Determining mitochondrial molecular markers suitable for genetic diversity analysis of Cordyceps militaris

Abstract:

Abstract:［Objective］To screen efficient molecular markers suitable for genetic diversity analysis of Cordyceps militaris from mitochondrial DNA.［Methods］We amplified 12 mitochondrial DNA fragments and 3 nuclear DNA fragments from each of 20 C. militaris isolates and analyzed nucleotide variations on these DNA fragments.［Results］We revealed a greatly higher genetic variation in mitochondrial DNA fragments than in nuclear DNA fragments． Specifically，C. militaris isolates exhibited intron presence/absence diversity in some mitochondrial fragments，and more variable sites were found in mitochondrial fragments than in nuclear fragments. The extent of nucleotide variations also varied by mitochondrial fragment，and intronic proteins seemed to be more vulnerable to amino acid changes than exonic proteins. Genetic diversity increased with the number of molecular markers used.［Conclusion］We recommended using (in order) nad3-cox2，cox2-nad5，cox2，cox3，cob，and cox1 for future genetic diversity and population genetic studies of C.militaris.