MANIPULATION OF LEAF MORPHOLOGY AND TUBER GROWTH PATTERN THROUGH MUTAGENESIS FOR EVOLVING NEW ECONOMIC PLANT TYPE IN DIOSCOREA FLORIBUNDA MART. & GAL.
Tuber pieces of Dioscorea floribunda Mart. & Gal. were treated with 0.05, 0.15 and 0.25 percent Ethyl methane sulphonate (EMS) and 0.02, 0.06 and 0.10 percent N-Methyl-N'-nitro-N-nitrosoguanidin (NG) and irradiated with 2,4,6,8 and 10 KR gamma rays to induce mutation. Sprouting of tubers decreased with increase in the doses of the mutagens and with gamma radiations above 6 KR there was total inhibition of sprouting. A novel complete green leaf mutant as against grey-blotched leaves in normal plant was obtained with 0.05 percent EMS treatment. The positive correlation established between the chlorophyll content and the tuber yield in the species shows that the complete green leaf character can be useful in evolving new economic plant type in the species. Another mutant with higher tuber yield of 88.63 tonnes per ha and diosgenin content of 4.43 percent as against 62.01 tonnes tubers per ha with 3.00 percent diosgenin in normal population was obtained with 0.15 percent EMS treatment. A compact tuber mutant character obtained in 0.15 percent EMS and 0.02, 0.06 and 0.10 percent NG treated populations can be useful for increased production per unit area by increasing the population density.
EMS proved to be a better mutagen compared to NG and gamma radiations for inducing better genotype for increased tuber yield as well as higher diosgenin content in the species.
Sahoo, S., Saxena, H.O. and Dutta, P.K. (1986). MANIPULATION OF LEAF MORPHOLOGY AND TUBER GROWTH PATTERN THROUGH MUTAGENESIS FOR EVOLVING NEW ECONOMIC PLANT TYPE IN DIOSCOREA FLORIBUNDA MART. & GAL.. Acta Hortic. 188, 135-138