Effectiveness and efficiency of mutagens and induced variability in clusterbean (Cyamopsis tetragonoloba)

Abstract

An experiment was conducted during 2003–06 to study the variability for adaptability over the locations of clusterbean [Cyamopsis tetragonoloba (L.) Taub.]. Healthy and pure seeds of 2 clusterbean cultivars (‘RGC 936’ and ‘HG 365’) were treated with gamma rays (10, 20, 30 and 40 kR) and ethyl methane sulphonate (0.1, 0.2, 0.3 and 0.4%). A steady reduction in germination and subsequent survival of the treated population, seedling height and pollen fertility were observed with the increasing doses/concentrations of mutagens in both the cultivars regardless of the mutagens used. Both mutagenic effectiveness and efficiency generally decreased with increasing doses/concentrations of mutagens. The efficiency of gamma rays was more in all the 3 parameters of biological damage compared to ethyl methane sulphonate in both the cultivars. The coefficients of variation for all the quantitative characters were of higher magnitude compared to control in both the cultivars. Linear increase in variability in the treated population was recorded with the increasing doses/concentrations of mutagens in both the cultivars.