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Increase in root density induced by coronatine improves maize drought resistance in North China

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The Crop Journal 2023年第1期11卷 278-290页

作者： Yuling Guo Guanmin Huang Qing Guo Chuanxi Peng Yingru Liu Mingcai Zhang Zhaohu Li Yuyi Zhou liusheng duan State Key Laboratory of Plant Physiology and Biochemistry College of Agronomy and BiotechnologyChina Agricultural UniversityBeijing 100193China

Drought stress caused by insufficient irrigation or precipitation impairs agricultural production *** this study,a two-year field experiment was conducted to investigate the effect of coronatine(COR),a functional analog of jasmonic acid(JA),on maize drought *** experiment included two water treatments(rainfed and irrigation),four COR concentrations(mock,0μmol L^(-1);A1,0.1μmol L^(-1);A2,1μmol L^(-1);A3,10μmol L^(-1))and two maize genotypes(Fumin 985(FM985),a drought-resistant cultivar and Xianyu 335(XY335),a drought-sensitive cultivar).Spraying 1μmol L^(-1)COR at seedling stage increased surface root density and size,including root dry matter by 12.6%,projected root area by 19.0%,average root density by 51.9%,and thus root bleeding sap by 28.2%under drought *** application also increased leaf area and SPAD values,a result attributed to improvement of the root system and increases in abscisic acid(ABA),JA,and salicylic acid(SA)*** improvement of leaves and roots laid the foundation for increasing plant height and dry matter *** application reduced anthesis and silking interval,increasing kernel number per *** treatment at 1μmol L^(-1)increased the yield of XY335 and FM985 by 7.9%and 11.0%,*** and path analysis showed that grain yields were correlated with root dry weight and projected root area,increasing maize drought resistance mainly via leaf area index and dry matter ***,COR increased maize drought resistance mainly by increasing root dry weight and root area,with 1μmol L-^(-1)COR as an optimal concentration.

关键词： Maize Drought resistance Coronatine Root development Grain yields

Coronatine promotes maize water uptake by directly binding to the aquaporin ZmPIP2;5 and enhancing its activity

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Journal of Integrative Plant Biology 2023年第3期65卷 703-720页

作者： Rui He Huiqing Su Xing Wang Zhijie Ren Kun Zhang Tianyu Feng Mingcai Zhang Zhaohu Li Legong Li Junhong Zhuang Zhizhong Gong Yuyi Zhou liusheng duan State Key Laboratory of Plant Physiology and Biochemistry Engineering Research Center of Plant Growth RegulatorMinistry of Education&College of Agronomy and BiotechnologyChina Agricultural UniversityBeijing 100193China College of Plant Protection China Agricultural UniversityBeiing 100193China Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement Beijing Municipal GovernmentCollege of Life SciencesCapital Normal UniversityBeijing 100048China Center for Crop Functional Genomics and Molecular Breeding China Agricultural UniversityBeijing 100193China State Key Laboratory of Plant Physiology and Biochemistry College of Biological SciencesChina Agricultural UniversityBeijing 100193China

Water uptake is crucial for crop growth and development and drought stress tolerance. The water channel aquaporins(AQP) play important roles in plant water uptake. Here, we discovered that a jasmonic acid analog, coronatine(COR), enhanced maize(Zea mays) root water uptake capacity under artificial water deficiency conditions. COR treatment induced the expression of the AQP gene Plasma membrane intrinsic protein 2;5(ZmPIP2;5).In vivo and in vitro experiments indicated that COR also directly acts on ZmPIP2;5 to improve water uptake in maize and Xenopus oocytes. The leaf water potential and hydraulic conductivity of roots growing under hyperosmotic conditions were higher in ZmPIP2;5-overexpression lines and lower in the zmpip2;5 knockout mutant, compared to wild-type plants. Based on a comparison between ZmPIP2;5 and other PIP2s, we predicted that COR may bind to the functional site in loop E of ZmPIP2;5. We confirmed this prediction by surface plasmon resonance technology and a microscale thermophoresis assay, and showed that deleting the binding motif greatly reduced COR binding. We identified the N241 residue as the COR-specific binding site, which may activate the channel of the AQP tetramer and increase water transport activity,which may facilitate water uptake under hyperosmotic stress.

关键词： coronatine osmotic stress water uptake capacity ZmPIP2 5

Variations in Growth, Photosynthesis and Defense System Among Four Weed Species Under Increased UV-B Radiation

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Journal of Integrative Plant Biology 2007年第5期49卷 621-627页

作者： Shiwen Wang liusheng duan Anthony Egrinya Eneji Zhaohu Li State Key Laboratory of Plant Physiology and Biochemistry Centre of Crop Chemical Control Department of Agronomy China Agricultural University Beijing 100094 China

Weed tolerance of UV-B radiation varies with species, and the radiation could affect weed ecology and management. Variations In growth, photosynthesis and defense system among four important agronomic weeds, Abutllon theophrastl Medlk, Amaranthus retroflexus L., Digitaria sanguinalis （L.） Scop and Chloris virgata Swartz, under Increased UV-B radiation （ambient and increased radiation at 2.7, 5.4 and 10.8 kJ.m^-2.d-1） were studied In the greenhouse experiment. After 2 weeks of radiation, the shoots＇ dry mass decreased with increasing UV-B radiation except for D. sanguinalis. The reduction in biomass was the result of changes in morphology and physiology. Higher levels of UV-B treatment decreased the leaf area, plant height, net photosynthetic rate and chlorophyll contents, while it increased the contents of wax and UV-B absorbing compound in all species, except for A. retroflexus, which did not increase significantly. The activity of superoxide dismutase, catalase, ascorbate peroxide and the content of ascorblc acid changed differently among the weed species as UV-B radiation increased. D. sangulnalls was the most tolerant and A. retroflexus the most sensitive to increased UV-B radiation. The results also show that the two grass species （D. sanguinalis and C. virgata） were more tolerant to UV-B radiation than the two broadleafed species （A. theophrasti and A. retroflexus）. The UV-B absorbing compound and leaf wax played Important roles against UV-B damages in the two grass weeds. The overall results suggest that weed community, competition and management will be altered by continuous ozone depletion.

关键词： crabgrass fingergrass leaf wax redroot UV-B absorbing compounds UV-B radiation velvetleaf

Analysis of differential expression of genes induced by ethephon in elongating internodes of maize plants

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Frontiers of Agricultural Science and Engineering 2016年第3期3卷 263-282页

作者： Xiaoyi WEI Weiqiang ZHANG Qian ZHANG Pei SUN Zhaohu LI Mingcai ZHANG Jianmin LI liusheng duan State Key Laboratory of Plant Physiology and Biochemistry Engineering Research Center of Plant Growth Regulator Ministry of Education/College of Agronomy China Agricultural University Xinxiang Academy of Agricultural Science

Plant growth regulators(PGRs) are commonly used in cereal cropping systems to restrict plant height and control lodging. Ethephon has been reported to shorten internodes and increase grain yield of maize. To analyze the transcriptomic profiles of maize internode elongation following ethephon treatment, differentially expressed genes were compared between the treatment and contro samples of inbred line Zong 31 using the Affymetrix Maize Genome Array. According to the microarray data 326 probe sets showed significant change in expression Further research revealed that the most remarkable effects of ethephon on maize internodes elongation occurred during a 48 h period, when 89 differentially expressed genes were detected. There were dramatic change in transcript levels at 24 h and six Auxin transport genes and four gibberellin biosynthesis pathway genes were differentially expressed in Zong 31 in response to ethephon treatment. In summary, we showed that gaseous ethylene release is involved in internode meristem cell elongation through the regulation of plant hormone signaling in maize. This work provides a platform for studies in which candidate genes will be functionally tested for involvement in internode elongation.

关键词： maize ethephon internode elongation microarray qPCR

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高强钢板组合螺栓抗拉性能有限元分析

哈尔滨工业大学学报 2020年第10期52卷 102-110页

作者：段留省夏瑞林周天华长安大学建筑工程学院西安710061

高强钢板钻孔攻丝后替代螺母,与高强螺杆组合成一种新的单边螺栓连接副,可用于钢管柱框架节点.为研究钢板组合螺栓抗拉承载力和破坏机理,在本组试验研究的基础上对4类钢板组合螺栓共64个试件进行单调拉伸数值模拟,以板厚和螺杆直径为研... 详细信息

高强钢板钻孔攻丝后替代螺母,与高强螺杆组合成一种新的单边螺栓连接副,可用于钢管柱框架节点.为研究钢板组合螺栓抗拉承载力和破坏机理,在本组试验研究的基础上对4类钢板组合螺栓共64个试件进行单调拉伸数值模拟,以板厚和螺杆直径为研究变量,包括Q345B、45号钢、Q460C和Q690D四种钢材和10.9级M16、M20、M24、M27和M30五种规格高强螺栓.结果表明:Q345B、Q460C和Q690D均可作为45号钢的替代材料;钢板组合螺栓在锚固可靠的条件下,可按螺杆螺纹极限抗拉荷载的70%作为其抗拉设计值;钢板较薄时,发生钢板螺纹滑牙破坏,螺栓拔出,螺杆最大应力位于锚固区,钢板向外凸起,凸起量大于支点间距的1/200;钢板较厚时,发生螺杆拉断破坏,螺杆最大应力位于构造区,两种破坏模式中钢板的最大应力均位于钢板螺纹第一扣处.为保证钢板组合螺栓不发生钢板螺纹滑牙破坏,建议Q345B钢板厚度不宜低于1.15 d;Q460C钢板厚度不宜低于1.10 d;Q690D钢板厚度不宜低于0.95 d,根据弹性力学和螺纹传力机理推导高强钢板组合螺栓抗拉承载力公式,公式计算结果与有限元结果吻合良好,研究成果可为钢板组合螺栓的设计提供参考.

关键词：单边螺栓钢板攻丝应力分布厚径比破坏模式螺纹

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高强钢组合K形偏心支撑钢框架抗震性能分析

西安建筑科技大学学报（自然科学版） 2015年第1期47卷 46-50,61页

作者：段留省苏明周长安大学建筑工程学院陕西西安710061 西安建筑科技大学土木工程学院陕西西安710055 西部建筑科技国家重点实验室(筹) 陕西西安710055

偏心支撑钢框架设计时需要通过内力放大系数调整梁柱截面以抵抗耗能梁段的应变硬化效应,导致用钢量增大和节点连接困难.根据"相对强弱"的抗震思想,可将高强度钢材引入基本处于弹性的钢框架部分,耗能梁段采用屈服点较低钢材,形成高强钢... 详细信息

偏心支撑钢框架设计时需要通过内力放大系数调整梁柱截面以抵抗耗能梁段的应变硬化效应,导致用钢量增大和节点连接困难.根据"相对强弱"的抗震思想,可将高强度钢材引入基本处于弹性的钢框架部分,耗能梁段采用屈服点较低钢材,形成高强钢组合偏心支撑钢框架.为研究这种新型结构的抗震性能和用钢量优势,采用ANSYS对2榀单层剪切屈服机制的K形偏心支撑钢框架进行了非线性有限元分析,其中考虑材料非线性和几何非线性.结果表明在相同应力比设计原则下,对同一耗能梁段采用高强钢框架可以节省约14%的用钢量,而抗震性能与普通偏心支撑钢框架相当.

关键词：高强钢偏心支撑抗震性能用钢量非线性有限元

高强钢芯筒-螺栓连接钢管柱节点静力性能试验

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哈尔滨工业大学学报 2019年第12期51卷 172-179页

作者：段留省周天华苏明周长安大学建筑工程学院西安710061 西安建筑科技大学土木工程学院西安710055

为解决现有钢管柱节点单边螺栓锚固不足和操作复杂的问题,提出高强钢芯筒-螺栓连接副装配式节点,连接副由内置于钢管柱的高强钢芯筒和常规高强螺栓组成.为考察这种新型节点的静力性能,对6个1∶1足尺钢管柱框架边节点进行单调加载试验,... 详细信息

为解决现有钢管柱节点单边螺栓锚固不足和操作复杂的问题,提出高强钢芯筒-螺栓连接副装配式节点,连接副由内置于钢管柱的高强钢芯筒和常规高强螺栓组成.为考察这种新型节点的静力性能,对6个1∶1足尺钢管柱框架边节点进行单调加载试验,研究变量为钢芯筒类型、筒壁厚度、螺栓直径、钢梁端板厚度.重点分析节点关键部位的应力变化、变形能力、破坏模式、螺栓拉力和节点类型.结果表明:试件均为半刚性节点、梁端塑性铰破坏机制,封闭型芯筒厚度与螺栓直径相当时可以满足梁柱刚接的强度条件;节点域变形很小可以忽略,芯筒转动变形对节点转动影响不超过10%;钢梁端板与柱的间隙随着芯筒厚度减小而快速增长,螺栓有拔出趋势,连接副的抗拉设计值可按钢板螺纹抗拉承载力的70%取用.

关键词：单边螺栓节点转动能力螺栓拉力破坏模式节点类型

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虎杖叶绿体基因组结构与变异分析

生物工程学报 2022年第5期38卷 1953-1964页

作者：孙孟涛张峻鑫黄体冉杨明峰马兰青段留生北京农学院林木分子设计育种高精尖创新中心北京102206 农业农村部华北都市农业重点实验室北京102206 中国科学院大学生命科学学院北京100049 北京农学院植物科学技术学院北京102206

虎杖(Reynoutria japonica Houtt.)为蓼科(Polygonaceae)蓼族(Polygoneae)虎杖属(Reynoutria Houtt.)植物,是一种传统的中草药,具有利湿退黄、清热解毒、散瘀止痛、止咳化痰的功效。本研究采取高通量测序技术获得5个虎杖品种的叶绿体全... 详细信息

虎杖(Reynoutria japonica Houtt.)为蓼科(Polygonaceae)蓼族(Polygoneae)虎杖属(Reynoutria Houtt.)植物,是一种传统的中草药,具有利湿退黄、清热解毒、散瘀止痛、止咳化痰的功效。本研究采取高通量测序技术获得5个虎杖品种的叶绿体全基因组序列,并与NCBI已公布的蓼族何首乌(Fallopia multiflora)和金线草(Antenoron filiforme)等植物的叶绿体全基因组序列进行了基因组学和系统发育分析。通过基因组学分析发现,5种虎杖的叶绿体基因组大小有163 376 bp和163 371 bp两种情况,并呈现出典型的环状四分体结构,85 784 bp的一条较长的单拷贝区(large single-copy region,LSC),18 616 bp的一条较短的单拷贝区(small single-copy region,SSC),还有两条长度一致的反向重复区,分别为IRa区和IRb区相间隔分布。通过注释得到161个基因,其中蛋白编码基因106个,rRNA编码基因10个,tRNA编码基因45个。总GC含量为36.7%,其中LSC、SSC和IR区域的GC含量分别为34.8%、30.7%和42.7%。对比不同虎杖品种叶绿体的全基因组分析发现,trnk-UUU、rpoC1、petD、rpl16、ndhA、rpl12基因的编码区发生了变异。系统发育分析显示,虎杖5个品种聚为一枝,处在已知11种蓼族材料最原始的位置,与何首乌构成姐妹群。

关键词：中草药叶绿体全基因组基因组学分析环状四分体

高强钢组合Y形偏心支撑钢框架抗震性能试验研究

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建筑结构学报 2014年第7期35卷 89-96页

作者：段留省苏明周焦培培郝麒麟西安建筑科技大学结构与抗震教育部重点实验室陕西西安710055

高强钢组合Y形偏心支撑钢框架是耗能梁段采用较低屈服点钢材、其他构件采用高强钢的双重抗侧力结构体系。为研究其抗震性能,对4个1∶2缩尺的单层单跨高强钢组合Y形偏心支撑钢框架平面试件进行了单调和循环加载试验。根据耗能梁段长度将... 详细信息

高强钢组合Y形偏心支撑钢框架是耗能梁段采用较低屈服点钢材、其他构件采用高强钢的双重抗侧力结构体系。为研究其抗震性能,对4个1∶2缩尺的单层单跨高强钢组合Y形偏心支撑钢框架平面试件进行了单调和循环加载试验。根据耗能梁段长度将试件分为剪切屈服型和弯曲屈服型两类,分别研究了每类试件的破坏模式和主要抗震性能指标。研究结果表明,该结构耗能能力强、延性好,剪切屈服型试件的承载力比弯曲屈服型试件的高,延性也好于后者,相同位移下耗散的能量也较后者大。循环加载时,剪切屈服型试件的破坏集中于耗能梁段,此时钢框架基本处于弹性工作状态,残余变形较小,是一种有利于震后修复的双重抗侧力体系。

关键词：高强钢框架 Y形偏心支撑耗能梁段单调加载循环加载抗震性能