Genetic Analysis And Gene Mapping Of Maize Small Kernel Mutant Sk-like1

Maize(Zea mays)is one of the major food crops with an important position in the world’s agricultural production,and the kernel is the vector of maize yield.So study on genes controlling development of maize kernel has vital scientific significance to understand the functions and regulatory mechanisms to increase maize grain yield.Our research makes a study of a maize kernel mutant,named sk-like1,which was generated by outcrossing the Mu active lines as male to plants of maize hybrid line zhengdan 958.By multi-self-pollination,the mutant sk-like1 is inherited stably,and genetic tests showed that it is controlled by a recessive single gene.We measured the length,width,thickness and hundred-kernel weight,and the results showed only the last index had significant difference between the mutant and the wild type tested by a stastistical method of two-tailed t-test: its hundred-kernel weight is 9.23 gram,just 47% weight of the wild type,s.We also observed just 10% maize seedlings could survived,and few of them was able to grow up.It might be related with the severity degree of gene mutation.By using BSR-seq technique,the sk-like1 gene is located in 165~169Mb on chromosome 8 in Zea mays.Based on the former information and the method of map-based cloning,the gene is gradually narrowed in a 380 kb location by using the expanded genetic mapping group.Then we can seek SSR,In Dels or SNP tags to make a much smaller range.On the other hand,there are 15 gene-encoding proteins in the 380 kb range according to the maize genome sequence,then we would look for whether have genetic differences between the mutant and the wild type,and combine with the result of further fine mapping,finally we could seek out the sk-like1 candidate gene.