A mutant was isolated from the M2 of 60Co-γ ray mutagenized male-fertility restorer line Zao-R974 in rice. The mutant showed pleiotropic phenotypes including dwarfism, delayed heading time, short and partially enclos...A mutant was isolated from the M2 of 60Co-γ ray mutagenized male-fertility restorer line Zao-R974 in rice. The mutant showed pleiotropic phenotypes including dwarfism, delayed heading time, short and partially enclosed panicles, short uppermost internode, decreased grain and secondary branch numbers per panicle, and partially degenerated spikelets. The mutant was named as esp1 (enclosed shorter panicle 1). Genetic analysis indicated that the mutant phenotype was controlled by a recessive locus. Spraying exogenous GA3 did not rescue the panicle enclosure. Using an F2 and a BC1 population of the cross between esp1 and a japonica cultivar Nipponbare, we mapped the ESP1 locus to a region of ～260 kb on chromosome 11. This result provides a basis for further map-based cloning of the ESP1 locus.展开更多
As a specific type of acid phosphatses, phytases play diverse roles in plants by catalazing the degradation of phytic acid and its derivatives. In this study, a rice phytase gene referred to OsPHY1 has been functional...As a specific type of acid phosphatses, phytases play diverse roles in plants by catalazing the degradation of phytic acid and its derivatives. In this study, a rice phytase gene referred to OsPHY1 has been functionally characterized. OsPHY1 contains a 1 620 bp of open reading frame, encoding a 539-aa polypeptide. A conserve domain metallophosphatase (MPP) (MPP_PAPs), generally harbored in phytase and purple acid phosphatases (PAP), was identified in OsPHY1 (residue 194-398). Phylogenetic analysis revealed that OsPHY1 shares high similarities with phytase genes and PAP-type genes that derived from diverse plant species. The OsPHY1 transcripts were detected to be abundant in germinating seeds, suggesting that this gene plays potential roles on degradation of seed phytic acid and its derivatives during the germination process. Biochemical analysis confirmed that OsPHY1 possesses strong catalytic activities on phytic acid-Na2, with optimal temperature of 57°C and suitable pH of 3.5. Based on transgene analysis, the putative role of OsPHY1 in plants on utilization of phytate was assessed. Under the condition that phytic acid-Na2 was used as sole P source, the OsPHY1-overexpressing tobacco plants behaved higher phytase activities, higher concentrations of Pi, more accumulative amount of total phosphorus, and much more improved growth traits than those of the control plants. Therefore, OsPHY1 is acted as an important component on degradation of the phytins during the seed germination process in rice. Also, OsPHY1 has a potential use on generation of elite crop germplasms with improved use efficiencies on phytate and its derivatives.展开更多
312 recombinant inbred lines(RILs) in F 9 from a cross between a overwintering cold-tolerant germplasm resource Glutinous rice 89-1(Gr 89-1) and a cold-sensitive variety Shuhui 527 was used for quantitative trait locu...312 recombinant inbred lines(RILs) in F 9 from a cross between a overwintering cold-tolerant germplasm resource Glutinous rice 89-1(Gr 89-1) and a cold-sensitive variety Shuhui 527 was used for quantitative trait locus(QTL) analysis.The scores of percent ratooning germinability(PRG) and overwintering germinability(POG) were evaluated.The overwintering germination rate of axillary buds was scored to represent the overwintering germinability.Two significant QTLs(qPRG-4 and qPRG-7) on chromosomes 4 and 7 were detected and explained 8.3 and 7.2% of the total phenotypic variation,respectively.Three significant QTLs(qPOG-2,qPOG-3 and qPOG-7) were identified and mapped on chromosomes 2,3,and 7,respectively.These QTLs contributed 9.6,6.7,and 17.8% of phenotypic variations,respectively.A comparative analysis using SSR markers closely linked to the three QTLs for the overwintering revealed cold-tolerant individuals,which harbour the Glutinous rice 89-1 alleles at RM7110,RM250,RM418,and RM232,had a high percent overwintering germinability,while cold-sensitive individuals,which carry Shuhui 527 alleles at these loci,had a low percent overwintering germinability in the F 2 population of Shuhui 527/Glutinous rice 89-1.This study demonstrated the utility of these SSR markers for selection of overwintering germinability genotypes.展开更多
High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice (Oryza sativa L.) in China. We previously showed a major quantitative trait locus for the percentage of grains wi...High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice (Oryza sativa L.) in China. We previously showed a major quantitative trait locus for the percentage of grains with white chalkiness (QTLqPGWC-8) in the interval G1149-R727 on chromosome 8 using a chromosome segment substitution line (CSSL). Here, we selected the line-CSSL50 harboring the QTLqPGWC-8 allele from the CSSLs derived from a cross between Asominori (as a recurrent parent) and IR24 (as a donor parent), which had higher percentage chalkiness, markedly different from that of Asominori. There were also significant differences in starch granules, appearance of amylose content (AAC) and milling qualities between Asominori and CSSL50, but not in grain size or thousand grain weight (TGW). The BC4F2 and BC4F3 populations from a cross between CSSL50 and Asominori were used for fine mapping of qPGWC-8. We narrowed down the location of this QTL to a 142 kb region between Indel markers 8G-7 and 8G-9. QTLqPGWC-8 accounted for 50.9% of the difference in PGWC between the parents. The markers tightly linked to qPGWC-8 should facilitate cloning of the gene underlying this QTL and will be of value for marker-assisted selection in breeding rice varieties with better grain quality.展开更多
Silicon (Si) can enhance the resistance of plants to many abiotic stresses. To explore whether Si ameliorates Fe2+ toxicity, a hydroponic experiment was performed to investigate whether and how Si detoxifies Fe2+ toxi...Silicon (Si) can enhance the resistance of plants to many abiotic stresses. To explore whether Si ameliorates Fe2+ toxicity, a hydroponic experiment was performed to investigate whether and how Si detoxifies Fe2+ toxicity in rice (Oryza sativa L.) roots. Results indicated that rice cultivar Tianyou 998 (TY998) showed greater sensitivity to Fe2+ toxicity than rice cultivar Peizataifeng (PZTF). Treatment with 0.1 mmol L-1 Fe2+ inhibited TY998 root elongation and root biomass significantly. Reddish iron plaque was formed on root surface of both cultivars. TY998 had a higher amount of iron plaque than PZTF. Addition of Si to the solution of Fe treatment decreased the amount of iron plaque on root surface by 17.6% to 37.1% and iron uptake in rice roots by 37.0% to 40.3%, and subsequently restored root elongation triggered by Fe2+ toxicity by 13.5% in the TY998. Compared with Fe treatment, the addition of 1 mmol L-1 Si to the solution of Fe treatment increased xylem sap flow by 19.3% to 24.8% and root-shoot Fe transportation by 45.0% to 78.6%. Furthermore, Si addition to the solution of Fe treatment induced root cell wall to thicken. These results suggested that Si could detoxify Fe2+ toxicity and Si-mediated amelioration of Fe2+ toxicity in rice roots was associated with less iron plaque on root surface and more Fe transportation from roots to shoots.展开更多
The leaf blade consists of color and shape traits.Studies of leaf-blade development are important for improvement of rice yield and quality because it is an essential organ for photosynthesis.A narrow and upper-albino...The leaf blade consists of color and shape traits.Studies of leaf-blade development are important for improvement of rice yield and quality because it is an essential organ for photosynthesis.A narrow and upper-albino leaf mutant(nul1) was identified from among progeny of the indica restorer line Jinhui10 raised from seeds treated with ethyl methane sulfonate.Under field conditions,the mutant displayed narrow and upper-albino leaf blades with significantly decreased photosynthetic pigment contents throughout their development.The narrow-leaf trait is caused by a decreased number of small veins.In contrast to the wild type,the growth period was extended by approximately 8 d and agronomic traits,such as effective panicle number,percentage seed set and 1000-grain weight,declined significantly in the nul1 mutant.Genetic analysis suggested that the narrow and upper-albino leaf characteristics showed coseparation and were controlled by one recessive gene.The Nul1 gene was mapped onto chromosome 7 between the Indel marker Ind07-1 and the Simple Sequence Repeat marker RM21637.The physical distance between the markers was 75 kb and eight genes were annotated in this region based on the rice Nipponbare genome sequence.These results provide a foundation for cloning and function analysis of Nul1.展开更多
The shape and color of rice leaves are important agronomic traits that directly influence the proportion of sunlight energy utilization and ultimately affect the yield and quality.A new mutant exhibiting stable inheri...The shape and color of rice leaves are important agronomic traits that directly influence the proportion of sunlight energy utilization and ultimately affect the yield and quality.A new mutant exhibiting stable inheritance was identified as derived from ethyl methane sulfonate(EMS)-treated restorer Jinhui 10,tentatively named as narrow and striped leaf 1(nsl1).The nsl1 displayed pale white leaves at the seeding stage and then white striped leaves in parallel to the main vein at the jointing stage.Meanwhile,its leaf blades are significantly narrower than the control group of Jinhui 10.The chloroplast structures of cells in the white striped area of the nsl1 mutant break down,and the photosynthetic pigments are significantly lower than that of the wild type.Moreover,fluorescence parameters,such as F0,F v/F m,U psII,qp,and ETR,in the nsl1 mutant are significantly lower than those of the wild type,and the photosynthetic efficiency is also significantly decreased.These changes in leaf color and shape,together with physiological changes in the nsl1,result in smaller plant height and a decrease in the most important agronomic traits,such as the number of grains per panicle,grain weight,etc.Genetic analysis shows that the narrow and striped traits of the nsl1 mutant are controlled by a single recessive nuclear gene,which is located between InDel 16and InDel 12 in chromosome 3.The physical distance is204 kb.So far,no similar genes of such leaf color and shape in this area have been reported.This study has laid a solid foundation for the gene cloning and function analysis of NSL1.展开更多
基金supported by the National Transgenic Projects of China(2009ZX-08009-109B)the Natural Science Foundation of Fujian Province, China(2012J01091)the New Century Excellent Talents in University of Fujian Province, China(KY0010057)
文摘A mutant was isolated from the M2 of 60Co-γ ray mutagenized male-fertility restorer line Zao-R974 in rice. The mutant showed pleiotropic phenotypes including dwarfism, delayed heading time, short and partially enclosed panicles, short uppermost internode, decreased grain and secondary branch numbers per panicle, and partially degenerated spikelets. The mutant was named as esp1 (enclosed shorter panicle 1). Genetic analysis indicated that the mutant phenotype was controlled by a recessive locus. Spraying exogenous GA3 did not rescue the panicle enclosure. Using an F2 and a BC1 population of the cross between esp1 and a japonica cultivar Nipponbare, we mapped the ESP1 locus to a region of ～260 kb on chromosome 11. This result provides a basis for further map-based cloning of the ESP1 locus.
基金supported by the National Natural Science Foundation of China (30871466)and the Key Laboratory of Crop Growth Regulation of Hebei Province, China
文摘As a specific type of acid phosphatses, phytases play diverse roles in plants by catalazing the degradation of phytic acid and its derivatives. In this study, a rice phytase gene referred to OsPHY1 has been functionally characterized. OsPHY1 contains a 1 620 bp of open reading frame, encoding a 539-aa polypeptide. A conserve domain metallophosphatase (MPP) (MPP_PAPs), generally harbored in phytase and purple acid phosphatases (PAP), was identified in OsPHY1 (residue 194-398). Phylogenetic analysis revealed that OsPHY1 shares high similarities with phytase genes and PAP-type genes that derived from diverse plant species. The OsPHY1 transcripts were detected to be abundant in germinating seeds, suggesting that this gene plays potential roles on degradation of seed phytic acid and its derivatives during the germination process. Biochemical analysis confirmed that OsPHY1 possesses strong catalytic activities on phytic acid-Na2, with optimal temperature of 57°C and suitable pH of 3.5. Based on transgene analysis, the putative role of OsPHY1 in plants on utilization of phytate was assessed. Under the condition that phytic acid-Na2 was used as sole P source, the OsPHY1-overexpressing tobacco plants behaved higher phytase activities, higher concentrations of Pi, more accumulative amount of total phosphorus, and much more improved growth traits than those of the control plants. Therefore, OsPHY1 is acted as an important component on degradation of the phytins during the seed germination process in rice. Also, OsPHY1 has a potential use on generation of elite crop germplasms with improved use efficiencies on phytate and its derivatives.
基金supported by the Rice Key Project of Chongqing,China (CSTC2011AB1076)the Foundation Project of Chongqing Education Commission (KJ110623)+1 种基金the Doctor Foundation of Chongqing Normal University,China (10LR028)the Plants Breeding Project of Chongqing,China (CSTC2010AA1033)
文摘312 recombinant inbred lines(RILs) in F 9 from a cross between a overwintering cold-tolerant germplasm resource Glutinous rice 89-1(Gr 89-1) and a cold-sensitive variety Shuhui 527 was used for quantitative trait locus(QTL) analysis.The scores of percent ratooning germinability(PRG) and overwintering germinability(POG) were evaluated.The overwintering germination rate of axillary buds was scored to represent the overwintering germinability.Two significant QTLs(qPRG-4 and qPRG-7) on chromosomes 4 and 7 were detected and explained 8.3 and 7.2% of the total phenotypic variation,respectively.Three significant QTLs(qPOG-2,qPOG-3 and qPOG-7) were identified and mapped on chromosomes 2,3,and 7,respectively.These QTLs contributed 9.6,6.7,and 17.8% of phenotypic variations,respectively.A comparative analysis using SSR markers closely linked to the three QTLs for the overwintering revealed cold-tolerant individuals,which harbour the Glutinous rice 89-1 alleles at RM7110,RM250,RM418,and RM232,had a high percent overwintering germinability,while cold-sensitive individuals,which carry Shuhui 527 alleles at these loci,had a low percent overwintering germinability in the F 2 population of Shuhui 527/Glutinous rice 89-1.This study demonstrated the utility of these SSR markers for selection of overwintering germinability genotypes.
基金supported by the National Natural Science Foundation of China(30771325)National Key Transform Program(2008ZX08001-06)+2 种基金the earmarked fund for Modern Agro-industry Technology Research SystemJiangsu Cultivar Development Program(BE2008354 and BE2009301-3)the 111 project
文摘High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice (Oryza sativa L.) in China. We previously showed a major quantitative trait locus for the percentage of grains with white chalkiness (QTLqPGWC-8) in the interval G1149-R727 on chromosome 8 using a chromosome segment substitution line (CSSL). Here, we selected the line-CSSL50 harboring the QTLqPGWC-8 allele from the CSSLs derived from a cross between Asominori (as a recurrent parent) and IR24 (as a donor parent), which had higher percentage chalkiness, markedly different from that of Asominori. There were also significant differences in starch granules, appearance of amylose content (AAC) and milling qualities between Asominori and CSSL50, but not in grain size or thousand grain weight (TGW). The BC4F2 and BC4F3 populations from a cross between CSSL50 and Asominori were used for fine mapping of qPGWC-8. We narrowed down the location of this QTL to a 142 kb region between Indel markers 8G-7 and 8G-9. QTLqPGWC-8 accounted for 50.9% of the difference in PGWC between the parents. The markers tightly linked to qPGWC-8 should facilitate cloning of the gene underlying this QTL and will be of value for marker-assisted selection in breeding rice varieties with better grain quality.
基金Supported by the National Natural Science Foundation of China (Nos. 31071847 and 31172026)the Ph.D. Programs Foundation of Ministry of Education of China (No. 20104404110016)the Foundation for High-level Talents in Higher Education of Guangdong, China
文摘Silicon (Si) can enhance the resistance of plants to many abiotic stresses. To explore whether Si ameliorates Fe2+ toxicity, a hydroponic experiment was performed to investigate whether and how Si detoxifies Fe2+ toxicity in rice (Oryza sativa L.) roots. Results indicated that rice cultivar Tianyou 998 (TY998) showed greater sensitivity to Fe2+ toxicity than rice cultivar Peizataifeng (PZTF). Treatment with 0.1 mmol L-1 Fe2+ inhibited TY998 root elongation and root biomass significantly. Reddish iron plaque was formed on root surface of both cultivars. TY998 had a higher amount of iron plaque than PZTF. Addition of Si to the solution of Fe treatment decreased the amount of iron plaque on root surface by 17.6% to 37.1% and iron uptake in rice roots by 37.0% to 40.3%, and subsequently restored root elongation triggered by Fe2+ toxicity by 13.5% in the TY998. Compared with Fe treatment, the addition of 1 mmol L-1 Si to the solution of Fe treatment increased xylem sap flow by 19.3% to 24.8% and root-shoot Fe transportation by 45.0% to 78.6%. Furthermore, Si addition to the solution of Fe treatment induced root cell wall to thicken. These results suggested that Si could detoxify Fe2+ toxicity and Si-mediated amelioration of Fe2+ toxicity in rice roots was associated with less iron plaque on root surface and more Fe transportation from roots to shoots.
基金supported by the National Natural Science Foundation of China (31171178)the Fundamental Research Funds for the Central Universities (XDJK2009B019)
文摘The leaf blade consists of color and shape traits.Studies of leaf-blade development are important for improvement of rice yield and quality because it is an essential organ for photosynthesis.A narrow and upper-albino leaf mutant(nul1) was identified from among progeny of the indica restorer line Jinhui10 raised from seeds treated with ethyl methane sulfonate.Under field conditions,the mutant displayed narrow and upper-albino leaf blades with significantly decreased photosynthetic pigment contents throughout their development.The narrow-leaf trait is caused by a decreased number of small veins.In contrast to the wild type,the growth period was extended by approximately 8 d and agronomic traits,such as effective panicle number,percentage seed set and 1000-grain weight,declined significantly in the nul1 mutant.Genetic analysis suggested that the narrow and upper-albino leaf characteristics showed coseparation and were controlled by one recessive gene.The Nul1 gene was mapped onto chromosome 7 between the Indel marker Ind07-1 and the Simple Sequence Repeat marker RM21637.The physical distance between the markers was 75 kb and eight genes were annotated in this region based on the rice Nipponbare genome sequence.These results provide a foundation for cloning and function analysis of Nul1.
基金supported by Key Scientific Programs of Chongqing City(CSTC2012ggC 80002)
文摘The shape and color of rice leaves are important agronomic traits that directly influence the proportion of sunlight energy utilization and ultimately affect the yield and quality.A new mutant exhibiting stable inheritance was identified as derived from ethyl methane sulfonate(EMS)-treated restorer Jinhui 10,tentatively named as narrow and striped leaf 1(nsl1).The nsl1 displayed pale white leaves at the seeding stage and then white striped leaves in parallel to the main vein at the jointing stage.Meanwhile,its leaf blades are significantly narrower than the control group of Jinhui 10.The chloroplast structures of cells in the white striped area of the nsl1 mutant break down,and the photosynthetic pigments are significantly lower than that of the wild type.Moreover,fluorescence parameters,such as F0,F v/F m,U psII,qp,and ETR,in the nsl1 mutant are significantly lower than those of the wild type,and the photosynthetic efficiency is also significantly decreased.These changes in leaf color and shape,together with physiological changes in the nsl1,result in smaller plant height and a decrease in the most important agronomic traits,such as the number of grains per panicle,grain weight,etc.Genetic analysis shows that the narrow and striped traits of the nsl1 mutant are controlled by a single recessive nuclear gene,which is located between InDel 16and InDel 12 in chromosome 3.The physical distance is204 kb.So far,no similar genes of such leaf color and shape in this area have been reported.This study has laid a solid foundation for the gene cloning and function analysis of NSL1.
