Mercury （Hg） is one of the most toxic heavy metals to living organisms and its conspicuous effect is the inhibition of root growth. However, little is known about the molecular genetic basis for root growth under ex...Mercury （Hg） is one of the most toxic heavy metals to living organisms and its conspicuous effect is the inhibition of root growth. However, little is known about the molecular genetic basis for root growth under excess Hg2＋ stress. To map quantitative trait loci （QTLs） in rice for Hg2＋ tolerance, a population of 120 recombinant inbred lines derived from a cross between two japonica cultivars Yuefu and IRAT109 was grown in 0.5 mmol/L CaCI2 solution. Relative root length （RRL）, percentage of the seminal root length in ＋HgCI2 to -HgCI2, was used for assessing Hg2＋ tolerance. In a dose-response experiment, Yuefu had a higher RRL than IRAT109 and showed the most significant difference at the Hg2＋ concentration of 1.5 tJmol/L. Three putative QTLs for RRL were detected on chromosomes 1, 2 and 5, and totally explained about 35.7% of the phenotypic variance in Hg2＋ tolerance. The identified QTLs for RRL might be useful for improving Hg2＋ tolerance of rice by molecular marker-assisted selection.展开更多
Initial flowering date(IFD)is closely related to mature period of peanut pods.In present study,a population of recombinant inbred lines(RIL)derived from the cross between Silihong(female parent)and Jinonghei 3(male pa...Initial flowering date(IFD)is closely related to mature period of peanut pods.In present study,a population of recombinant inbred lines(RIL)derived from the cross between Silihong(female parent)and Jinonghei 3(male parent)was used to map QTLs associated with IFD.The RIL population and its two parental cultivars were planted in two locations of Hebei Province,China from 2015 to 2018(eight environments).Based on a high-density genetic linkage map(including 2996 SNP and 330 SSR markers)previously constructed in our laboratory,QTLs were analyzed using phenotypic data and the best linear unbiased prediction(BLUP)value of initial flowering date by inclusive composite interval mapping(ICIM)method.Interaction effects between every two QTLs and between individual QTL and environment were also analyzed.In cultivated peanut,IFD was affected by genotypic factor and environments simultaneously,and its broad sense heritability(h2)was estimated as 86.8%。Using the IFD phenotypic data from the eight environments,a total of 19 QTLs for IFD were detected,and the phenotypic variation explained(PVE)by each QTL ranged from 1.15 to 21.82%.Especially,five of them were also detected by the BLUP value of IFD.In addition,12 additive QTLs and 35 pairs of epistatic QTLs(62 loci involved)were identifed by the joint analysis of IFD across eight environments.Three QTLs(qIFDB04.1,qIFDB07.1 and qIFDB08.1)located on chromosome B04,B07 and B08 were identified as main-effect QTL for IFD,which had the most potential to be used in peanut breeding.This study would be helpful for the early-maturity and adaptability breeding in cultivated peanut.展开更多
Heading date is a crucial agronomic trait.However,rice usually delays heading due to the photoperiod,temperature,hormones or age.The present research was conducted to analyze the mechanism cotrlling heading date in F,...Heading date is a crucial agronomic trait.However,rice usually delays heading due to the photoperiod,temperature,hormones or age.The present research was conducted to analyze the mechanism cotrlling heading date in F,hybrid rice.We constructed two test-crossing populations using two introgression lines(ILs),P20 and P21 coming from SH527/FH838 as the male parent,respectively,and male sterile line Jin23A as the female parent.Meanwhile,the F,hybrids of H20,obtained by mating P20 with Jin23A and having no heading,and H21,from the crossing between P21 and Jin23A having normal heading,were both observed under long days.Here,we analyzed the photoperiodic response of F,hybrids by transcriptome and metabolome profiling.The greater differences displayed in the transcriptome and the metabolome were caused by photoperiod(exogenous)instead of genes(endogenous).The coping mechanism resulted from long days(LD)in H20,leading to differences in the circadian rhythm and glutathione metabolism relative to other samples.The circadian oscillator and GSH/GSSG cycle typically regulate ROS homeostasis,and both of them are responsible for modulating ROS in H20 under LD condition.Both circadian rhythm genes and the reported genes related to heading date function via the DHD1/OsMFT1-Ehd1-RFT1-OsMADS14/OsMADS18 pathway and the glutathione metabolism pathway by regulating oxidative reduction processes.Both pathways are involved in the heading process and they interacted through the oxidative reduction process which was induced by photoperiod regulation,and all of them collectively modulated the heading process.The results of this study will be helpful for unraveling the mechanism of F,hybrid responses to unheading under LD condition.展开更多
The QTL qTGW3-1 was located on chromosome 3 of rice （Oryza sativa L.） and associated with the 1 000-grain weight （TGW） according to the result of our earlier study. With the objective of fine mapping of this locus...The QTL qTGW3-1 was located on chromosome 3 of rice （Oryza sativa L.） and associated with the 1 000-grain weight （TGW） according to the result of our earlier study. With the objective of fine mapping of this locus, we developed a F2 population consisting of 3 428 plants derived from the cross between TGW-related near isogenic line DL017 （BC3F4 generation of GSL 156×Nipponbare） and the recurrent parent Nipponbare. Using six microsatellites, this QTL was delimited between RM5477 and RM6417. Markers MM 1455 and MM 1456 within this region were used for further mapping of this QTL. Finally, qTGW3-1 was fine-mapped into a 89-kb interval between RM5477 and MM1456, which locates in the BAC clone AC107226 harboring five putative candidate genes.展开更多
The lower seed setting is one of the major hindrances which face grain yield in rice. One of the main reasons to cause low spikelet fertility （seed setting） is male sterility or pollen abortion. Notably, pollen abor...The lower seed setting is one of the major hindrances which face grain yield in rice. One of the main reasons to cause low spikelet fertility （seed setting） is male sterility or pollen abortion. Notably, pollen abortion has been frequently observed in advanced progenies of rice. In the present study, 149 BC2F6 individuals with significant segregation in spikelet fertility were generated from the cross between N040212 （indica） and Nipponbare （japonica） and used for primary gene mapping. Three QTLs, qSS-1, qSS-7 and qSS-9 at chromosomes 1, 7 and 9, respectively, were found to be associated with seed setting. The recombinant analysis and the physical mapping information from publicly available resources exhibited that the qSS-1, qSS-7 and qSS-9 loci were mapped to an interval of 188, 701 and 3741 kb, respectively. The seed setting responsible for QTL qSS-1 was further fine mapped to 93.5 kb by using BC2F7 population of 1 849 individuals. There are 16 possible putative genes in this 93.5 kb region. Pollen vitality tests and artificial pollination indicated that the male gamete has abnormal pollen while the female gamete was normal. These data showed that low seed setting rate relative to qSS-1 may be caused by abnormal pollen grains. These results will be useful for cloning, functional analysis of the target gene governing spikelet fertility （seed setting） and understanding the genetic bases of pollen sterility.展开更多
基金funded by the National Natural Science Foundation of China(Grant No.30771330)the National Natural Science Foundation of Zhejiang Province,China(Grant No.Z306300)the Zhejiang Normal University Innovative Research Team Program of China
文摘Mercury （Hg） is one of the most toxic heavy metals to living organisms and its conspicuous effect is the inhibition of root growth. However, little is known about the molecular genetic basis for root growth under excess Hg2＋ stress. To map quantitative trait loci （QTLs） in rice for Hg2＋ tolerance, a population of 120 recombinant inbred lines derived from a cross between two japonica cultivars Yuefu and IRAT109 was grown in 0.5 mmol/L CaCI2 solution. Relative root length （RRL）, percentage of the seminal root length in ＋HgCI2 to -HgCI2, was used for assessing Hg2＋ tolerance. In a dose-response experiment, Yuefu had a higher RRL than IRAT109 and showed the most significant difference at the Hg2＋ concentration of 1.5 tJmol/L. Three putative QTLs for RRL were detected on chromosomes 1, 2 and 5, and totally explained about 35.7% of the phenotypic variance in Hg2＋ tolerance. The identified QTLs for RRL might be useful for improving Hg2＋ tolerance of rice by molecular marker-assisted selection.
基金Supported by the earmarked fund for China Agriculture Research System(CARS-13)the National Natural Science Foundatlon of China(31771833)+1 种基金the Science and Technology Supporting Plan Project of Hebei Province,China(16226301D)the Key Projects of Science and Technology Research in Higher Education Institution of Hebei Province,China(ZD2015056).
文摘Initial flowering date(IFD)is closely related to mature period of peanut pods.In present study,a population of recombinant inbred lines(RIL)derived from the cross between Silihong(female parent)and Jinonghei 3(male parent)was used to map QTLs associated with IFD.The RIL population and its two parental cultivars were planted in two locations of Hebei Province,China from 2015 to 2018(eight environments).Based on a high-density genetic linkage map(including 2996 SNP and 330 SSR markers)previously constructed in our laboratory,QTLs were analyzed using phenotypic data and the best linear unbiased prediction(BLUP)value of initial flowering date by inclusive composite interval mapping(ICIM)method.Interaction effects between every two QTLs and between individual QTL and environment were also analyzed.In cultivated peanut,IFD was affected by genotypic factor and environments simultaneously,and its broad sense heritability(h2)was estimated as 86.8%。Using the IFD phenotypic data from the eight environments,a total of 19 QTLs for IFD were detected,and the phenotypic variation explained(PVE)by each QTL ranged from 1.15 to 21.82%.Especially,five of them were also detected by the BLUP value of IFD.In addition,12 additive QTLs and 35 pairs of epistatic QTLs(62 loci involved)were identifed by the joint analysis of IFD across eight environments.Three QTLs(qIFDB04.1,qIFDB07.1 and qIFDB08.1)located on chromosome B04,B07 and B08 were identified as main-effect QTL for IFD,which had the most potential to be used in peanut breeding.This study would be helpful for the early-maturity and adaptability breeding in cultivated peanut.
基金Supported by the National Basic Research Program of China(2014AA10A604).
文摘Heading date is a crucial agronomic trait.However,rice usually delays heading due to the photoperiod,temperature,hormones or age.The present research was conducted to analyze the mechanism cotrlling heading date in F,hybrid rice.We constructed two test-crossing populations using two introgression lines(ILs),P20 and P21 coming from SH527/FH838 as the male parent,respectively,and male sterile line Jin23A as the female parent.Meanwhile,the F,hybrids of H20,obtained by mating P20 with Jin23A and having no heading,and H21,from the crossing between P21 and Jin23A having normal heading,were both observed under long days.Here,we analyzed the photoperiodic response of F,hybrids by transcriptome and metabolome profiling.The greater differences displayed in the transcriptome and the metabolome were caused by photoperiod(exogenous)instead of genes(endogenous).The coping mechanism resulted from long days(LD)in H20,leading to differences in the circadian rhythm and glutathione metabolism relative to other samples.The circadian oscillator and GSH/GSSG cycle typically regulate ROS homeostasis,and both of them are responsible for modulating ROS in H20 under LD condition.Both circadian rhythm genes and the reported genes related to heading date function via the DHD1/OsMFT1-Ehd1-RFT1-OsMADS14/OsMADS18 pathway and the glutathione metabolism pathway by regulating oxidative reduction processes.Both pathways are involved in the heading process and they interacted through the oxidative reduction process which was induced by photoperiod regulation,and all of them collectively modulated the heading process.The results of this study will be helpful for unraveling the mechanism of F,hybrid responses to unheading under LD condition.
基金supported by the National Basic Research Program of China (2010CB129504)the National Key Technologies R&D Program of China (2009BADA2B01)the 948 Project of MOA, China (2011-G2B)
文摘The QTL qTGW3-1 was located on chromosome 3 of rice （Oryza sativa L.） and associated with the 1 000-grain weight （TGW） according to the result of our earlier study. With the objective of fine mapping of this locus, we developed a F2 population consisting of 3 428 plants derived from the cross between TGW-related near isogenic line DL017 （BC3F4 generation of GSL 156×Nipponbare） and the recurrent parent Nipponbare. Using six microsatellites, this QTL was delimited between RM5477 and RM6417. Markers MM 1455 and MM 1456 within this region were used for further mapping of this QTL. Finally, qTGW3-1 was fine-mapped into a 89-kb interval between RM5477 and MM1456, which locates in the BAC clone AC107226 harboring five putative candidate genes.
基金supported by the National Key Technologies R&D Program of China during the 12th Five-Year Plan period (2013BAD01B02-15 and 2015BAD02B01)the 948 Project of Minstry of Agriculture, China (2011-G2B and 2011-G1 (2)-25)
文摘The lower seed setting is one of the major hindrances which face grain yield in rice. One of the main reasons to cause low spikelet fertility （seed setting） is male sterility or pollen abortion. Notably, pollen abortion has been frequently observed in advanced progenies of rice. In the present study, 149 BC2F6 individuals with significant segregation in spikelet fertility were generated from the cross between N040212 （indica） and Nipponbare （japonica） and used for primary gene mapping. Three QTLs, qSS-1, qSS-7 and qSS-9 at chromosomes 1, 7 and 9, respectively, were found to be associated with seed setting. The recombinant analysis and the physical mapping information from publicly available resources exhibited that the qSS-1, qSS-7 and qSS-9 loci were mapped to an interval of 188, 701 and 3741 kb, respectively. The seed setting responsible for QTL qSS-1 was further fine mapped to 93.5 kb by using BC2F7 population of 1 849 individuals. There are 16 possible putative genes in this 93.5 kb region. Pollen vitality tests and artificial pollination indicated that the male gamete has abnormal pollen while the female gamete was normal. These data showed that low seed setting rate relative to qSS-1 may be caused by abnormal pollen grains. These results will be useful for cloning, functional analysis of the target gene governing spikelet fertility （seed setting） and understanding the genetic bases of pollen sterility.
