Molecular differentiation of Chenopodium album complex and some related species using ISSR profiles and ITS sequences.
ABSTRACT The present study was undertaken to understand the genetic differentiation and relationships in various components of C. album complex, C. giganteum and some related species using inter simple sequence repeats (ISSR) profiles and internal transcribed spacer (ITS) sequences. The relationships based on UPGMA dendrograms have shown the heterogenous nature of C. album complex. The 2x taxa while showing close relation among themselves are sharply segregated from 4x and 6x taxa belonging to C. album and C. giganteum. Among the three cytotypes from North Indian plains the 4x shows greater similarity to 6x than to 2x which is corroborated by the karyotypic studies. Furthermore, the 6x C. album and C. giganteum accessions of American and European origin are clearly segregated from those of Indian origin which may show their separate origin. Other related species show relationships according to their taxonomic position. The present study based on ISSR profiles and ITS sequences has therefore been very useful in explaining the relationships between various components of C. album complex and related species. However, more work needs to be done using different CpDNA loci to define correct species boundary of the taxa under C. album complex from Himalayas and North Indian Plains.