Effect of EMS on Induction of Mutations in Zamioculcas zamiifolia Engl. for Novel Plant Architecture

Abstract

Zamioculcas zamiifolia Engl. is a vegetatively propagated ornamental foliage plant with limited commercially available variation. This study evaluated ethyl methanesulphonate (EMS) treatments for inducing variability in rhizome-initiated mature leaflets under shade-net conditions at the University of Agricultural Sciences, GKVK, Bengaluru, during 2021–2022. Leaflets were exposed for 2 h to EMS concentrations of 0.06, 0.08, 0.10, 0.12, 0.14, or 0.16%, while untreated leaflets served as the control. Mortality, rhizome and root development, shoot-bud initiation, leaf formation, leaflet traits, plant height, rhizome diameter, chlorophyll content, and visible variants were assessed. The median lethal dose (LD₅₀) was recorded at 0.12% EMS. The untreated control showed the earliest rhizome formation (16.50 days after rhizome initiation [DAI]), root initiation (4.80 DAI), and shoot-bud initiation (62.50 DAI). It also produced the highest number of roots (4.90) and the greatest rhizome diameter (1.62 cm) at 120 DAI. Shoot-bud initiation was delayed as EMS concentration increased, reaching 149.50 DAI at 0.16% EMS. Two shoot buds were observed under the 0.10% treatment. Cotyledonary-like leaves, new leaves, and measurable leaflet and plant-height traits occurred only in the control. No visible variation in leaflet colour, variegation, or shape was recorded during the observation period. The findings indicate that the tested EMS concentrations suppressed growth and delayed development, while 0.12% represented the LD₅₀ under the experimental conditions.