Fine Mapping Of An Endosperm Mutation Gene Dek In Maize

Maize is the main source of food,forage and industrial raw materials,which plays a vital role in development of national economy.With the increase of population and decrease of arable land,the status of maize will be more important.Hundred-kernel weight is one of the three components for grain yield,which is mainly determined by the kernel traits.Grain can be divided into two main components of embryo and endosperm,and endosperms accounts for about 70-80%of the grain weight.So discovering the crucial genes that control the growth and development of endosperm is the key routine of analyzing the grain's genetical mechanism of growth and formation as well as increasing the yield.A natural mutant found in field breeding was used in this study,which was an insufficient grain-filling performance.The normal and mutation kernels on ear appear at separation ratio of 3:1,controlled by a recessive gene as the classical Mendelian inheritance.By using 609 plants for a segregation population,this gene was mapped on 2.03 bin of chromosome 2 in maize between the SSR primers bnlg1064 and chr2.03-20-1.The molecular markers closely linked to the target genes bnlg1064 and chr2.03-20-1 were used for detecting recombinant plants with 11000 of normal seeds population,which were derived from the self-pollinated normal plants of the segregation population.520 recombinant plants of different genotypes on two markers were selected,and its phenotype was identified in the field.A total of 252 new molecular markers were exploited in the region by means of the B73 genome sequence,and 9 polymorphism markers were detected.Finally,the target gene was mapped between chr2.03-174 and chr2.03-228,with a 950 kb physical distance.Using bioinformatic methods,15 candidate genes have been predicted with GO annotation in this region.