Banana somaclonal variation assessed by Amplified Fragment Length Polymorphism profiles at early cycles of in vitro culture

Abstract

Banana micropropagation for obtaining free-virus plants frequently provokes somaclonal variation that could increase useful genetic variability in this asexually propagated crop. Both exploring the cycle of in vitro culture in which somaclonal variation occurs and the amount of generated polymorphism, are necessary. In this work, preliminary results of somaclonal variation during early cycles of banana in vitro culture are reported. Four randomly selected regenerated plants from the fifth cycle and two samples from the mother plant were analyzed. A total of 36 AFLP primer combinations were assayed, and 24 of them produced amplicons varying among 50-500 bp. The mother plant presented a total of 125 different amplicons while the regenerated plants jointly showed 131 different amplicons with a mean of 119.75 ± 3.97 per individual. High level of DNA polymorphism (24.43%) was found among micropropagated plants and, additionally, the occurrence of somaclonal variation at earlier cycles was suggested by multivariate analysis of Principal Coordinates. In this study, somaclonal variation at early cycles of banana micropropagation was validated and the adequacy of AFLP technique to assess it at the molecular level was verified. The phenotypic effects of the detected somaclonal variations remain to be evaluated.