The results of drug sensitivity showed that amphotericin (AMB) and nystatin (NYS) were the most sensitive and flucytosine (5- Fc ) was the most resistant (54.2%).

The discovery of a previously unknown nucleotide, called hydroxymethylcytosine, inside animal cells suggests a new mechanism for regulating gene expression.

The methyl groups are attached only to specific cytosine bases - one of the four building blocks of DNA.

It or its corresponding nucleoside or nucleotide may be prepared from DNA by selective techniques of hydrolysis.

This paper is the first time to analyse cytosine methylation in navel oranges using MSAP, indicating MSAP technique is efficient for detection of cytosine methylation in navel orange genomes.