Isozyme analysis based genetic fidelity assessment of micropropagated banana plants

Abstract

Isozyme studies of micropropagated and mother plants of banana cvs. Matti, Ney Poovan, Kechulepa, Dwarf Cavendish, Malbhog, Champa, B.B. Battisa and FHIA-1 were done to test their genetic fidelity. The banding patterns as revealed by electrophoretic variations were evaluated with respect to isozymes of acid phosphatase, catalase, esterase and peroxidase as markers. The genetic fidelity of micropropagated plants and the relationship of the different cultivars were determined by dendrogram using numerical taxonomy and multivariate analysis system(NTSYS). A clustered dendrogram was prepared by unweighted pair group method using averages (UPGAMA) method. At 87% similarity, the micropropagated and mother plants were clustered in four groups reflecting their genomic constitution. Cvs. Matti (AA) and Dwarf Cavendish (AAA) with similar ‘A’ genome were categorized in Cluster I. Cluster II comprised of cvs. Ney Poovan (AB), B.B. Battisa (ABB) and FHIA-1(AAAB) with genomic constitution of both ‘A’ and ‘B’ type. Cvs. Champa (AAB) and Malbhog (AAB) with similar genome were grouped inCluster III. Cluster IV contained the cv. Kechulepa (BB) having only ‘B’ genome. However, there was no somaclonal variation among the micropropagated plants and they showed 100% genetic similarity. Thus, the isozyme studies could be a reliable marker for testing the genetic fidelity of micropropagated plants and for evaluating the diversity among the banana germplasm.