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Genetic and Correlation Analysis of Grain Characters in Three-line Hybrid Rice 被引量:11
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作者 邹小云 邓辉明 +6 位作者 傅军如 彭小松 朱昌兰 贺晓鹏 陈小荣 贺浩华 刘宜柏 《Agricultural Science & Technology》 CAS 2009年第2期77-81,共5页
Abst[Objective] This study was to understand the genetic dynamics of three-line hybrid rice, and explore the respective effect of sterile line and restoring line on grain characters of hybrid rica. [Method] Four three... Abst[Objective] This study was to understand the genetic dynamics of three-line hybrid rice, and explore the respective effect of sterile line and restoring line on grain characters of hybrid rica. [Method] Four three-line stedle lines and 27 restoring lines(cultivars) commonly culti- vated in Central China region were regarded as expadmental materials to conduct 4 x27NCII cross design, and the grain characters of three-line hybrid rico were analyzed at genetic and correlation levels. [ Result] Four characters of grain length, grain width, 1 000-grain weight and length- width ratio play the leading role in additive gene effect; these four characters were simultaneously influenced by male parent and female parent, but the effect from male parent was relatively larger. The grain length, grain width, 1 000-grain weight and length-width ratio all have high brood hedtabUities( respectively 99.65%, 98.31%, 95.27% and 98.81% ). Correlation analysis showed that grain length was positively correlated with 1 000-grain weight and length-width ratio at extremely significant level; 1 000-grain weight was positively correlated with grain length and length- width ratio at extremely significant level, and was insignificantly correlated with grain width; grain width was negatively correlated with grain length and length-width ratio at extremely significant level. Path analysis showed that the direct path coefficients of grain length, grain width and 1 0(30- grain weight to length-width ratio were 0.624 6, -0.555 9 and -0.015 8, respectively. [ Conclusion] This study systematically analyzed the effects of stedle line and restoring line on grain characters of hybrid rice, which provided theoretical basis for breeding high quality and yield hy- brid dce. 展开更多
关键词 three-line hybrid dce Grain characters INHERITANCE . Correlation
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Reproduction of the Three-line Genic Male Sterile Line Parent Mian 7MB-1 (Brasscia Napus L.) and Seed Production of F1 Based on Somatic Tissue Culture 被引量:2
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作者 蒙大庆 袁代斌 +7 位作者 张跃非 郭子荣 胥岚 李芝凡 蒲定福 汤天泽 贺启川 陈军 《Agricultural Science & Technology》 CAS 2009年第1期22-25,114,共5页
[Objective] The aim was to study the reproduction of the three-line genic male sterile (GMS) lineparent Mian7MB-1 (B. NapusL.) and the seed production of F1 through somatic tissue culture. [Methed] Through hybridi... [Objective] The aim was to study the reproduction of the three-line genic male sterile (GMS) lineparent Mian7MB-1 (B. NapusL.) and the seed production of F1 through somatic tissue culture. [Methed] Through hybridization, a new breeding material Mian 7MB-1 in three-line genic temporary maintainer line propagated by tissue culture was used to improve the sterile plant rate of rapeseed in dual-purpose recessive GMS line, such as Mian 7AB type, S45AB type, and etc. And then the variety comparative test was performed. [Result] In order to avoid some fertility restoration phenomena occurring during the process of self-reproduction, Mian 7AB was propagated in bulk with somatic tissue culture of temporary maintainer line plant stem. The propagated temporary maintainer line seedlings were applied to the breeding and seed production of net room male sterile line parent, promoting the sterile plant rate of the male sterile line parent to 91.7% -93.5%. The male sterile line parents per hectare were enough for the seed production of hybrid F1 in 7 500 -15 000 hm^2. [ Conclusion ] Compared with the original dual-purpose GMS line, the seed production ultilizing male sterile line with high sterile plant rate greatly reduced the labor, significantly improved the seed yield, ensuring the seed quality and forming a perfect breeding and seed production system. 展开更多
关键词 B. Napus L. Tissue culture three-line GMS Breeding and seed production
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Technical Specification for Producing Hybrid Pepper Seed Using Three-line Male Sterility
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作者 李雪峰 梁成亮 +1 位作者 马艳青 邹学校 《Agricultural Science & Technology》 CAS 2015年第7期1378-1380,1384,共4页
This paper described the whole process of three line hybrid pepper seed production in detail, including requirement of the seed production base, parent culti- vation, field management, and specified the key operation ... This paper described the whole process of three line hybrid pepper seed production in detail, including requirement of the seed production base, parent culti- vation, field management, and specified the key operation techniques in seed pro- duction, such as parental impurity removal to preserve pure state, pollen collection, pollination and seed collecting essentials. This specification is of guiding significance for the production of hybrid pepper seed and ensuring the purity of hybrid pepper seed. 展开更多
关键词 Hybrid Pepper three-line Cytoplasmic male sterility Seed production
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Breeding and Seed Production Techniques of New Aromatic Danxiangyouzhenliang Rice Variety with Good Quality and High Yield
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作者 Riwei HUANG Qiujun LONG +3 位作者 Zishuai SHANG Rihui HUANG Chunliang LIAO Yuechao LUO 《Asian Agricultural Research》 2024年第8期38-41,46,共5页
Danxiangyouzhenliang rice is a high-quality rice variety derived from the hybrid breeding of Danxiang 12A and Xianghuixiangmiao R133.Its unique temperature-sensitive three-line characteristics endow it with significan... Danxiangyouzhenliang rice is a high-quality rice variety derived from the hybrid breeding of Danxiang 12A and Xianghuixiangmiao R133.Its unique temperature-sensitive three-line characteristics endow it with significant advantages of high and stable yield,and its rice fragrance is exquisite and its taste is delicate.Danxiangyouzhenliang rice showed good resistance to rice blast and bacterial blight.On June 10,2021,Danxiangyouzhenliang rice passed the Guangxi Crop Variety Approval(Guishendao 2021074).Danxiangyouzhenliang rice is suitable to be planted as early and late rice in southern,central and northern Guangxi.This study summarized the breeding process and high-yielding seed production techniques of Danxiangyouzhenliang rice,in order to provide useful reference for rice breeders and growers. 展开更多
关键词 Danxiangyouzhenliang RICE SEED production technology HIGH-QUALITY RICE Hybrid BREEDING TEMPERATURE-SENSITIVE three-line
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Studies on the Developmental Genetics of Tiller Number in Three-line Indica Hybrid Rice 被引量:1
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作者 LIANG Kang-jing, LIN Wen-xiong, WANG Xue-ren, CHEN Zhi-xiong, GUO Yu-chun, LIANG Yi-yuan, CHEN Fang-yu and LI Ya-juan( College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, P. R . China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第8期837-844,共8页
Following NCI design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical metho... Following NCI design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical methods. The results showed that dominance effects were predominant for TN. The expression of those additive effects were affected by environment and genotype interaction, but the expression of dominance effects were not affected. Heterosis was the strongest in the middle developmental periods of TN. Additive effects and dominance effects were selectively expressed throughout in the entire tillering developmental stage. Analysis of genetic correlation between TN at different stages and the productive panicles indicated that a close correlation appeared earlier in the populations with higher heterosis than in those with less heterosis. Utilization of heterosis at the middle tillering stage might enhance the final biomass but reduce the percentage of productive panicles. 展开更多
关键词 three-line indica hybrid rice Tiller number Developmental genetics Genetic variance HETEROSIS
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Image Motion Compensation of Off-Axis TMA Three-Line ArrayAerospace Mapping Cameras
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作者 Yongchang Li Pengluo Lu +2 位作者 Longxu Jin Guoning Li Yinan Wu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第6期80-89,共10页
To enhance the image motion compensation accuracy of off-axis three-mirror anastigmatic( TMA)three-line array aerospace mapping cameras,a new method of image motion velocity field modeling is proposed in this paper. F... To enhance the image motion compensation accuracy of off-axis three-mirror anastigmatic( TMA)three-line array aerospace mapping cameras,a new method of image motion velocity field modeling is proposed in this paper. Firstly,based on the imaging principle of mapping cameras,an analytical expression of image motion velocity of off-axis TMA three-line array aerospace mapping cameras is deduced from different coordinate systems we established and the attitude dynamics principle. Then,the case of a three-line array mapping camera is studied,in which the simulation of the focal plane image motion velocity fields of the forward-view camera,the nadir-view camera and the backward-view camera are carried out,and the optimization schemes for image motion velocity matching and drift angle matching are formulated according the simulation results. Finally,this method is verified with a dynamic imaging experimental system. The results are indicative of that when image motion compensation for nadir-view camera is conducted using the proposed image motion velocity field model,the line pair of target images at Nyquist frequency is clear and distinguishable. Under the constraint that modulation transfer function( MTF) reduces by 5%,when the horizontal frequencies of the forward-view camera and the backward-view camera are adjusted uniformly according to the proposed image motion velocity matching scheme,the time delay integration( TDI) stages reach 6 at most. When the TDI stages are more than 6,the three groups of camera will independently undergo horizontal frequency adjustment. However, when the proposed drift angle matching scheme is adopted for uniform drift angle adjustment,the number of TDI stages will not exceed 81. The experimental results have demonstrated the validity and accuracy of the proposed image motion velocity field model and matching optimization scheme,providing reliable basis for on-orbit image motion compensation of aerospace mapping cameras. 展开更多
关键词 three-line array mapping camera off-axis TMA image motion compensation image motion velocity drift angle
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Vision-based Localization from Three-Line Structures (TLS)
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作者 Zhao-Zheng Hu Na Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第3期48-55,共8页
This paper presents a novel vision based localization algorithm from three-line structure ( TLS) .Two types of TLS are investigated: 1) three parallel lines ( Structure I) ; 2) two parallel lines and one orthogonal li... This paper presents a novel vision based localization algorithm from three-line structure ( TLS) .Two types of TLS are investigated: 1) three parallel lines ( Structure I) ; 2) two parallel lines and one orthogonal line ( Structure II) .From single image of either structure,the camera pose can be uniquely computed for vision localization.Contributions of this paper are as follows: 1 ) both TLS structures can be used as simple and practical landmarks,which are widely available in daily life; 2) the proposed algorithm complements existing localization methods,which usually use complex landmarks,especially in the partial blockage conditions; 3) compared with the general Perspective-3-Lines ( P3L) problem,camera pose can be uniquely computed from either structure.The proposed algorithm has been tested with both simulation and real image data.For a typical simulated indoor condition ( 75 cm-size landmark,less than 7.0 m landmark-to-camera distance,and 0.5-pixel image noises) ,the means of localization errors from Structure I and Structure II are less than 3.0 cm.And the standard deviations are less than 3.0 cm and 1.5 cm,respectively.The algorithm is further validated with two actual image experiments.Within a 7.5 m × 7.5 m indoor situation,the overall relative localization errors from Structure I and Structure II are less than 2.2% and 2.3% ,respectively,with about 6.0 m distance.The results demonstrate that the algorithm works well for practical vision localization. 展开更多
关键词 vision-based localization three-line structure camera pose computer vision
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COMPLEX INTERPOLATION OF L_(p)(C,H)SPACES WITH RESPECT TO CULLEN-REGULAR
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作者 Kaili HE Jianxun HE Zhenzhen LOU 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期774-788,共15页
The aim of this paper is to prove a new version of the Riesz-Thorin interpolation theorem on L^(P)(C,H).In the sense of Cullen-regular,we show Hadamard’s three-lines theorem by means of the Maximum modulus principle ... The aim of this paper is to prove a new version of the Riesz-Thorin interpolation theorem on L^(P)(C,H).In the sense of Cullen-regular,we show Hadamard’s three-lines theorem by means of the Maximum modulus principle on a symmetric slice domain.In addition,two applications of the Riesz-Thorin theorem are presented.Finally,we investigate two kinds of Calderón’s complex interpolation methods in LP(C,H). 展开更多
关键词 Hadamard’s three-lines theorem complex interpolation quaternion valued function space Cullen-regular
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On Significance of Heterotic Group Theory in Hybrid Rice Breeding 被引量:7
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作者 Lu Zuo-mei Xu Bao-qin 《Rice science》 SCIE 2010年第2期94-98,共5页
Heterotic group theory (HGT) has played a major role in supporting hybrid maize breeding for about 100 years. The basic content and studies of HGT, and its application in rice and maize were summarized in this paper... Heterotic group theory (HGT) has played a major role in supporting hybrid maize breeding for about 100 years. The basic content and studies of HGT, and its application in rice and maize were summarized in this paper. Additionally, difficulties and challenges for hybrid rice breeding in China were analyzed, and necessity and urgency in hybrid rice breeding by using HGT were proposed. 展开更多
关键词 hybrid rice hybrid maize BREEDING three-line system combining ability heterotic group crossing model
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Status and Prospects of Hybrid Rice Breeding in Jiangsu, China 被引量:2
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作者 WANG Cai-lin 《Rice science》 SCIE 2005年第3期219-225,共7页
Research on hybrid rice in Jiangsu Province, China began in 1970. Great progress has been made since then, which can be divided into three stages according to the development of hybrid rice breeding and production in ... Research on hybrid rice in Jiangsu Province, China began in 1970. Great progress has been made since then, which can be divided into three stages according to the development of hybrid rice breeding and production in Jiangsu Province. The first stage was beginning stage from 1970 to 1980, when progress was mainly made in cytoplasmic male sterile line breeding. The second stage could be described as developing stage, from 1980 to 1995, when indica hybrid rice was rapidly popularized, and japonica hybrid rice became popular later. From 1996, hybrid rice breeding in Jiangsu Province entered the third stage, when both indica and japonica hybrid rice breeding in the three-line system or intersubspecific hybrid rice breeding in the two-line system made a great breakthrough with the successful breeding of the hybrids Feyou 559, 9 You 138 and Liangyoupeijiu. The developing trend of hybrid rice breeding in Jiangsu Province is also discussed. 展开更多
关键词 hybrid rice (Oryza sativa) BREEDING three-line system two-line system indica-japonica hybridization HETEROSIS
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Fertility Expression of TGMS-Genes in the Backgrounds of indica CMS-lines,B-lines and R-lines of Hybrid Rice 被引量:1
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作者 WANG Ji-feng Lu Zuo-mei 《Rice science》 SCIE 2006年第4期243-249,共7页
The generation fertility of 51 F1, 19 F2 and 6 BC1 between 3 thermo-sensitive genic male sterile lines (TGMS-lines) Pei'ai 64S, 6311S and 360S, and the three lines of hybrid rice including 7 indica cytoplasmic male... The generation fertility of 51 F1, 19 F2 and 6 BC1 between 3 thermo-sensitive genic male sterile lines (TGMS-lines) Pei'ai 64S, 6311S and 360S, and the three lines of hybrid rice including 7 indica cytoplasmic male sterile lines (CMS-lines) and their corresponding maintainer lines (B-lines) and 3 indica restorer lines (R-lines) were investigated to study the expression of TGMS-genes in the backgrounds of the three lines of hybrid rice. Pei'ai 64S has stronger fertility restoring (Rf) genes for CMS-lines and its TGMS trait is governed by 2 pairs of independent recessive genes; The TGMS trait of 6311S is governed by a single recessive gene with weaker Rf-gene in 6311S and the TGMS trait of 360S is governed by a single recessive gene with no Rf-gene in 360S. The investigation on the fertility of F1 plants between 5 CMS-lines and 4 TGMS generations selected from F2 plants of 4 CMS-lines x 6311S confirmed that the expression of TGMS-gene was controlled by Rf-gene in the genetic background of cytoplasm of CMS-lines, but not affected by Rf-gene in the genetic background of normal fertile cytoplasm. The potential breeding strategies of TGMS-lines with cytoplasm of CMS-lines and CMS-lines with the nucleus of TGMS-genes were discussed. 展开更多
关键词 thermo-sensitive genic male sterility-gene three-line system genetic background gene expression restorer gene
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A FAST SEARCH METHOD OF STEERED RESPONSE POWER WITH SMALL-APERTURE MICROPHONE ARRAY FOR SOUND SOURCE LOCALIZATION 被引量:1
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作者 Zhao Xiaoyan Tang Jie +1 位作者 Zhou Lin Wu Zhenyang 《Journal of Electronics(China)》 2013年第5期483-490,共8页
The Steered Response Power(SRP)method works well for sound source localization in noisy and reverberant environment.However,the large computation complexity limits its practical application.In this paper,a fast SRP se... The Steered Response Power(SRP)method works well for sound source localization in noisy and reverberant environment.However,the large computation complexity limits its practical application.In this paper,a fast SRP search method is proposed to reduce the computational complexity using small-aperture microphone array.The proposed method inspired by the SRP spatial spectrum includes two steps:first,the proposed method estimates the azimuth of the sound source roughly and determines whether the sound source is in far field or near field;then,different fine searching operations are performed according to the sound source being in far field or near field.Experiments both in simulation environments and real environments have been performed to compare the localization accuracy and computation complexity of the proposed method with those of the conventional SRP-PHAT algorithm.The results show that,the proposed method has a comparative accuracy with the conventional SRP algorithm,and achieves a reduction of 93.62%in computation complexity compared to the conventional SRP algorithm. 展开更多
关键词 Sound source localization Steered Response Power(SRP) three-line method Smallaperture microphone array
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Breeding double low super hybrids with dominant genic male sterility three lines in Brassica napus
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作者 王茂林 Zhao Yun 《High Technology Letters》 EI CAS 2005年第4期427-431,共5页
A double low homozygous two-type sterile line ZY-2AB, its near-isogenic temporary maintainer line ZY-4, and the full sterile line ZY-3 derived from the cross of ZY-2A with ZY-4, were developed to breed three-line domi... A double low homozygous two-type sterile line ZY-2AB, its near-isogenic temporary maintainer line ZY-4, and the full sterile line ZY-3 derived from the cross of ZY-2A with ZY-4, were developed to breed three-line dominant GMS hybrid in Brassica napus. Three years data showed that the ratios of sterile and fertile plants fit the expected 1 : 1 ratio in ZY-2AB, and the 1:0 ratio in ZY-3, respectively. Some double low super hybrid combinations were screened out when the full sterile line ZY-3 was used as female parent, among which the combination 01Z24 increased 36.88 percent more yield than control and the conbination 98Z131 has been passed through the Sichuan Provincial Regional Test and registered in Sichuan Province. Two years data showed that the agronomic performance of the two-line hybrids derived from crosses of ZY-2A with restorer lines versus that of the three-line hybrids produced by ZY-3 was not different for any of the nine most important agronomic characteristics, revealing that near-isogenic line of homozygous two-type line was used as temporary maintainer could effectively avoid the disadvantage of threeway cross hybrid in breeding three-line dominant GMS hybrid. 展开更多
关键词 Brassica napus HYBRID dominant genic male sterility three-line
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Chloroplast DNA Polymorphism in Rice (<i>Oryza sativa</i>L.)
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作者 Houxiong Wu Lifang Pu +4 位作者 Yiji Shu Yifeng Li Jie Meng Hua Yang Huan Zhao 《American Journal of Plant Sciences》 2020年第3期454-464,共11页
We analyzed the sequence alignment on 25 AA rice and 24 non-AA rice chloroplasts using two length diversity markers (ORF 100 and ORF29-TrnCGCA) and four sequence markers existed in introns of rps16 gene and TrnTUGU-Tr... We analyzed the sequence alignment on 25 AA rice and 24 non-AA rice chloroplasts using two length diversity markers (ORF 100 and ORF29-TrnCGCA) and four sequence markers existed in introns of rps16 gene and TrnTUGU-TrnLUAA spacer to explore the chloroplast diversity of different types of rice using PCR amplification and sequencing. Results showed that in terms of the length of ORF100 and ORF29-TrnCGCA, chloroplast DNA (cp DNA) of Hainan ordinary wild rice, Dongxiang ordinary wild rice, Hepu ordinary wild rice and three-line cytoplasmic male sterile wild rice were indica-type, Chaling ordinary wild rice, Fusui ordinary wild rice, Niwara wild rice, Brazilian upland rice and Lemont were japonica-type among in AA genome. Besides, all non-AA wild rice was japonica-type. There were 4 indica-japonica markers utilizing introns of rps16 gene and TrnTUGU-TrnLUAA. We found that all the ordinary wild rice in Chaling and Fusui of AA genome presented as japonica specific sites, while the others owned two indica and japonica specific sites, respectively. There were two indica-japonica sites separately and a 6-base specific fragment in three-line cytoplasmic male sterile materials except Yuetai A, simultaneously, 2-base difference from Hainan wild rice. Moreover, Brazilian upland rice and Lemont were entire japonica specific sites. Result of three markers indicated that the cp DNA of non-AA wild rice was japonica-type and result of one marker showed indica-type. Sequencing results also suggested that wild rice existed many polymorphic base sites, CCDD genome, wart wild rice and malay wild rice had their own specific sites. In conclusion, significant differentiation trend of indica-japonica exhibits in chloroplast of ordinary wild rice, and non-AA wild rice is generally japonica-type. The cytoplasmic polymorphism level of three-line sterile lines is low. It is worth considering whether the cytoplasm of Honglian-type sterile line Yuetai A comes from Hainan ordinary wild rice. Furthermore, genetic polymorphisms in wild rice are far more than in cultivar. 展开更多
关键词 RICE CHLOROPLAST DNA three-line STERILE RICE Wild RICE POLYMORPHISM
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High-yielding Seed Production Techniques of New Hybrid Rice Combination-Chuanxiang No.2058
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作者 王国忠 鹿占黔 +4 位作者 陈恩瑞 肖乾一 周国富 邓忠伦 陈祖国 《Agricultural Science & Technology》 CAS 2015年第7期1415-1417,1420,共4页
Chuanxiang No.2058 is a new combination of three-line late indica hybrid rice bred based on sterile line Chuanxiang 29A and restorer Qiannanhui No.2058. In order to promote its application, seed production techniques ... Chuanxiang No.2058 is a new combination of three-line late indica hybrid rice bred based on sterile line Chuanxiang 29A and restorer Qiannanhui No.2058. In order to promote its application, seed production techniques of Chuanxiang No.2058 were explored during 2009-2010. The research detailed the seed production tech- niques from selection of seed production bases, rational arrangement of sowing gap stage, seedling cultivation in different stages, scientific arrangement of male/female parents, management of fertilizer and water, adjustment of florescence, artificial pol- lination, comprehensive treatment of disease and pest damages, and timely control- ling of abnormal and poorly-qualified rice. 展开更多
关键词 three-line late indica hybrid rice Chuanxiang No.2058 Seed productiontechniques
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High-yield Production Techniques of High-quality and Early Maturity Hybrid Rice Xiangzaoyou 2017
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作者 Guozhong WANG Naiqiao HONG +3 位作者 Guofu ZHOU Qianyi XIAO Enrui CHEN Yi ZHOU 《Agricultural Biotechnology》 CAS 2018年第6期32-34,40,共4页
Xiangzaoyou 2017 is an excellent early maturing variety bred from the combination of Neixiang 3A and the self-fertile restorer QN 2017 by Qiannan Institute of Agricultural Sciences of Guizhou Province,and it has been ... Xiangzaoyou 2017 is an excellent early maturing variety bred from the combination of Neixiang 3A and the self-fertile restorer QN 2017 by Qiannan Institute of Agricultural Sciences of Guizhou Province,and it has been approved by the Guizhou Crop Variety Approval Committee( Approval No.: Qianshendao 2006001).In order to promote its application in production,the research on the seed production techniques of Xiangzaoyou 2017 was carried out,and the key technical points of high-yield seed production of Xiangzaoyou 2017 were put forward. 展开更多
关键词 three-line HYBRID RICE Xiangzaoyou 2017 SEED PRODUCTION TECHNIQUE
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Hybrid Rice Research and Development in China and Its New Progress
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作者 Luo Runliang (China National Hybrid Rice R&D Center, Changsha 410125) 《Hunan Agricultural Science & Technology Newsletter》 2000年第3期5-12,共8页
Hybrid rice's history and its development up to date are described in the paper. Compared with the conventional rice, hybrid rice can increase grain yield by about 20%. Hybrid rice breeding in China has been advan... Hybrid rice's history and its development up to date are described in the paper. Compared with the conventional rice, hybrid rice can increase grain yield by about 20%. Hybrid rice breeding in China has been advancing along the three-line method, to two-line method, to super high-yielding rice application strategically and its success in higher degree will be seen by the utilization of distant heterosis cooperated with biotechnology. 展开更多
关键词 Hybrid rice three-line method Two-line method Super rice Distant heterosis BIOTECHNOLOGY
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Compact input-reflectionless balanced bandpass filter with flexible bandwidth using three-line coupled structure
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作者 Yahui ZHU Jing CAI +2 位作者 Wei QIN Wenwen YANG Jianxin CHEN 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2023年第2期314-326,共13页
A compact input-reflectionless balanced bandpass filter(BPF)with flexible bandwidth(BW)using a three-line coupled structure(TLCS)is presented in this paper.For the differential mode(DM),the TLCS is applied to achieve ... A compact input-reflectionless balanced bandpass filter(BPF)with flexible bandwidth(BW)using a three-line coupled structure(TLCS)is presented in this paper.For the differential mode(DM),the TLCS is applied to achieve the bandpass response;meanwhile,the input coupled-feed line of the TLCS is reused in the input absorption network.This design shows a good fusion of the absorptive and BPF sections,effectively reducing the circuit size,and the BWs of the two sections that can be controlled separately result in a flexibly controllable DM response BW of the proposed input-reflectionless balanced BPF.Detailed analyses of the ratio of the two-part BWs have been given for the first time,which is vital for the passband flatness and reflectionless feature.In the codesign of this work,the input-reflectionless DM bandpass response can be optimized easily,while wideband common mode(CM)noise absorption is achieved by the input absorption network.To verify the design method,a prototype with a compact layout(0.52λ×0.36λ)is designed and measured in the 0-7.0 GHz range.The DM center frequency(f0)is 2.45 GHz with a measured 3 dB fractional bandwidth of 31.4%.The simulation and measurement results with good agreement are presented,showing good performance,e.g.,low insertion loss(0.43 dB),wide upper stopband for the DM bandpass response(over 20 dB rejection level up to 2.72f0),and wideband DM reflectionless and CM noise absorption(fractional absorption bandwidth of 285.7%). 展开更多
关键词 Input-reflectionless filter Balanced bandpass filter(BPF) Differential mode(DM) Common mode(CM) three-line coupled structure(TLCS)
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