Identification of a Cytoplasmic Male Sterile Line NEA in Brassica napus L. and Its Genetic Studies

Male sterile NEA plants were identified in progenies of the radiated 92P×Aggregate-silique in Brassica napus L. In 1993. Their progeny plants from test crossing and open pollination were 100％ male sterile. The double-low male sterile lines JL-4 and JL-18 were bred through successive backcrossing of the double -low variety No. 4 and No. 18 in Brassica napus L. To NEA. Restorer lines 6720 and 6722 with significant heterosis in F1 were developed. The results from investigating the restoring-maintaining relationship and inheritance of the restorer gene indicated that JL-4 and JL-18 were different from both PolCMS and Shan 2A type,and their restorer gene was controlled by a pair of dominant genic genes.