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Heterosis for water uptake by maize (Zea mays L.) roots under water deficit: responses at cellular, single-root and whole-root system levels

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Journal of Arid Land 2013年第2期5卷 255-265页

作者： XiaoFang LIU SuiQi ZHANG lun shan State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Northwest A&F University Graduate University of Chinese Academy of Sciences

To examine the potential heterosis for water uptake by maize roots, the hydraulic properties of roots in the F1 hybrid （Hudan 4） were compared with those of its inbred parents （ 478 and Tian 4） at cellular, single-root and whole-root system levels under well-watered and water-deficit conditions. The cell hydraulic conductivity （Lpc） decreased under water deficit, but the Lpc of the F1 was higher than that of its inbred parents with or without stress from water deficit. Marked reductions in Lpc were observed following Hg2＋ treatment. The hydrostatic hydraulic conductivity of single roots （hydrostatic Lpsr） varied among genotypes under the two water treatments, with the highest in the F1 and the lowest in 478. Radial hydraulic conductivity （radial Lpsr） and axial hydraulic conductance （Lax） of the three genotypes varied similarly as Lpsr. The variations in hydraulic parameters were related to root anatomy. Radial Lpsr was negatively correlated with the ratio of cortex width to root diameter （R2=-0.77, P〈0.01）, whereas Lax was positively correlated with the diameter of the central xylem vessel （R2=0.75, P〈0.01） and the cross-sectional area of xylem vessels （R2=0.93, P〈0.01 ）. Hydraulic conductivity （Lpwr） and conductance （Lwr） of the whole-root system followed the same trend under the two water treatments, with the highest values in the F1. The results demonstrated that heterosis for water uptake by roots of the F1 occurred at cellular, single-root and whole-root system levels under well-watered and water-deficit conditions.

关键词： heterosis water uptake hydraulic conductivity water deficit maize

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Change of water use efficiency and its relation with root system growth in wheat evolution

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Chinese Science Bulletin 2002年第22期47卷 1879-1883页

作者： ZHANG Suiqi shan lun DENG Xiping Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesNorthwest Sci-Tech University of Agriculture and ForestryState Key Lab.of Soil Erosion and Dryland Farming on Loess PlateauYangling 712100China

Raising crop water use efficiency (WUE) is the physiological basis to implement crop high efficiently using water. The present soil column and field experiments are designed to investigate the change of wheat WUE (Triticum aestivum L.) at whole plant level and root system growth in evolution and the relationship between WUE and its root system growth using 10 wheat evolution genotypes with different ploidy chromosomes sets. Results show that in wheat evolution from 2n→6n, WUE at whole plant level increases with the increase of ploidy chromosomes, and root system growth (root weight, root length) and root/shoot ratio of wheat decrease with the increase of ploidy chromosomes under dry and irrigated conditions. WUE is negatively correlated with root weight and root/shoot ratio of wheat in evolution, significantly. Root system growth has an adverse redundancy for WUE in wheat evolution, and the root redundancy reduces with the increase of ploidy chromosomes, which result in the increase of wheat WUE at

关键词： winter wheat evolution root system growth water use efficiency.

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Two New Group 3 LEA Genes of Wheat and Their Functional Analysis in Yeast

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Journal of Integrative Plant Biology 2005年第11期47卷 1372-1381页

作者： Jia-Ning YU Jin-Song ZHANG lun shan Shou-Yi CHEN Department of Life Sciences Northwest Sci- Tech University of Agriculture and Forestry Yangling 712100 China Key Laboratory of Plant Biotechnology Institute of Genetics and Developmental Biology the Chinese Academy of Sciences Beijing 100101 China

The group 3 late embryogenesis abundant （LEA） proteins are thought to protect cells from stresses associated with dehydration during periods of water deficit. To investigate the functions of different members of the group 3 LEA genes, we isolated and characterized two new group 3 LEA genes, namely TaLEA2 and TaLEA3, from wheat （Triticum aestivum L.） and introduced TaLEA2 and TaLEA3 into Saccharmyces cerevisiae to examine the effect of these genes on yeast cell tolerance to osmotic, salt, and cold stresses. The TaLEA2 gene encoded a protein of 211 amino acids and possessed five repeats of 11-mer amino acid motifs. The TaLEA3 gene encoded a polypeptide of 211 amino acids with nine repeated units. Overexpression of TaLEA2 and TaLEA3 improved stress tolerance in transgenic yeast cells when cultured in medium containing sorbitol, salt and-20℃ freezing treatments respectively. However, the yeast transformants with TaLEA2 seemed to be more tolerant to hyperosmotic and freezing stress than transformants with TaLEA3. This implies that a close relationship exists between function and the number of repeats of the 11- mer amino acid motif in the group 3 LEA protein.

关键词： late embryogenesis abundant (LEA) protein Saccharmyces cerevisiae stress tolerance wheat.

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Fighting for the poverty:a case study for human migration in the context of sustainable dryland farming development in the Southern Ningxia Hilly Area

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Frontiers of Agricultural Science and Engineering 2014年第1期1卷 62-69页

作者： Yongqing MA Jie CHEN Shuqi DONG lun shan The State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China College of Agriculture Shanxi Agricultural UniversityTaigu 030801China

The Southern Ningxia Hilly Area is one of the most impoverished areas of Ningxia Hui Autonomous Region(a province)of China due to an economy that mainly relies on agriculture,which is affected by droughts in two out of every three *** programs have attempted to develop an increased and sustainable level of scientifically based agricultural production while restoring the ***,since the population exceeds the capacity of the land to adequately support it,a program is underway to move 350000 people to more suitable *** paper outlines the past improvements to the Southern Ningxia Hilly Area and considers future development in the context of migration for ecological reasons.

关键词： agricultural production animal husbandry development strategy ecological migration

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Advances in Biological Water-saving Research:Challenge and Perspectives

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Science Foundation in China 2006年第2期14卷 41-48页

作者： lun shan Xiping Deng Suiqi Zhang Institute of Soil and Water Consenvation CAS Yangling 712100 Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100

Increasing the efficiency of water use by crops continues to escalate as a topic of concem because drought is a restrictive environmental factor for crop productivity woridwide .Greater yield per unit rainfall is one of the most important challenges in water-saving agriculture Besides water-saving by irrigation engineering and conservation tillage, a good understanding of factors limiting and/or regulating yleld now provides us with an opportunity to identify and then precisely seiect for physiciogical and breeding traits that increase the efficiency of water use and drought tolerance under water-limited conditions, biological water-saving is one means of achieving this goal, A definition of bilogical water-saving measures is proposed which embraces improvements in water use efficiency （WUE） and drought tolerance, by genetic improvement and physiological regulation. The preponderance of bilogical water-saving measures is discussed and strategies identified for working within natural resource constraints. The technology and future perspectives of bilogical water saving could provide not only new water-saving techniques but also a scientific base for application of water-saving irrigation and conservation tillage.

关键词： biological water saving water-use efficiency drought tolerance physiological regulation water saving breeding

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RESEARCH & PRACTICE OF WATER-SAVING AGRICULTURE

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Bulletin of the Chinese Academy of Sciences 1998年第1期12卷 42-49页

作者： shan lun(Institute of Soil & Water Conservation, CAS)

China is one of the world’s major agricultural countries. About 80% of its annual water consumption is used for fanning undertakings. On the other hand, China is a country deficient in water resources and in particular, the water shortage is embarrassingly serious in the north. So the current development of water-saving agriculture (WSA) is a way of easing the strain between the supply and demand of water. This article expounds the WSA’s status in the development of the national economy, its research and implementation, and suggests an institutional system of WSA to be established in this country.

关键词： PRACTICE OF WATER-SAVING AGRICULTURE RESEARCH WSA

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科学应对农业干旱

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干旱地区农业研究 2011年第2期29卷 1-5页

作者：山仑西北农林科技大学中国科学院水利部水土保持研究所陕西杨凌712100

干旱是一个全球性问题。随着全球气候变暖和人类活动加剧,干旱有明显加重趋势。为应对我国面临的农业干旱需正确认识和把握几个关系问题。(1)南北区域之间的关系:从水资源合理利用与粮食均衡增产角度看,目前"北粮南调"的做法不尽合理,... 详细信息

干旱是一个全球性问题。随着全球气候变暖和人类活动加剧,干旱有明显加重趋势。为应对我国面临的农业干旱需正确认识和把握几个关系问题。(1)南北区域之间的关系:从水资源合理利用与粮食均衡增产角度看,目前"北粮南调"的做法不尽合理,应加强南方地区农田水利工程建设,并做出有利于增强南方粮食生产能力的政策调整;(2)高、中、低产田之间的关系:在继续争取高产再高产的同时,应将着力点放在提高中低产田的产出水平上;(3)粮食增产与发展畜牧之间的关系:建设稳定的人工草地,加快发展草地畜牧业,促进农业与牧业的紧密结合;(4)常规技术与高新技术之间的关系:现阶段提高我国旱区粮食生产的主流技术仍属常规技术,应加快高新技术应用的步伐,把当前需求和长远发展有效统一起来。目前,应对农业干旱的技术途径主要有:(1)在缺水灌区和干旱山区推行半旱地农业,逐步形成灌溉农业、旱地农业和半旱地农业并存的农业用水新格局;(2)利用种间抗旱性差异建立节水型农业结构;(3)确立抗非生物逆境和资源高效利用,即抗逆、广适应的作物育种目标,特别是抗旱与水资源高效利用的目标;(4)因地制宜,广泛推行可同时起到保水、保土、培肥、增产综合作用的保护性耕作技术;(5)将开辟农业新水源-非常规水源作为应对农业干旱的一条重要出路;(6)以丰补歉,在当前科技水平下遭受严重干旱年份大幅度减产不可避免,要将气候的多变性与作物的适应性有效统一起来,对产量的要求不以单一年度为标准,而着眼于一个周期年的平衡。

关键词：农业干旱均衡增产半旱地农业非常规水源以丰补歉

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我国旱地农业发展中的几个问题

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干旱地区农业研究 2023年第3期41卷 2-4页

作者：山仑中国科学院、水利部水土保持研究所西北农林科技大学陕西杨凌712100

介绍了我国旱地农业发展的历程、成就和经验,并重点就农业结构调整和农田持续增产的技术途径进行了论述,认为培育抗旱节水新品种和发展半旱地农业是农田稳定持续增产的突破口,而通过调整种植业结构以发展草地畜牧业则是半干旱地区实现... 详细信息

介绍了我国旱地农业发展的历程、成就和经验,并重点就农业结构调整和农田持续增产的技术途径进行了论述,认为培育抗旱节水新品种和发展半旱地农业是农田稳定持续增产的突破口,而通过调整种植业结构以发展草地畜牧业则是半干旱地区实现生态环境改善和生产力同步提升的关键。此论述以期对指导半干旱地区农业发展和生态环境改善产生积极意义。

关键词：旱地农业抗旱品种结构调整同步提升

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植物抗旱生理研究与发展半旱地农业

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干旱地区农业研究 2007年第1期25卷 1-5页

作者：山仑中国科学院水利部水土保持研究所西北农林科技大学陕西杨凌712100

论述了植物抗旱性与节水生理研究趋向,介绍了发展半旱地农业的背景、意义与目标。根据近期植物水分关系方面的研究与实践结果,讨论了半旱地农业的生理生态基础及发展前景。

关键词：植物抗旱性节水生理半旱地农业整体抗旱性水分利用效率补偿效应多变低水环境

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高强度镶嵌自润滑材料的设计及摩擦实验

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南京航空航天大学学报 2005年第2期37卷 236-239页

作者：单昆仑向定汉南京航空航天大学材料科学与技术学院南京210016

铜基镶嵌型自润滑轴承的承载压强大约为5 0 MPa,难以满足重型工程机械对自润滑轴承的要求。本项研究利用赫兹接触理论及摩擦的粘着理论,导出了摩擦因数随载荷变化的定量关系,提出了以轴承钢代替传统镶嵌型复合材料的铜合金的设计方案,... 详细信息

铜基镶嵌型自润滑轴承的承载压强大约为5 0 MPa,难以满足重型工程机械对自润滑轴承的要求。本项研究利用赫兹接触理论及摩擦的粘着理论,导出了摩擦因数随载荷变化的定量关系,提出了以轴承钢代替传统镶嵌型复合材料的铜合金的设计方案,研制出新型轴承钢/聚四氟乙烯镶嵌型复合材料。摩擦实验结果表明,这种新型复合材料的承载压强可达到90 MPa,摩擦因数低于0 .1 5 ,能够满足苛刻工况条件下工程机械对重载自润滑轴承的要求。

关键词：复合材料滑动轴承摩擦磨损镶嵌型自润滑材料聚四氟乙烯

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