Genetic Effect Of Amylose Maize In Different Genetype And The Linkage Drag Analysis Of Endosperm Mutation Gene Ae By SSR

This paper studied two backcross generations BC1F1 and BC1F2 of 24 cross from three donor parents of endosperm mutation gene ae and eight maize inbred lines, tested the kilo-grain weight and amylose content of inbred lines themselves and their cross to find inherent genetic regularity. It was analyzed that Linkage drag of different recurrent parent at two flanks in two populations by molecular–assistance selection and that restoring ratio of two populations by the SSR markers which ae even distributed in chromosome 5. The main results were as follows:Amylose content of most cross rose in BC1F2, but kilo-grain weightiness decreased instead. Even if genetic background was not restored to recurrent parent, three genotype donors have strong influence on amylose content and kilo-grain weightiness of backcross generation; Different donor gene ae had variance expression difference in recurrent parent under different genetic background.The result of studying on the recurrent parent of maize heterotic groups showed it had huge variance in amylose content and kilo-grain weightiness in different heterotic groups, it was initial to select recurrent parent which was beneficial to express gene ae. In the front material of backcross, there was no variance cooperation between amylose content and kilo-grain weightiness.Linkage drag at two flanks was controlled in 13.2cM and 17.2cM in CHBC1F2 population by SSR markers, linkage drag at one flank was controlled in 13.9cM in DHBC1F2 population.In CHBC1F2 population, using SSR markers selected from maize chromosome 5 to do background selection on 10 individuals those linkage drag at two flanks had been limited to 13.2cM and 17.2cM,in DHBC1F2 population, using SSR markers selected from maize chromosome 5 to do background selection on 13 individuals which linkage drag at one flank had been limited to 13.9cM.The results showed that genetic background resemblance of individuals in CHBC1F2 population to the recurrent parent's was 57.1%～85.7%, mean 70.8%.The genetic background resemblance of individuals in DHBC1F2 population to the recurrent parent's is 6.3%～87.5%,mean 72.6%.It is possible to identify recombination individual of targeted gene through a map of high density(10cM～20cM per marker).It reduced unnecessary fragment of chromosome and eliminated linkage drag of targeted gene in backcross breeding.It is necessary to establish a huge population and find more closely linked to the targeted gene if the linkage drag was eliminated to even lower...