To eliminate thermal stress and cracks in the process of laser cladding, a kind of bioceramic coating with gradient compositional design was prepared on the surface of Ti alloy by using wide-band laser cladding. And e...To eliminate thermal stress and cracks in the process of laser cladding, a kind of bioceramic coating with gradient compositional design was prepared on the surface of Ti alloy by using wide-band laser cladding. And effect of Y2O3 content on gradient bioceramic composite coating was studied. The experimental results indicate that adding rare earth can refine grain. Different rare earth contents affect formation of HA and β-TCP in bioceramic coating. When the content of rare earth ranges from 0.4% to 0.6%, the active extent of rare earth in synthesizing HA and β-TCP is the best, which indicates that “monosodium glutamate” effect of rare earth plays a dominant role. However, when rare earth content is up to 0.8%, the amount of synthesizing HA and β-TCP in coating conversely goes down, which demonstrates that rare earth gradually losts its catalysis in manufacturing HA and β-TCP.展开更多
Starch is the most important component in endosperm of sorghum grain.Usually,two types of starch are present:amylose(AM)and amylopectin(AP).The levels of AM and AP contents play a significant role in the appearance,st...Starch is the most important component in endosperm of sorghum grain.Usually,two types of starch are present:amylose(AM)and amylopectin(AP).The levels of AM and AP contents play a significant role in the appearance,structure,and quality of sorghum grains and in marketing applications.In the present study,a panel of 634 sorghum(Sorghum bicolor(L.)Moench)accessions were evaluated for starch,AM,and AP contents of grain,which included a mini core collection of 242 accessions from the International Crops Research Institute for the Semi-Arid Tropics(ICRISAT)in India,and 252 landraces and 140 cultivars from China.The average starch content was 67.64%and the average AM and AP contents were 20.19 and 79.81%,respectively.We developed a total of 260000 high-confidence single nucleotide polymorphism(SNP)markers in the panel of 634 accessions of S.bicolor using specific locus amplified fragment sequencing(SLAF-seq).We performed genome-wide association studies(GWAS)of starch,AM,and AM/AP of grain and SNP markers based on a mixed linear model(MLM).In total,70 significant association signals were detected for starch,AM,and AM/AP ratio of grain with P<4.452×10^-7,of which 10 SNPs were identified with significant starch,51 SNPs were associated with AM,and nine SNPs were associated with the AM/AP ratio.The Gene Ontology(GO)analysis identified 12 candidate genes at five QTLs associated with starch metabolism within the 200-kb intervals,located on chromosomes 1,5,6,and 9.Of these genes,Sobic.006G036500.1 encodes peptidyl-prolyl cis-trans-isomerase CYP38 responsible for hexose monophosphate shunt(HMS)and Sobic.009G071800 encodes 6-phospho-fructokinase(PFK),which is involved in the embden-meyerhof pathway(EMP).Kompetitive allele specific PCR(KASP)markers were developed to validate the GWAS results.The C allele is correlated with a high starch content,while the T allele is linked with a low level of starch content,and provides reliable haplotypes for MAS in sorghum quality improvement.展开更多
玉米籽粒氮含量与品质紧密相关,其遗传机制的解析对玉米品质育种具有重要意义。本研究以252份玉米自交系为关联群体,利用贝叶斯信息与连锁不平衡迭代嵌套式模型(BLINK,bayesian-informationandlinkage-disequilibrium iteratively neste...玉米籽粒氮含量与品质紧密相关,其遗传机制的解析对玉米品质育种具有重要意义。本研究以252份玉米自交系为关联群体,利用贝叶斯信息与连锁不平衡迭代嵌套式模型(BLINK,bayesian-informationandlinkage-disequilibrium iteratively nested keyway)、固定随机循环概率模型(FarmCPU,fixed and random model circulating probability unification)、一般线性模型(GLM,general linear model)、混合线性模型(MLM,mixed linear model)、多位点混合线性模型(MLMM,multiple loci mixed model)和逐步排它性混合线性模型(SUPER,settlement of MLM under progressively exclusive relationship)等方法分别对其籽粒氮含量进行全基因组关联分析。共鉴定到13个与籽粒氮含量显著关联的SNP(P<3.64E-07)。BLINK、FarmCPU、GLM、MLM、MLMM和SUPER方法分别检测到6个、3个、7个、4个、2个和4个SNP位点。其中,S3_8879213在5种方法中均能检测到,S9_146173702在4种方法中均能检测到,S5_114774030和S7_182217338在3种方法中均能检测到,S1_10906326和S1_177528813在2种方法中均能检测到。共挖掘25个相关候选基因,其中Zm00001eb275080和Zm00001eb330700可能是影响玉米籽粒氮含量的重要候选基因。展开更多
通过挖掘水稻籽粒中锌含量显著关联的QTL,并结合基因功能注释、单倍型和灌浆期籽粒相对表达量分析,筛选与水稻籽粒锌含量相关的候选基因。本研究以139份西北早粳稻核心种质资源为试验材料,结合重测序获得的1800920个高可信度SNPs,基于...通过挖掘水稻籽粒中锌含量显著关联的QTL,并结合基因功能注释、单倍型和灌浆期籽粒相对表达量分析,筛选与水稻籽粒锌含量相关的候选基因。本研究以139份西北早粳稻核心种质资源为试验材料,结合重测序获得的1800920个高可信度SNPs,基于一般线性模型(GLM,general linear model)进行全基因组关联分析,对显著QTL区间内候选基因进行功能注释,并对进一步筛选后的基因进行单倍型和籽粒灌浆期相对表达量分析,以期筛选出与籽粒锌含量相关的候选基因和优势单倍型。结果表明,139份水稻中籽粒锌含量存在丰富的表型变异,且符合正态分布。全基因组关联分析共关联到12个显著SNP,分布在第1、2、4、10、11号染色体上,结合候选区间内的基因功能注释,推测定位在囊泡中的OsFRDL2可能与水稻籽粒锌元素富集相关;单倍型和灌浆期籽粒相对表达量分析表明,OsFRDL2在优势单倍型Hap5中表达量相对较高。因此推测OsFRDL2可能与水稻籽粒锌元素富集相关。研究结果为解析水稻籽粒锌元素富集机制和开发富锌水稻分子标记提供理论基础,为培育富锌水稻提供基因资源。展开更多
基金Project supported by Governor's Foundation of Guizhou Province (2004-07)
文摘To eliminate thermal stress and cracks in the process of laser cladding, a kind of bioceramic coating with gradient compositional design was prepared on the surface of Ti alloy by using wide-band laser cladding. And effect of Y2O3 content on gradient bioceramic composite coating was studied. The experimental results indicate that adding rare earth can refine grain. Different rare earth contents affect formation of HA and β-TCP in bioceramic coating. When the content of rare earth ranges from 0.4% to 0.6%, the active extent of rare earth in synthesizing HA and β-TCP is the best, which indicates that “monosodium glutamate” effect of rare earth plays a dominant role. However, when rare earth content is up to 0.8%, the amount of synthesizing HA and β-TCP in coating conversely goes down, which demonstrates that rare earth gradually losts its catalysis in manufacturing HA and β-TCP.
基金supported by the earmarked fund for China Agriculture Research System (CARS-06)
文摘Starch is the most important component in endosperm of sorghum grain.Usually,two types of starch are present:amylose(AM)and amylopectin(AP).The levels of AM and AP contents play a significant role in the appearance,structure,and quality of sorghum grains and in marketing applications.In the present study,a panel of 634 sorghum(Sorghum bicolor(L.)Moench)accessions were evaluated for starch,AM,and AP contents of grain,which included a mini core collection of 242 accessions from the International Crops Research Institute for the Semi-Arid Tropics(ICRISAT)in India,and 252 landraces and 140 cultivars from China.The average starch content was 67.64%and the average AM and AP contents were 20.19 and 79.81%,respectively.We developed a total of 260000 high-confidence single nucleotide polymorphism(SNP)markers in the panel of 634 accessions of S.bicolor using specific locus amplified fragment sequencing(SLAF-seq).We performed genome-wide association studies(GWAS)of starch,AM,and AM/AP of grain and SNP markers based on a mixed linear model(MLM).In total,70 significant association signals were detected for starch,AM,and AM/AP ratio of grain with P<4.452×10^-7,of which 10 SNPs were identified with significant starch,51 SNPs were associated with AM,and nine SNPs were associated with the AM/AP ratio.The Gene Ontology(GO)analysis identified 12 candidate genes at five QTLs associated with starch metabolism within the 200-kb intervals,located on chromosomes 1,5,6,and 9.Of these genes,Sobic.006G036500.1 encodes peptidyl-prolyl cis-trans-isomerase CYP38 responsible for hexose monophosphate shunt(HMS)and Sobic.009G071800 encodes 6-phospho-fructokinase(PFK),which is involved in the embden-meyerhof pathway(EMP).Kompetitive allele specific PCR(KASP)markers were developed to validate the GWAS results.The C allele is correlated with a high starch content,while the T allele is linked with a low level of starch content,and provides reliable haplotypes for MAS in sorghum quality improvement.
文摘玉米籽粒氮含量与品质紧密相关,其遗传机制的解析对玉米品质育种具有重要意义。本研究以252份玉米自交系为关联群体,利用贝叶斯信息与连锁不平衡迭代嵌套式模型(BLINK,bayesian-informationandlinkage-disequilibrium iteratively nested keyway)、固定随机循环概率模型(FarmCPU,fixed and random model circulating probability unification)、一般线性模型(GLM,general linear model)、混合线性模型(MLM,mixed linear model)、多位点混合线性模型(MLMM,multiple loci mixed model)和逐步排它性混合线性模型(SUPER,settlement of MLM under progressively exclusive relationship)等方法分别对其籽粒氮含量进行全基因组关联分析。共鉴定到13个与籽粒氮含量显著关联的SNP(P<3.64E-07)。BLINK、FarmCPU、GLM、MLM、MLMM和SUPER方法分别检测到6个、3个、7个、4个、2个和4个SNP位点。其中,S3_8879213在5种方法中均能检测到,S9_146173702在4种方法中均能检测到,S5_114774030和S7_182217338在3种方法中均能检测到,S1_10906326和S1_177528813在2种方法中均能检测到。共挖掘25个相关候选基因,其中Zm00001eb275080和Zm00001eb330700可能是影响玉米籽粒氮含量的重要候选基因。
文摘通过挖掘水稻籽粒中锌含量显著关联的QTL,并结合基因功能注释、单倍型和灌浆期籽粒相对表达量分析,筛选与水稻籽粒锌含量相关的候选基因。本研究以139份西北早粳稻核心种质资源为试验材料,结合重测序获得的1800920个高可信度SNPs,基于一般线性模型(GLM,general linear model)进行全基因组关联分析,对显著QTL区间内候选基因进行功能注释,并对进一步筛选后的基因进行单倍型和籽粒灌浆期相对表达量分析,以期筛选出与籽粒锌含量相关的候选基因和优势单倍型。结果表明,139份水稻中籽粒锌含量存在丰富的表型变异,且符合正态分布。全基因组关联分析共关联到12个显著SNP,分布在第1、2、4、10、11号染色体上,结合候选区间内的基因功能注释,推测定位在囊泡中的OsFRDL2可能与水稻籽粒锌元素富集相关;单倍型和灌浆期籽粒相对表达量分析表明,OsFRDL2在优势单倍型Hap5中表达量相对较高。因此推测OsFRDL2可能与水稻籽粒锌元素富集相关。研究结果为解析水稻籽粒锌元素富集机制和开发富锌水稻分子标记提供理论基础,为培育富锌水稻提供基因资源。
