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Growth and abscisic acid responses of

Yue LI, Liqiang WAN, Yufei WANG, Xianglin LI

《农业科学与工程前沿（英文）》 2018年第5卷第1期页码 80-86 doi: 10.15302/J-FASE-2017199

摘要： A pot experiment was conducted in a greenhouse with three alfalfa ( ) cultivars, Aohan, Zhongmu No.1 and Sanditi, to examine the morphological and physiological responses of alfalfa to water stress. The response of alfalfa to water stress at different growth stages was generally similar, but varied among cultivars. At the branching, flowering and podding stages, the shoot biomasses of Aohan and Zhongmu No.1 were greatly affected by, and responded quickly to, water stress. The shoot biomass of Sanditi was not affected by mild water stress, but had a slight response to moderate and severe water stress. The root/shoot ratios in Aohan and Zhongmu No.1 were more sensitive to water stress than in Sanditi, with the root/shoot ratio in Aohan increasing most significantly. At flowering, the root/shoot ratio was the highest and the effect of water stress the greatest. The abscisic acid (ABA) concentration in the roots of Aohan and Zhongmu No.1 increased under water stress, while in Sanditi there was only a slight or delayed response of ABA concentration.

关键词： abscisic acid alfalfa drought response growth stage water deficit

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APPLE SUMO E3 LIGASE MDSIZ1 NEGATIVELY REGULATES DROUGHT TOLERANCE

《农业科学与工程前沿（英文）》 2021年第8卷第2期

摘要：

Drought stress typically causes heavy losses in apple production and uncovering the mechanisms by which apple tolerates drought stress is important in apple breeding. MdSIZ1 is a SUMO (small ubiquitin-like modifier) E3 ligase that promotes SUMO binding to substrate proteins. Here, we demonstrate that MdSIZ1 in apple has a negative relationship with drought tolerance. MdSIZ1 RNAi transgenic apple trees had a higher survival rate after drought stress. During drought stress they had higher leaf water potential, reduced ion leakage, lower H₂O₂ and malondialdehyde contents, and higher catalase activity. In addition, MdSIZ1 RNAi transgenic plants had a higher net photosynthetic rate during the latter period of drought stress. Finally, the transgenic apple trees also altered expression levels of some microRNAs in response to drought stress. Taken together, these results indicate that apple MdSIZ1 negatively regulates drought stress by enhancing leaf water-holding capacity and antioxidant enzyme activity.

关键词： apple / drought tolerance / gene expression / MdSIZ1

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APPLE SUMO E3 LIGASE MDSIZ1 NEGATIVELY REGULATES DROUGHT TOLERANCE

Baohua CHU, Jia SUN, Huan DANG, Ziqing MA, Shuang ZHAO, Qingmei GUAN, Xuewei LI

《农业科学与工程前沿（英文）》页码 247-261 doi: 10.15302/J-FASE-2021388

摘要： Drought stress typically causes heavy losses in apple production and uncovering the mechanisms by which apple tolerates drought stress is important in apple breeding. MdSIZ1 is a SUMO (small ubiquitin-like modifier) E3 ligase that promotes SUMO binding to substrate proteins. Here, we demonstrate that in apple has a negative relationship with drought tolerance. RNAi transgenic apple trees had a higher survival rate after drought stress. During drought stress they had higher leaf water potential, reduced ion leakage, lower H O and malondialdehyde contents, and higher catalase activity. In addition, RNAi transgenic plants had a higher net photosynthetic rate during the latter period of drought stress. Finally, the transgenic apple trees also altered expression levels of some microRNAs in response to drought stress. Taken together, these results indicate that apple MdSIZ1 negatively regulates drought stress by enhancing leaf water-holding capacity and antioxidant enzyme activity.

关键词： apple drought tolerance gene expression MdSIZ1

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农业防旱抗旱减灾工程技术与应用

李玉中,王春乙,程延年

《中国工程科学》 2012年第14卷第9期页码 85-89

摘要：

介绍了干旱以及干旱对作物的影响，概述了农业防灾减灾的主要工程措施，这些工程措施包括集水工程、蓄水工程、覆盖抑蒸工程、节水灌溉工程、人工增雨防旱工程、抗旱种衣剂包衣工程，并介绍了这些工程的应用效果。

关键词：农业干旱工程减灾抗旱种衣剂包衣工程

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Functional trait differences between native bunchgrasses and the invasive grass

Huiqin HE, Thomas A. MONACO, Thomas A. JONES

《农业科学与工程前沿（英文）》 2018年第5卷第1期页码 139-147 doi: 10.15302/J-FASE-2017175

摘要： We conducted 30- and 60-d greenhouse experiments to compare functional traits of (invasive annual grass) and four perennial bunchgrasses under well-watered or drought conditions. Even under drought, experienced significantly less stress (i.e., higher xylem pressure potential and greater shoot water content, water use per day and water-use efficiency) and biomass production than the perennial grasses after 30 d. However, after 60 d, its superiority was reduced under infrequent watering. Differences among perennial grasses were more pronounced for physiological traits under infrequent watering and for morphological traits under frequent watering. (fast-growing species) had a higher transpiration rate, lower leaf temperature, and lower water-use efficiency than the other grasses after 30 d. In contrast, (slow-growing) had lower xylem pressure potential and higher leaf temperature than all other grasses under infrequent watering. Under frequent watering, shoot dry mass and specific leaf area of was matched by (moderate-growing species). Our results indicate that multiple-species plantings or seedings are necessary to foster greater weed resistance against . We also emphasize that when choosing plant material for restoration, performance during both pulse (resource-rich) and inter-pulse (resource-poor) periods should be considered.

关键词： annual grass comparative growth drought response invasive plant native grass specific leaf area soil-water use

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APPLE SUMO E3 LIGASE MDSIZ1 NEGATIVELY REGULATES DROUGHT TOLERANCE

《农业科学与工程前沿（英文）》 2021年第8卷第4期页码 662-662 doi: 10.15302/J-FASE-2021408

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OVEREXPRESSION OF PTRLEA7, A LATE EMBRYOGENESIS ABUNDANT FAMILY GENE FROM PONCIRUS TRIFOLIATA, CONFERS ENHANCED DROUGHT

《农业科学与工程前沿（英文）》 2021年第8卷第2期

摘要：

Late embryogenesis abundant (LEA) genes encode highly hydrophilic proteins that are essential in abiotic stress responses. However, most LEA genes in higher plants have not yet been investigated. This study identified an LEA family gene (PtrLEA7) from Poncirus trifoliata and studied its function in drought tolerance. The full-length coding sequence of PtrLEA7 was 420 bp encoding a protein of 139 amino acids. Phylogenetic analysis shows that PtrLEA7 protein belongs to the LEA_4 subfamily. Expression profiling by qPCR found that PtrLEA7 was strongly induced by dehydration, cold and ABA treatments, and slightly induced by salt stress. Subcellular localization reveals that PtrLEA7 protein was located in both cytoplasm and nucleus. To investigate its function, transgenic plants of both tobacco and Poncirus trifoliata overexpressing PtrLEA7 were obtained. Stress tolerance assays show that overexpression lines had enhanced dehydration and drought tolerance compared with wild type plants, indicating that PtrLEA7 positively regulates drought tolerance. In addition, transgenic plants had much higher expression levels of three antioxidant enzyme genes (CAT, SOD and POD) and significantly increased catalase enzyme activity, accompanied by reduced reactive oxygen species accumulation in comparison with wild type plants. Collectively, this study demonstrates that PtrLEA7 can confer enhanced drought tolerance partially via enhancing antioxidant capacity.

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2008年冬季—2009年春季干旱的大气结构与地球转动特征

魏鸣,欧阳首承

《中国工程科学》 2011年第13卷第1期页码 49-55

摘要：

针对干旱预测的难题，利用揭示大气热结构垂直特征的V-3θ图，分析影响旱区的气流特征。根据国际地球自转服务（IERS）的数据，分析地球极移、章动和转速的变化与大气热结构变化的关系，基于地气动量守恒原理，将大气热结构与地球转动特征变化进行了制约性分析。结果表明，大气热结构异常和地球转动特征引起的冷空气路径变化与大范围干旱有关。

关键词：干旱冷空气路径回流章动极移

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地球的章动和转速与副热带高压和高温干旱

魏鸣,欧阳首承

《中国工程科学》 2007年第9卷第8期页码 40-46

摘要：

鉴于近10多年来运用地球转速的变化做长期灾害天气预测取得的较好效果，试图运用地球的章动、地球转速和大气变化的关系，探索重大灾害天气的深层次原因。仅就2006年发生在四川、重庆的高温干旱问题，讨论了副热带高压与东风层的关系，进而对地球的章动、转速的变化做了对比分析。结果显示，地球大气的重要灾害天气的发生，不只限于大气本身的原因，而确有可用于天气预测的星体运行的变化信息。

关键词：章动地球转速副热带高压逆滚流下沉干旱

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OVEREXPRESSION OF

Tonglu WEI, Dalong GUO, Jihong LIU

《农业科学与工程前沿（英文）》页码 236-246 doi: 10.15302/J-FASE-2020368

摘要： Late embryogenesis abundant (LEA) genes encode highly hydrophilic proteins that are essential in abiotic stress responses. However, most LEA genes in higher plants have not yet been investigated. This study identified an LEA family gene (PtrLEA7) from Poncirus trifoliata and studied its function in drought tolerance. The full-length coding sequence of PtrLEA7 was 420 bp encoding a protein of 139 amino acids. Phylogenetic analysis shows that PtrLEA7 protein belongs to the LEA_4 subfamily. Expression profiling by qPCR found that PtrLEA7 was strongly induced by dehydration, cold and ABA treatments, and slightly induced by salt stress. Subcellular localization reveals that PtrLEA7 protein was located in both cytoplasm and nucleus. To investigate its function, transgenic plants of both tobacco and Poncirus trifoliata overexpressing PtrLEA7 were obtained. Stress tolerance assays show that overexpression lines had enhanced dehydration and drought tolerance compared with wild type plants, indicating that PtrLEA7 positively regulates drought tolerance. In addition, transgenic plants had much higher expression levels of three antioxidant enzyme genes (CAT, SOD and POD) and significantly increased catalase enzyme activity, accompanied by reduced reactive oxygen species accumulation in comparison with wild type plants. Collectively, this study demonstrates that PtrLEA7 can confer enhanced drought tolerance partially via enhancing antioxidant capacity.

关键词： abiotic stress antioxidant drought late embryogenesis abundant Poncirus trifoliata

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干旱和复水对冬小麦光合产物分配格局的影响

谷艳芳,丁圣彦,高志英,邢倩

《中国工程科学》 2012年第14卷第3期页码 59-64

摘要：

于2005—2006年在中国科学院封丘农田生态实验站研究了不同水分处理下冬小麦光合产物分配格局及其动态。实验设全生育期干旱处理和充分供水处理以及干旱后拔节期、孕穗期、开花期复水处理。结果显示：不同生育期复水对冬小麦由于干旱胁迫引起的生物量下降有补偿作用；干旱和复水能改变器官水平上光合产物的分配格局；干旱胁迫引起叶、穗分配降低，并使茎、叶鞘和根分配指数上升；拔节期复水使叶光合产物分配指数增加、茎分配指数下降；孕穗期和开花期复水能提高光合产物在茎和穗中的分配；不同时期复水对干旱胁迫引起的产量下降均有不同程度的补偿作用，拔节期复水主要提高小麦单株穗数、孕穗期和开花期复水以提高千粒重为主。

关键词：光合产物分配指数可溶性糖冬小麦干旱和复水

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HOW MULTISPECIES INTERCROP ADVANTAGE RESPONDS TO WATER STRESS: A YIELD-COMPONENT ECOLOGICAL FRAMEWORK AND ITS EXPERIMENTAL APPLICATION

《农业科学与工程前沿（英文）》 2021年第8卷第3期页码 416-431 doi: 10.15302/J-FASE-2021412

摘要：

Absolute yield and land use efficiency can be higher in multicrops. Though this phenomenon is common, it is not always the case. Also, these two benefits are frequently confused and do not necessarily occur together. Cropping choices become more complex when considering that multicrops are subject to strong spatial and temporal variation in average soil moisture, which will worsen with climate change. Intercropping in agroecosystems is expected to buffer this impact by favoring resistance to reduced humidity, but there are few empirical/experimental studies to validate this claim. It is not clear if relatively higher multicrop yield and land use efficiency will persist in the face of reduced soil moisture, and how the relation between these benefits might change. Here, we present a relatively simple framework for analyzing this situation. We propose a relative multicrop resistance (RMR) index that captures all possible scenarios of absolute and relative multicrop overyield under water stress. We dissect the ecological components of RMR to understand the relation between higher multicrop yield and land use efficiency and the ecological causes of different overyield scenarios. We demonstrate the use of this framework with data from a 128 microplot greenhouse experiment with small annual crops, arranged as seven-species multicrops and their corresponding monocrops, all under two contrasting watering regimes. We applied simple but robust statistical procedures to resulting data (based on bootstrap methods) to compare RMR, and its components, between different plants/plant parts. We also provide simple graphical tools to analyze the data.

关键词： agroecosystem sustainability crop overyielding intercrop drought resistance overyield ecological components

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Development of a seismic design method based on response spectra for building structures

ZHOU Xiyuan, YU Ruifang

《结构与土木工程前沿（英文）》 2007年第1卷第2期页码 129-141 doi: 10.1007/s11709-007-0014-2

摘要： The assumption and problem of the mode-superposition response spectrum method in seismic design code is discussed based on a brief review of the development of the seismic design method for building structures. The scope of application for the classical damping theory is analyzed and the necessity of the research on mode-superposition method for non-classical damping is presented. The progresses on the mode superposition response spectrum theory are discussed. This includes: 1) the complex mode superposition method (in real form) for the non-classically damped linear system and the general calculation formula for the application of code; 2) the complex complete quadratic combination (CCQC) method for the non-classically damped linear system, which is based on the same assumptions as in deducing the complete quadratic combination (CQC) method which is popularly used in seismic design codes of many countries; 3) the complex complete quadratic combination with three components (CCQC3) method, which is a generalization of the CCQC method to the case of multi-components and multiple-support seismic excitations and deducing corresponding method; 4) the approach for calculation of seismic response of the non-classically damped system with overcritical damping and the calculation method of seismic response for the linear system with multiple eigenvalues; 5) the time-dependent CCQC (t) algorithm considering nonstationary earthquake ground motion; 6) an applied and effective method to solve the low order complex vector basis for the large linear non-classically damped system, which can be expediently used in practice to avoid the unknown errors coming from the forced uncoupling method; 7) bringing forward the concept of partial quadratic combination in order to reduce the calculation amount of CQC and CCQC methods, and studying the primary estimation-criterion. The reasonability and applicable scope of these methods are also briefly discussed in this paper.

关键词： generalization classical damping mode-superposition response calculation formula damping theory

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Confining pressure effect on dynamic response of high rockfill dam

Xuexing CAO, Yunlong HE, Kun XIONG,

《结构与土木工程前沿（英文）》 2010年第4卷第1期页码 116-126 doi: 10.1007/s11709-010-0014-5

摘要： Studies show that the dynamic properties of rockfill are strongly dependent on the confining pressure. Therefore, confining pressure effect has become a very important factor in the seismic analysis of high rockfill dam. The relationships of dynamic shear modulus versus dynamic shear strain and damping ratio versus dynamic shear strain had been improved to a certain degree on the basic of widely used Hardin-Drnevich constitutive model in this paper. Then a new model that could consider confining pressure effect has been established. Regression analysis was carried out of the dynamic triaxial experimental data of the damming materials in the Changheba hydropower station of Sichun Province, China. The results show that, the new model can fit the test data well under various confining pressures. A corresponding computational procedure was compiled and applied in the dynamic response analysis of the Changheba Dam. Comparing the calculation results between the new constitutive model and the ordinary Hardin-Drnevich model, it can be seen that the result is conservative to some extent without considering confining pressure effect.

关键词： confining pressure effect high rockfill dam dynamic response Hardin-Drnevich constitutive model

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Topology optimization of transient problem with maximum dynamic response constraint using SOAR scheme

《机械工程前沿（英文）》 2021年第16卷第3期页码 593-606 doi: 10.1007/s11465-021-0636-4

摘要： This paper proposes a novel method for the continuum topology optimization of transient vibration problem with maximum dynamic response constraint. An aggregated index in the form of an integral function is presented to cope with the maximum response constraint in the time domain. The density filter solid isotropic material with penalization method combined with threshold projection is developed. The sensitivities of the proposed index with respect to design variables are conducted. To reduce computational cost, the second-order Arnoldi reduction (SOAR) scheme is employed in transient analysis. Influences of aggregate parameter, duration of loading period, interval time, and number of basis vectors in the SOAR scheme on the final designs are discussed through typical examples while unambiguous configuration can be achieved. Through comparison with the corresponding static response from the final designs, the optimized results clearly demonstrate that the transient effects cannot be ignored in structural topology optimization.

关键词： topology optimization solid isotropic material with penalization transient response aggregation function second-order Arnoldi reduction