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OsDA1 positively regulates grain width in rice
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作者 Cong Li Jun Liu +4 位作者 Liya Zhang Tao Li Hongyu Li Bin Liu Tao Zhao 《The Crop Journal》 SCIE CSCD 2024年第1期92-101,共10页
The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed i... The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed in young spikelets and glumes.Its overexpression led to enlarged seeds with increased width and decreased length/width ratio(LWR)and knocking out OsDA1 reduced grain width and increased grain length and LWR.A R310K point mutation in the DA1-like domain is a potential target for breeding for increased grain width and length.OsDA1 interacted with TCP gene-family proteins to regulate grain size and shape.Our findings deepen our understanding of the molecular mechanisms underlying grain size regulation and provide useful information for improving grain yield. 展开更多
关键词 RICE Osda1 grain size grain shape grain length/width ratio TCP
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Grain boundary engineering for enhancing intergranular damage resistance of ferritic/martensitic steel P92
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作者 Lei Peng Shang-Ming Chen +6 位作者 Jing-Yi Shi Yong-Jie Sun Yi-Fei Liu Yin-Zhong Shen Hong-Ya He Hui-Juan Wang Jie Tian 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期186-199,共14页
Ferritic/martensitic(F/M)steel is widely used as a structural material in thermal and nuclear power plants.However,it is susceptible to intergranular damage,which is a critical issue,under service conditions.In this s... Ferritic/martensitic(F/M)steel is widely used as a structural material in thermal and nuclear power plants.However,it is susceptible to intergranular damage,which is a critical issue,under service conditions.In this study,to improve the resistance to intergranular damage of F/M steel,a thermomechanical process(TMP)was employed to achieve a grain boundary engineering(GBE)microstructure in F/M steel P92.The TMP,including cold-rolling thickness reduction of 6%,9%,and 12%,followed by austenitization at 1323 K for 40 min and tempering at 1053 K for 45 min,was applied to the as-received(AR)P92 steel.The prior austenite grain(PAG)size,prior austenite grain boundary character distribution(GBCD),and connectivity of prior austenite grain boundaries(PAGBs)were investigated.Compared to the AR specimen,the PAG size did not change significantly.The fraction of coincident site lattice boundaries(CSLBs,3≤Σ≤29)and Σ3^(n) boundaries along PAGBs decreased with increasing reduction ratio because the recrystallization fraction increased with increasing reduction ratio.The PAGB connectivity of the 6%deformed specimen slightly deteriorated compared with that of the AR specimen.Moreover,potentiodynamic polarization studies revealed that the intergranular damage resistance of the studied steel could be improved by increasing the fraction of CSLBs along the PAGBs,indicating that the TMP,which involves low deformation,could enhance the intergranular damage resistance. 展开更多
关键词 grain boundary engineering Ferritic/martensitic steel Prior austenite grain boundary character distribution grain boundary connectivity Intergranular damage resistance
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qGW11a/OsCAT8,encoding an amino acid permease,negatively regulates grain size and weight in rice
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作者 Peng Gao Feifan Chen +16 位作者 Haitang Liu Shijun Fan Jierui Zeng Xue Diao Yang Liu Wencheng Song Shifu Wang Jing Li Xiaobo Zhu Bin Tu Weilan Chen Ting Li Yuping Wang Bingtian Ma Shigui Li Hua Yuan Peng Qin 《The Crop Journal》 SCIE CSCD 2024年第4期1150-1158,共9页
Grain size is a key factor influencing grain weight in rice.In this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to ... Grain size is a key factor influencing grain weight in rice.In this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to its donor parent 93-11.Further investigation identified two quantitative trait loci(QTL)on chromosome 11,designated qGW11a and qGW11b,which contribute to 1000-grain weight with an additive effect.LOC_Os11g05690,encoding the amino acid permease OsCAT8,is the target gene of qGW11a.Overexpression of OsCAT8 resulted in decreased grain weight,while OsCAT8 knockout mutants exhibited increased grain weight.The 287-bp located within the OsCAT8 promoter region of 93-11 negatively regulates its activity,which is subsequently correlated with an increase in grain size and weight.These results suggest that OsCAT8 functions as a negative regulator of grain size and grain weight in rice. 展开更多
关键词 RICE grain size grain weight QTL OsCAT8
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Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms
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作者 H.T.Jeong S.W.Lee W.J.Kim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期316-331,共16页
The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαph... The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 K.The microstructural refinement of this alloy was achieved by employing high-ratio differential speed rolling.The best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were obtained.During the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 K.Therefore,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and mechanisms.In the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation mechanism.It was concluded that solute drag creep is unlikely to occur.During the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain hardening.Deformation mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests. 展开更多
关键词 Magnesium-lithium alloy SUPERPLASTICITY Severe plastic deformation grain size grain growth
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Higher Grain-Filling Rate in Inferior Spikelets of Tolerant Rice Genotype Offset Grain Yield Loss under Post-Anthesis High Night Temperatures
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作者 Nitin SHARMA Bhupinder SINGH +6 位作者 Subbaiyan Gopala KRISHNAN Haritha BOLLINEDI Pranab Kumar MANDAL Milan Kumar LAL Prakash Kumar JHA P.V.Vara PRASAD Anjali ANAND 《Rice science》 SCIE CSCD 2024年第5期572-586,I0059-I0061,共18页
Increased nighttime respiratory losses decrease the amount of photoassimilates available for plant growth and yield. We hypothesized that the increased respiratory carbon loss under high night temperatures(HNT) could ... Increased nighttime respiratory losses decrease the amount of photoassimilates available for plant growth and yield. We hypothesized that the increased respiratory carbon loss under high night temperatures(HNT) could be compensated for by increased photosynthesis during the day following HNT exposure. Two rice genotypes, Vandana(HNT-sensitive) and Nagina 22(HNT-tolerant), were exposed to HNT(4 ℃ above the control) from flowering to physiological maturity. They were assessed for alterations in the carbon balance of the source(flag leaf) and its subsequent impact on grain filling dynamics and the quality of spatially differentiated sinks(superior and inferior spikelets). Both genotypes exhibited significantly higher night respiration rates. However, only Nagina 22 compensated for the high respiration rates with an increased photosynthetic rate, resulting in a steady production of total dry matter under HNT. Nagina 22 also recorded a higher grain-filling rate, particularly at 5 and 10 d after flowering, with 1.5- and 4.0-fold increases in the translocation of ^(14)C sugars to the superior and inferior spikelets, respectively. The ratio of photosynthetic rate to respiratory rate on a leaf area basis was negatively correlated with spikelet sterility, resulting in a higher filled spikelet number and grain weight per plant, particularly for inferior grains in Nagina 22. Grain quality parameters such as head rice recovery, high-density grains, and gelatinization temperature were maintained in Nagina 22. An increase in the rheological properties of rice flour starch in Nagina 22 under HNT indicated the stability of starch and its ability to reorganize during the cooling process of product formation. Thus, our study showed that sink adjustments between superior and inferior spikelets favored the growth of inferior spikelets, which helped to offset the reduction in grain weight under HNT in the tolerant genotype Nagina 22. 展开更多
关键词 high night temperature inferior grain pasting property radiolabeled sugar superior grain
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Grain-filling strategies of wheat of contrasting grain sizes under various planting patterns and irrigation levels
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作者 Zimeng Liang Jingyi Feng +4 位作者 Jiayu Li Yangyang Tang Tiankang He Vinay Nangia Yang Liu 《The Crop Journal》 SCIE CSCD 2024年第3期897-906,共10页
In a study comparing grain filling and yield in a large-and a small-grain-size wheat cultivar under two planting patterns and two irrigation regimes,plastic-covered ridge and furrow planting with sprinkler irrigation ... In a study comparing grain filling and yield in a large-and a small-grain-size wheat cultivar under two planting patterns and two irrigation regimes,plastic-covered ridge and furrow planting with sprinkler irrigation increased grain filling and yield in both cultivars.The largest contributors to grain yield were an extended active grain-filling period in Shuangda 1 and an increased mean grain-filling rate in XN538. 展开更多
关键词 Plastic-covered ridge and furrow cultivation Sprinkler irrigation WHEAT grain size grain filling
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Utilizing sediment grain size characteristics to assess the effectiveness of clay–sand barriers in reducing aeolian erosion in Minqin desert area,China
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作者 SONG Dacheng ZHAO Wenzhi +5 位作者 LI Guangyu WEI Lemin WANG Lide YANG Jingyi WU Hao MA Quanlin 《Journal of Arid Land》 SCIE CSCD 2024年第5期668-684,共17页
The clay–sand barriers in Minqin desert area,China,represent a pioneering windbreak and sand fixation project with a venerable history of 60 a.However,studies on evaluating the long-term effectiveness of clay–sand b... The clay–sand barriers in Minqin desert area,China,represent a pioneering windbreak and sand fixation project with a venerable history of 60 a.However,studies on evaluating the long-term effectiveness of clay–sand barriers against aeolian erosion,particularly from the perspective of surface sediment grain size,are limited and thus insufficient to ascertain the protective impact of these barriers on regional aeolian activities.This study focused on the surface sediments(topsoil of 0–3 cm depth)of clay–sand barriers in Minqin desert area to explain their erosion resistance from the perspective of surface sediment grain size.In March 2023,six clay–sand barrier sampling plots with clay–sand barriers of different deployment durations(1,5,10,20,40,and 60 a)were selected as experimental plots,and one control sampling plot was set in an adjacent mobile sandy area without sand barriers.Surface sediment samples were collected from the topsoil of each sampling plot in the study area in April 2023 and sediment grain size characteristics were analyzed.Results indicated a predominance of fine and medium sands in the surface sediments of the study area.The deployment of clay–sand barriers cultivated a fine quality in grain size composition of the regional surface sediments,increasing the average contents of very fine sand,silt,and clay by 30.82%,417.38%,and 381.52%,respectively.This trend became markedly pronounced a decade after the deployment of clay–sand barriers.The effectiveness of clay–sand barriers in erosion resistance was manifested through reduced wind velocity,the interception of sand flow,and the promotion of fine surface sediment particles.Coarser particles such as medium,coarse,and very coarse sands predominantly accumulated on the external side of the barriers,while finer particles such as fine and very fine sands concentrated in the upwind(northwest)region of the barriers.By contrast,the contents of finest particles such as silt and clay were higher in the downwind(southeast)region of the sampling plots.For the study area,the deployment of clay–sand barriers remains one of the most cost-effective engineering solutions for aeolian erosion control,with sediment grain size parameters serving as quantitative indicators for the assessment of these barriers in combating desertification.The results of this study provide a theoretical foundation for the construction of windbreak and sand fixation systems and the optimization of artificial sand control projects in arid desert areas. 展开更多
关键词 clay-sand barriers sediment grain size grain size distribution aeolian erosion windbreak and sand fixation Minqin desert area
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A novel Effective Panicle Number per Plant 4 haplotype enhances grain yield by coordinating panicle number and grain number in rice
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作者 Yun Wang Xiaoqian Wang +6 位作者 Laiyuan Zhai Sundus Zafar Congcong Shen Shuangbing Zhu Kai Chen Yun Wang Jianlong Xu 《The Crop Journal》 SCIE CSCD 2024年第1期202-212,共11页
Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-... Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-wide association analysis to identify the EPN4 gene,which is allelic to NARROW LEAF1(NAL1).Overexpression lines containing the Teqing allele(TQ)of EPN4 had significantly increased EPN.NIL-EPN4^(TQ) in japonica(geng)cultivar Lemont(LT)exhibited significantly improved EPN but decreased grain number and flag leaf size relative to LT.Haplotype analysis indicated that accessions with EPN4-1 had medium EPN,medium grain number,and medium grain weight,but had the highest grain yield among seven haplotypes,indicating that EPN4-1 is an elite haplotype of EPN4 for positive coordination of the three components of grain yield.Furthermore,accessions carrying the combination of EPN4-1 and haplotype GNP1-6 of GNP1 for grain number per panicle showed higher grain yield than those with other allele combinations.Therefore,pyramiding of EPN4-1 and GNP1-6 could be a preferred approach to obtain high yield potential in breeding. 展开更多
关键词 RICE Effective panicle number per plant grain number per panicle HAPLOTYPE grain yield potential
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Rice AGL1 determines grain size and sterile lemma identity
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作者 Haiping Yu An Wang +4 位作者 Guangheng Zhang Guojun Dong Longbiao Guo Qian Qian Deyong Ren 《The Crop Journal》 SCIE CSCD 2024年第2期630-634,共5页
The grass spikelet is a unique inflorescence structure that determines grain size.Although many genetic factors have been well characterized for grain size and glume development,the underlying molecular mechanisms in ... The grass spikelet is a unique inflorescence structure that determines grain size.Although many genetic factors have been well characterized for grain size and glume development,the underlying molecular mechanisms in rice are far from established.Here,we isolated rice gene,AGL1 that controlled grain size and determines the fate of the sterile lemma.Loss of function of AGL1 produced larger grains and reduced the size of the sterile lemma.Larger grains in the agl1 mutant were caused by a larger number of cells that were longer and wider than in the wild type.The sterile lemma in the mutant spikelet was converted to a rudimentary glume-like organ.Our findings showed that the AGL1(also named LAX1)protein positively regulated G1 expression,and negatively regulated NSG1 expression,thereby affecting the fate of the sterile lemma.Taken together,our results revealed that AGL1 played a key role in negative regulation of grain size by controlling cell proliferation and expansion,and supported the opinion that rudimentary glume and sterile lemma in rice are homologous organs. 展开更多
关键词 Abnormal grain and sterile lemma 1 Oryza sativa grain size Rudimentary glume
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Research on Heredity of Coarse Ferrite Grains
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作者 Wangzhan FAN Weimin GUI Youfeng CHEN 《Research and Application of Materials Science》 2024年第1期5-8,共4页
The changes in austenite grain size of the specimens with coarse ferrite grains under different heat treatment process were investigated.The focus was on studying the effect of annealing on refining coarse ferrite gra... The changes in austenite grain size of the specimens with coarse ferrite grains under different heat treatment process were investigated.The focus was on studying the effect of annealing on refining coarse ferrite grains,as well as the influence of the ferrite grain size on the main technical indicators of gas carburizing.The results show that coarse ferrite grains may not necessarily cause the coarse austenite grains,but may result in mixed austenite grains.After annealing treatment,the coarse ferrite grains can be significantly refined and homogenized.Moreover,the coarse ferrite grains have no significant effects on hardnessand intergranular oxidationof gas carburizing. 展开更多
关键词 grain size coarse ferrite grains AUSTENITE gas carburizing
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Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions 被引量:2
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作者 Jingui Wei Qiang Chai +5 位作者 Wen Yin Hong Fan Yao Guo Falong Hu Zhilong Fan QimingWang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期122-140,共19页
The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.H... The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas. 展开更多
关键词 water and N reduction plant density MAIZE grain yield N uptake compensation effect
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基于Grain v1的认证加密算法研究与设计
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作者 林紫欣 鲁小娟 张艳硕 《北京电子科技学院学报》 2024年第1期23-39,共17页
Grain v1算法为eSTREAM项目面向硬件的优胜算法之一,在硬件实现方面极具优势。本文针对Grain v1的结构弱点对其进行细节修改,并在此基础上提出Grain v1+AE和Grain v1+AEAD两种认证加密算法。这两种算法在保证机密性和完整性的同时,为Gr... Grain v1算法为eSTREAM项目面向硬件的优胜算法之一,在硬件实现方面极具优势。本文针对Grain v1的结构弱点对其进行细节修改,并在此基础上提出Grain v1+AE和Grain v1+AEAD两种认证加密算法。这两种算法在保证机密性和完整性的同时,为Grain系列认证加密算法在安全等级、硬件规模角度提供更多选择,拓展Grain系列算法适用范围。 展开更多
关键词 grain v1 认证加密算法 AEAD 密码分析 安全性 面向硬件设计
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Auxin-brassinosteroid crosstalk:Regulating rice plant architecture and grain shape
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作者 Meidi Wu Jing Zhou +3 位作者 Qian Li Dunfan Quan Qingwen Wang Yong Gao 《The Crop Journal》 SCIE CSCD 2024年第4期953-963,共11页
Rice(Oryza sativa)plant architecture and grain shape,which determine grain quality and yield,are modulatedby auxin and brassinosteroid via regulation of cell elongation and proliferation.We review the signaltransducti... Rice(Oryza sativa)plant architecture and grain shape,which determine grain quality and yield,are modulatedby auxin and brassinosteroid via regulation of cell elongation and proliferation.We review the signaltransduction of these hormones and the crosstalk between their signals on the regulation of rice plantarchitecture and grain shape. 展开更多
关键词 AUXIN BRASSINOSTEROID Auxin-brassinosteroid crosstalk Plant architecture grain shape
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Genes controlling grain chalkiness in rice
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作者 Luo Chen Xiumei Li +6 位作者 Minhua Zheng Rui Hu Jingfang Dong Lingyan Zhou Wuge Liu Dilin Liu Wu Yang 《The Crop Journal》 SCIE CSCD 2024年第4期979-991,共13页
With rising living standards,there is an increasing demand for high-quality rice.Rice quality is mainly defined by milling quality,appearance quality,cooking and eating quality,and nutrition quality.Among them,chalkin... With rising living standards,there is an increasing demand for high-quality rice.Rice quality is mainly defined by milling quality,appearance quality,cooking and eating quality,and nutrition quality.Among them,chalkiness is a key trait for appearance quality,which adversely affects cooking and eating quality,head rice yield,and commercial value.Therefore,chalkiness is undesirable,and reducing chalkiness is a major goal in rice quality improvement.However,chalkiness is a complex trait jointly influenced by genetic and environmental factors,making its genetic study and precision improvement a huge challenge.With the rapid development of molecular techniques,much knowledge has been gained about the genes and molecular networks involved in chalkiness formation.The present review describes the major environmental factors affecting chalkiness and summarizes the quantitative trait loci(QTL)associated with chalkiness.More than 150 genes related to chalkiness formation have been reported.The functions of the genes regulating chalkiness,primarily those involved in starch synthesis,storage protein synthesis,transcription regulation,organelle development,grain shape regulation,and hightemperature response,are described.Finally,we identify the challenges associated with genetic improvement of chalkiness and suggest potential strategies.Thus,the review offers insight into the molecular dynamics of chalkiness and provides a strong basis for the future breeding of high-quality rice varieties. 展开更多
关键词 RICE grain quality CHALKINESS QTL identification Gene
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Grain size and surface micro-texture characteristics and their paleoenvironmental significance of Holocene sediment in southern margin of the Gurbantunggut Desert,China
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作者 MA Yunqiang LI Zhizhong +2 位作者 TAN Dianjia ZOU Xiaojun TAO Tonglian 《Journal of Arid Land》 SCIE CSCD 2024年第5期632-653,共22页
The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant imp... The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant importance for understanding the interactive processes of wind and water forces,as well as the provenance of sediment.However,there are relatively few investigations on the characteristics of such sediment at present.In this study,we researched three aeolian-alluvial interactive stratigraphic profiles and different types of surface sediment on the desert-oasis transitional zone of southern margin of the Gurbantunggut Desert.Based on the optically stimulated luminescence(OSL)dating of aeolian sand and analyses of quartz sand grain size and surface micro-texture,we explored the aeolian-alluvial environmental change at southern margin of the desert in Holocene,as well as the provenance of sediment.The results indicated that the grain size characteristics of different types of sediment in the stratigraphic profiles were similar to those of modern dune sand,interdune sand,muddy desert surface soil,and riverbed sand.Their frequency curves were unimodal or bimodal,and cumulative probability curves were two-segment or three-segment,mainly composed of suspension load and saltation load.The quartz sand in the sediment at southern margin of the desert had undergone alternating transformation of various exogenic forces,with short transportation distance and time,and sedimentary environment was relatively humid.In Holocene,southern margin of the desert primarily featured braided river deposits,and during intermittent period of river activity,there were also aeolian deposits such as sand sheet deposits,stabilized dune deposits,and mobile dune deposits.The provenance for Holocene alluvial deposits at southern margin of the desert remains relatively constant,with the debris of the Tianshan Mountains being the primary provenance.Aeolian sand is mainly near-source recharge,which is formed by in situ deposition of fluvial or lacustrine materials in southern margin of the desert transported by wind erosion,and its provenance was still the weathered debris of the Tianshan Mountains.In addition,the sand in interior of the desert may be transported by northwest wind in desert-scale,thus affecting the development of dunes in southern margin of the desert.The results of this study provide a reference for understanding the composition and provenance changes of desert sand in the context of global climate change. 展开更多
关键词 aeolian-alluvial deposition grain size surface micro-texture sedimentary environment HOLOCENE
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Quantitative analysis of laser-generated ultrasonic wave characteristics and their correlation with grain size in polycrystalline materials
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作者 徐兆文 白雪 +2 位作者 马健 万壮壮 王超群 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期526-543,共18页
Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was evaluated.The high energy of the pulsed laser with a la... Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was evaluated.The high energy of the pulsed laser with a large irradiation spot simultaneously generated ultrasonic longitudinal and shear waves at the epicenter under the slight ablation regime.An optimized denoising technique based on wavelet thresholding and variational mode decomposition was applied to reduce noise in shear waves with a low signal-to-noise ratio.An approach for characterizing grain size was proposed using spectral central frequency ratio(SCFR)based on time-frequency analysis.The results demonstrate that the generation regime of ultrasonic waves is not solely determined by the laser power density;even at high power densities,a high energy with a large spot can generate an ultrasonic waveform dominated by the thermoelastic effect.This is ascribed to the intensification of the thermoelastic effect with the proportional increase in laser irradiation spot area for a given laser power density.Furthermore,both longitudinal and shear wave SCFRs are linearly related to grain size in polycrystalline materials;however,the shear wave SCFR is more sensitive to finer-grained materials.This study holds great significance for evaluating metal material properties using laser ultrasound. 展开更多
关键词 laser-ultrasonics polycrystalline materials ultrasonic time-frequency characteristics grain size
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Correlation Study on Grain Size Characteristics and Geotechnical Properties of Surface Sediments in Qingdao Offshore Area
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作者 LI Anlong WANG Panpan +5 位作者 GUO Xijun JI Xiangkun SHEN Kunming LIN Lin YAN Zhichao YUAN Lin 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期721-730,共10页
The comprehension of sediment grain size parameters and the corresponding sedimentary environment holds paramount importance in elucidating the engineering geological attributes of the subaqueous seabed.This study del... The comprehension of sediment grain size parameters and the corresponding sedimentary environment holds paramount importance in elucidating the engineering geological attributes of the subaqueous seabed.This study delineated the sedimentary environment zoning in the northern sea area of Qingdao through cluster analysis of grain size parameters derived from 123 surface sediment samples.The study analyzed the correlation between sediment geotechnical indices and grain size parameters across diverse sedimentary environments.A correlation equation was established for samples exhibiting a strong correlation.The study found four distinct sedimentary environments in the study area:coastal,transitional,shallow sea,and residual.Within the same sedimentary environment,the average grain size and sorting coefficient exhibit significant correlations with geotechnical indices such as water content,density,shear strength,plastic limit,liquid limit,and plastic index.However,notable disparities in the correlation between grain size parameters and geotechnical indices emerge across different sedimentary environments. 展开更多
关键词 grain size parameters cluster analysis sedimentary environment CORRELATIONS geotechnical indexes
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Rice Grains from Slightly Saline Field Exhibited Unchanged Starch Physicochemical Properties but Enhanced Nutritional Values
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作者 Supranee SANTANOO Wichian SANGWONGCHAI +4 位作者 Maysaya THITISAKSAKUL Suphatta PHOTHISET Paweena PONGDONTRI Noppawan NOUNJAN Piyada THEERAKULPISUT 《Rice science》 SCIE CSCD 2024年第3期343-360,I0055-I0057,共21页
This study aims to investigate grain quality and nutritional values of rice(Pokkali,a salt-tolerant cultivar;RD73,a new cultivar improved from KDML105 introgressed with Saltol QTL from Pokkali,and KDML105,a moderately... This study aims to investigate grain quality and nutritional values of rice(Pokkali,a salt-tolerant cultivar;RD73,a new cultivar improved from KDML105 introgressed with Saltol QTL from Pokkali,and KDML105,a moderately salt-susceptible cultivar)grown under non-saline(0.04–0.87 dS/m)and slightly saline(1.08–4.83 dS/m)field conditions.The results revealed that salinity caused significant reduction in grain size but significant increments in reducing sugar and total protein contents in the grains.Nevertheless,the amounts of starch in the grains of KDML105 and Pokkali rice genotypes were unaffected by the stress.The starch granule size distribution was also unaffected by salinity.Interestingly,only starch from Pokkali was significantly diminished in amylose content,from 19.18%to 16.99%.Accordingly,parameters relating to starch gelatinization,retrogradation,and pasting properties of KDML105 and RD73 were unaffected by salinity;only Pokkali showed a significant increase in percentage of retrogradation along with a significant reduction in gelatinization enthalpy.In the saline field,total phenolic content and antioxidant capacity in the grains of all rice cultivars tended to increase,particularly in Pokkali.On average,essential element contents in grains from the saline-treated plants showed a 33%,32%,32%,22%,20%,11%,and 10%increase in total P,N,K,Mg,Zn,Fe,and Ca content,respectively.Interestingly,total Fe content exhibited the greatest percentage of increments in KDML105(187%).Taken together,cultivation of rice in the slightly saline field did not alter its eating and cooking qualities,while enhanced some nutritional properties such as proteins,minerals,and secondary metabolites like phenolic compounds. 展开更多
关键词 antioxidant capacity elemental composition GELATINIZATION grain morphology RETROGRADATION rice salt stress starch granule
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Natural variation of an autophagy-family gene among rice subspecies affects grain size and weight
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作者 Shiying Huang Peng Wang +10 位作者 Caijing Li Qingwen Zhou Tao Huang Yicong Cai Qin Cheng Hui Wang Qi Zhong Zhihao Chen Liping Chen Haohua He Jianmin Bian 《The Crop Journal》 SCIE CSCD 2024年第1期121-132,共12页
Elucidating the genetic basis of natural variation in grain size and weight among rice varieties can help breeders develop high-yielding varieties.We identified a novel gene,GW3a(Grain Weight 3a)(LOC_Os03g27350),that ... Elucidating the genetic basis of natural variation in grain size and weight among rice varieties can help breeders develop high-yielding varieties.We identified a novel gene,GW3a(Grain Weight 3a)(LOC_Os03g27350),that affects rice grain size and weight.gw3a mutants showed higher total starch content and dry matter accumulation than the wild type(WT),Nipponbare,suggesting that GW3a negatively regulates grain size and weight.Moreover,our study found that GW3a interacted with OsATG8 by cleaving it,suggesting that GW3a may be involved in the assembly of autophagosomes and starch degradation in plants.The haplotype analysis of GW3a showed functional differences between indica and japonica rice.Taken together,we conclude that GW3a is expressed in the autophagosome pathway regulating starch metabolism in rice,affecting yield-related traits,such as grain size,grain weight and thousand grain weight(TGW).Our findings also shed new light on autophagy-mediated yield trait regulation,proposing a possible strategy for the genetic improvement of high-yield germplasm in rice. 展开更多
关键词 grain size GW3a AUTOPHAGY Starch content
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Genetic analysis and fine mapping of a grain size QTL in the smallgrain sterile rice line Zhuo201S
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作者 Bin Lei Jiale Shao +5 位作者 Feng Zhang Jian Wang Yunhua Xiao Zhijun Cheng Wenbang Tang Jianmin Wan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2155-2163,共9页
The development and application of the small-grain rice sterile line Zhuo201S(Z201S)has demonstrated its potential for mechanized hybrid rice seed production,leading to significant cost reductions.However,the molecula... The development and application of the small-grain rice sterile line Zhuo201S(Z201S)has demonstrated its potential for mechanized hybrid rice seed production,leading to significant cost reductions.However,the molecular mechanism responsible for the small-grain size characteristic of Z201S remains unclear.In this study,we conducted a genetic analysis using near-isogenic lines constructed from Z210S,a small-grain rice sterile line,and R2115,a normal-grain variety.The results revealed that the small-grain trait in Z201S is governed by a single partially dominant gene which also enhances grain number.Through mapping,we localized the causal gene to the short arm of chromosome 2,within a 113 kb physical region delimited by the molecular markers S2-4-1 and LB63.Transgenic analysis and gene expression assays indicated LOC_Os02g14760 as the most likely candidate gene,suggesting that the small-grain size trait of Z201S is controlled by a novel locus that has not been previously identified. 展开更多
关键词 RICE grain size map-based cloning
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