Abstract
Using restriction endonuclease analysis, chloroplast DNA (ctDNA) of normal or male sterile cytoplasms in Brassica napus were compared. There were some differences in restriction patterns of ctDNA from two types of cytoplasms digested with several restriction endonucleases. Based on the fragment pattern of Eco RI digested ctDNA, there were two types of ctDNAs in B, napus and one type of ctDNA was coincident with male sterile cytoplasm, whereas another type of ctDNA was observed only in the normal cytoplasm.
