Drought is a major constraint in maize production worldwide.We studied quantitative trait loci(QTL)underlying drought tolerance for maize plants grown in two different environments.Traits investigated included ASI,pla...Drought is a major constraint in maize production worldwide.We studied quantitative trait loci(QTL)underlying drought tolerance for maize plants grown in two different environments.Traits investigated included ASI,plant height,grain yield,ear height,and ear setting.A genetic linkage map was constructed with 120 simple sequence repeat(SSR)markers based on an F2 population derived from a cross between D5(resistant parent)and 7924(susceptible parent).Correlation and heritability were calculated.QTLs of these traits were identified by composite interval mapping combined with a linkage map covering 1790.3 cM.The markers were arranged in ten linkage groups.QTL mapping was made of the mean trait performance of the 180 F2:3 population.The results showed five,five,six,four,and five QTLs for ASI,plant height,grain yield,ear height,and ear setting under full irrigation condition,respectively,and four,seven,six,four,and four QTLs for ASI,plant height,grain yield,ear height,and ear setting under severe late stress conditions,respectively.Especially the four QTLs detected for five traits in 2008 and 2009.The universal QTLs information generated in this study will aid in undertaking an integrated breeding strategy for further genetic studies in drought tolerance improvement in maize.展开更多
Starch branching enzyme(SBE)catalyzes the biosynthesis of amylopectin.We described the isolation and characterization of SBEIIb promoter and their expression patterns in transgenic tobacco.Using the genomic DNA of mai...Starch branching enzyme(SBE)catalyzes the biosynthesis of amylopectin.We described the isolation and characterization of SBEIIb promoter and their expression patterns in transgenic tobacco.Using the genomic DNA of maize cultivar Lunuo 1 as template,the SBEIIb promoter was isolated by PCR and was cloned into pMD18-T vector.To study SEBIIb gene regulation at the cellular level,SBEIIb promoter was fused to the^-glucuronidase(GUS)report gene.The results of the fluorometric GUS assays indicate that the sbeⅡb-GUS fusion directed a seed-specific expression.Four series of constructs were made with the promoter and the GUS reporter gene to investigate the cis-acting analysis,showing that the four different constructs all can drive expression of the GUS gene in seed plumule and cotyledon and the GUS activity was apparently decreased with the progressive loss of promoter 5'end.展开更多
基金supported by the National Basic Research Program of China(2009CB118400)
文摘Drought is a major constraint in maize production worldwide.We studied quantitative trait loci(QTL)underlying drought tolerance for maize plants grown in two different environments.Traits investigated included ASI,plant height,grain yield,ear height,and ear setting.A genetic linkage map was constructed with 120 simple sequence repeat(SSR)markers based on an F2 population derived from a cross between D5(resistant parent)and 7924(susceptible parent).Correlation and heritability were calculated.QTLs of these traits were identified by composite interval mapping combined with a linkage map covering 1790.3 cM.The markers were arranged in ten linkage groups.QTL mapping was made of the mean trait performance of the 180 F2:3 population.The results showed five,five,six,four,and five QTLs for ASI,plant height,grain yield,ear height,and ear setting under full irrigation condition,respectively,and four,seven,six,four,and four QTLs for ASI,plant height,grain yield,ear height,and ear setting under severe late stress conditions,respectively.Especially the four QTLs detected for five traits in 2008 and 2009.The universal QTLs information generated in this study will aid in undertaking an integrated breeding strategy for further genetic studies in drought tolerance improvement in maize.
基金supported by the projects in the National Key Technologies R&D Program during the 11th Five-Year Plan period of China(2006BAD01A03)
文摘Starch branching enzyme(SBE)catalyzes the biosynthesis of amylopectin.We described the isolation and characterization of SBEIIb promoter and their expression patterns in transgenic tobacco.Using the genomic DNA of maize cultivar Lunuo 1 as template,the SBEIIb promoter was isolated by PCR and was cloned into pMD18-T vector.To study SEBIIb gene regulation at the cellular level,SBEIIb promoter was fused to the^-glucuronidase(GUS)report gene.The results of the fluorometric GUS assays indicate that the sbeⅡb-GUS fusion directed a seed-specific expression.Four series of constructs were made with the promoter and the GUS reporter gene to investigate the cis-acting analysis,showing that the four different constructs all can drive expression of the GUS gene in seed plumule and cotyledon and the GUS activity was apparently decreased with the progressive loss of promoter 5'end.
