The state tree of Tamil Nadu, Borassus flabellifer L. is a nature’s gift to the mankind. It is plant that serves various ecological, medicinal, economical and sociological benefits to the society. It a plant of heaven that could sustain adverse climatic conditions and withstand natural calamities. It is one among the most beneficial species that has economical and medicinal value for each and every part. It found widely in tropical and arid countries ranging from India through South-East Asia to New Guinea. The plant has a very close connection with the rural livelihood and cottage and agro based industries of Indian economy. The utility of the plant could be widely classified into Non-edible, edible and value addition based uses. This paper attempts to give a birds eye view about palmyra’s distribution, nutritional and medicinal properties, different utility forms and the impact on rural livelihood.

In the present study two sesame varieties viz., TMV7 and SVPR1 were treated with varying doses of gamma rays (250, 300, 350, 400 and 450 Gy) and Ethyl Methane Sulphonate (EMS) of different concentrations viz.,0.20, 0.40 and 0.60%. The seed germination percentage was greatly affected by mutagenic treatment of gamma rays and EMS which showed a negative dose dependent relationship in both the varieties. The expected LD50 values were calculated through probit analysis. The LD50 values for TMV7 and SVPR1 were fixed at 416.86 Gy and 389.04 Gy for gamma rays and 0.490 % and 0.349% for EMS. The germination percentage of SVPR1 was greatly reduced (17.80 & 20.55 %) and the lethal dose to kill fifty per cent of mutated population was lower (6.68% & 28.78%) than that of TMV7 in both gamma ray and EMS treatment. EMS treatment exhibited significant reduction in seed germination (62.16 % & 66.67 %) than gamma irradiation (56.76 % & 54.55 %) in TMV7 and SVPR1 respectively. The study concluded that both the mutagens are effective to produce significant variations in sesame which can be further explored for mutation mapping.

The present study envisaged the effects of two mutagens, gamma rays and EMS on the phenotypes of two sesame varieties viz., TMV7 and SVPR1. A known quantity of dry, uniform, and healthy seeds of TMV7 and SVPR 1 were irradiated using Co60 (Cobalt 60) with different doses (250, 300, 350, 400, 450 Gy) of gamma rays. For chemical mutagenesis, different concentrations of EMS @ 0.20%, 0.40% and 0.60% was used and treated for 8 h. The dose-response curve of the probit analysis showed that the optimal lethal dose for SVPR1was lower than TMV7. The expected LD50 values of gamma radiation for TMV 7 and SVPR1 were 403.91Gy and 343.84Gy, respectively. For EMS, the expected LD50 values are 0.525 % and 0.276% for TMV7 and SVPR1 respectively. Germination and pollen fertility declined linearly with an increase in dose or concentration of the mutagens. Three classes of chlorophyll mutants viz., xantha, chlorine, and viridis in M2 generation reveals a dose dependent relationship between mutagens and frequency of chlorophyll mutants. Mutagenic effectiveness was higher at lower doses whereas mutagenic efficiency was observed higher at extremity doses in both the varieties. The overall considerations on M1 generation effects showed that SVPR1was highly sensitive to gamma rays and TMV7 produced more viable mutationsthan SVPR1. The current studies suggest gamma rays as an efficient mutagen to induce essential mutations in TMV7 for the further crop improvement program.