This study was conducted to develop and characterize a novel cytoplasmic male sterile （CMS） source which was identified from Dongxiang wild rice （Oryza rufipogon） by crossing Dongxiang wild rice as female with Zho...This study was conducted to develop and characterize a novel cytoplasmic male sterile （CMS） source which was identified from Dongxiang wild rice （Oryza rufipogon） by crossing Dongxiang wild rice as female with Zhongzao 35, an indica inbred variety, as male and continuous backcrossing with Zhongzao 35. Observation under optical microscope manifested that this novel CMS belonged to typical abortion type with less pollen compared with wild abortive type cytoplasm （CMS-WA）. Sequential planting showed that this novel CMS has complete and stable male sterility. Testcross experiment showed that all the 24 tested materials including maintainer and restorer lines of CMS-WA and Honglian type cytoplasm （CMS-HL） and other indica inbred varieties are the maintainers with complete maintaining ability, suggesting that this novel CMS has fertility restoration totally different from CMS-WA and CMS-HL and belongs to a novel type of CMS. So far, we only discovered a unique fertility restoration source for this novel CMS. Inheritance analysis showed that the fertility restoration of this CMS was governed by three pairs of independent dominant genes. Prospect for application of this novel CMS system in hybrid rice breeding was also discussed.展开更多
The use of cytoplasm male sterility （CMS） is crucial for three-line hybrid seed production. Two types of CMS have been discovered from Dongxiang wild rice, namely the wild abortion type CMS （CMS-WA） and the Dongxi...The use of cytoplasm male sterility （CMS） is crucial for three-line hybrid seed production. Two types of CMS have been discovered from Dongxiang wild rice, namely the wild abortion type CMS （CMS-WA） and the Dongxiang wild type CMS （CMS-DW）. In this study, we show the molecular identification of the two types of CMS in Dongxiang wild rice. WA352, which conferred CMS-WA, was not detected in Dongxiang wild iice, implying Dongxiang wild rice does not carry the CMS- WA source. Further analysis of WA352 in DYIA, a CMS-DW line, by PCR amplification and sequencing, revealed two insertion-deletion polymorphisms occurred in CMS-DW compared to WA352 of CMS-WA. It was reported that WA352 was comprised of an unknown origin sequence and partial sequences of three open reading frames （ORFs）, orf284, orf224 and orf288. The 42-bp insertion was located between the two segments of orf224 and orf288, which created a new chimeric ORF, orf216. This new ORF was also detected in CMS-HL. Based on the 9-bp deletion in orf284, a specific mitochon- drial marker of DW-M1 was developed, which could be used to specifically distinguish the DW-type source. Moreover, semi-quantitative RT-PCR analysis preliminarily suggested that both orf216 and orf284 could be considered as candidates for CMS-DW. These findings present a preliminary understanding of CMS-DW at the molecular level.展开更多
Deep rooting is an important trait in rice drought resistance.Genetic resources of deep-rooting varieties are valuable in breeding of water-saving and drought-resistant rice.In the present study,234BC2F7 backcross int...Deep rooting is an important trait in rice drought resistance.Genetic resources of deep-rooting varieties are valuable in breeding of water-saving and drought-resistant rice.In the present study,234BC2F7 backcross introgression lines were derived from a cross of Dongye 80(an accession of Dongxiang wild rice as the donor parent)and R974(an indica restorer line as the recurrent parent).A genetic linkage map containing 1977 bin markers was constructed by ddRADSeq for QTL analysis.Thirty-one QTLs for four root traits(the number of deep roots,the number of shallow roots,the total number of deep roots and the ratio of deep roots)were assessed on six rice chromosomes in two environments(2020 Shanghai and 2021 Hainan).Two of the QTLs,qDR5.1 and qTR5.2,were located on chromosome 5 in a 70-kb interval.They were detected in both environments.qDR5.1 explained 13.35%of the phenotypic variance in 2020 Shanghai and 12.01%of the phenotypic variance in 2021 Hainan.qTR5.2 accounted for 10.88%and 10.93%of the phenotypic variance,respectively.One QTL(qRDR2.2)for the ratio of deep roots was detected on chromosome 2 in a 210-kb interval and accounted for 6.72%of the phenotypic variance in 2020.The positive effects of these three QTLs were all from Dongxiang wild rice.Furthermore,nine and four putative candidate genes were identified in qRDR2.2 and qDR5.1/qTR5.2,respectively.These findings added to our knowledge of the genetic control of root traits in rice.In addition,this study will facilitate the future isolation of candidate genes of the deep-rooting trait and the utilization of Dongxiang wild rice in the improvement of rice drought resistance.展开更多
A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper res...A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper resistance and yield traits. A linkage map consisting of 119 DNA markers and spanned for 1188 cM over the 12 rice chromosomes was constructed. Thirty-two chromosomal segment substitution lines were selected based on the percentage of Xieqingzao B allele at marker loci. These lines are of great potential for gene mapping and alien gene introgression.展开更多
The inheritance of the sterility maintenance ability was studied for three types of CMS lines (Zhenshan97A, XieqingzaoA and II-32A) and several lines in indica rice. The result showed that the abilities to keep the ma...The inheritance of the sterility maintenance ability was studied for three types of CMS lines (Zhenshan97A, XieqingzaoA and II-32A) and several lines in indica rice. The result showed that the abilities to keep the male sterility of the maintainer lines strengthened obviously with the progressive backcrossing. The critical stage to maintain the sterility of CMS lines happened usually in BC5-6 generation. The selection of the recurrent parent gave an obvious influence on the pollen fertility distribution of the later generations. The author has discussed ways of improving of the maintainer lines.展开更多
Five cytoplasmic male sterile （CMS） lines were used as parents in an incomplete diallet cross and six restorer lines of rice design （Nc II design）. Thirty hybrid combinations with the same growth period were selec...Five cytoplasmic male sterile （CMS） lines were used as parents in an incomplete diallet cross and six restorer lines of rice design （Nc II design）. Thirty hybrid combinations with the same growth period were selected as experimental ma- terials to investigate the heterosis, combined ability and heredity of Cd content in brown rice of indica hybrid rice. According to the results, Cd content in brown rice showed a significantly negative heterosis; the general combining ability and specific combination ability of Cd content in CMS and restorer lines both reached extremely significant level （P〈0.01）, indicating that both genetic improvement of parents and e- valuation of combinations are important to the breeding of hybrid combinations with low accumulation of Cd; the broad-sense heritabitity and narrow-sense heritability of Cd content were both relatively high with slight differences, which respectively reached 97.73% and 80.10%, indicating that Cd content in brown rice mainly de- pends on the additive action of genes; in addition, parent improvement showed bet- ter effect on the selection of early generation.展开更多
[目的]本文旨在分析播栽温度对水稻野败型细胞质雄性不育性(wild abortive type cytoplasmic male sterility,CMS-WA)的影响,为不育系选育、提纯、繁殖和制种提供理论依据。[方法]设置16.8、21.2、24.5、27.3、30.1℃5个播栽温度,在自...[目的]本文旨在分析播栽温度对水稻野败型细胞质雄性不育性(wild abortive type cytoplasmic male sterility,CMS-WA)的影响,为不育系选育、提纯、繁殖和制种提供理论依据。[方法]设置16.8、21.2、24.5、27.3、30.1℃5个播栽温度,在自然温度梯度压力下,选择3个不同微效恢复基因数量的野败型(wild abortion type,WA)不育系珍汕97A、龙特浦A和京福1A,以嵌合颖花率和黑染花粉率为指标进行对比研究,应用回归模型和主效可加互作可乘模型(additive main effects and multiplicative interaction,AMMI),分析不育系花粉育性的变化动态。[结果]随着播栽期的推迟,不育系播始历期缩短,生育进程加快,有效积温总体呈先升后降趋势,表现感温性。播栽温度在20.1~30.1℃时能提高不育系黑染花粉率和嵌合颖花率,呈正效应。随着播栽温度的上升,3个不育系的黑染花粉率和嵌合颖花率总体上均表现上升趋势,龙特浦A响应极显著,京福1A和珍汕97A表现不显著。珍汕97A花粉育性平均值较低,黑染花粉率和嵌合颖花率分别为1.398%和5.628%,其基因型互作效应主成分轴(interaction principal component axis,ICPA1)值分别为-1.632和-1.512,表明其不育性稳定,花粉育性对播栽温度敏感度低;龙特浦A和京福1A花粉育性平均值较高,二者的黑染花粉率分别为9.836%和7.580%,嵌合颖花率分别为14.788%和11.810%,黑染花粉率基因型IPCA1数值分别为1.114和0.518,嵌合颖花率基因型IPCA1数值分别为0.133和1.379,表明其不育性较不稳定,花粉育性对播栽温度变化相对敏感。[结论]根据温度对不育系育性影响的变化规律,对于温度敏感型的不育系,宜采取早繁早制的措施,保证种子纯度。在不育系选育和遗传提纯上,应在微效恢复基因高效表达的温度条件下进行,可及早剔除不合格单株或株系,以获得不育性较稳定后代。展开更多
基金supported by the Key Program for Scienceand Technology of Jiangxi ProvinceChina(Grant No.20114ABF03101)+1 种基金the Program of Advantage Group forInnovation of Science and Technology of Jiangxi ProvinceChina(Grant No.20115BCB29019)
文摘This study was conducted to develop and characterize a novel cytoplasmic male sterile （CMS） source which was identified from Dongxiang wild rice （Oryza rufipogon） by crossing Dongxiang wild rice as female with Zhongzao 35, an indica inbred variety, as male and continuous backcrossing with Zhongzao 35. Observation under optical microscope manifested that this novel CMS belonged to typical abortion type with less pollen compared with wild abortive type cytoplasm （CMS-WA）. Sequential planting showed that this novel CMS has complete and stable male sterility. Testcross experiment showed that all the 24 tested materials including maintainer and restorer lines of CMS-WA and Honglian type cytoplasm （CMS-HL） and other indica inbred varieties are the maintainers with complete maintaining ability, suggesting that this novel CMS has fertility restoration totally different from CMS-WA and CMS-HL and belongs to a novel type of CMS. So far, we only discovered a unique fertility restoration source for this novel CMS. Inheritance analysis showed that the fertility restoration of this CMS was governed by three pairs of independent dominant genes. Prospect for application of this novel CMS system in hybrid rice breeding was also discussed.
基金supported by the National Natural Science Foundation of China (31460343)the Key Program for Science and Technology of Jiangxi Province, China (20152ACF60015)
文摘The use of cytoplasm male sterility （CMS） is crucial for three-line hybrid seed production. Two types of CMS have been discovered from Dongxiang wild rice, namely the wild abortion type CMS （CMS-WA） and the Dongxiang wild type CMS （CMS-DW）. In this study, we show the molecular identification of the two types of CMS in Dongxiang wild rice. WA352, which conferred CMS-WA, was not detected in Dongxiang wild iice, implying Dongxiang wild rice does not carry the CMS- WA source. Further analysis of WA352 in DYIA, a CMS-DW line, by PCR amplification and sequencing, revealed two insertion-deletion polymorphisms occurred in CMS-DW compared to WA352 of CMS-WA. It was reported that WA352 was comprised of an unknown origin sequence and partial sequences of three open reading frames （ORFs）, orf284, orf224 and orf288. The 42-bp insertion was located between the two segments of orf224 and orf288, which created a new chimeric ORF, orf216. This new ORF was also detected in CMS-HL. Based on the 9-bp deletion in orf284, a specific mitochon- drial marker of DW-M1 was developed, which could be used to specifically distinguish the DW-type source. Moreover, semi-quantitative RT-PCR analysis preliminarily suggested that both orf216 and orf284 could be considered as candidates for CMS-DW. These findings present a preliminary understanding of CMS-DW at the molecular level.
基金supported by the National Modern Agricultural Industry Technology System Construction Program of China(Grant No.20212BBF63001)the Open Competition Program of Jiangxi Provincial Science and Technology in China(Grant No.20213AAF01001)+2 种基金the Jiangxi Provincial Science and Technology Support Program in China(Grant No.20203BBF63033)the Jiangxi Modern Agricultural Research Collaborative Innovation Project in China(Grant No.JXXTCX202111)the Open Project of State Key Laboratory of Rice Biology in China(Grant No.20200101)。
文摘Deep rooting is an important trait in rice drought resistance.Genetic resources of deep-rooting varieties are valuable in breeding of water-saving and drought-resistant rice.In the present study,234BC2F7 backcross introgression lines were derived from a cross of Dongye 80(an accession of Dongxiang wild rice as the donor parent)and R974(an indica restorer line as the recurrent parent).A genetic linkage map containing 1977 bin markers was constructed by ddRADSeq for QTL analysis.Thirty-one QTLs for four root traits(the number of deep roots,the number of shallow roots,the total number of deep roots and the ratio of deep roots)were assessed on six rice chromosomes in two environments(2020 Shanghai and 2021 Hainan).Two of the QTLs,qDR5.1 and qTR5.2,were located on chromosome 5 in a 70-kb interval.They were detected in both environments.qDR5.1 explained 13.35%of the phenotypic variance in 2020 Shanghai and 12.01%of the phenotypic variance in 2021 Hainan.qTR5.2 accounted for 10.88%and 10.93%of the phenotypic variance,respectively.One QTL(qRDR2.2)for the ratio of deep roots was detected on chromosome 2 in a 210-kb interval and accounted for 6.72%of the phenotypic variance in 2020.The positive effects of these three QTLs were all from Dongxiang wild rice.Furthermore,nine and four putative candidate genes were identified in qRDR2.2 and qDR5.1/qTR5.2,respectively.These findings added to our knowledge of the genetic control of root traits in rice.In addition,this study will facilitate the future isolation of candidate genes of the deep-rooting trait and the utilization of Dongxiang wild rice in the improvement of rice drought resistance.
文摘A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B / Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper resistance and yield traits. A linkage map consisting of 119 DNA markers and spanned for 1188 cM over the 12 rice chromosomes was constructed. Thirty-two chromosomal segment substitution lines were selected based on the percentage of Xieqingzao B allele at marker loci. These lines are of great potential for gene mapping and alien gene introgression.
基金supported by a grant from China Key Technology Program and Zhejiang province‘8812’Program.
文摘The inheritance of the sterility maintenance ability was studied for three types of CMS lines (Zhenshan97A, XieqingzaoA and II-32A) and several lines in indica rice. The result showed that the abilities to keep the male sterility of the maintainer lines strengthened obviously with the progressive backcrossing. The critical stage to maintain the sterility of CMS lines happened usually in BC5-6 generation. The selection of the recurrent parent gave an obvious influence on the pollen fertility distribution of the later generations. The author has discussed ways of improving of the maintainer lines.
基金Supported by Youth Fund Project of Sichuan Academy of Agricultural Sciences(2009QNJJ015)~~
文摘Five cytoplasmic male sterile （CMS） lines were used as parents in an incomplete diallet cross and six restorer lines of rice design （Nc II design）. Thirty hybrid combinations with the same growth period were selected as experimental ma- terials to investigate the heterosis, combined ability and heredity of Cd content in brown rice of indica hybrid rice. According to the results, Cd content in brown rice showed a significantly negative heterosis; the general combining ability and specific combination ability of Cd content in CMS and restorer lines both reached extremely significant level （P〈0.01）, indicating that both genetic improvement of parents and e- valuation of combinations are important to the breeding of hybrid combinations with low accumulation of Cd; the broad-sense heritabitity and narrow-sense heritability of Cd content were both relatively high with slight differences, which respectively reached 97.73% and 80.10%, indicating that Cd content in brown rice mainly de- pends on the additive action of genes; in addition, parent improvement showed bet- ter effect on the selection of early generation.
文摘[目的]本文旨在分析播栽温度对水稻野败型细胞质雄性不育性(wild abortive type cytoplasmic male sterility,CMS-WA)的影响,为不育系选育、提纯、繁殖和制种提供理论依据。[方法]设置16.8、21.2、24.5、27.3、30.1℃5个播栽温度,在自然温度梯度压力下,选择3个不同微效恢复基因数量的野败型(wild abortion type,WA)不育系珍汕97A、龙特浦A和京福1A,以嵌合颖花率和黑染花粉率为指标进行对比研究,应用回归模型和主效可加互作可乘模型(additive main effects and multiplicative interaction,AMMI),分析不育系花粉育性的变化动态。[结果]随着播栽期的推迟,不育系播始历期缩短,生育进程加快,有效积温总体呈先升后降趋势,表现感温性。播栽温度在20.1~30.1℃时能提高不育系黑染花粉率和嵌合颖花率,呈正效应。随着播栽温度的上升,3个不育系的黑染花粉率和嵌合颖花率总体上均表现上升趋势,龙特浦A响应极显著,京福1A和珍汕97A表现不显著。珍汕97A花粉育性平均值较低,黑染花粉率和嵌合颖花率分别为1.398%和5.628%,其基因型互作效应主成分轴(interaction principal component axis,ICPA1)值分别为-1.632和-1.512,表明其不育性稳定,花粉育性对播栽温度敏感度低;龙特浦A和京福1A花粉育性平均值较高,二者的黑染花粉率分别为9.836%和7.580%,嵌合颖花率分别为14.788%和11.810%,黑染花粉率基因型IPCA1数值分别为1.114和0.518,嵌合颖花率基因型IPCA1数值分别为0.133和1.379,表明其不育性较不稳定,花粉育性对播栽温度变化相对敏感。[结论]根据温度对不育系育性影响的变化规律,对于温度敏感型的不育系,宜采取早繁早制的措施,保证种子纯度。在不育系选育和遗传提纯上,应在微效恢复基因高效表达的温度条件下进行,可及早剔除不合格单株或株系,以获得不育性较稳定后代。
