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Yield potential and stability in super hybrid rice and its production strategies

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Journal of Integrative Agriculture 2017年第5期16卷 1009-1017页

作者： HUANG Min tang qi-yuan AO He-jun ZOU Ying-bin Southern Regional Collaborative Innovation Center for Grain and Oil Crops(CICGO) Hunan Agricultural UniversityChangsha 410128P.R.China

China＇s Super Hybrid Rice Breeding Program has made significant progress over the past two decades. In this paper, we reviewed our studies on the yield potential and stability in super hybrid rice and discussed the strategies for super hybrid rice production. The results of our studies show that rice yield potential has been increased by 12% in super hybrid cultivars as compared with ordinary hybrid and inbred cultivars. The higher grain yields in super hybrid rice cultivars are attributed to larger panicle size coupled with higher biomass production or higher harvest index. However, grain yields in super hybrid rice cultivars vary widely among locations depending on soil and climatic factors. Therefore, it is important to tailor target yield to local conditions in super hybrid rice production. The target yield for super hybrid rice production can be determined by the average yield method or the regression model method. Improving soil quality is critical to achieving the target yield in super hybrid rice production. Favorable crop rotations such as rice-oilseed rape and novel soil management practices, such as biochar addition, are effective approaches to improve soil quality. It is needed to develop simplified cultivation tech- nologies for super hybrid rice to meet the changes in socioeconomic environments during the period of transition. There are such technologies as no-tillage direct seeding and mechanized transplanting at high hill density with single seedling per hill.

关键词： mechanized transplanting no-tillage direct seeding super hybrid rice target yield yield potential yield stability

基于MaxEnt模型预测贵州香禾糯的潜在适生区分布

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中国农业气象 2024年第8期45卷 872-881页

作者：杨凡杨胜海郑华斌王慰亲唐启源湖南农业大学农学院长沙410128 黔东南州农业技术推广站凯里522600

基于实地记录和文献资料的贵州香禾糯实际分布数据,采用Kuenm包优化的最大熵模型(MaxEnt),研究历史和未来气候情景下贵州香禾糯适生区以及影响香禾糯分布的主导气候因子,为气候变化背景下合理规划香禾糯生产布局提供参考依据。结果表明:... 详细信息

基于实地记录和文献资料的贵州香禾糯实际分布数据,采用Kuenm包优化的最大熵模型(MaxEnt),研究历史和未来气候情景下贵州香禾糯适生区以及影响香禾糯分布的主导气候因子,为气候变化背景下合理规划香禾糯生产布局提供参考依据。结果表明:(1)1970−2000年历史时期,香禾糯潜适生区主要集中在贵州省黔东南州的东南部,高适生区分布在从江、榕江、黎平三县。(2)相比于历史时期,SSP126气候情景下香禾糯高适生区在2041−2060年面积增加并向高海拔处推移,2081−2100年面积减小并向高纬度推移。SSP245气候情景下香禾糯高适生区在2041−2060年面积增加并向高纬度推移,2081−2100年面积减小并向高海拔处推移。SSP585气候情景下香禾糯高适生区在2041−2060年面积增加并向高海拔处推移,2081−2100年面积减小并向高海拔处推移。(3)在19个气候影响因子中,最冷月份最低温度、平均昼夜温差是影响香禾糯分布的主要气候因子,其影响分布的贡献率分别为34.8%和13.8%。总体而言,气候变化将导致香禾糯高适生区面积在2041−2060年扩大,在2081−2100年缩小,因此需重视气候变化,合理规划香禾糯生产布局,保障粮食安全性。

关键词：香禾糯气候变化 MaxEnt模型潜在适生区模型优化

Comparisons of Yield and Growth Behaviors of Hybrid Rice Under Different Nitrogen Management Methods in Tropical and Subtropical Environments

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Journal of Integrative Agriculture 2013年第4期12卷 621-629页

作者： Ibrahim Md PENG Shao-bing tang qi-yuan HUANG Min JIANG Peng ZOU Ying-bin College of Agronomy Hunan Agricultural University Crop Physiology and Production Center (CPPC) Huazhong Agricultural University

To compare the grain yield and growth behaviors of hybrid rice, field experiments were conducted in a subtropical environment in Changsha, Hunan Province, China, and in two tropical environments in Gazipur and Habiganj in Bangladesh during 2009 to 2011. Three hybrid rice cultivars were grown under three nitrogen （N） management treatments in each experiment. The results showed that grain yield was significantly affected by locations, N treatments and their interaction but not by cultivars. Changsha produced 8-58% higher grain yields than Bangladesh locations. Sink size （spikelet number per unit land area） was responsible for these yield differences. Larger panicle size （spikelet number per panicle） contributed to greater sink size in Changsha. Aboveground total biomass was greater in Changsha than in Bangladesh locations, whereas harvest index was higher in Bangladesh locations than in Changsha. Crop growth rate （CGR） was greater at Changsha than Bangladesh locations during vegetative phase, while the difference was relatively small and not consistent during the later growth phases. Higher leaf area index and leaf area duration were partly responsible for the greater CGR in Changsha. Real-time N management （RTNM） produced lower grain yields than fixed-time N management in more than half of the experiments. Our study suggested that further improvement in rice yield in the tropical environments similar to those of Bangladesh will depend mainly on the ability to increase panicle size as well as CGR during vegetative phase, and the chlorophyll meter threshold value used in RTNM needs to be modified according to environmental conditions and cultivar characteristics to achieve a desirable grain yield.

关键词： crop growth rate biomass production hybrid rice leaf area duration leaf area index real-time nitrogenmanagement

Development of component stiffness equations for thread-fixed one-side bolt connections to an enclosed rectangular hollow section column under tension

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： Fu-Wei WU yuan-qi LI Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation

Effect of Nitrogen Regimes on Grain Yield,Nitrogen Utilization,Radiation Use Efficiency,and Sheath Blight Disease Intensity in Super Hybrid Rice

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Journal of Integrative Agriculture 2012年第1期11卷 134-143页

作者： LI Di-qin tang qi-yuan ZHANG Yun-bo qiN Jian-quan LI Hu CHEN Li-jun YANG Sheng-hai ZOU Ying-bin PENG Shao-bing State Key Laboratory of Hybrid Rice Hunan Agricultural University Changsha Hunan 410128 P.R.China Crop Physiology and Production Center （CPPC） Huazhong Agricultural University Wuhan 430070 P..R.China

Poor nitrogen use efficiency in rice production is a critical issue in China. Site-specific N managements （SSNM） such as real-time N management （RTNM） and fixed-time adjustable-dose N management （FTNM） improve fertilizer-N use efficiency of irrigated rice. This study was aimed to compare the different nitrogen （N） rates and application methods （FFP, SSNM, and RTNM methods） under with- and without-fungicide application conditions on grain yield, yield components, solar radiation use efficiency （RUE）, agronomic-nitrogen use efficiency （AEN）, and sheath blight disease intensity. Field experiments were carried out at Liuyang County, Hunan Province, China, during 2006 and 2007. A super hybrid rice Liangyou 293 （LY293） was used as experimental material. The results showed that RTNM and SSNM have great potential for improving agronomic-nitrogen use efficiency without sacrificing the grain yield. There were significant differences in light interception rate, sheath blight disease incidence （DI） and the disease index （ShBI）, and total dry matter among the different nitrogen management methods. The radiation use efficiency was increased in a certain level of applied N. But, the harvest index （HI） decreased with the increase in applied N. There is a quadratic curve relationship between grain yield and applied N rates. With the same N fertilizer rate, different fertilizer-N application methods affected the RUE and grain yield. The fungicide application not only improved the canopy light interception rate, RUE, grain filling, and harvest index, but also reduced the degree of sheath blight disease. The treatment of RTNM under the SPAD threshold value 40 obtained the highest yield. While the treatment of SSNM led to the highest nitrogen agronomic efficiency and higher rice yield, and decreased the infestation of sheath blight disease dramatically as well. Nitrogen application regimes and diseases control in rice caused obvious effects on light interception rate, RUE, and HI. Optim

关键词： super hybrid rice real-time N management fixed-time adjustable-does N management grain yield sheath blight radiation use efficiency agronomic-nitrogen use efficiency

Dynamic Scene Graph Generation of Point Clouds with Structural Representation Learning

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Tsinghua Science and Technology 2024年第1期29卷 232-243页

作者： Chao qi Jianqin Yin Zhicheng Zhang Jin tang School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China Standard and Metrology Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

Scene graphs of point clouds help to understand object-level relationships in the 3D *** graph generation methods work on 2D structured data,which cannot be used for the 3D unstructured point cloud *** point-cloud-based methods generate the scene graph with an additional graph structure that needs labor-intensive manual *** address these problems,we explore a method to convert the point clouds into structured data and generate graphs without given ***,we cluster points with similar augmented features into groups and establish their relationships,resulting in an initial structural representation of the point ***,we propose a Dynamic Graph Generation Network(DGGN)to judge the semantic labels of targets of different *** dynamically splits and merges point groups,resulting in a scene graph with high *** show that our methods outperform other baseline *** output reliable graphs describing the object-level relationships without additional manual labeled data.

关键词： scene graph generation structural representation point cloud

Microglial Calcium Homeostasis Modulator 2:Novel Anti-neuroinflammation Target for the Treatment of Neurodegenerative Diseases

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Neuroscience Bulletin 2024年第4期40卷 553-556页

作者： yuan Dong Li tang Neuropsychiatry Research Institute The Affiliated Hospital of Qingdao UniversityQingdao UniversityQingdao266000China qingdao Institute of Measurement Technology Qingdao266000China

Neurodegenerative diseases,including Alzheimer's disease(AD)and Parkinson's disease(PD),are the most common causes of *** drugs for such diseases can only provide temporary help with the symptoms,leaving the discovery of new drugs urgently in *** cells are the local immune cells in the nervous system and have been recognized as the key player in neuroinflammation that contributes to the process of neurodegeneration[1],raising the discussion of aiming microglia as the therapeutic target for clinical treatment of neurodegenerative diseases.

关键词： inflammation degenerative drugs

Screening of low-friction two-dimensional materials from highthroughput calculations using lubricating figure of merit

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Friction 2024年第8期12卷 1897-1908页

作者： Kewei tang Weihong qi Guoliang RU Weimin LIU State Key Laboratory of Solidification Processing and Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical UniversityXi’an 710072China Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing Yantai 265503China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Two-dimensional materials are excellent lubricants with inherent ***,superlubricity has been reported for only a few of these ***,other promising two-dimentional(2D)materials with different physical properties cannot be discovered or applied in production;thus,energy consumption can be greatly ***,we carry out high-throughput calculations for 1,4752D materials and screen for low-friction *** set a standard,we propose,for the first time,a geometry-independent lubricating figure of merit based on the conditions for stick-slip transition and our theory of Moiré*** the efficient calculation of this figure of merit,an innovative approach was developed based on an improved registry index *** calculations,340 materials were found to have a figure of merit lower than 10−***,a small set of 21 materials with a figure of merit lower than 10−4 were screened *** materials can provide diverse choices for various *** addition,the efficient computational approach demonstrated in this work can be used to study other stacking-dependent properties.

关键词： two-dimensional materials high-throughput calculation tribology low-friction materials Moirépatterns

Constructions of optimal binary locally repairable codes via intersection subspaces

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Science China(Information Sciences) 2024年第6期67卷 418-432页

作者： Wenqin ZHANG Deng tang Chenhao YING yuan LUO School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

Locally repairable codes（LRCs）, which can recover any symbol of a codeword by reading only a small number of other symbols, have been widely used in real-world distributed storage systems, such as Microsoft Azure Storage and Ceph Storage Cluster. Since binary linear LRCs can significantly reduce coding and decoding complexity, constructions of binary LRCs are of particular interest. The aim of this paper is to construct dimensional optimal binary LRCs with disjoint local repair groups. We introduce a method to connect intersection subspaces with binary LRCs and construct dimensional optimal binary linear LRCs with locality 2b（b 3） and minimum distance d 6 by employing intersection subspaces deduced from the direct sum. This method will sufficiently increase the number of possible repair groups of dimensional optimal LRCs, thus efficiently expanding the range of the construction parameters while keeping the largest code rates compared with all known binary linear LRCs with minimum distance d 6 and locality 2b.

关键词： locally repairable codes disjoint local repair groups distributed storage systems intersection subspaces direct sum