INTROGRESSION OF A GENE RESTORING FERTILITY TO CMS (TRACHYSTOMA) BRASSICA-JUNCEA AND THE GENETICS OF RESTORATION

A dominant gene restoring fertility to a cytoplasmic male sterile (CMS ) line of Brassica juncea was derived from the somatic hybrid Trachyst oma ballii + B. juncea. Its introgression resulted from forced pairing between chromosomes of the cultivar 'Pusa Bold' and chromosomes of th e fusion hybrid. Segregation ratios of this fertility restorer gene fo llowed a monogenic pattern. The introgression of the fertility restore r gene did not cause any abnormalities, such as reduced fertility; pol len and seed fertilities of the restored plants were over 90%. Restore d fertile and CMS plants exhibited similar Southern hybridization patt erns when probed with the mitochondrial probe atp6.