Mutagenic effect of ethyl-methyl sulphonate on in vitro nodal segments of acid lime cv. PKM-1

Abstract

Induced mutagenesis is an essential plant breeding tool which involves the generation of allelic variants of genes that modulate the expression of traits. To minimize the population loss due to excess dose rate of mutagens, it is necessary to optimize the dosage (LD50). In a mutation breeding experiment, LD50 gives an indication of the response of different types of explants of a species to mutagen, so that the right dose(s) for the main field experiment can be fixed to obtain beneficial mutants. In the present investigation, axenic nodal segments of acid lime cv. PKM-1 were subjected to different dosages of chemical mutagen (Ethyl methylsulphonate) ranging from 10 to 45 mM to find their effect on different growth related traits. The results revealed a gradual and significant reduction in survival of nodal segments, with increase in dose of the mutagens. Probit curve analysis was carried out based on the survival of nodal segments and the LD50 was fixed as 25 mM for chemical mutagenesis. Based on the LD50 the population was maintained for further study.