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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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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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Understanding of Five Grains for YANG:a way to straighten Asians’dietary structure
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作者 Jing-Chao Ma Cai-Jie Zhang +1 位作者 Wen-Li Zhao Ye Zhao* 《Food and Health》 2024年第3期18-19,共2页
According to the general opinion,grains should occupy the largest amount of human food each day,but this grain-based eating habit does not allow human life to be extended.Grains are high in carbohydrates and five comm... According to the general opinion,grains should occupy the largest amount of human food each day,but this grain-based eating habit does not allow human life to be extended.Grains are high in carbohydrates and five commonly recognized plant hormones,namely auxin,gibberellin,cytokinin,abscisic acid,and ethylene.Through in-depth analysis of ancient books,it was found that five grains for support:support is a restriction,and it means the essence,which means that grains should be eaten less,and it is the essence of the least daily intake.To correctly understand the Chinese dietary concept of"five grains for support"is the basis for improving Asian dietary health and promoting Asian human health. 展开更多
关键词 grains HORMONES Carbohydrates Eating habits
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Construction of Vectors to Express Foreign Protein within Potato Starch Grains 被引量:11
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作者 李珺 马力通 姚新灵 《Agricultural Science & Technology》 CAS 2009年第4期72-74,共3页
[Objective] The aim is to study the construction of vectors expressing foreign protein in potato starch grains specifically, and provide some reference for solving industrialized core problem of high cost and low expr... [Objective] The aim is to study the construction of vectors expressing foreign protein in potato starch grains specifically, and provide some reference for solving industrialized core problem of high cost and low expression level of foreign protein. [Method] By using molecular biological techniques of RT-PCR and nested PCR, plant expression vector for the foreign protein locating in the potato starch grains was constructed. [ Result] Coding sequence ( GC20 ) of potato starch grains that was located and expressed by GBSSI promoter was cloned. Plant expression vector was screened out through connection, transformation and enzyme digestion identification. [ Conclusion] This result laid a foundation for further screening the foreign protein on the potato starch grains. 展开更多
关键词 Foreign protein Plant bioreactor GBSSI GC20 Starch grains
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Phase-field simulation of forced flow effect on random preferred growth direction of multiple grains 被引量:1
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作者 王军伟 朱昌盛 +2 位作者 王智平 冯力 肖荣振 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1620-1626,共7页
The random distribution problem of dendrite preferred growth direction was settled by random grid method.This method was used to study the influence of forced laminar flow effect on multiple grains during solidificati... The random distribution problem of dendrite preferred growth direction was settled by random grid method.This method was used to study the influence of forced laminar flow effect on multiple grains during solidification.Taking high pure succinonitrile (SCN) undercooled melt as an example,the forced laminar flow effect on multiple grains was studied by phase-field model of single grain which coupled with flow equations at non-isothermal condition.The simulation results show that the random grid method can reasonably settle the problem of random distribution and is more effective.When the solid fraction is relatively low,melt particles flow around the downstream side of dendrite,and the flow velocity between two dendrite arms becomes high.At the stage of solidification time less than 1800Δt,every dendrite grows freely;the upstream dendrites are stronger than the downstream ones.The higher the melt flow rate,the higher the solid fraction.However,when the solid fraction is relatively high,the dendrite arm intertwins and only a little residual melt which is not encapsulated can flow;the solid fraction will gradually tend to equal to solid fraction of melt without flow. 展开更多
关键词 phase-field method multiple grains laminar flow preferred growth direction computer simulation SOLIDIFICATION flow velocity
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Research on Pollen Grains of Tetraploid Lines and Diploid Control Line of Chrysanthemum cinerariifolium (Trev.) Vis. 被引量:1
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作者 刘蓁 高山林 《Agricultural Science & Technology》 CAS 2010年第5期151-154,共4页
[Objective] The aim was to study characters of pollen grains of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium (Trev.) Vis.,morphological characters,fertility of pollen grain and germinatio... [Objective] The aim was to study characters of pollen grains of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium (Trev.) Vis.,morphological characters,fertility of pollen grain and germination percentage of seeds. [Method] Pollen grains were prepared by sulphuric acid-acetyl oxide decomposition method. The lengths of polar axis and equatorial axis of pollen grains were determined with general optical microscope. The morphology of pollen grains was observed with SEM (scanning electron microscope) and the typical visual fields of 2 500× (or 2 000×),7 000× were taken pictures. [Result] Comparing with the diploid control line,the pollen grains of five tetraploid lines which were tested were different from the diploid line in morphology,sculpture,etc.. 4 of the 5 tested samples were significant larger than the diploid line in size and one was similar to the diploid line. [Conclusion] This research provided references for breeding tetraploid improved varieties of Chrysanthemum cinerariifolium (Trev.) Vis. with good fertility and high germination percentage. 展开更多
关键词 Chrysanthemum cinerariifolium (Trey.) Vis. Tetraploid Pollen grains Fertility
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Ultrastructural Observation of Changes of Polysaccharide Grains in Dormant Shoots of Eucommia ulmoides 被引量:4
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作者 崔克明 罗立新 李正理 《Acta Botanica Sinica》 CSCD 2000年第8期788-793,共6页
Cytochemical and ultrastructural studies indicated that compound spherical bodies observed near the sieve plate in the sieve tube members during the period of cambial dormancy in the shoots of Eucommia ulmoides O... Cytochemical and ultrastructural studies indicated that compound spherical bodies observed near the sieve plate in the sieve tube members during the period of cambial dormancy in the shoots of Eucommia ulmoides Oliv. were polysaccharide bodies different from the polysaccharide grains in other parenchyma cells in shoots, and were similar to cell walls in their staining properties. The compound spherical bodies occurred in the sieve elements during the period of cambial rest and disappeared in the sieve elements during the period of cambial quiescence and activity. 展开更多
关键词 ULTRASTRUCTURE polysaccharide grains sieve tube member DORMANCY Eucommia ulmoides
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Changes in Cooking and Nutrition Qualities of Grains at Different Positions in a Rice Panicle under Different Nitrogen Levels 被引量:15
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作者 DONG Ming-hui SANG Da-zhi WANG Peng WANG Xue-ming YANG Jian-chang 《Rice science》 SCIE 2007年第2期141-148,共8页
Cooking and nutrition qualities of grain are two of the most important aspects of rice quality. To understand the difference in cooking and nutrition qualities among the grains at different positions within a rice pan... Cooking and nutrition qualities of grain are two of the most important aspects of rice quality. To understand the difference in cooking and nutrition qualities among the grains at different positions within a rice panicle, the distributions of gel consistency (GC), amylose content (AC) and crude protein content (CPC) of grains in a panicle in association with different nitrogen levels (0, 120 and 240 k c/ha) were investigated by using two rice varieties, Yangdao 6 (indica) and Wuyujing 3 (japonica). In general, the grains at the basal part of a panicle had lower GC and higher AC than those at the upper or middle part of a panicle. The 1^st grain on the secondary branch with earlier flowering exhibited the highest GC, whereas the 2nd grain on the primary branch with later flowering showed the highest AC. For Yangdao 6, CPC in the grains on the primary branches was lower at the middle part of a panicle than at the upper or basal part of a panicle. For Wuyujing 3, there were no significant differences in CPCs in the grains among the upper, middle and basal parts of a panicle. GC in the grains was increased, whereas AC was reduced from zero nitrogen application (ON) to low amount of nitrogen application (LN), and the result was reversed from LN to medium amount of nitrogen application (MN). CPC was increased with the increase in the amount of nitrogen application. 展开更多
关键词 RICE grain position cooking quality nutrition quality NITROGEN
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Changes in Activities of the Key Enzymes Related to Starch Synthesis in Rice Grains During Grain Filling and Their Relationships with the Filling Rate and Cooking Quality 被引量:17
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作者 ZHAOBu-hong ZHANGWen-jie WANGZhi-qin ZHUQin-sen YANGJian-chang 《Agricultural Sciences in China》 CAS CSCD 2005年第1期26-33,共8页
With 10 rice cultivars (lines) as materials, the changes in activities of adenosine diphosphoglucose pyrophosphorylase(ADPGPase), starch synthase (SSase) and starch branching enzyme (Q-enzyme) in the grains during gra... With 10 rice cultivars (lines) as materials, the changes in activities of adenosine diphosphoglucose pyrophosphorylase(ADPGPase), starch synthase (SSase) and starch branching enzyme (Q-enzyme) in the grains during grain filling, and theirrelationships with the filling rate, gel consistency (GC), alkali spreading value (ASV) and amylose content (AC) werestudied. The results showed that changes in activities of ADPGPase, SSase and Q-enzyme exhibited a single peak duringgrain filling, and the time of the activity peaks for the former two enzymes was earlier than that of the maximum grain-fillingrate (Tmax), and the time reaching the peak for Q-enzyme was synchronous with Tmax. The activities at early grain fillingstage, and the mean and maximum activities of each enzyme during grain filling period were positively and significantly orvery significantly correlated with the mean and maximum grain filling rate and starch content (mg grain-1) in the grains.Activities of ADPGPase at all grain filling stages and those of Q-enzyme at the early and mid filling stages were notsignificantly correlated the cooking quality (GC, ASV and AC). SSase activities at the early filling stage were significantlyand negatively correlated with GC and ASV, and positively correlated with AC. Activities of SSase at mid and late grainfilling stages and Q-enzyme at the late filling stage were significantly and positively correlated with GC and ASV, andnegatively correlated with AC. Spraying zeatin or abscisic acid at early grain filling stage could obviously regulate theactivities of ADPGPase, SSase and Q-enzyme in the grains. 展开更多
关键词 RICE ADPGPase Starch synthase Q-enzyme grain filling rate Cooking quality
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Biochemical Changes Associated with Germinating Rice Grains and Germination Improvement 被引量:16
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作者 Subajiny VELUPPILLAI Ketheeswary NITHYANANTHARAJAH +2 位作者 Seevaratnam VASANTHARUBA Sandrasegarampillai BALAKUMAR Vasanthy ARASARATNAM 《Rice science》 SCIE 2009年第3期240-242,共3页
To determine biochemical changes during the germination of rice grains (Oryza sativa L. subsp, indica var. Mottaikaruppan) and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfa... To determine biochemical changes during the germination of rice grains (Oryza sativa L. subsp, indica var. Mottaikaruppan) and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfate (SDS) (1.0 g/L) and Triton-X-100 (1.0 mL/L)], whole rice grains soaked in distilled water for 12 h at 30℃were germinated in the dark at 30℃ for five days. The highest germination rate (77.1%) was obtained on the 5th day. An increase in the content of reducing sugars from 7.3 to 58.1 mg/g DM (dry matter) was observed from the 1st day of germination. Free amino acids and soluble protein contents increased to 3.69 and 5.29 mg/g DM, respectively on the 5^th day of germination. Total protein content decreased from 100.5 to 91.0 g/kg DM during germination. Increases in amylolytic (1.1 to 190.0 U/g DM) and proteolytic (0 to 0.12 U/g DM) activities were observed during germination. Effects of different concentrations of gibberellic acid on the germination of rice grains were evaluated and 0.1 g/L was found to promote germination. When effects of gibberellic acid (0.1 g/L) and surfactants were evaluated individually and together, higher germination rate was observed in the control experiment (grains germinated in distilled water), whereas giberellic acid and surfactants decreased the germination rate. Therefore, the flour obtained from the grains germinated for four days using distilled water to obtain high content of soluble materials and enzyme activities can be used in preparation of bakery items. 展开更多
关键词 GERMINATION whole rice grains biochemical changes amylase activity protease activity
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Isothermal Growth Kinetics of Ultra-fine Austenite Grains in a Nb-V-Ti Microalloyed Steel 被引量:4
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作者 Shengjie Yao Linxiu Du Xianghua Liu Guodong Wang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2009年第5期615-618,共4页
Ultra-fine austenite grains with size of i-3 μm were prepared in a Nb-V-Ti steel through repetitive treatment of rapid heating and quenching. A model for the growth kinetics of these ultra-fine austenite grains was s... Ultra-fine austenite grains with size of i-3 μm were prepared in a Nb-V-Ti steel through repetitive treatment of rapid heating and quenching. A model for the growth kinetics of these ultra-fine austenite grains was successfully created through successive 2 processes, and the activation energy Q for growth was estimated to be about 693.2 kJ/mol, which directly shows the inhibition effect of microalloy elements on the growth of ultra-fine austenite grains. 展开更多
关键词 Ultra-fine austenite grain grain growth kinetics Microalloyed steel
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Formation and characterization of metallic iron grains in coal-based reduction of oolitic iron ore 被引量:10
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作者 Yong-sheng Sun Yue-xin Han +1 位作者 Yan-feng Li Yan-jun Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第2期123-129,共7页
To reveal the formation and characteristics of metallic iron grains in coal-based reduction, oolitic iron ore was isothermally re- duced in various reduction times at various reduction temperatures. The microstructure... To reveal the formation and characteristics of metallic iron grains in coal-based reduction, oolitic iron ore was isothermally re- duced in various reduction times at various reduction temperatures. The microstructure and size of the metallic iron phase were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and a Bgrimm process mineralogy analyzer. In the results, the re- duced Fe separates from the ore and forms metallic iron protuberances, and then the subsequent reduced Fe diffuses to the protuberances and grows into metallic iron grains. Most of the metallic iron grains exist in the quasi-spherical shape and inlaid in the slag matrix. The cumula- tive frequency of metallic iron grain size is markedly influenced by both reduction time and temperature. With increasing reduction temperature and time, the grain size of metallic iron obviously increases. According to the classical grain growth equation, the growth kinetic parameters, i.e., time exponent, growth activation energy, and pre-exponential constant, are estimated to be 1.3759 ± 0.0374, 103.18 kJ·mol^-1, and 922.05, respec- tively. Using these calculated parameters, a growth model is established to describe the growth behavior of metallic iron grains. 展开更多
关键词 iron ore reduction metallic iron grain size growth kinetics activation energy
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Monitoring Protein and Starch Accumulation in Wheat Grains with Leaf SPAD and Canopy Spectral Reflectance 被引量:6
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作者 TIAN Yong-chao, ZHU yan, CAO Wei-xing, FAN Xue-mei and LIU Xiao-jun(Key Laboratory of Crop Growth Regulation, Ministry of Agriculture/Nanjing Agricultural University,Nanjing 210095, P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2003年第11期1205-1211,共7页
The research was conducted to determine the relationships of protein and starch accumulation dynamics in grains of wheat to post-heading leaf SPAD values and canopy spectral reflectance. The results showed that leaf n... The research was conducted to determine the relationships of protein and starch accumulation dynamics in grains of wheat to post-heading leaf SPAD values and canopy spectral reflectance. The results showed that leaf nitrogen accumulation was exponentially related to leaf SPAD values and linearly related to canopy spectral reflectance, and that there was negative linear relationship between leaf nitrogen accumulation and grain protein accumulation, but positive linear relationship between post-heading leaf nitrogen transloca-tion and grain protein accumulation at maturity. In addition, leaf SPAD values were parabolically related with and ratio indices R(l 500,610)and R(l 220,560)were exponentially related with protein and starch accumulation in grains. These results indicate that leaf SPAD values and canopy spectral reflectance should be good indicators of quality formation dynamics in wheat grains. 展开更多
关键词 WHEAT SPAD Spectral reflectance Ratio index grain quality
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Identification of QTLs associated with cadmium concentration in rice grains 被引量:6
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作者 HU Da-wei SHENG Zhong-hua +8 位作者 LI Qian-long CHEN Wei WEI Xiang-jin XIE Li-hong JIAO Gui-ai SHAO Gao-neng WANG Jian-long TANG Shao-qing HU Pei-song 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第7期1563-1573,共11页
Cadmium(Cd) contamination in rice has been a hot topic of research because of its potential risk to human health. In this study, a double haploid(DH) population derived from Zhongjiazao 17(YK17)(an early-season... Cadmium(Cd) contamination in rice has been a hot topic of research because of its potential risk to human health. In this study, a double haploid(DH) population derived from Zhongjiazao 17(YK17)(an early-season indica cultivar)×D50(a tropical japonica cultivar) was used to identify quantitative trait loci(QTLs) associated with Cd concentration in brown rice(CCBR) and Cd concentration in milled rice(CCMR). Continuous and wide variation for CCBR and CCMR were observed among the DH population. Correlation analysis revealed a positive and highly significant correlation between the two traits. A total of 18 QTLs for CCBR and 14 QTLs for CCMR were identified in five different pot and field trials. Two pairs of QTLs for CCBR(qCCBR2-1 and qCCBR2-2, qCCBR9-1 and qCCBR9-2) and one pair of QTLs for CCMR(qCCMR5-1 and qCCMR5-2) were detected in multiple trials. The alleles increasing CCBR at the qC CBR2-1/qC CBR2-2 and qC CBR9-1/qC CBR9-2 QTLs were contributed by YK17 and D50, respectively, whereas the D50 allele at the qCCMR5-1/qCCMR5-2 QTLs increased CCMR. Eight pairs of QTLs for CCBR and CCMR, qCCBR2-2 and qCCMR2-2, qCCBR3 and qCCMR3, qCCBR4-2 and qCCMR4-1, qCCBR4-3 and qCCMR4-2, qCCBR4-4 and qCCMR4-3, qCCBR5 and qCCMR5-2, qCCBR7 and qCCMR7, and qCCBR11-1 and qCCMR11-2, co-localized on chromosomes 2, 3, 4, 5, 7, and 11, respectively. For all of these QTL pairs, except qCCBR5/qCCMR5-2, the additive effects came from YK17. In addition, four CCMR QTLs showing significant additive×environment interaction and two pairs of CCMR QTLs with bi-allelic epistatic interactions were identified. The results of this study could facilitate marker-assisted selection of breeding rice varieties with low Cd accumulation in grain. 展开更多
关键词 Cd concentration in grain QTL mapping brown rice milled rice
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Description of Aphelenchoides besseyi from Abnormal Rice with ‘Small Grains and Erect Panicles’ Symptom in China 被引量:7
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作者 LIN Mao-song DING Xiao-fan +2 位作者 WANG Zi-ming ZHOU Feng-ming LIN Na 《Rice science》 SCIE 2005年第4期289-294,共6页
The abnormal rice with small grains and erect panicles were found on a large scale in China, which showed shortend rice panicle and decreased number of grains in comparison with normal rice, and the grain was small an... The abnormal rice with small grains and erect panicles were found on a large scale in China, which showed shortend rice panicle and decreased number of grains in comparison with normal rice, and the grain was small and black-brown, and some of them were distorted, while the flag leaf was normal. A kind of nematode of Aphelenchoides was isolated from the grains of rice variety Wuyujing 3 which performed 'small grains and erect panicles' symptom. There were 2014 nematodes in one hundred grains infected, and up to 74 in single grain, 92 percent of the grains tested had nematodes in the infested panicles. The diagnosis characters of nematode include lateral fields about one-fourth as wide as body, with 4 incisures. The terminus bears a mucro of diverse shape with 3-4 pointed processes. The female post-vulval uterine sac extends less than 50% of distance from vulva to anus, no sperm in it. Oocytes usually arrange in 2-4 rows. The male spicules have a moderately developed rostrum. Morphological measurements showed it to be conspecific with Aphelenchoides besseyi Christie, 1942. 展开更多
关键词 Aphelenchoides besseyi abnormal rice with small grains and erect panicles identification NEMATODE nematodiasis
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Changes in Activities of Key Enzymes for Starch Synthesis and Glutamine Synthetase in Grains of Progenies from a Rice Cross During Grain Filling 被引量:3
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作者 LI Xiao-guang LIU Hai-ying +4 位作者 JIN Zheng-xun LIU Hong-liang HUANG Xing XU Mei-lan ZHANG Feng-zhuan 《Rice science》 SCIE 2010年第3期243-246,共4页
The progenies differed in amylose and protein contents in grains, which derived from a rice cross, Dongnong 423×Toukei 180, were used to study changes in the activities of ADP-glucose pyrophosphorylase (AGPP), ... The progenies differed in amylose and protein contents in grains, which derived from a rice cross, Dongnong 423×Toukei 180, were used to study changes in the activities of ADP-glucose pyrophosphorylase (AGPP), soluble starch synthetase (SSS), starch branching enzyme (SBE) and glutamine synthetase (GS) in rice grains during grain filling. The activities of AGPP, SSS and SBE gradually increased and then declined as a single-peak curve with the process of grain filling in the progenies with high and low amylose contents in grains. The progenies with high amylose content peaked earlier in the AGPP, SSS and SBE activities and had higher AGPP, SSS and SBE activities at the early grain filling stage than those with low amylose content. The GS activity peaked earlier and was higher at the late stage of grain filling in the progenies with high protein content than in those with low protein content. It is suggested that the activities of key enzymes for starch synthesis and glutamine synthetase could be changed in oriented breeding for amylose and protein contents in grains. 展开更多
关键词 RICE hybrid progeny grain filling enzyme activity
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The effect of V-Nb on the growth of austenite grains in 17CrNiMo6 gear steel 被引量:5
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作者 Zhao Yaping Wang Maoqiu Yuan Jiguo 《Baosteel Technical Research》 CAS 2008年第2期46-50,共5页
This study researches the effect of V-Nb on the growth of austenite grains in 17CrNiMo6 carburized gear steel. Results show that the carbonitride in V and Nb acts as second-phase particles in the steel, which can be u... This study researches the effect of V-Nb on the growth of austenite grains in 17CrNiMo6 carburized gear steel. Results show that the carbonitride in V and Nb acts as second-phase particles in the steel, which can be used to block the migration of grain boundaries and the thinning of the austenite grains. This causes the crystals in the V-Nb microalloy 17CrNiMo6 steel to coarsen and the temperature to rise, thus reducing the cost of the carbonization that follows processing on the gears. 展开更多
关键词 V-Nb microalloy 17CrNiMo6 steel austenite grain pinning effect
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Cadmium uptake by different rice genotypes that produce white or dark grains 被引量:2
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作者 CUIYu-jing ZHUYortg-guan +1 位作者 F.AndrewSmith SallyE.Smith 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期962-967,共6页
A pot experiment was conducted to investigate cadmium(Cd) uptake by different rice cultivars that produce white or dark grains. Four cultivars with white grains(hereafter, white rice) and five cultivars with dark colo... A pot experiment was conducted to investigate cadmium(Cd) uptake by different rice cultivars that produce white or dark grains. Four cultivars with white grains(hereafter, white rice) and five cultivars with dark colors (hereafter dark rice) were selected for this experiment. Three levels of soil Cd concentrations, background(0), 5 and 10 mg/kg, were used. After harvest, plant biomass, tissue concentrations of Cd, Ca, Fe, Cu and Zn were analyzed. The results showed that Cd concentrations are significantly different between different genotypes, but when comparing the Cd concentrations for the two groups, no significant difference was found. For other divalent cations, Ca concentrations in dark rice were higher than those in white ones(P<0.001 for shoots, P=0.037 for roots); Fe concentrations in dark rice were also higher than those in white ones(P=0.001 either in shoot or root); Zn concentrations in shoot of dark rice were higher than those in white ones, but no significant difference in roots. The total molar concentrations of divalent cations in dark rice were also significantly higher than in white rice. The potential benefit of higher Ca and Fe concentrations in dark rice and similar Cd concentrations in both groups is also discussed in this paper. 展开更多
关键词 CADMIUM nutrient deficiency plant nutrition rice dark grain soil contamination
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Activities of the Enzymes Involved in Starch Synthesis and Starch Accumulation in the Grains of Wheat Cultivars, GC8901 and SN1391 被引量:2
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作者 LIUXia JIANGChun-ming ZHENGZe-rong ZHOUZhu-nan HEMing-rong WANGZhen-lin 《Agricultural Sciences in China》 CAS CSCD 2005年第5期348-354,共7页
Two wheat cultivars, GC8901 (hard winter wheat) and SN1391 (soft winter wheat), were used for investigating the changes of enzyme activities for sucrose metabolism and starch biosynthesis and the accumulation characte... Two wheat cultivars, GC8901 (hard winter wheat) and SN1391 (soft winter wheat), were used for investigating the changes of enzyme activities for sucrose metabolism and starch biosynthesis and the accumulation character of starch composition. The result showed that activities of sucrose (SS), sucrose-phosphate synthase (SPS), adenosine diphosphorate glucose pyrophrylase (AGPase) and soluble starch syntheses (SSS) of 1391, which have more starch, were significant higher than those of 8901, that with low starch content. But the changing of granule-bound starch synthase (GBSS) activity was consistent with the amylose content, which indicated that amylose contents in grain were determined by GBSS activity, especially the activity at later grain filling stages. Simulating with Richards equation showed that it was initiating time and accumulation rate, but not accumulation duration that determined the content of starch composition. Furthermore, changing of sucrose transport capacity was consistent with SSS and GBSS activities, starch accumulation rate was accordant to AGPase and SS/SPS ration, not SS, SPS, SSS or GBSS activities. The results suggested that there was no inevitable relation of starch accumulating rate and starch composition contents with the activity of single enzyme such as SS, SPS, SSS or GBSS, but closely related to AGPase activity and SS/SPS ratio, and it was SPS and AGPase that play a vital role in the biosynthetic pathway. Later polymerization reactions catalyzed by SSS and GBSS don’t seem to control the rate of starch accumulation, but do affect starch structure. 展开更多
关键词 Wheat grain AMYLOSE AMYLOPECTIN Enzymes activities Processing quality
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Characterization of Iron Grains near the P/T Boundary in the Meishan Section of China 被引量:2
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作者 CAI Hou'an LIANG Handong +1 位作者 ZHANG Jun LUO Chunping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期46-51,共6页
The Meishan section of China has been confirmed as the "Global Stratotype Section and Point" of the P/T boundary. In the section, the authors found several types of iron grains, including pyrite, pure iron grains an... The Meishan section of China has been confirmed as the "Global Stratotype Section and Point" of the P/T boundary. In the section, the authors found several types of iron grains, including pyrite, pure iron grains and goethite. From the research of macro minerals, it is easy to find that the grains rich in iron appear from the bottom of the event layer of the section. In other words, it is probably residue of the geochemical catastrophe of that time. Therefore, it is important to trace the source of these iron grains and their relationships, which probably provides evidence for volcanic eruption or impact-volcanoes and has directive significance to the crisis during the P/T transitional period. Through the study of the characterization and relationships of these iron grains, the authors make a preliminary discussion on the P/T mass extinction. 展开更多
关键词 Meishan section P/T boundary PYRITE GOETHITE iron grain
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