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基于L(0,1)模态农田灌溉管道缺陷检测技术研究 预览
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作者 栗霞飞 刘飞 +2 位作者 赵满全 刘晓东 杜兰 《农机化研究》 北大核心 2020年第1期14-18,共5页
由于农田灌溉管道是裸露在空气中的,使得管道很容易受到环境的影响,如发生腐蚀、老化等现象,造成管道的泄漏及水资源的严重浪费。因此,对灌溉管道的缺陷检测具有重要的理论意义和实际价值。为此,利用超声导波检测技术对管道缺陷的定位... 由于农田灌溉管道是裸露在空气中的,使得管道很容易受到环境的影响,如发生腐蚀、老化等现象,造成管道的泄漏及水资源的严重浪费。因此,对灌溉管道的缺陷检测具有重要的理论意义和实际价值。为此,利用超声导波检测技术对管道缺陷的定位进行了研究,选用超声导波中的L(0,1)模态对管道的缺陷进行检测,观察L(0,1)模态在充液管与未充液管、完整管与缺陷管、直管与弯管中的传播特性,对比直管和弯管的传播特性,并分析缺陷对传播特性与能量分布情况的影响。研究发现:L(0,1)模态在液体中传播时,大部分能量会损耗在液体中,波在完整管中传播的速度大于缺陷管,在弯管中传播时损耗的能量普遍高于直管,根据这些特性就可以实时监测管道,防止管道因泄露造成资源浪费。 展开更多
关键词 灌溉管道 泄露 缺陷 L(0 1)模态
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Genetic Diversity of Clover by SRAP 预览
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作者 Runfang LI Hanfeng DING +2 位作者 Cune WANG Lingyun LU Xiaodong ZHANG 《农业生物技术:英文版》 CAS 2019年第5期6-8,共3页
In the present study,genetic diversity and genetic relationship of 11materials including red clover ( Trifolium pretense L.),white clover ( T.repen L.) and alsike clover ( T.hybridum L.) and leaf-type variants of whit... In the present study,genetic diversity and genetic relationship of 11materials including red clover ( Trifolium pretense L.),white clover ( T.repen L.) and alsike clover ( T.hybridum L.) and leaf-type variants of white clover were investigated by SRAP (sequence related amplified polymorphism).Forty SRAP primers were screened,and 792 reliable bands were amplified,among which 426 (53.8%) were polymorphic.The number of polymorphic bands per pair of primers ranged from 3 to 38 with an average of 10.6.SRAP cluster analysis showed that the similarity coefficients between white clover materials were from 0.465 to 0.997 with an average of 0.812,indicating that there was certain genetic diversity among white clover.Specific bands appeared in white clover variants,indicating that there were certain differences in DNA sequence between normal while clover plants and their leaf-type variants.The similarity coefficients between red clover materials were from 0.457 to 0.827 with an average of 0.597,indicating that the different red clover germplasms had genetic diversity at the DNA molecular level.The results also showed that the genetic relationship of the alsike clover with the red clover was closer than that with the white clover.This study shows that SRAP technique can be effectively used for the analysis on interspecific and intraspecific relationship,germplasm resource identification and genetic diversity of clover. 展开更多
关键词 WHITE CLOVER ( TRIFOLIUM repen L.) RED CLOVER ( TRIFOLIUM pratense L.) Alsike CLOVER ( TRIFOLIUM hybridum L.) SRAP
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In vivo antiplasmodial potential of three herbal methanolic extracts in mice infected with Plasmodium berghei NK65
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作者 Pachiyappan Rajiv Gandhi Chinnaperumal Kamaraj +1 位作者 Elangovan Vimalkumar Selvaraj Mohana Roopan 《中草药:英文版》 CAS 2019年第3期299-307,共9页
Objective: The present study deals with the investigation of antiplasmodial potential of leaf methanolic extract of Aegle marmelos, Aristolochia indica and Cassia auriculata against Plasmodium berghei(NK65)infected mi... Objective: The present study deals with the investigation of antiplasmodial potential of leaf methanolic extract of Aegle marmelos, Aristolochia indica and Cassia auriculata against Plasmodium berghei(NK65)infected mice.Methods: The chloroquine-sensitive parasites P. berghei(1 × 106) were inoculated into Swiss albino mice intraperitoneally. The methanol extracts of three herbal plants were orally administered in P. berghei infected mice which were further assessed using the four-day suppressive test at different doses of 150, 300 and 600 mg/kg per day. Chloroquine(CQ) was used as the standard drug with of 1.25, 2.5 and 5 mg/kg concentrations and was orally administered.Results: The leaves of A. marmelos, A. indica, and C. auriculata were found to suppress P. berghei parasitaemia in Swiss albino mice by(67.0 ± 4.02)%,(72.0 ± 8.44)% and(52.7 ± 2.06)% at 600 mg/kg/d with ED50 values of 284.73, 233.77 and 562.48 mg/kg, respectively. These herbal plants increased the mean survival time of infected mice and prevented body weight loss. GC-MS analysis revealed the presence of hentriacontan-16-one(C31 H62 O) in A. indica extract. The histopathology study showed non-toxic to kidney and liver at 600 mg/kg/body weight.Conclusions: Overall results revealed that herbal plants may be active in the development of novel and cheap antimalarial compounds. 展开更多
关键词 Aegle marmelos L. ARISTOLOCHIA indica L. Cassia auriculata L. GC-MS histopathology in vivo ANTIPLASMODIAL POTENTIAL Plasmodium berghei(NK65) Swiss ALBINO MICE
陆地棉亲本间遗传距离与杂种优势的相关性研究 预览
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作者 曲玉杰 孙君灵 +9 位作者 耿晓丽 王骁 Zareen Sarfraz 贾银华 潘兆娥 何守朴 龚文芳 王立如 庞保印 杜雄明 《中国农业科学》 CAS CSCD 北大核心 2019年第9期1488-1500,共13页
[目的]通过1500个陆地棉杂交组合分析杂种优势与其亲本间数量性状遗传距离的相关性,探讨能否利用大规模杂交组合亲本间遗传距离提高陆地棉杂种优势预测效果,以期为棉花杂交育种和杂种优势利用提供理论指导。[方法]选择来自15个国家和中... [目的]通过1500个陆地棉杂交组合分析杂种优势与其亲本间数量性状遗传距离的相关性,探讨能否利用大规模杂交组合亲本间遗传距离提高陆地棉杂种优势预测效果,以期为棉花杂交育种和杂种优势利用提供理论指导。[方法]选择来自15个国家和中国23个省(市)的305份陆地棉核心种质为亲本,采用L×T(Line×Tester)杂交设计配制1500个杂交组合。2012-2013年,在中国南北方13个生态环境下考察其株高、单铃重、衣分、纤维长度等10个产量和纤维品质相关性状,分析F1杂种优势、亲本间遗传距离和群体结构,并采用4种方式(Cor1-Cor4)计算遗传距离与杂种优势的相关性。[结果]10个性状中亲优势(MPH)均值的变幅为1.70%7.40%,平均为4.36%,按父本不同将F1分成5组(AE),其MPH均值A>E>B>C>D;超亲优势(HB)均值的变幅为-4.17%1.87%,平均为-0.17%,A、B和E组的HB均值皆为正。10个性状在5组中除D、E组的马克隆值之外,其他性状普遍具有明显的中亲优势,其中,单铃重和纤维长度的中亲优势在5组中均以正优势为主(达80%以上),最大值分别为34.01%和9.83%,对应的超亲优势分别为24.25%和5.80%。F1和亲本差异显著性分析表明单铃重、株高、纤维长度、伸长率和整齐度指数整体表现出一定的超亲优势。父本(测试种)与300个母本之间的遗传距离介于2.28061.430,平均为21.550,5个测试种与母本间的平均遗传距离D>C>E>A>B,其中,最近值为11.721,最远值为33.271。按最小方差聚类,将305个陆地棉亲本划分为2个主群,包括5个亚群。4种遗传距离与杂种优势的相关性分析结果显示,因样本量、遗传距离变幅和父本不同其结果有所差异,相关性随样本量的增大而有所增强。其中,Cor1是Cor2结果的整体体现;Cor3与Cor1和Cor2相比,部分性状的中亲优势与遗传距离的相关性有所不同;Cor4的相关性最弱。综合来看,遗传距离与衣分、断裂比强度、整齐度指数 展开更多
关键词 陆地棉 核心种质 数量性状 L×T 遗传距离 聚类分析 杂种优势预测
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检测胃黏膜上皮细胞微量元素、DNA、P53、Ki-67、C-erbB2、P21ras研究中医脾虚证和胃癌前病变的关系
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作者 孙传菊 尹光耀 +1 位作者 张武宁 陈一 《辽宁中医杂志》 CAS 2019年第2期238-240,445共4页
目的:探索中医脾虚证的病理生理学变化与胃黏膜癌前病变的关系。方法:对160例脾虚证胃黏膜均伴有肠上皮化生(intestinal metaplasia,IM)和/或低级别上皮内瘤变(low grade intraepithe1ial neoplasia,L-IN)患者,脾虚证分为脾气虚证(splee... 目的:探索中医脾虚证的病理生理学变化与胃黏膜癌前病变的关系。方法:对160例脾虚证胃黏膜均伴有肠上皮化生(intestinal metaplasia,IM)和/或低级别上皮内瘤变(low grade intraepithe1ial neoplasia,L-IN)患者,脾虚证分为脾气虚证(spleen Qi deficiency,SQD)、脾阴虚证(spleen Yin deficiency,SyinD)和脾虚气滞证(spleen deficiency with Qi stagnation,SDQS)三型和22例健康对照者为研究对象,采用现代科学仪器和技术检测胃黏膜上皮细胞核和线粒体的微量元素、DNA与胃黏膜P53,Ki-67,C-erbB2,P21ras。结果:SDQS组与L-IN间在分子生物学上也无显著性的差异。结论:要定期随访检测以上指标。有利于早期发现慢性胃炎的癌变。 展开更多
关键词 脾虚证 L-IN IMⅡ_b 胃黏膜上皮细胞核和线粒体 微量元素 胃黏膜P53 KI-67 C-ERBB2 P21RAS
Am原子及其离子Am^q+(q=1~6)的K,L,M-X射线跃迁能和跃迁几率的理论研究 被引量:1
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作者 N. J. Dalal 武中文 +2 位作者 丁晓彬 颉录有 董晨钟 《原子核物理评论》 CAS CSCD 北大核心 2019年第1期111-117,共7页
使用基于Dirac-Hartree-Fock方法的Grasp2K程序包,计算了Am原子及离子的K,L,M-X射线的跃迁能和跃迁速率。在计算中,包括了Breit相互作用、真空极化和自能等重要效应。目前研究结果与已有的其他实验和理论结果相对误差约为0.04%。此外,... 使用基于Dirac-Hartree-Fock方法的Grasp2K程序包,计算了Am原子及离子的K,L,M-X射线的跃迁能和跃迁速率。在计算中,包括了Breit相互作用、真空极化和自能等重要效应。目前研究结果与已有的其他实验和理论结果相对误差约为0.04%。此外,我们还首次计算了从Am^1+到Am^6+离子的K, L, M-X射线的跃迁能和跃迁速率。相对于中性原子,来自低离化态的跃迁能相对于中性的相应跃迁线的能量仅有轻微的偏移,这反映出外层电子几乎不影响内壳层的跃迁性质。 展开更多
关键词 K L M-X射线 跃迁能 跃迁速率
Effects of Different Herbicides on the Control of Malachium aquaticum L. and Poa annua L. 预览
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作者 Guiyuan MENG Yanyan CHEN +3 位作者 Ye JIN Jing ZHOU Sijia YU Maoyuan WANG 《亚洲农业研究:英文版》 2019年第5期79-82,96共5页
In this experiment,the effects of 13 kinds of herbicides( or mixtures) on the control of two kinds of weeds were studied by pot cultivation with the broadleaf weed Malachium aquaticum L. and Gramineae weed Poa annua L... In this experiment,the effects of 13 kinds of herbicides( or mixtures) on the control of two kinds of weeds were studied by pot cultivation with the broadleaf weed Malachium aquaticum L. and Gramineae weed Poa annua L. as the materials. The results showed that the herbicide MCPA-Na had the best and fastest control effect on M. aquaticum L.,and all the M. aquaticum L. died 7 d after treatment;it was followed by the other four herbicides including MCPA-Na + clethodim,MCPA-Na + quizalofop-p-ethyl,bentazon and nicosulfuron·atrazine,and all the M. aquaticum L. died 14 d after treatment. Atrazine was the best herbicide to control Gramineae weeds,followed by nicosulfuron·atrazine,and mesotrione·nicosulfuron·atrazine. The study on the application of field herbicide found that four herbicides including atrazine,mesotrione·nicosulfuron·atrazine,nicosulfuron·atrazine and bentazon had better control effect on weeds. The best herbicide for flax field was MCPA-Na + clethodim,followed by MCPA-Na and MCPA-Na + quizalofop-p-ethyl. The optimized herbicides and combinations had no harmful effects on the growth of corn and flax. 展开更多
关键词 HERBICIDES WEEDS Malachium aquaticum L. POA annua L. CONTROL effect
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Genome-wide identification and expression L^r analysis of DNA demethylase family in cotton 预览
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作者 YANG Xiaomin LU Xuke +8 位作者 CHEN Xiugui WANG Delong WANG Junjuan WANG Shuai GUO Lixue CHEN Chao WANG Xiaoge WANG Xinlei YE Wuwei 《棉花研究(英文)》 2019年第3期142-150,共9页
Background:DNA methylation is an important epigenetic factor that maintains and regulates gene expression.The mode and level of DNA methylation depend on the roles of DNA methyltransferase and demethylase,while DNA de... Background:DNA methylation is an important epigenetic factor that maintains and regulates gene expression.The mode and level of DNA methylation depend on the roles of DNA methyltransferase and demethylase,while DNA demethylase plays a key role in the process of DNA demethylation.The results showed that the plants DNA demethylase all contained conserved DNA glycosidase domain.This study identified the cotton DNA demethylase gene family and analyzed it using bioinformatics methods to lay the foundation for further study of cotton demethylase gene function.Results:This study used genomic information from diploid Gossypium raimondii JGI(D),Gossypium arboreum L.CRI(A),Gossypium hirsutum L.JGI(AD1)and Gossypium barbadebse L.NAU(AD2)to Arabidopsis thaliana.Using DNA demethylase genes sequence of Arabidopsis as reference,25 DNA demethylase genes were identified in cotton by BLAST analysis.There are 4 genes in the genome D,5 genes in the genome A,10 genes in the genome AD1,and 6 genes in the genome AD2.The gene structure and evoluti on were analyzed by bioinfo rm atics,and the expression patterns of DNA demethylase gene family in Gossypium hirsutum L.were analyzed.From the phylogenetic tree analysis,the DNA demethylase gene family of cotton can be divided into four subfamilies:REPRESSOR of SILENCING 1(R0S1),DEMETER(DME)Z DEMETER-LIKE 2(DML2),and DEMETER-LIKE3(DML3).The sequence similarity of DNA demethylase genes in the same species was higher,and the genetic relationship was also relatively close.Analysis of the gene structure revealed that the DNA demethylase gene family members of the four subfamilies varied greatly.Among them,the number of introns of R0S1 and DME subfamily was larger,and the gene structure was more complex.For the analysis of the conserved domain,it was known that the DNA demethylase family gene member has an endonuclease Ⅲ(ENDO3c)domain.Conclusion:The genes of the DNA demethylase family are distributed differently in different cotton species,and the gene structure is very different.High expression 展开更多
关键词 DNA demethylase Gossypium arboreum L. Gossypium barbadebse Lf Gossypium hirsutum L. Gossypiumraimondii
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Optimization on Ultrasonic Extraction Method of Total Flavonoids for Liriodendron chinense Sarg.× L. tulipifera L. by Response Surface Methodology (RSM) 预览
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作者 Yi JIANG Xuqin REN +2 位作者 Gang LI Guoqing PAN Run ZHUO 《农业生物技术:英文版》 CAS 2019年第5期132-135,共4页
With the leaves,bark and roots of Liriodendron chinense Sarg.× L.tulipifera L.as experiment materials,the ultrasonic-assisted extraction conditions of total flavonoids were optimized by response surface Box-Behnk... With the leaves,bark and roots of Liriodendron chinense Sarg.× L.tulipifera L.as experiment materials,the ultrasonic-assisted extraction conditions of total flavonoids were optimized by response surface Box-Behnken test design.Ultrasonic time and liquid-to-solid ratio had significant effects on the extraction amount of flavonoids from the leaves of L.chinense Sarg.× L.tulipifera L.;ultrasonic temperature and liquid-to-solid ratio had an interaction on the extraction amount of flavonoids;and the optimum ultrasonic time,temperature and liquid-to-solid ratio for the extraction of flavonoids from leaves of L.chinense Sarg.× L.tulipifera L.were 19.82 min,28.60 ℃ and 9.48 ml/g,respectively.Ultrasonic time,temperature and liquid-to-solid ratio had significant effects on the extraction amount of flavonoids from L.chinense Sarg.× L.tulipifera L.;there was a significant interaction between any two of the factors,which had a significant effect on the extraction of flavonoids;and the optimum extraction parameters for flavonoids in the bark were the ultrasonic time of 33.66 min,the ultrasonic temperature at 32.85 ℃ and the liquid-to-solid ratio of 11.39 ml/g.Ultrasonic time and liquid-to-solid ratio had significant effects on the extraction of flavonoids from roots;there was a significant interaction between ultrasonic time and liquid-to-solid ratio and between ultrasonic temperature and liquid-to-solid ratio;and the optimum extraction parameters for flavonoids from the roots of L.chinense Sarg.× L.tulipifera L.were the ultrasonic time of 32.38 min,the ultrasonic temperature at 25.0 ℃ and the liquid-to-solid ratio of 8.00 ml/g.The results of the three models were stable.The models are feasible and have good application value. 展开更多
关键词 Response surface METHODOLOGY LIRIODENDRON chinense Sarg.× L. tulipifera L. TOTAL FLAVONOIDS ULTRASONIC extraction
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Induced Mutation for Developing Mutant Rice Lines Tolerant to the Parasitic Weed Striga asiatica (L.) Kuntze 预览
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作者 Noronirina Victorine Rakotoarisoa Harimialimalala Jhonny Rabefiraisana +5 位作者 Lydia Razafinirina Berthe Rasoamampionona Xavier Roland Rakotonjanahary Abdelbagi Ali Ghanim Mukhtar Ljupcho Jankuloski Alice Andrianjaka 《环境科学与工程:A》 2019年第5期181-192,共12页
This work aims to screen mutant rice lines tolerant to Striga asiatica.Two rainfed sensitive rice varieties B22 and F154 were used.Plants survival rates of the two parents were significantly lower respectively(9.74a a... This work aims to screen mutant rice lines tolerant to Striga asiatica.Two rainfed sensitive rice varieties B22 and F154 were used.Plants survival rates of the two parents were significantly lower respectively(9.74a and 11.83a)than those of mutant lines(55.36c to 74.36b);Striga plants emergence/pot were significantly higher for the parents(13.96c and14.89c)compared to the mutants(0.12a to 1.5b);the infection rate of parents(7.37b;7.86b)was higher compared to the mutants(2.27a to 2.74a);fertility rate/plant of parents was lower(20.98%b;22.29%b)but much higher than mutants(72.19%b to 78.35%b);the average panicle number/plant of parents was significantly lower(0.5a;1a)than those of mutants(1.5b to 2.4bc)and the 100 g grain weight of parents are lower(2.35a;2.56a)than those of mutants(3.19b to 3.23b).The culture of those mutant lines may increase rice production and contribute to enhancing food security in Madagascar. 展开更多
关键词 Induced mutation mutant tolerant lines rice (Oryza sativa L.) parasitic weed Striga asiatica (L.) Kuntze.
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Arbuscular mycorrhizal fungi combined with exogenous calcium improves the growth of peanut(Arachis hypogaea L.)seedlings under continuous cropping 预览
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作者 CUI Li GUO Feng +6 位作者 ZHANG Jia-lei YANG Sha MENG Jing-jing GENG Yun WANG Quan LI Xin-guo WAN Shu-bo 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第2期407-416,共10页
The growth and yield of peanut are negatively affected by continuous cropping.Arbuscular mycorrhizal fungi(AMF)and calcium ions(Ca2+)have been used to improve stress resistance in other plants,but little is known abou... The growth and yield of peanut are negatively affected by continuous cropping.Arbuscular mycorrhizal fungi(AMF)and calcium ions(Ca2+)have been used to improve stress resistance in other plants,but little is known about their roles in peanut seedling growth under continuous cropping.This study investigated the possible roles of the AMF Glomus mosseae combined with exogenous Ca2+in improving the physiological responses of peanut seedlings under continuous cropping.G.mosseae combined with exogenous Ca2+can enhance plant biomass,Ca2+level,and total chlorophyll content.Under exogenous Ca2+application,the Fv/Fm in arbuscular mycorrhizal(AM)plant leaves was higher than that in the control plants when they were exposed to high irradiance levels.The peroxidase,superoxide dismutase,and catalase activities in AM plant leaves also reached their maximums,and accordingly,the malondialdehyde content was the lowest compared to other treatments.Additionally,root activity,and content of total phenolics and flavonoids were significantly increased in AM plant roots treated by Ca2+compared to either G.mosseae inoculation or Ca2+treatment alone.Transcription levels of AhCaM,AhCDPK,AhRAM1,and AhRAM2 were significantly improved in AM plant roots under exogenous Ca2+treatment.This implied that exogenous Ca2+might be involved in the regulation of G.mosseae colonization of peanut plants,and in turn,AM symbiosis might activate the Ca2+signal transduction pathway.The combination of AMF and Ca2+benefitted plant growth and development under continuous cropping,suggesting that it is a promising method to cope with the stress caused by continuous cropping. 展开更多
关键词 ARACHIS HYPOGAEA L. ARBUSCULAR MYCORRHIZAL fungi continuous CROPPING exogenous calcium
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黄金茶CsDAM2基因克隆及其功能分析
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作者 龚志华 丰金玉 +4 位作者 向奕 唐雨薇 秦昱 肖文军 刘硕谦 《分子植物育种》 CAS CSCD 北大核心 2019年第12期3887-3893,共7页
休眠是通过植物体内相应基因的表达调控机制,使植物芽停止生长,以适应外界低温、短日照等不良环境条件的结果。茶芽打破休眠的早晚,密切关系到茶树经济生产的效益。为进一步掌握茶树芽休眠与解除的分子机理>本研究克隆了可能与黄金... 休眠是通过植物体内相应基因的表达调控机制,使植物芽停止生长,以适应外界低温、短日照等不良环境条件的结果。茶芽打破休眠的早晚,密切关系到茶树经济生产的效益。为进一步掌握茶树芽休眠与解除的分子机理>本研究克隆了可能与黄金茶发芽早相关的转录因子(dormancy associated MADS-box CsDAM2),并在烟草中过表达CsDAM2,对CsDAM2转基因烟草和野生型烟草进行低温处理。结果表明,在相同处理条件下,随着温度的降低,同野生型烟草比较,转基因烟草电导率增加幅度小,并且叶绿素荧光值降低率低,说明在抗寒性能上,转基因烟草具有显著优势,进而一定程度上证实了 CsDAM2具有提髙茶树抗寒性的作用。本研究结果为进一步揭示茶树芽休眠与解除的分子机理提供了科学依据。 展开更多
关键词 茶树(Camellia SINENSIS L.) CsDAM2 休眠 抗寒性
Rol genes enhance content of artemisinin and other secondary metabolites in Shennong hybrid of Artemisia annua
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作者 Sara Zafar Erum Dilshad +2 位作者 Hammad Ismail Chahat Batool Rizvi Bushra Mirza 《中草药:英文版》 CAS 2019年第2期209-215,共7页
Objective: Artemisia annua is the chief source of artemisinin, a potent antimalarial agent, in which other bioactive phytochemicals are also present. Due to low levels of bioactive compounds including artemisinin and ... Objective: Artemisia annua is the chief source of artemisinin, a potent antimalarial agent, in which other bioactive phytochemicals are also present. Due to low levels of bioactive compounds including artemisinin and flavonoids, it is necessary to increase the level of the secondary metabolites by regulating the expression of rol genes in the plant.Methods: A hybrid variety of A. annua(Hyb1209 r, Shennong) developed by the Centre for Novel Agricultural Products, University of York, UK, was selected to produce transgenics of rolB and rolC genes. Genetic transformation was carried out via Agrobacterium tumefaciens GV3101 harboring rolB and rolC genes of Agrobacterium rhizogenes cloned separately. HPLC was used for the qualitative and quantitative analysis of flavonoids and artemisinin. Furthermore, thin layer chromatography(TLC) was also used to analyze artemisinin content.Results: Comparative analysis via HPLC revealed considerable enhancement in the phytochemical content of transgenic A. annua plants as compared to the wild type plant. Transgenics of rolB gene showed an average increase of 321% in rutin, 97.2% in caffeic acid, and 218.4% in myricetin, respectively. In the case of rolC gene transgenics, an average increase of 197.5% in rutin, 76.3% in caffeic acid, and 209.3%in myricetin was observed. Transgenics of rolB and rolC genes showed a 14.3%–28.6% and 2.8%–12.7% increase in artemisinin content respectively by HPLC analysis. TLC analysis showed that an average 142.2%and 110.2% enhancement in artemisinin for rolB and rolC transgenics respectively, compared with the wild type. An enhanced production of total flavonoids(average 30.2% and 25.5% increase in rolB and rolC transgenics, respectively) and total phenolics(average 34.3% and 25.8% increase in rolB and rolC transgenics, respectively) was observed as a result of transformation. Transformed A. annua plants showed improved free radical scavenging activity(average 46.5% and 29.1% increase in rolB and rolC transgenics,respectively) and total reducing po 展开更多
关键词 ARTEMISIA annua L. ARTEMISININ genetic transformation Hyb1209r ROL GENES
Screening and Analysis of Germplasm Resources of Wild Coix lacryma-jobi L. with High Content of Coixin 预览
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作者 Yubin ZHANG Xiaohong HE +3 位作者 Fanzhi LIU Qiuyi MENG Rong LIU Gang SHEN 《药用植物研究(英文版)》 2019年第2期66-68,共3页
[Objectives] To screen and analyze germplasm resources of wild Coix lacryma-jobi L. with high content of coixin.[Methods] From the 150 kinds of collected wild C. lacryma-jobi L. germplasm resources, 24 kinds of excell... [Objectives] To screen and analyze germplasm resources of wild Coix lacryma-jobi L. with high content of coixin.[Methods] From the 150 kinds of collected wild C. lacryma-jobi L. germplasm resources, 24 kinds of excellent resources were screened and detected. Morphological statistics were carried out, and the content of coixin in the four organ of roots, stems, leaves and seeds were measured, and the approved cultivar white husk Liugu of C. lacryma-jobi L. was taking as the control.[Results] Among the organs of the plant of C. lacryma-jobi L., the roots had the highest content of coixin, so the roots of C. lacryma-jobi L. can be used as the medicinal parts of C. lacryma-jobi L.[Conclusions] The wild C. lacryma-jobi L.Y229, Y164, Y166, Y83, and Y84 stains had excellent yield, and their root coixin content was significantly higher than that of the control variety, so they can be used for cultivation as excellent germplasm, so as to obtain new variety(line) of C. lacryma-jobi L.with higher content of coixin. 展开更多
关键词 COIX lacryma-jobi L. Coixin GERMPLASM resources ORGANS MEDICINAL use
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Optimization of Extraction of Saponins from Tribulus terrestris L. 预览
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作者 Quan YU Zhisheng LI +3 位作者 Yuan ZENG Chenzhong JIN Yan WANG Yihong HU 《农业生物技术:英文版》 CAS 2019年第3期162-165,168共5页
To promote the recovery of saponins from Tribulus terrestris L.,the water dissolution and ethanol precipitation method was adopted to extract saponins from the powder prepared from T.terrestris fruit.The optimal proce... To promote the recovery of saponins from Tribulus terrestris L.,the water dissolution and ethanol precipitation method was adopted to extract saponins from the powder prepared from T.terrestris fruit.The optimal process was to extract with 9 fold of the extracting water at the ethanol concentration of 85 for 3 times,each time 3.5 h.The effects of the factors ranked as the extracting water quantity > treatment time > treatment times > ethanol concentration.Under these optimal conditions,the recovery of saponins was 2.81%.After these crude saponins were purified by D101 macroporous adsorptive resin,the purity was found to be promoted through the UV scanning method,and the recovery of the refined saponins was up to 1.53%.Both of the recovery values were higher than that of the existing process. 展开更多
关键词 Tribulus terrestris L. SAPONINS ORTHOGONAL experiment RECOVERY MACROPOROUS ADSORPTIVE RESIN
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Fumigant toxicity and sublethal effects of Teucrium polium essential oil on Aphis fabae scopoli A
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作者 Sultan Ravan Abbas Khani Sedigheh Sufi 《中草药:英文版》 CAS 2019年第2期231-235,共5页
Objective: Black bean aphid(Aphis fabae) is one of the most important greenhouse and crop pests with a wide range of hosts, which causes damages through feeding on vegetable sap and transmitting viral diseases. Curren... Objective: Black bean aphid(Aphis fabae) is one of the most important greenhouse and crop pests with a wide range of hosts, which causes damages through feeding on vegetable sap and transmitting viral diseases. Currently, chemical methods are mainly used to control this pest. Considering the adverse effects of pesticides, it is essential to apply less chemical pesticide in pest control programs. The lethal and sublethal effects of the essential oil(EO) of Teucrium polium leaves on one-day-old adults of black bean aphid were investigated under laboratory conditions.Method: The bioassay was evaluated at the concentrations of 0.88-12 μL/L air, for 24 h after treatment.Reproductive life table parameters of new emerged aphid surveyed at sub-lethal concentrations(LC20 and LC40) of EO and the biological reproductive table was calculated by Jackknife method.Results: The mortality rate increased significantly with the increasing of EO concentration. The estimated LC50 value was 4.5 μL/L air. Laboratory exposure to sublethal concentrations of EO caused significant decrease in adult female longevity and fertility of surviving aphids and as a result caused significant reduction in the intrinsic rate of natural increase(rmvalue).Conclusion: The results of this study revealed that EO of T. polium could be used as a potential control agent for the aphid. 展开更多
关键词 black BEAN APHID FUMIGANT toxicity HERBAL essential oil SUBLETHAL effect TEUCRIUM polium L.
Studies on the Analgesic Activity and Acute Toxicities of Bidens alba (L.) DC 预览
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作者 Minggui YUAN Qiyun GAO +4 位作者 Rong XIANG Ting HUANG Danni YU Zhihong XU Xinyu PENG 《农业生物技术:英文版》 CAS 2019年第3期174-176,共3页
[Objectives]This study was conducted to investigate the analgesic effects and acute toxicities of Bidens alba (L.) DC.[Methods]The alcohol extract of B.alba (L.) DC was extracted and separated with petroleum ether and... [Objectives]This study was conducted to investigate the analgesic effects and acute toxicities of Bidens alba (L.) DC.[Methods]The alcohol extract of B.alba (L.) DC was extracted and separated with petroleum ether and chloroform successively.The acute toxicities of the two extracts on mice were measured,and then the analgesic effects were measured with writhing pain model induced by acetic acid.[Results]No mice died when the crude dosages of B.alba (L.) DC from petroleum ether extract and chloroform extract were 5 016 and 5 100 mg/kg,respectively.When the petroleum ether extract was 60.0 mg/kg,the percentage of twisted mice induced by acetic acid was 40%,the analgesic rate was 77.5%,and the time of the first writhing was (294.0±165.8) s;when the chloroform extract was 20.0 mg/kg,the percentage of twisted animals was 55.6%,the analgesic rate was 51.5%,and the time of the first writhing was (273.8 ±153.4) s;and when the chloroform extract was 4.0 mg/kg,the percentage of twisted animals was 40%,and the analgesic rate was 62.1%,and the time of the first writhing was (370.6±231.3) s.[Conclusions]The petroleum ether extracts and chloroform extracts of B.alba (L.) DC have good analgesic effects and no acute toxicities. 展开更多
关键词 BIDENS ALBA (L.) DC Mouse Analgesic effect ACUTE toxicity Petroleum ether CHLOROFORM
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Adjustment of Mathematical Models and the Quality of Drying the Pulped Coffee at Different Air Conditions 预览
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作者 Paulo Carteri Coradi Reni Saath +1 位作者 Carlos Henrique Reinato Flávio Meira Borém 《农业科学与技术:B》 2019年第1期38-48,共11页
The aim of the study was to describe the drying kinetics of washed coffee (Coffea arabica L.) and evaluate the best mathematical model to fit the experimental drying data conducted with different air humidity (40%, 50... The aim of the study was to describe the drying kinetics of washed coffee (Coffea arabica L.) and evaluate the best mathematical model to fit the experimental drying data conducted with different air humidity (40%, 50% and 60%), temperatures (23, 40 and 60 °C) and the quality of the coffee. The cherries coffee were separated and standardized in the processes of washing, mechanical and manual separation. Then, approx. 85 kg of coffee cherries were pulped and taken directly to the yard. The washed coffee was completed dried in a mechanical dryer and yard. The results showed that the different conditions of the ambient air significantly influenced the processes of drying. The water content of the hygroscopic equilibrium of pulped coffee is directly proportional to the water activity and relative humidity (RH), decreasing with increasing temperature, for the same value of equilibrium. The Oswin model was best represented by the hygroscopicity of the pulped coffee, while the Midilli model shows the best fit to describe the drying curves of the washed coffee. The effective diffusion coefficient increases with increasing temperature of the drying air and reducing of RH, being described by the Arrhenius equation. Electrical conductivity, potassium leaching, total titratable acidity and grease acidity increase with increasing drying temperature regardless of the type of processing. Reducing sugars, total sugars and the sensorial quality was negatively affected with increasing drying temperature regardless of the type of processing. The drying at 60 °C/40% RH negatively affected the coffee quality. 展开更多
关键词 COFFEA arábica L. drying MATHEMATICAL MODELING pulped coffee.
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Large scale identification of SSR marker in perilla by next generation sequencing 预览
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作者 Qi Shen He Wen +5 位作者 Tianyuan Zhang Jing Xu Xianping Wang Shimei Yang Caifu Du Degang Zhao 《Oil Crop Science-中国油料作物学报英文版》 2019年第2期100-109,共10页
Perilla frutescens (L.) is an edible, medicinal crop, and most popular in East Asia. Its molecular breeding and research are hampered by the paucity of molecular markers. Simple sequence repeat (SSR) markers are ubiqu... Perilla frutescens (L.) is an edible, medicinal crop, and most popular in East Asia. Its molecular breeding and research are hampered by the paucity of molecular markers. Simple sequence repeat (SSR) markers are ubiquitous and widely used in eukaryotic genomes. EST-SSRs identification of perilla was performed in 116,387 reads generated by Illumina paired-end sequencing technology. In total 25,449 unigenes containing SSR and 33,867 SSR loci were identified, and 19,400 primer pairs were designed. Polymorphism of SSR primers was conducted by searching for insertions and deletions (INDELs), and 1,567 unique SSRs were predicted. Totally, 200 SSR primer pairs were selected for polymorphic validation among 23 perilla accessions. Results showed that 175 primer pairs produced amplicons, and 30 pairs exhibited polymorphism. Polymorphic ratio was higher by using INDEL method than using conventional primers. Phylogenetic analysis showed the 2 distinct groups: P. frutescens var. frutescens and P. frutescens var. crispa. Wrinkled leaf trait and seed trait were distinct between these 2 groups. However, no clear leaf color or geographic relationship was detected. The large scale development and identification of SSR marker in this research laid a foundation for genetic analysis and marker assisted breeding of cultivated perilla. 展开更多
关键词 PERILLA frutescens L. simple sequence REPEATS (SSR) NEXT generation SEQUENCING INDEL marker-assisted BREEDING
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Genetic dissection of root morphological traits as related to potassium use efficiency in rapeseed under two contrasting potassium levels by hydroponics
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作者 Xiaoling Dun Jiaqin Shi +3 位作者 Huiping Liu Jie Wang Xinfa Wang Hanzhong Wang 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第6期746-757,共12页
To reveal the genetic basis of potassium use efficiency(KUE) in rapeseed, root morphology(RM), biomass and KUE-related traits were measured in a recombinant inbred line population with 175 F7 lines that were subjected... To reveal the genetic basis of potassium use efficiency(KUE) in rapeseed, root morphology(RM), biomass and KUE-related traits were measured in a recombinant inbred line population with 175 F7 lines that were subjected to high-potassium(HK) and low-potassium(LK) treatments by hydroponics. A total of 109 significant QTLs were identified to be associated with the examined traits. Sixty-one of these QTLs were integrated into nine stable QTLs. The higher heritability for RM and biomass traits and lower heritability for KUE-related traits, as well as nine stable QTLs for RM traits and only two for KUE-related traits,suggested that regulating RM traits would be more effective than selecting KUE traits directly to improve KUE by markerassisted selection. Furthermore, the integration of stable QTLs identified in the HK, LK, high-nitrogen(HN) and low-nitrogen(LN) conditions gave 10 QTL clusters. Seven of these clusters were classified into major QTLs that explained 7.4%–23.7% of the total phenotypic variation. Five of the major QTL clusters were detected under all of the treated conditions, and four clusters were specifically detected under the LK and LN conditions. These common and specific QTL clusters may be useful for the simultaneous improvement of multiple traits by marker-assisted selection. 展开更多
关键词 Brassica NAPUS L. ROOT traits potassium efficiency QTL mapping QTL cluster
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