Phenotypic characterization and genetic variability, genetic diversity of elite mutants of Jasminum auriculatum Vahl and induction of homeotic mutants

Abstract

Jasmine is commonly propagated vegetatively, representing a poor genetic diversity base for effective selection to make further improvements in yield and quality. Hence, research conducted at TNAU during 2021-2023 aimed to induce genetic variation in J. auriculatum through the application of physical (gamma rays) and chemical (Ethyl Methane Sulphonate; EMS) mutagens. The M1V3 generation putative mutants of J. auriculatum cv. CO.1 was evaluated under field condition. It was observed that mutants derived from treatments 10 Gy gamma irradiation and 35 mM EMS exhibited maximum vegetative growth parameters, including plant height, stem girth, internodal length, number of leaves, leaf width and leaf thickness and flower quality parameters viz., flower bud length and corolla tube length. These values were surpassed those of parent CO.1. The phenotypic coefficient of variation (PCV) was prominent than genotypic coefficient of variation (GCV) for all the traits studied, indicating the appreciable influence is not only by the genetic factor but highly influenced by the environment. The higher magnitude of broad sense heritability coupled with high genetic advance as % of mean was observed for corolla tube length at 15 Gy, 35 mM and 40 mM, bud girth at 10 Gy and 35 mM, flower diameter at 35 mM. Homeotic mutants were identified and isolated from the mutated population. This study further explored the reliability of the observed traits for making simple selection for efficient improvement of jasmine.