Effect of single and recurrent gamma irradiation on in vitro shoot cultures of banana

Abstract

Multiple shoot cultures of three banana cultivars belonging to AAA and AAB genomic groups (Basari, Chakkarakela and Rasthali) were irradiated with gamma rays. The percentage of individual shoot survival declined with increase in irradiation dose indicating an inverse relationship between the two parameters. Lethal dose of 50% was found to be 30Gy. Lower doses (10, 20Gy) enhanced shoot multiplication ratio, which however decreased with increased dosage. AAB cultivars appeared to be more sensitive as compared to AAA cultivars. The multiple shoots were also subjected to recurrent mutagenesis at an interval of 15 days. The percent (%) survival was found to decrease after each irradiation treatment, whereas multiplication ratio was found to be enhanced after third irradiation in Basrai. Individual shoots derived after different irradiation experiments were rooted and the plantlets were hardened in the green house. Among these, few showed morphological variations such as thick shiny dark green colored leaves, ovate leaves and a dwarf with a rosette of leaves in AAB cultivar, Rasthali. This is the first report on the effect of recurrent gamma irradiation on in vitro shoot cultures of banana. Copyright © by The Haworth Press, Inc. All rights reserved.