Effect of physical and chemical mutagens on floral characters of Jasminum sambac cv. Gundumalli and isolation of important mutants

Investigation was carried out during 2008–09 to study the effect of physical and chemical mutagens on floral characters of J. sambac cv. Gundumalli and isolation of important mutants. The semi hard wood cuttings of gundumalli were treated with mutagens viz. gamma rays alone and in combination with ethyl methyl sulphonate (EMS) at different doses including control (untreated). In general, the treated population had manifested reduced expression than the control (untreated population) in most of the floral characters. Higher the dose of mutagens, there was reduction in the expressivity of the traits. The mean stalk length decreased with the increase in the irradiated population and it was minimum with 2.5kR+30mM EMS (0.89±0.021 cm). The mutagenic treatment 2.0 kR followed by 1.5 kR + 30 mM EMS manifested higher variability in terms of PCV and GCV recording the maximum flower range of (3–35) and (5–27). The floral characters like bud length and flower weight decreased with increase in the doses while the flower width did not follow a definite trend. Induced mutations produced higher amount of phenotypic and genotypic co-efficient of variation for number of flowers, flower weight indicating the scope for improvement of gundumalli for yield and novelty by selection.