Iron and zinc are two trace elements that are essential for rice. But they are toxic at higher concentrations, leading to severe rice yield losses especially in acid soils and inland valleys. In this study, two recipr...Iron and zinc are two trace elements that are essential for rice. But they are toxic at higher concentrations, leading to severe rice yield losses especially in acid soils and inland valleys. In this study, two reciprocal introgression line(IL) populations sharing the same parents were used with high-density SNP bin markers to identify QTL tolerant to iron and zinc toxicities. The results indicated that the japonica variety 02,428 had stronger tolerance to iron and zinc toxicities than the indica variety Minghui 63. Nine and ten QTL contributing to iron and zinc toxicity tolerances,respectively, were identified in the two IL populations. The favorable alleles of most QTL came from 02,428. Among them, q FRRDW2, q ZRRDW3, and q FRSDW11 appeared to be independent of genetic background. The region C11S49–C11S60 on chromosome 11 harbored QTL affecting multiple iron and zinc toxicity tolerance-related traits, indicating partial genetic overlap between the two toxicity tolerances. Our results provide essential information and materials for developing excellent rice cultivars with iron and/or zinc tolerance by marker-assisted selection(MAS).展开更多
The fungus Magnaporthe oryzae threatens the rice production of Kongyu 131 (KY131),a leading japonica variety in Northeast China.In this study,two rice lines,KP1 and KP2-Hd1,were obtained by introgressing the blast res...The fungus Magnaporthe oryzae threatens the rice production of Kongyu 131 (KY131),a leading japonica variety in Northeast China.In this study,two rice lines,KP1 and KP2-Hd1,were obtained by introgressing the blast resistance genes Pi1 and Pi2 into KY131,respectively.However,both lines headed later than KY131.RICE60K SNP array analysis showed that Hd1 closely linked to Pi2 was introgressed into KP2-Hd1,and the linkage drag of Hd1 was broken by recombination.On the other hand,no known flowering genes were introgressed into KP1.Gene diagnosis by resequencing six flowering genes showed that KP1 carried functional Hd16 and Ghd8 alleles.Due to its suppression role in heading under long-day conditions,Ghd8 was chosen as the target for gene editing to disrupt its function.Four sgRNAs targeting different sites within Ghd8 were utilized to induce large-deletion mutations,which were easy to detect via agarose gel electrophoresis.All the ghd8-mutated KP1 lines were resistant to rice blast disease and headed earlier than the control KP1,even than KY131,under natural long-day conditions,which ensures its growth in Northeast China.This study confirmed that a combination of gene diagnosis and targeted gene editing is a highly efficient way to quickly eliminate undesired traits in a breeding line.展开更多
基金funded by the National High Technology Research and Development Program of China (No. 2014AA10A601)Hubei Collaborative Innovation Center for Grain Industry (No.LXT-16-01) to JLX+2 种基金the Shenzhen Peacock Plan (No.20130415095710361) to ZKLthe CAAS Innovative Team Award to JLX's teamKey Discipline of Crop Science of Yangtze University to HL
文摘Iron and zinc are two trace elements that are essential for rice. But they are toxic at higher concentrations, leading to severe rice yield losses especially in acid soils and inland valleys. In this study, two reciprocal introgression line(IL) populations sharing the same parents were used with high-density SNP bin markers to identify QTL tolerant to iron and zinc toxicities. The results indicated that the japonica variety 02,428 had stronger tolerance to iron and zinc toxicities than the indica variety Minghui 63. Nine and ten QTL contributing to iron and zinc toxicity tolerances,respectively, were identified in the two IL populations. The favorable alleles of most QTL came from 02,428. Among them, q FRRDW2, q ZRRDW3, and q FRSDW11 appeared to be independent of genetic background. The region C11S49–C11S60 on chromosome 11 harbored QTL affecting multiple iron and zinc toxicity tolerance-related traits, indicating partial genetic overlap between the two toxicity tolerances. Our results provide essential information and materials for developing excellent rice cultivars with iron and/or zinc tolerance by marker-assisted selection(MAS).
基金supported by grants from the National Special Program for Research of Transgenic Plant of China(2011ZX08009-001002)the National Key Research and Development Program of China(2016YFD0100301)
文摘The fungus Magnaporthe oryzae threatens the rice production of Kongyu 131 (KY131),a leading japonica variety in Northeast China.In this study,two rice lines,KP1 and KP2-Hd1,were obtained by introgressing the blast resistance genes Pi1 and Pi2 into KY131,respectively.However,both lines headed later than KY131.RICE60K SNP array analysis showed that Hd1 closely linked to Pi2 was introgressed into KP2-Hd1,and the linkage drag of Hd1 was broken by recombination.On the other hand,no known flowering genes were introgressed into KP1.Gene diagnosis by resequencing six flowering genes showed that KP1 carried functional Hd16 and Ghd8 alleles.Due to its suppression role in heading under long-day conditions,Ghd8 was chosen as the target for gene editing to disrupt its function.Four sgRNAs targeting different sites within Ghd8 were utilized to induce large-deletion mutations,which were easy to detect via agarose gel electrophoresis.All the ghd8-mutated KP1 lines were resistant to rice blast disease and headed earlier than the control KP1,even than KY131,under natural long-day conditions,which ensures its growth in Northeast China.This study confirmed that a combination of gene diagnosis and targeted gene editing is a highly efficient way to quickly eliminate undesired traits in a breeding line.
