicines:Gualou(Trichosanthis Fructus,TF),Xiebai(Allii Macrostemonis Bulbus,AMB),Banxia(Pinelliae Rhizoma... Gualou-Xiebai-Banxia Decoction(GXBD)is a traditional Chinese herbal formula including four traditional Chinese medicines:Gualou(Trichosanthis Fructus,TF),Xiebai(Allii Macrostemonis Bulbus,AMB),Banxia(Pinelliae Rhizoma,PR)and yellow wine.It is a classical therapy for chest stuffiness and pain syndrome and is widely used in the clinical treatment of coronary heart disease.It also shows significant therapeutic effects on pulmonary heart disease,hyperlipidemia,and arrhythmia.This study conducted a literature review and collected information on GXBD from databases such as PubMed,Web of Science,China National Knowledge Infrastructure,and ScienceDirect.The result indicated that the main active ingredients of GXBD are steroids,flavonoids,terpenoids,alkaloids,amino acids,and organic acids.Trigonelline,macrostemonoside and cucurbitacin B can provide reference for its quality control.GXBD may exert therapeutic effects on coronary heart disease through AMPK,PI3K-AKT,oxLDL,VEGF,and NF-κB signal pathways.This review provides a comprehensive analysis and summary of the chemical composition and in vivo metabolism of three traditional Chinese medicines(TF,AMB,and PR),along with an evaluation of the chemical composition,quality control,pharmacological effects,and clinical application of GXBD.Based on these,areas requiring further research on GXBD have been proposed to provide a reference for its further development and new drug research. 展开更多
关键词 Gualou-Xiebai-Banxia Decoction chemical composition chest stuffiness quality control pharmacological mechanism
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化工机械设备与电气自动化控制的有机融合探讨
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作者 邓金艳 《模具制造》 2024年第8期168-170,共3页
现阶段,化工企业内的机械设备不断增多,这些导致机械设备的自动化控制难度更大,将化工机械设备和电气自动化控制有机融合,能够建立一个庞大有序的自动化控制体系,将全部的化工机械设备涵盖在内,为机械设备的自动化监管和控制提供有效的... 现阶段,化工企业内的机械设备不断增多,这些导致机械设备的自动化控制难度更大,将化工机械设备和电气自动化控制有机融合,能够建立一个庞大有序的自动化控制体系,将全部的化工机械设备涵盖在内,为机械设备的自动化监管和控制提供有效的技术支持。对此,就化工机械设备和电气自动化控制有机融合的意义、目标以及特点进行了分析,说明了化工机械设备和电气自动化控制融合的关键技术,并探究了具体的融合的应用。 展开更多
关键词 化工 机械设备 电气自动化及控制 融合
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烟草赤星病拮抗菌的筛选及其生防机理初探
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作者 孙伟霖 颜霞 +5 位作者 高剑欣 崔传斌 王平平 王娜娜 杨明明 黄丽丽 《山西农业大学学报(自然科学版)》 CAS 北大核心 2024年第5期58-67,共10页
[目的]本研究以烟草赤星病菌为靶标菌,筛选对其拮抗效果较好的生防菌,并对其进行后续的鉴定,同时初步设计试验验证生防机理,为烟草赤星病的拮抗生防菌资源、拮抗菌剂的制备等提供新的参考。[方法]采用初筛复筛获得生防菌后;绘制系统发... [目的]本研究以烟草赤星病菌为靶标菌,筛选对其拮抗效果较好的生防菌,并对其进行后续的鉴定,同时初步设计试验验证生防机理,为烟草赤星病的拮抗生防菌资源、拮抗菌剂的制备等提供新的参考。[方法]采用初筛复筛获得生防菌后;绘制系统发育树鉴定、抑菌谱系测定、菌株产酶活性测定、对赤星病病菌菌丝生长和孢子萌发的影响、诱抗定量检测、离体叶片防效等方法验证生防机理。[结果](1)筛得2株对于赤星病菌拮抗效果较好的生防菌,经由16S rDNA鉴定发现其分别是枯草芽孢杆菌(Bacillus subtilis)X768与贝莱斯芽孢杆菌(Bacillus velezensis)703;并完成了2株生防芽孢杆菌的抑菌谱系测定,证明其均具有抑菌广谱性;(2)对其生防机理探究过程中,菌株703具备产生纤维素酶、蛋白酶和淀粉酶的能力,菌株X768具备产生纤维素酶、蛋白酶、淀粉酶和脂肪酶的能力;2株生防芽孢杆菌均可抑制赤星病孢子的萌发和影响菌丝正常生长的形态,对于病原菌具有较强的抑制作用;(3)使用qRT-PCR法验证了生防菌对烟草防御基因通路(SA、JA、ET等通路)的影响,其中应用菌株703处理后烟草应用防御通路可能与SA通路、JA通路和泛素连接酶通路相关;而使用菌株X768处理后烟草应用防御通路可能与SA通路和泛素连接酶通路相关。[结论]筛得的具有抑制烟草赤星病作用的生防菌株B.subtilis X768与B.velezensis 703,抑菌谱较广,均可较强效果地抑制赤星病孢子的萌发和菌丝生长,并且2株生防菌均可引起烟草防御基因通路的上调,离体叶片防效效果较好。 展开更多
关键词 烟草赤星病 拮抗菌 生物防治 生防机理
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药剂对根结线虫病防效及烤烟产质量的影响
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作者 洪发彩 邹倩梅 +12 位作者 张敏 陈江政 徐俊 李晗梅 王戈 王娜 白羽祥 周鹏 杜宇 郑绍庚 曾皓 康铮 李杰 《中国农学通报》 2024年第22期131-136,共6页
对比化学药剂和微生物菌剂对烤烟根结线虫病防治的作用效果,为有效降低烤烟根结线虫病发生情况提供理论依据。设置对照喷施清水(Y_(0))、阿维菌素(Y_(1))、寡糖·噻唑膦(Y_(2))、杀线虫芽孢杆菌(Y_(3))、短短芽孢杆菌(Y_(4))等不同... 对比化学药剂和微生物菌剂对烤烟根结线虫病防治的作用效果,为有效降低烤烟根结线虫病发生情况提供理论依据。设置对照喷施清水(Y_(0))、阿维菌素(Y_(1))、寡糖·噻唑膦(Y_(2))、杀线虫芽孢杆菌(Y_(3))、短短芽孢杆菌(Y_(4))等不同处理,对比分析不同处理土壤理化性质和烤烟农艺性状、根结线虫病防治效果、光合特性、原烟外观质量、经济性状及烤后化学成分。结果表明,相较对照,Y_(4)处理显著提高了土壤速效养分及有机质含量,且显著促进了烟株生长,增强了烤烟对烟草根结线虫病的抗病性,发病率和病情指数分别较Y_(0)处理降低23.59个百分点、11.03;Y_(4)处理显著提高了烤烟的净光合速率、气孔导度、胞间CO_(2)浓度及SPAD值。烤烟的产量、均价、产值和中上等烟比例均以Y_(4)处理最高,分别比对照提高1.1、5.2、6.4、3.4个百分点;在烤后烟叶化学成分方面,Y_(2)处理总体更好。综上所述,短短芽孢杆菌对烟草根结线虫具有较好的防效,对改善土壤理化性质、促进烤烟生长发育提高产质量有较好效果。 展开更多
关键词 根结线虫病 烤烟 化学药剂 微生物菌剂 产质量 防治效果 土壤理化性质
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2018-2022年枣庄市小麦黄花叶病发生规律及春季药剂防治技术研究
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作者 种冬冬 杨宁 +4 位作者 赵士花 刘树艳 董艳 李瑞 王保刚 《农学学报》 2024年第9期6-11,共6页
本研究旨在探究小麦苗期黄花叶病的发生规律,并评估春季药剂防治的效果。从2018年起,在枣庄市进行了田间调查,以系统分析小麦黄花叶病发生情况。2022-2023年,选取3个地块开展苗期药剂防治试验。防治措施包括在小麦起身期每公顷喷施2次20... 本研究旨在探究小麦苗期黄花叶病的发生规律,并评估春季药剂防治的效果。从2018年起,在枣庄市进行了田间调查,以系统分析小麦黄花叶病发生情况。2022-2023年,选取3个地块开展苗期药剂防治试验。防治措施包括在小麦起身期每公顷喷施2次20%盐酸吗啉胍可湿性粉剂2250 g+30%毒氟磷可湿性粉剂750 g+0.01%芸苔素内酯可溶液剂225 mL+6%寡糖·链蛋白可湿性粉剂1200 g+98%磷酸二氢钾2250 g+含氨基酸水溶肥料750 g,面积分别为1333.4、666.7、666.7 m^(2),对照均喷施清水,面积分别为1333.4、666.7、666.7 m^(2)。研究结果表明,喷施上述药剂可以减轻小麦黄花叶病病情严重度,2次喷药后平均防效分别为29.6%、42.46%。与对照相比,喷药处理的小麦株高平均增加5.27 cm,单株鲜重平均增加0.44 g,单株次生根条数平均增加3.17条。3个试验地块的产量分别达到了5657.85、6777.12、7868.37 kg/hm2,而对照地块的产量分别为4776.52、5435.58、7223.63 kg/hm^(2)。因此,喷药处理的产量较对照分别提高了881.32、1341.54、644.75 kg/hm^(2),平均增产955.87 kg,平均增产幅度为17.35%。综上所述,小麦苗期通过喷施特定混合药剂,可以有效减低黄花叶病的危害,实现减损和增产的目的。本研究结果为小麦黄花叶病的防治提供了重要的理论依据和技术支持。 展开更多
关键词 枣庄 小麦黄花叶病 发生规律 调查 春季 药剂防治 研究
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烟叶远程可视化调控烘烤适用性研究 被引量:1
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作者 杨学书 和强 +3 位作者 夏开逵 李彦霖 木潆 马文广 《安徽农业科学》 CAS 2024年第10期175-177,189,共4页
为探索远程可视化调控烘烤的实际应用价值,选用云烟99烤烟品种的中部叶(11~13叶位)为试验材料,采用远程调控烘烤与现场烘烤开展对比试验。结果表明:在经济效益、化学成分和感官评吸质量上,与现场烘烤比较,采用远程调控烘烤的烤后烟叶,... 为探索远程可视化调控烘烤的实际应用价值,选用云烟99烤烟品种的中部叶(11~13叶位)为试验材料,采用远程调控烘烤与现场烘烤开展对比试验。结果表明:在经济效益、化学成分和感官评吸质量上,与现场烘烤比较,采用远程调控烘烤的烤后烟叶,无明显差异,均可达到优质烟叶水平。通过远程可视化调控烘烤技术,其质量效果可以达到现场烘烤的水平。未来需要持续升级和改进远程可视化调控烘烤技术,以实现对烟叶烘烤过程的即时监管和有效数据收集。这将从根本上提高烟叶烘烤的效率,实现烟叶烘烤质量的提升。 展开更多
关键词 烟叶 远程调控烘烤 经济效益 化学成分 感官评吸
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昆虫对杀虫剂和转Bt基因植物的抗性进化机制研究进展
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作者 彭羽佳 李文萃 刘勇波 《生物技术通报》 CAS CSCD 北大核心 2024年第4期40-51,共12页
为防治昆虫对农作物的危害,采取了喷施杀虫剂和种植转Bt基因抗虫植物等措施。然而,杀虫剂的大规模使用和转Bt基因抗虫植物的大面积连续种植使得一些靶标昆虫产生了抗性进化,这不仅影响防治效果,而且还影响整个农业生态系统服务功能。本... 为防治昆虫对农作物的危害,采取了喷施杀虫剂和种植转Bt基因抗虫植物等措施。然而,杀虫剂的大规模使用和转Bt基因抗虫植物的大面积连续种植使得一些靶标昆虫产生了抗性进化,这不仅影响防治效果,而且还影响整个农业生态系统服务功能。本文综述了昆虫对化学杀虫剂、微生物杀虫剂和转Bt基因植物产生抗性的分子机制。昆虫对化学杀虫剂的抗性进化机制主要是靶标位点敏感性下降和解毒酶系活性增强;对微生物杀虫剂的抗性进化机制主要是免疫系统激活和共生菌群变化;对转Bt基因植物的抗性进化机制主要是昆虫中肠结合受体基因突变或表达下调和中肠蛋白酶活性降低。为了减缓昆虫抗性进化和提高杀虫剂效率,未来建议减少使用化学杀虫剂,合理利用杀虫谱广和活性高的微生物杀虫剂以及抗虫植物等方法系统治理农业害虫。 展开更多
关键词 昆虫防治 化学杀虫剂 微生物杀虫剂 转Bt基因植物 抗性机制
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New discrimination method for ablative control mechanism in solid-propellant rocket nozzle 被引量:3
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作者 ZHANG Bin, LIU Yu, WANG ChangHui & REN JunXue School of Astronautics, Beijing University of Aeronautics and Astronautics, Beijing 100083, China 《Science China(Technological Sciences)》 SCIE EI CAS 2010年第10期2718-2724,共7页
A reasonable discrimination method for ablative control mechanism in solid-propellant rocket nozzle can improve the calculation accuracy of ablation rate. Based on the different rate constants for reactions of C with ... A reasonable discrimination method for ablative control mechanism in solid-propellant rocket nozzle can improve the calculation accuracy of ablation rate. Based on the different rate constants for reactions of C with H2O and CO2,a new discrimination method for ablative control mechanism,which comprehensively considers the influence of nozzle surface temperature and gas component concentration,is presented. Using this new discrimination method,calculations were performed to simulate the nozzle throat insert ablation. The numerical results showed that the calculated ablation rate,which was more close to the measured values,was less than the value calculated by diffusion control mechanisms or by double control mechanisms. And H2O was proved to be the most detrimental oxidizing species in nozzle ablation. 展开更多
关键词 nozzle Ablation diffusion control mechanism chemical kinetics control mechanism DISCRIMINATION METHOD
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深度调剖化学剂驱油机理及实验研究
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作者 闫海建 贾东林 +2 位作者 齐永宁 李焕 王少楠 《当代化工》 CAS 2024年第6期1287-1290,1299,共5页
基于分子设计及化学反应合成了化学驱油剂HPEN体系,分析了催化剂质量分数、反应温度、反应时间及投料比等因素对反应产率的敏感性。通过正交方案设计优选了HPEN的合成条件,岩心驱替实验评价了HPEN与磺酸盐复配体系的驱油特性,选取目标... 基于分子设计及化学反应合成了化学驱油剂HPEN体系,分析了催化剂质量分数、反应温度、反应时间及投料比等因素对反应产率的敏感性。通过正交方案设计优选了HPEN的合成条件,岩心驱替实验评价了HPEN与磺酸盐复配体系的驱油特性,选取目标区块进行了现场应用实验。结果表明:HPEN适宜的合成条件为催化剂质量分数5%、反应温度100℃、反应时间6 h、脂肪醇聚氧乙烯醚与磺酸盐投料比1∶1.5。无机盐离子的存在会不同程度影响HPEN溶液体系的界面张力。1.0%的HPEN与磺酸盐按质量比3∶1复配时效果最佳,此时体系抗温能力为130℃,高矿化度溶液体系其界面张力仍处于10-2 mN·m^(-1)数量级范围。复配体系可显著提高现场原油采收率,实现老井日均产油4 t、日均产液16 m^(3)的效果。 展开更多
关键词 深度调剖 化学剂 驱油机理 采收率
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植物根际促生菌在烟草根茎类病害防治中的应用研究进展
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作者 闵琪茹 甘勇 +3 位作者 陈寿明 杨章明 杨鹏 李斌 《现代农业科技》 2024年第11期108-112,116,共6页
烟草是重要的经济作物,经济价值高。烟草根茎类病害的发生导致一定的烟草损失。本文阐述了烟草根黑腐病、烟草黑胫病和烟草青枯病等烟草根茎类病害的发生和危害,分析了烟草根茎类病害的防治现状,包括农业防治、化学防治和生物防治等内容... 烟草是重要的经济作物,经济价值高。烟草根茎类病害的发生导致一定的烟草损失。本文阐述了烟草根黑腐病、烟草黑胫病和烟草青枯病等烟草根茎类病害的发生和危害,分析了烟草根茎类病害的防治现状,包括农业防治、化学防治和生物防治等内容,提出了植物根际促生菌的研究进展,探讨了其作用机制及在防治烟草病害中的应用前景,总结了用于防治烟草病害的植物根际促生菌主要种类,提出了相关展望,以期为有效防治烟草根茎类病害和推广应用植物根际促生菌提供参考。 展开更多
关键词 烟草根茎类病害 植物根际促生菌 作用机制 防治现状 展望
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水杨酸对烟草病毒病的防效与烟苗生理活性的影响
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作者 董瑜 谢晏芬 +7 位作者 赵宇婷 贾中清 王文波 李恺 张国洪 张艳艳 马力 彭瑞琦 《贵州农业科学》 CAS 2024年第6期61-67,共7页
【目的】探明喷施水杨酸对烤烟普通花叶病的防效与烟苗生理活性的影响,为水杨酸绿色防控烟草病毒病提供理论依据。【方法】采用漂浮育苗和盆栽试验方法研究喷施不同浓度[T_(1)(0.50 mmol/L)、T_(2)(0.75 mmol/L)和T_(3)(1.0 mmol/L)]水... 【目的】探明喷施水杨酸对烤烟普通花叶病的防效与烟苗生理活性的影响,为水杨酸绿色防控烟草病毒病提供理论依据。【方法】采用漂浮育苗和盆栽试验方法研究喷施不同浓度[T_(1)(0.50 mmol/L)、T_(2)(0.75 mmol/L)和T_(3)(1.0 mmol/L)]水杨酸对烟株病毒病的病情指数和叶片防御酶活性的影响。【结果】喷施不同浓度水杨酸,烟苗叶片的防御酶活性在处理3~6 d时达最高峰;T_(1)和T_(2)防御酶活性和脯氨酸含量较高。其中,POD活性,T_(1)~T_(3)在处理3~6d时较清水对照(CK)分别提高68.00%~74.36%、34.23%~44.22%和4.39%~21.81%。SOD活性,在处理3 d时达最高,较CK分别提高49.47%、65.71%和27.27%。几丁质酶活性,T_(2)在处理3 d时达最高,为925.55 U/g;T_(1)和T_(3)在处理6 d时达最高,分别为1231.75U/g和820.45 U/g,T_(1)较CK提高67.12%。β-1,3-葡聚糖酶活性,均在处理3 d时达最高,较CK分别提高97.12%、59.37%和58.23%。脯氨酸含量,均在处理6 d时达最高,较CK分别提高29.41%、27.71%和17.80%。0.75mmol/L水杨酸处理烟株病毒病的病情指数为26.22,远低于CK(64.80),防控效果达59.53%。【结论】水杨酸可诱导烟叶POD、SOD、几丁质酶、β-1,3-葡聚糖酶活性和脯氨酸含量增加,与烟苗对病毒病的抗性密切相关。 展开更多
关键词 烤烟 水杨酸 普通花叶病 防御酶活性 脯氨酸 绿色防控
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