Elite maintainer lines and restorer lines have been developed by genomic DNA transformation,Analyses of molecular markers, DNA sequences, and Southern blotting have revealed that high DNA polymorphism exists between n...Elite maintainer lines and restorer lines have been developed by genomic DNA transformation,Analyses of molecular markers, DNA sequences, and Southern blotting have revealed that high DNA polymorphism exists between new developed lines and its receptors, indicating that the special DNA fragment from distant relatives may be integrated into the genome of rice. And several combinations with the potential of super-high yield have been developed from these lines. Therefore, transformation of genomic DNA from distant relatives to the plant of a target receptor may open an avenue for breeding of super-hybrid rice.展开更多
The concept of lodging resistance core traits and their screening principles were first proposed on the basis of previous research.Afterwards,a lodging resistance breeding method based on phenotypic trait index was pr...The concept of lodging resistance core traits and their screening principles were first proposed on the basis of previous research.Afterwards,a lodging resistance breeding method based on phenotypic trait index was proposed based on a case study of screening lodging resistant aromatic rice by Yuehesimiao and Xiangyaxiangzhan.In other words,the materials that meet the breeding goals could be selected quickly by constructing breeding population and referring to lodging resistance core traits in each generation.Eventually,the advantages and disadvantages of the method were analyzed in combination with the actual situation,in order to provide the reference for rice breeding researchers.展开更多
The green rice leafhopper (GRH;Nephotettix cincticeps Uhler) is one of the most devastating insect pests of cultivated rice (Oryza sativa L.) in temperate regions in Asia. Using the rice germplasms with biotic stress ...The green rice leafhopper (GRH;Nephotettix cincticeps Uhler) is one of the most devastating insect pests of cultivated rice (Oryza sativa L.) in temperate regions in Asia. Using the rice germplasms with biotic stress resistance is the most effective and environmentally-friendly way to control the insect pests in the paddy. Sixty accessions from a core set of worldwide collection of rice were characterized for resistance to the GRH by antibiosis test both at the seedling and at the booting stages. The positive correlations of average nymph mortality (ANM) were observed between at the seedling stage and at the booting stage on 3 days after infestation (DAI) (r = 0.684**), 5DAI (r = 0.680**), and 7DAI (r = 0.652**), respectively. This result will give us the opportunity to screen resistance to the GRH with the cost-efficient way using rice seedlings in a growth chamber. To classify the 60 accessions evaluated, the ANM of the GRH of each accession was compared to the respective ANM of resistant and susceptible controls with the least significant difference (LSD) value. Based on the statistical difference or similarity of the ANMs to the resistant and the susceptible controls, we proposed the four groups of resistance to the GRH, (I) high level of resistance, (II) considerable level of resistance, (III) moderate level of resistance, and (IV) susceptibility. At the seedling stage, a total of 26 accessions were highly resistant in addition to other 6 for considerable level of resistance and other 10 for moderate level of resistance. At the booting stage, on the other hand, a total of 18 accessions were highly resistant in addition to other 3 for considerable level of resistance and other 5 for moderate level of resistance. A total of 42 accessions with high to moderate level of resistance were distributed across 16 countries in Asia in addition to each one for Madagascar and USA. The classification of landraces based on the present protocol for screening resistance to the insect provided fundamental information for genetics and breeding on resistance to the GRH in rice.展开更多
Narrow genetic background is a key limiting factor in breeding stable high-yielding rice. The introduction and utilization of international rice core germplasm is an important way to increase the genetic diversity of ...Narrow genetic background is a key limiting factor in breeding stable high-yielding rice. The introduction and utilization of international rice core germplasm is an important way to increase the genetic diversity of domestic rice varieties. We conducted a genome-wide association study on 5 panicle traits of 315 rice accessions introduced from the international rice micro-core germplasm bank. Based on the tests from Yangzhou of China and Arkansas of American, environment exhibited a significant impacts on panicle length and primary branch number, while grain length, grain width and grain length/width ratio were insensitive to environment changes. We discovered a total of 7, 5, 10, 8 and 6 chromosomal regions or single nucleotide polymorphism marker loci that were significantly associated with primary branch number, panicle length, grain length, grain width and grain length/width ratio, respectively. Among them, eleven regions were associated with grain shape and one region associated with primary branch number, showing the good consistence in two different environments. Significant linear correlation was discovered between the average trait value and the number of favorable alleles carried by the varieties in all associated loci. Among the associated loci, varieties in aromatic and tropical japonica sub-groups possessed most favorable alleles, while those in temperate japonica sub-group contained the least. The domestic varieties mainly harbored unfavorable alleles in six of the associated loci being detected. On the contrary, 15 varieties from 11 different countries harbored more favorable alleles （as many as 30 or more） than the others. Remarkably, all these 15 varieties belonged to the tropical japonica sub-group. In conclusion, our study demonstrates that varieties in the tropical japonica sub-group had high potentials for breeding stable high-yielding rice. Based on this discovery, we proposed a new approach for improving the panicle traits of domestic rice by using tropical japonica varieties.展开更多
以317份贵州香禾糯种质资源为试验材料,10份籼稻材料为对照,采用1 K mGPS SNP芯片对供试材料的遗传多样性和遗传结构进行分析,在此基础上构建贵州香禾糯核心种质并进行评价。结果表明,1 K mGPS SNP芯片在317份香禾糯材料中共获得731个...以317份贵州香禾糯种质资源为试验材料,10份籼稻材料为对照,采用1 K mGPS SNP芯片对供试材料的遗传多样性和遗传结构进行分析,在此基础上构建贵州香禾糯核心种质并进行评价。结果表明,1 K mGPS SNP芯片在317份香禾糯材料中共获得731个良好多态性SNP位点,多态性标记比例为17.89%,最小等位基因频率为0.0505~0.5000,观测杂合度为0~0.6940,期望杂合度为0.0959~0.5000,多态性信息含量为0.0913~0.5736。基于IBS遗传距离的NJ聚类分析将327份水稻材料分为籼、粳两个亚群,其中317份贵州香禾糯划分为粳稻亚群。利用Core Hunter 3对香禾糯原种质设置5%、10%、15%、20%、25%、30%等6种抽样比例,遗传多样性参数的t检验表明,15%的抽样比例即可保持遗传多样性参数的最大化,同时剔除了许多冗余材料,最终确定47份香禾糯资源为构建的核心种质。展开更多
文摘Elite maintainer lines and restorer lines have been developed by genomic DNA transformation,Analyses of molecular markers, DNA sequences, and Southern blotting have revealed that high DNA polymorphism exists between new developed lines and its receptors, indicating that the special DNA fragment from distant relatives may be integrated into the genome of rice. And several combinations with the potential of super-high yield have been developed from these lines. Therefore, transformation of genomic DNA from distant relatives to the plant of a target receptor may open an avenue for breeding of super-hybrid rice.
基金Supported by National Key R&D Program of China (2017YFD0100102)Technical System of Modern Agricultural Industry in Guangdong Province (2019KJ105)+3 种基金Specific Fund of Science and Technology Innovation Strategy (Construction of High-level GDAAS)Major Joint Scientific Research on Good-quality Rice (YCN 2019 No. 73)Key Projects of the President's Fund of GDAAS (201825)Fund of Guangdong Key Laboratory of New Technology in Rice Breeding (2020B1212060047)。
文摘The concept of lodging resistance core traits and their screening principles were first proposed on the basis of previous research.Afterwards,a lodging resistance breeding method based on phenotypic trait index was proposed based on a case study of screening lodging resistant aromatic rice by Yuehesimiao and Xiangyaxiangzhan.In other words,the materials that meet the breeding goals could be selected quickly by constructing breeding population and referring to lodging resistance core traits in each generation.Eventually,the advantages and disadvantages of the method were analyzed in combination with the actual situation,in order to provide the reference for rice breeding researchers.
文摘The green rice leafhopper (GRH;Nephotettix cincticeps Uhler) is one of the most devastating insect pests of cultivated rice (Oryza sativa L.) in temperate regions in Asia. Using the rice germplasms with biotic stress resistance is the most effective and environmentally-friendly way to control the insect pests in the paddy. Sixty accessions from a core set of worldwide collection of rice were characterized for resistance to the GRH by antibiosis test both at the seedling and at the booting stages. The positive correlations of average nymph mortality (ANM) were observed between at the seedling stage and at the booting stage on 3 days after infestation (DAI) (r = 0.684**), 5DAI (r = 0.680**), and 7DAI (r = 0.652**), respectively. This result will give us the opportunity to screen resistance to the GRH with the cost-efficient way using rice seedlings in a growth chamber. To classify the 60 accessions evaluated, the ANM of the GRH of each accession was compared to the respective ANM of resistant and susceptible controls with the least significant difference (LSD) value. Based on the statistical difference or similarity of the ANMs to the resistant and the susceptible controls, we proposed the four groups of resistance to the GRH, (I) high level of resistance, (II) considerable level of resistance, (III) moderate level of resistance, and (IV) susceptibility. At the seedling stage, a total of 26 accessions were highly resistant in addition to other 6 for considerable level of resistance and other 10 for moderate level of resistance. At the booting stage, on the other hand, a total of 18 accessions were highly resistant in addition to other 3 for considerable level of resistance and other 5 for moderate level of resistance. A total of 42 accessions with high to moderate level of resistance were distributed across 16 countries in Asia in addition to each one for Madagascar and USA. The classification of landraces based on the present protocol for screening resistance to the insect provided fundamental information for genetics and breeding on resistance to the GRH in rice.
基金supported by Jiangsu Natural Science Fund, China (Grant No.BK20131224)Agricultural Prospective Fund from Yangzhou, China (Grant No.YZ2014168)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Narrow genetic background is a key limiting factor in breeding stable high-yielding rice. The introduction and utilization of international rice core germplasm is an important way to increase the genetic diversity of domestic rice varieties. We conducted a genome-wide association study on 5 panicle traits of 315 rice accessions introduced from the international rice micro-core germplasm bank. Based on the tests from Yangzhou of China and Arkansas of American, environment exhibited a significant impacts on panicle length and primary branch number, while grain length, grain width and grain length/width ratio were insensitive to environment changes. We discovered a total of 7, 5, 10, 8 and 6 chromosomal regions or single nucleotide polymorphism marker loci that were significantly associated with primary branch number, panicle length, grain length, grain width and grain length/width ratio, respectively. Among them, eleven regions were associated with grain shape and one region associated with primary branch number, showing the good consistence in two different environments. Significant linear correlation was discovered between the average trait value and the number of favorable alleles carried by the varieties in all associated loci. Among the associated loci, varieties in aromatic and tropical japonica sub-groups possessed most favorable alleles, while those in temperate japonica sub-group contained the least. The domestic varieties mainly harbored unfavorable alleles in six of the associated loci being detected. On the contrary, 15 varieties from 11 different countries harbored more favorable alleles （as many as 30 or more） than the others. Remarkably, all these 15 varieties belonged to the tropical japonica sub-group. In conclusion, our study demonstrates that varieties in the tropical japonica sub-group had high potentials for breeding stable high-yielding rice. Based on this discovery, we proposed a new approach for improving the panicle traits of domestic rice by using tropical japonica varieties.
文摘以317份贵州香禾糯种质资源为试验材料,10份籼稻材料为对照,采用1 K mGPS SNP芯片对供试材料的遗传多样性和遗传结构进行分析,在此基础上构建贵州香禾糯核心种质并进行评价。结果表明,1 K mGPS SNP芯片在317份香禾糯材料中共获得731个良好多态性SNP位点,多态性标记比例为17.89%,最小等位基因频率为0.0505~0.5000,观测杂合度为0~0.6940,期望杂合度为0.0959~0.5000,多态性信息含量为0.0913~0.5736。基于IBS遗传距离的NJ聚类分析将327份水稻材料分为籼、粳两个亚群,其中317份贵州香禾糯划分为粳稻亚群。利用Core Hunter 3对香禾糯原种质设置5%、10%、15%、20%、25%、30%等6种抽样比例,遗传多样性参数的t检验表明,15%的抽样比例即可保持遗传多样性参数的最大化,同时剔除了许多冗余材料,最终确定47份香禾糯资源为构建的核心种质。
