Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide...Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide fludioxonil is a key agent for FCR control.Previous studies indicated that resistance to fludioxonil in F.pseudograminearum is primarily associated with altered expression levels of the FpOS1 gene,which encodes a hybrid histidine kinase.However,the roles of mutations in other FpOS genes and the molecular interactions between FpOS proteins and fludioxonil remain elusive.To address these gaps,we generated 16 fludioxonil-resistant mutants with heritable resistance traits by in vitro selection of four sensitive F.pseudograminearum isolates.These mutants exhibited high resistance levels,with resistance factors(RF)ranging from 633.73 to 8617.07.Compared to their parental isolates,the resistant mutants showed significantly reduced mycelial growth rate,sporulation capacity,and pathogenicity.They were also more sensitive to ionic,osmotic,and oxidative stresses and displayed compromised cell wall and membrane integrity.Fludioxonil demonstrated no cross-resistance with tebuconazole or pydiflumetofen;however,it exhibited weak positive crossresistance to pyraclostrobin and moderate positive cross-resistance to iprodione.Fludioxonil treatment significantly promoted glycerol synthesis and inhibited deoxynivalenol(DON)production in parental isolates,whereas these regulatory effects were markedly attenuated in the resistant mutants.Mutation analysis identified mutation sites in FpOS1,FpOS4,and FpOS5 genes,with a lower mutation frequency in FpOS1 and no mutations detected in FpOS2.Molecular docking indicated that amino acid substitutions in FpOS4 and FpOS5 significantly reduced the binding affinity of fludioxonil to these target proteins.In conclusion,F.pseudograminearum poses a moderate risk of resistance to fludioxonil.Point mutations in FpOS4 and FpOS5 genes emerge as key molecular drivers of resistance,likely by diminishing the binding affinity between the fungicide and its proteins.This study clarifies the molecular basis of fludioxonil resistance in F.pseudograminearum and provides a scientific rationale for the judicious use of this fungicide in managing FCR.展开更多
With the increasing accumulation of plastic pollutants in various environments,research on microorganisms(including bacteria,fungi,and algae)with plastic degradation capabilities has gained significant attention.Howev...With the increasing accumulation of plastic pollutants in various environments,research on microorganisms(including bacteria,fungi,and algae)with plastic degradation capabilities has gained significant attention.However,only a limited number of microbial plastic-degrading enzymes have been identified to date.This highlights that the degradation mechanisms employed by many plastic-degrading microorganisms,particularly filamentous fungi,remain insufficiently explored.In this study,we utilized a versatile fungal plasmid(pCT74)to express green fluorescent protein(GFP)in a marine-derived fungus Alternaria alternata strain FB1 with plastic degradation capabilities.Upon evaluating the degradation effect of polyester-type polyurethane(PU)film,we observed that different transformants exhibited three kinds of activities(the same,reduced,or enhanced degradation capability)compared to the FB1 wild-type strain.Further analysis of the plasmid fragment insertion sites in different transformants revealed that pCT74 integrates randomly into the genome of the host fungus.Notably,a direct correlation was found between the plasmid insertion site and the degradation capability of the corresponding transformant.Our findings not only redefine the potential applications of plasmid pCT74 in filamentous fungi but also show a novel research approach to identifying key enzymes involved in plastic degradation by fungi.展开更多
OsMAPK6 plays a critical role in regulating rice growth,development,and stress responses.However,the embryonic lethality associated with loss-of-function mutations prevents the generation of homozygous mutant seeds,si...OsMAPK6 plays a critical role in regulating rice growth,development,and stress responses.However,the embryonic lethality associated with loss-of-function mutations prevents the generation of homozygous mutant seeds,significantly hindering functional studies of this gene.Although the weak mutant dsg1 has offered valuable insights into OsMAPK6 function,its extremely low seed-setting rate limits its use for detailed genetic analysis.Here,we employed prime editing to perform precise multi-site modifications at the C-terminus of OsMAPK6,generating a series of osmapk6 mutants with truncated proteins of varying lengths.Among these,the osmapk6(379)and osmapk6(383)mutants exhibited phenotypic defects similar to dsg1,while osmapk6(386)showed a significantly improved seed-setting rate despite persistent developmental defects.Through phenotypic characterization and protein functional analysis,we further clarified how different C-terminal deletion lengths affect plant growth,development,stress responses,and OsMAPK6 protein function.In summary,this study elucidates the importance of the OsMAPK6 C-terminus in rice biology and provides a fertile weak mutant with enhanced seed production,offering a valuable genetic resource for future research on OsMAPK6.展开更多
CRISPR-Cas9 has emerged as a powerful tool for gene editing,and it has been widely used in plant functional genomics research and crop genetic breeding(Chen et al.2019).The target specificity of CRISPR-Cas9 relies on ...CRISPR-Cas9 has emerged as a powerful tool for gene editing,and it has been widely used in plant functional genomics research and crop genetic breeding(Chen et al.2019).The target specificity of CRISPR-Cas9 relies on the 20-base-pair single guide RNA(sgRNA),which makes creating plant-specific mutant libraries through large-scale synthesis of sgRNAs targeting multiple genes or even the whole genome relatively quick and straightforward.展开更多
Naturally occurring yellow leaf mutants are an important resource for studying pigment content and biosynthesis,as well as related gene expression.In our ongoing cultivation of Rehmannia chingii H.L.Li,we found an off...Naturally occurring yellow leaf mutants are an important resource for studying pigment content and biosynthesis,as well as related gene expression.In our ongoing cultivation of Rehmannia chingii H.L.Li,we found an off-type yellow plant.The yellowing started with the new leaves and gradually spread downward until the entire plant exhibited a stable shade of yellow.We studied the differences in the chlorophyll and carotenoid content,carotenoid profile,and transcriptome of this yellow-leaf mutant(P2).Compared to the wild-type R.chingii plant(P1),P2 leaves had significantly lower chlorophyll and carotenoid content.LC-MS/MS analysis revealed that P2 had higher quantities of severalmetabolites in the carotenoid biosynthesis pathway.Transcriptome sequencing results showed that genes involved in porphyrin metabolism,carbon fixation,photosynthesis and antenna proteins,terpenoid backbone biosynthesis,and carotenoid biosynthesis were differentially expressed between P1 and P2.Large-scale expression differences were observed in the phytohormone and MAPK signaling pathways,as well as in 15 transcription factor families.We discuss possible mechanisms responsible for the yellowleaf color in P2.These preliminary data are valuable for further exploring the molecular mechanisms of leaf color formation and associated pathways.展开更多
Background:Innovative oral targeted therapies are warranted for patients with human epidermal growth factor receptor 2(HER2)-mutant non-small-cell lung cancer(NSCLC).Zongertinib is an oral,irreversible,HER2-selective ...Background:Innovative oral targeted therapies are warranted for patients with human epidermal growth factor receptor 2(HER2)-mutant non-small-cell lung cancer(NSCLC).Zongertinib is an oral,irreversible,HER2-selective tyrosine kinase inhibitor that has been shown to have efficacy in persons with advanced or metastatic solid tumors with HER2 alterations in a phase 1 study.展开更多
A high yielding rice mutant ( Oryza sativa L. cv. Zhenhui 249) with low chlorophyll b was recently discovered in the field. The mutant was mainly characterized by the decrease of the content of extrinsic antennae c...A high yielding rice mutant ( Oryza sativa L. cv. Zhenhui 249) with low chlorophyll b was recently discovered in the field. The mutant was mainly characterized by the decrease of the content of extrinsic antennae complex. This variation was shown in the stage when the leaves were expanding. When the leaves are at the final developmental stage, the content would approach to that of the wild type. It was discovered that only moderate amount of chlorophyll b decreased in this mutant. The photosynthetic apparatus of the mutant was rather stable in the whole life span of the leaf. The extrinsic antennae complex of the mutant might make efficient use of light and meanwhile reduce the production of O -· 2.展开更多
[Objective] The mitigative effect of antioxidase system of a rice mutant with low chlorophyll b on photooxidative damage was studied.[Method] A rice mutant with low chlorophyll b and its wild type were taken as experi...[Objective] The mitigative effect of antioxidase system of a rice mutant with low chlorophyll b on photooxidative damage was studied.[Method] A rice mutant with low chlorophyll b and its wild type were taken as experimental materials to comparatively research their peroxide (H2O2) contents, the activity and isozymes of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in chloroplast.[Result] Compared with the wild type, there were many kinds of SOD, POD and CAT isozymes in leaf cells and chloroplast cell of mutant, and the activity of SOD, POD and CAT isozymes in leaf cells and chloroplast cell of mutant was also correspondingly higher. Under intense light condition, the H2O2 content of chloroplast in mutant was less than that in the wild type. [Conclusion] The higher activity of scavenging active oxygen can relieve the photooxidative damage made by excessive light energy of intense light on photosynthetic membrane, which is an important reason for higher photosystem Ⅱ (PS II) stability of this mutant.展开更多
[ Objective ] The study aimed to reveal the genetic model of a biomass mutant in Oryza sativa. [ Method ] In the process of screening and identification of Bar-transgenic rice, a biomass mutant was found in 10 lines o...[ Objective ] The study aimed to reveal the genetic model of a biomass mutant in Oryza sativa. [ Method ] In the process of screening and identification of Bar-transgenic rice, a biomass mutant was found in 10 lines of T1 progenies. The mutant was investigated for genetic analysis and agronomic traits by herbicide spraying and PCR amplification. [ Result] The segregation ratio is consistent with mendelian law（3：1）. The mutant assumed not only higher plant height, wider straw and earlier florescence, but also more tillers, bigger spikes and resultantly higher biomass. PCR detections indicated that no co-segregation was observed between mutant traits and target gene（Bar） in the T-DNA inserted, proving that the mutant is not caused by the insertion of T-DNA containing target gene （Bar）. [ Conclusion] Our study may avail to understand the cloning of mutant gene and the mechanism of the mutant gene on biomass.展开更多
[Objective] The aim of this study is to understand the genetic characteristics of a grain shape mutant and its possible role in genetic improvement of grain yield in rice. [Method] On the basis of the collection of T-...[Objective] The aim of this study is to understand the genetic characteristics of a grain shape mutant and its possible role in genetic improvement of grain yield in rice. [Method] On the basis of the collection of T-DNA tag lines, the progeny of homozygous plants carrying T-DNA insertion were screened for mutants with mutated phenotypes. The genetic analysis of the mutant and test for the linkage between the mutated phenotype and the T-DNA insertion were carried out to determine its genetic characteristics. [Result] In the present study, a grain shape mutant induced by T-DNA insertion in rice was identified, which showed small grain. Genetic analysis of the mutant showed that the two types of phenotype, normal and small grain in the segregating populations derived from the T-DNA heterozygotes, fit the ratio of 3∶1. Test for Basta resistance showed that all the mutants were resistant while the normal plants segregated for resistant and susceptible by the ratio of 2∶1. The results indicated that the mutant phenotype cosegregated with Bar gene. The small grain mutant caused by T-DNA insertion was confirmed by PCR amplification aiming at T-DNA. [Conclusion] The grain shape mutant is useful for isolation of the tagged gene and genetic improvement in rice.展开更多
[Objective] The 15urpose was to seek for the different phenotypes between wild type and Arabidopsis Mutants in response to CO2. [Method] The epidermis bioassays and seed germination test were carried out to analyze th...[Objective] The 15urpose was to seek for the different phenotypes between wild type and Arabidopsis Mutants in response to CO2. [Method] The epidermis bioassays and seed germination test were carried out to analyze the physiological characteristics of two Arabidopsis mu- tants and their wild type. [Result] There existed distinct differences in stomata apertures, water loss and leaf temperature compared with wild type except for stomata density. In addition, seed germination test on the medium indicated that cdfl was insensitive to ABA, mannitol and NaCI, but cdsl performed contrary to cdil. [ Conclusion] There are some different physiological characteristics between wild type and mutants.展开更多
[Objective] The aim was to improve the genetic property of peppers, the mutant population of Capsicum annuum L cultivar ＂6421＂ was constructed. [Method] The seeds of ＂6421＂ were treated with 0.2% to 1.2% ethyl met...[Objective] The aim was to improve the genetic property of peppers, the mutant population of Capsicum annuum L cultivar ＂6421＂ was constructed. [Method] The seeds of ＂6421＂ were treated with 0.2% to 1.2% ethyl methane sulfonate to identified LD50, and then 10 000 LD^o of treated seeds were sowed to construct mutant population. The agronomic characters and genetic regularity of dwarf mutants in M4 generation were analyzed. [Result] Our results showed that GR and SSR were 45.2% and 40.2% respectively at 1.0% EMS, close to LD50, with GI （17.6） and seed Ⅵ （19.7） being half of that of control; 562 M4 mutants were identified in 2015, and the mutation could be characterized according 11 major categories and 32 subcategories; Simultaneously, we found that plant height, plant width, diameter of mainstem, length of main-stem, the number of main-stem nodes and branch of lines E29, E58, E142 and E312 were all significantly different from that of the control. The mutation of lines E29, E58 and E312 was all controlled by a single recessive gene. [Conclusionl The study first created a pepper mutant population, which provides not only the germplasm resources for further breeding but also direct and effective materials for genomic study of the pepper.展开更多
[Objective] The aim of this study was to screen Saccharomyces for glutathione over-production. [Method] Ethionine-resistant mutants were obtained through UV mutagenesis and rational screening. [Result] A high GSH-prod...[Objective] The aim of this study was to screen Saccharomyces for glutathione over-production. [Method] Ethionine-resistant mutants were obtained through UV mutagenesis and rational screening. [Result] A high GSH-producing strain HSJB1 was isolated from soil, and the biomass for this strain by flask shaking fermentation was 3.87 g/L while the GSH yield was 91.87 mg/L. According to the morphological, physiological and biochemical characteristics of cells, this strain was primarily identified as Saccharomyces cerevisiae. An ethionine-resistant mutant YBS77 was obtained through UV mutagenesis of the original strain HSJB1, and the biomass for this strain by flask shaking fermentation was 7.60 g dry cell weight/L while the GSH yield was 211.96 mg/L. [Conclusion] The biomass of the mutant obtained by breeding is increased by 96.38% than that of the original strain, and the GSH yield of the mutant obtained by breeding is increased by 130.72% than that from the original strain, which indicates that the breeding method is feasible.展开更多
[Objective] The aim was to explore the relevance between decreased 1 000-grain weight and grain-filling characteristics of rice giant embryo mutant.[Method] Richards equation was used to describe grain filling process...[Objective] The aim was to explore the relevance between decreased 1 000-grain weight and grain-filling characteristics of rice giant embryo mutant.[Method] Richards equation was used to describe grain filling processes of giant embryo mutant MH-ge1 and its corresponding wild type so as to analyze the parameters of grain-filling characteristics of materials.[Result] The initial filling power of mutant MH-ge1 was higher than the wild type MH86,however,the maximum filling rate,the mean filling rate and the final increment of mutant MH-ge1 was lower than those of MH86.[Conclusion] The grain-filling characteristics of mutant MH-ge1 were poorer than the wild type MH86,thus resulting in the decrease of the grain weight of the giant embryo rice.展开更多
基金Supported by Funding from the Henan Provincial Scientific and Technological Breakthrough Project(No.242102111113).
文摘Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide fludioxonil is a key agent for FCR control.Previous studies indicated that resistance to fludioxonil in F.pseudograminearum is primarily associated with altered expression levels of the FpOS1 gene,which encodes a hybrid histidine kinase.However,the roles of mutations in other FpOS genes and the molecular interactions between FpOS proteins and fludioxonil remain elusive.To address these gaps,we generated 16 fludioxonil-resistant mutants with heritable resistance traits by in vitro selection of four sensitive F.pseudograminearum isolates.These mutants exhibited high resistance levels,with resistance factors(RF)ranging from 633.73 to 8617.07.Compared to their parental isolates,the resistant mutants showed significantly reduced mycelial growth rate,sporulation capacity,and pathogenicity.They were also more sensitive to ionic,osmotic,and oxidative stresses and displayed compromised cell wall and membrane integrity.Fludioxonil demonstrated no cross-resistance with tebuconazole or pydiflumetofen;however,it exhibited weak positive crossresistance to pyraclostrobin and moderate positive cross-resistance to iprodione.Fludioxonil treatment significantly promoted glycerol synthesis and inhibited deoxynivalenol(DON)production in parental isolates,whereas these regulatory effects were markedly attenuated in the resistant mutants.Mutation analysis identified mutation sites in FpOS1,FpOS4,and FpOS5 genes,with a lower mutation frequency in FpOS1 and no mutations detected in FpOS2.Molecular docking indicated that amino acid substitutions in FpOS4 and FpOS5 significantly reduced the binding affinity of fludioxonil to these target proteins.In conclusion,F.pseudograminearum poses a moderate risk of resistance to fludioxonil.Point mutations in FpOS4 and FpOS5 genes emerge as key molecular drivers of resistance,likely by diminishing the binding affinity between the fungicide and its proteins.This study clarifies the molecular basis of fludioxonil resistance in F.pseudograminearum and provides a scientific rationale for the judicious use of this fungicide in managing FCR.
基金Supported by the Science and Technology Innovation Project of Laoshan Laboratory(Nos.2022QNLM030004-3,LSKJ202203103)the NSFC Innovative Group Grant(No.42221005)+5 种基金the Key Collaborative Research Program of the Alliance of International Science Organizations(No.ANSO-CR-KP-2022-08)the Shandong Provincial Natural Science Foundation(No.ZR2021ZD28)the Major Research Plan of the National Natural Science Foundation(No.92351301)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA22050301)the Taishan Scholars Program(No.tstp20230637)the Qingdao Natural Science Foundation(No.23-2-1-182-zyyd-jch)。
文摘With the increasing accumulation of plastic pollutants in various environments,research on microorganisms(including bacteria,fungi,and algae)with plastic degradation capabilities has gained significant attention.However,only a limited number of microbial plastic-degrading enzymes have been identified to date.This highlights that the degradation mechanisms employed by many plastic-degrading microorganisms,particularly filamentous fungi,remain insufficiently explored.In this study,we utilized a versatile fungal plasmid(pCT74)to express green fluorescent protein(GFP)in a marine-derived fungus Alternaria alternata strain FB1 with plastic degradation capabilities.Upon evaluating the degradation effect of polyester-type polyurethane(PU)film,we observed that different transformants exhibited three kinds of activities(the same,reduced,or enhanced degradation capability)compared to the FB1 wild-type strain.Further analysis of the plasmid fragment insertion sites in different transformants revealed that pCT74 integrates randomly into the genome of the host fungus.Notably,a direct correlation was found between the plasmid insertion site and the degradation capability of the corresponding transformant.Our findings not only redefine the potential applications of plasmid pCT74 in filamentous fungi but also show a novel research approach to identifying key enzymes involved in plastic degradation by fungi.
基金supported by the National Natural Science Foundation of China(Grant Nos.32441024,32572315,and U25A20674)the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2021229)+1 种基金the Heilongjiang Key Research and Development Program,China(Grant No.2025ZX04B02)the Young Scientist Group Project of Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences(Grant No.2023QNXZ02).
文摘OsMAPK6 plays a critical role in regulating rice growth,development,and stress responses.However,the embryonic lethality associated with loss-of-function mutations prevents the generation of homozygous mutant seeds,significantly hindering functional studies of this gene.Although the weak mutant dsg1 has offered valuable insights into OsMAPK6 function,its extremely low seed-setting rate limits its use for detailed genetic analysis.Here,we employed prime editing to perform precise multi-site modifications at the C-terminus of OsMAPK6,generating a series of osmapk6 mutants with truncated proteins of varying lengths.Among these,the osmapk6(379)and osmapk6(383)mutants exhibited phenotypic defects similar to dsg1,while osmapk6(386)showed a significantly improved seed-setting rate despite persistent developmental defects.Through phenotypic characterization and protein functional analysis,we further clarified how different C-terminal deletion lengths affect plant growth,development,stress responses,and OsMAPK6 protein function.In summary,this study elucidates the importance of the OsMAPK6 C-terminus in rice biology and provides a fertile weak mutant with enhanced seed production,offering a valuable genetic resource for future research on OsMAPK6.
基金supported by the National Natural Science Foundation of China(32272670 and 31972986)the Key Research and Development Program of Shaanxi Province,China(2023-YBNY-059)。
文摘CRISPR-Cas9 has emerged as a powerful tool for gene editing,and it has been widely used in plant functional genomics research and crop genetic breeding(Chen et al.2019).The target specificity of CRISPR-Cas9 relies on the 20-base-pair single guide RNA(sgRNA),which makes creating plant-specific mutant libraries through large-scale synthesis of sgRNAs targeting multiple genes or even the whole genome relatively quick and straightforward.
基金funded by the Beijing Gardening andGreeningYouth InnovationTalent Support Program(kjcx202336)theKey R&D Project of theOpen Subject of the Beijing Key Laboratory for Greening Plant Breeding(YZZD202403).
文摘Naturally occurring yellow leaf mutants are an important resource for studying pigment content and biosynthesis,as well as related gene expression.In our ongoing cultivation of Rehmannia chingii H.L.Li,we found an off-type yellow plant.The yellowing started with the new leaves and gradually spread downward until the entire plant exhibited a stable shade of yellow.We studied the differences in the chlorophyll and carotenoid content,carotenoid profile,and transcriptome of this yellow-leaf mutant(P2).Compared to the wild-type R.chingii plant(P1),P2 leaves had significantly lower chlorophyll and carotenoid content.LC-MS/MS analysis revealed that P2 had higher quantities of severalmetabolites in the carotenoid biosynthesis pathway.Transcriptome sequencing results showed that genes involved in porphyrin metabolism,carbon fixation,photosynthesis and antenna proteins,terpenoid backbone biosynthesis,and carotenoid biosynthesis were differentially expressed between P1 and P2.Large-scale expression differences were observed in the phytohormone and MAPK signaling pathways,as well as in 15 transcription factor families.We discuss possible mechanisms responsible for the yellowleaf color in P2.These preliminary data are valuable for further exploring the molecular mechanisms of leaf color formation and associated pathways.
基金Funded by Boehringer IngelheimBeamion LUNG-1 ClinicalTrials.gov number,NCT04886804.
文摘Background:Innovative oral targeted therapies are warranted for patients with human epidermal growth factor receptor 2(HER2)-mutant non-small-cell lung cancer(NSCLC).Zongertinib is an oral,irreversible,HER2-selective tyrosine kinase inhibitor that has been shown to have efficacy in persons with advanced or metastatic solid tumors with HER2 alterations in a phase 1 study.
文摘A high yielding rice mutant ( Oryza sativa L. cv. Zhenhui 249) with low chlorophyll b was recently discovered in the field. The mutant was mainly characterized by the decrease of the content of extrinsic antennae complex. This variation was shown in the stage when the leaves were expanding. When the leaves are at the final developmental stage, the content would approach to that of the wild type. It was discovered that only moderate amount of chlorophyll b decreased in this mutant. The photosynthetic apparatus of the mutant was rather stable in the whole life span of the leaf. The extrinsic antennae complex of the mutant might make efficient use of light and meanwhile reduce the production of O -· 2.
文摘[Objective] The mitigative effect of antioxidase system of a rice mutant with low chlorophyll b on photooxidative damage was studied.[Method] A rice mutant with low chlorophyll b and its wild type were taken as experimental materials to comparatively research their peroxide (H2O2) contents, the activity and isozymes of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in chloroplast.[Result] Compared with the wild type, there were many kinds of SOD, POD and CAT isozymes in leaf cells and chloroplast cell of mutant, and the activity of SOD, POD and CAT isozymes in leaf cells and chloroplast cell of mutant was also correspondingly higher. Under intense light condition, the H2O2 content of chloroplast in mutant was less than that in the wild type. [Conclusion] The higher activity of scavenging active oxygen can relieve the photooxidative damage made by excessive light energy of intense light on photosynthetic membrane, which is an important reason for higher photosystem Ⅱ (PS II) stability of this mutant.
文摘[ Objective ] The study aimed to reveal the genetic model of a biomass mutant in Oryza sativa. [ Method ] In the process of screening and identification of Bar-transgenic rice, a biomass mutant was found in 10 lines of T1 progenies. The mutant was investigated for genetic analysis and agronomic traits by herbicide spraying and PCR amplification. [ Result] The segregation ratio is consistent with mendelian law（3：1）. The mutant assumed not only higher plant height, wider straw and earlier florescence, but also more tillers, bigger spikes and resultantly higher biomass. PCR detections indicated that no co-segregation was observed between mutant traits and target gene（Bar） in the T-DNA inserted, proving that the mutant is not caused by the insertion of T-DNA containing target gene （Bar）. [ Conclusion] Our study may avail to understand the cloning of mutant gene and the mechanism of the mutant gene on biomass.
文摘[Objective] The aim of this study is to understand the genetic characteristics of a grain shape mutant and its possible role in genetic improvement of grain yield in rice. [Method] On the basis of the collection of T-DNA tag lines, the progeny of homozygous plants carrying T-DNA insertion were screened for mutants with mutated phenotypes. The genetic analysis of the mutant and test for the linkage between the mutated phenotype and the T-DNA insertion were carried out to determine its genetic characteristics. [Result] In the present study, a grain shape mutant induced by T-DNA insertion in rice was identified, which showed small grain. Genetic analysis of the mutant showed that the two types of phenotype, normal and small grain in the segregating populations derived from the T-DNA heterozygotes, fit the ratio of 3∶1. Test for Basta resistance showed that all the mutants were resistant while the normal plants segregated for resistant and susceptible by the ratio of 2∶1. The results indicated that the mutant phenotype cosegregated with Bar gene. The small grain mutant caused by T-DNA insertion was confirmed by PCR amplification aiming at T-DNA. [Conclusion] The grain shape mutant is useful for isolation of the tagged gene and genetic improvement in rice.
文摘[Objective] The 15urpose was to seek for the different phenotypes between wild type and Arabidopsis Mutants in response to CO2. [Method] The epidermis bioassays and seed germination test were carried out to analyze the physiological characteristics of two Arabidopsis mu- tants and their wild type. [Result] There existed distinct differences in stomata apertures, water loss and leaf temperature compared with wild type except for stomata density. In addition, seed germination test on the medium indicated that cdfl was insensitive to ABA, mannitol and NaCI, but cdsl performed contrary to cdil. [ Conclusion] There are some different physiological characteristics between wild type and mutants.
基金Supported by Natural Science Foundation of Hunan(2016JJ6064)China Agriculture Research System(CARS-25-A-8)~~
文摘[Objective] The aim was to improve the genetic property of peppers, the mutant population of Capsicum annuum L cultivar ＂6421＂ was constructed. [Method] The seeds of ＂6421＂ were treated with 0.2% to 1.2% ethyl methane sulfonate to identified LD50, and then 10 000 LD^o of treated seeds were sowed to construct mutant population. The agronomic characters and genetic regularity of dwarf mutants in M4 generation were analyzed. [Result] Our results showed that GR and SSR were 45.2% and 40.2% respectively at 1.0% EMS, close to LD50, with GI （17.6） and seed Ⅵ （19.7） being half of that of control; 562 M4 mutants were identified in 2015, and the mutation could be characterized according 11 major categories and 32 subcategories; Simultaneously, we found that plant height, plant width, diameter of mainstem, length of main-stem, the number of main-stem nodes and branch of lines E29, E58, E142 and E312 were all significantly different from that of the control. The mutation of lines E29, E58 and E312 was all controlled by a single recessive gene. [Conclusionl The study first created a pepper mutant population, which provides not only the germplasm resources for further breeding but also direct and effective materials for genomic study of the pepper.
基金Supported by Scientific Research Project of Liaoning Educational Department(20060154)Initial Funds for Doctors in Dalian Nationalities University(20066206)~~
文摘[Objective] The aim of this study was to screen Saccharomyces for glutathione over-production. [Method] Ethionine-resistant mutants were obtained through UV mutagenesis and rational screening. [Result] A high GSH-producing strain HSJB1 was isolated from soil, and the biomass for this strain by flask shaking fermentation was 3.87 g/L while the GSH yield was 91.87 mg/L. According to the morphological, physiological and biochemical characteristics of cells, this strain was primarily identified as Saccharomyces cerevisiae. An ethionine-resistant mutant YBS77 was obtained through UV mutagenesis of the original strain HSJB1, and the biomass for this strain by flask shaking fermentation was 7.60 g dry cell weight/L while the GSH yield was 211.96 mg/L. [Conclusion] The biomass of the mutant obtained by breeding is increased by 96.38% than that of the original strain, and the GSH yield of the mutant obtained by breeding is increased by 130.72% than that from the original strain, which indicates that the breeding method is feasible.
基金Supported by International Atomic Energy Agency(120609/R0)Scientific and Research Development Foundation of Zhejiang Agriculture and Forest University(2351000977)~~
文摘[Objective] The aim was to explore the relevance between decreased 1 000-grain weight and grain-filling characteristics of rice giant embryo mutant.[Method] Richards equation was used to describe grain filling processes of giant embryo mutant MH-ge1 and its corresponding wild type so as to analyze the parameters of grain-filling characteristics of materials.[Result] The initial filling power of mutant MH-ge1 was higher than the wild type MH86,however,the maximum filling rate,the mean filling rate and the final increment of mutant MH-ge1 was lower than those of MH86.[Conclusion] The grain-filling characteristics of mutant MH-ge1 were poorer than the wild type MH86,thus resulting in the decrease of the grain weight of the giant embryo rice.
