genetic enhancement of gloriosa superba l for high yield and colchicine content through mutagenesis

Abstract

Induced mutagenesis with Ethyl Methane Sulphonate (EMS), and gamma rays, newlinetreatment were attempted in Gloriosa superba at Department of Genetics and Plant newlineBreeding, Faculty of Agriculture, Annamalai University. The sensitivity and survival newlinestudies concluded that the LD50 value of EMS and gamma rays were 1.5% and 3.0 Kr newlinerespectively. A trend of reduced plant growth with increased doses of mutagens was newlineobserved. The tubers were subjected to four concentrations of Ethyl Metane Sulfonate newlineviz., 1.0, 1.5, 2.0 and 2.5% and gamma irradiation at four levels viz., 2.5, 3.0, 3.5 and 4.0 newlineKr for the experimental study. In VM1 generation a marginal reduction in plant height newlineand days to 50 per cent flowering was observed in all the treatments of Dharapuram, newlineNellore and Vedaranyam ecotypes. The maximum increase for plant height and days newlineto 50 per cent flowering was noticed at 1.0% EMS in Chittor and Mulanur ecotypes newlinerespectively. The maximum number of pods per plant was observed in Mulanur newlineecotype at 1.0% EMS followed by Chittor and Arupukottai ecotypes. An increase in newlinenumber of seeds per pod was observed at 1.0% EMS in Mulanur followed by Chittor newlineecotypes. Fresh and dry seed yields were high in three mutant ecotypes viz., Chittor, Mulanur and Arupukottai that was treated with 1.0% EMS. The maximum tuber newlinelength and tuber weight was registered at 1.0% EMS in Mulanur ecotype. The newlinecolchicine content of seeds was found to be high at 1.0% EMS in Arupukottai newlineecotype. Based on the mean performance of VM1 generation three ecotypes viz., newlineArupukottai, Chittor and Mulanur were selected and forwarded to VM2 generation. newlineThe average plant height in VM2 generation was reduced when compared newlineto VM1 generation. A slight delay in flowering was observed in all the treatment in newlineMulanur ecotype than the control. An increase in number of pods per plant was newlinenoticed in chemical treatments in two ecotypes viz., Arupukottai and Chittor. The newlinenumber of seeds per pod was high in chemical treatments for all the ecotypes than the newlinecontrol.