Cloning and use of low copy sequence genomic DNA for RFLP analysis of somaclones in mustard (Brassica juncea(L) Czren and Coss)

Abstract

Brassica juncea(L.) Czern and Coss genomic DNA frogments of 0.5 to 2.5 kb size, obtained by Pst I digestion were cloned into the pUC18 plasmid vector. Screening of the partial library by dat blot hybridization using labelled total genomic DNA as probe revealed that about 45% of the clones carry low copy number DNA sequences. Using some of these clones as probes, DNA polymorphism could be detected among somacloned of B. juncea cv. Vargna.